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1

Using Mesoscale Weather Model Output as Boundary Conditions for Atmospheric Large-Eddy Simulations and Wind-Plant Aerodynamic Simulations (Presentation)  

SciTech Connect (OSTI)

Wind plant aerodynamics are directly affected by the microscale weather, which is directly influenced by the mesoscale weather. Microscale weather refers to processes that occur within the atmospheric boundary layer with the largest scales being a few hundred meters to a few kilometers depending on the atmospheric stability of the boundary layer. Mesoscale weather refers to large weather patterns, such as weather fronts, with the largest scales being hundreds of kilometers wide. Sometimes microscale simulations that capture mesoscale-driven variations (changes in wind speed and direction over time or across the spatial extent of a wind plant) are important in wind plant analysis. In this paper, we present our preliminary work in coupling a mesoscale weather model with a microscale atmospheric large-eddy simulation model. The coupling is one-way beginning with the weather model and ending with a computational fluid dynamics solver using the weather model in coarse large-eddy simulation mode as an intermediary. We simulate one hour of daytime moderately convective microscale development driven by the mesoscale data, which are applied as initial and boundary conditions to the microscale domain, at a site in Iowa. We analyze the time and distance necessary for the smallest resolvable microscales to develop.

Churchfield, M. J.; Michalakes, J.; Vanderwende, B.; Lee, S.; Sprague, M. A.; Lundquist, J. K.; Moriarty, P. J.

2013-10-01T23:59:59.000Z

2

Mesoscale Modeling Spring Semester 2014  

E-Print Network [OSTI]

is to present the development of the basic equations used in mesoscale models, as well as the various methods Integrity: All students are subject to the policies regarding academic integrity found in Section 1://www.conflictresolution.colostate.edu/conduct-code). Other information on academic integrity can be found on the Learning@CSU website (http://learning.colostate.edu/integrity

3

Mesoscale Atmospheric Dispersion, 2001, Ed. Z. Boybeyi, WIT Publications, Southampton, UK, Advances in Air Pollution, Vol 9, p. 424.  

E-Print Network [OSTI]

surface­atmosphere exchanges in mesoscale air pollution systems Devdutta S. Niyogi & Sethu Raman NorthMesoscale Atmospheric Dispersion, 2001, Ed. Z. Boybeyi, WIT Publications, Southampton, UK, Advances in Air Pollution, Vol 9, p. 424. Chapter 9 Numerical modeling of gas deposition and bi- directional

Raman, Sethu

4

Rotational and divergent kinetic energy in the mesoscale model ALADIN  

E-Print Network [OSTI]

energy, divergent energy, ALADIN, limited-area modelling 1. Introduction Horizontal divergenceRotational and divergent kinetic energy in the mesoscale model ALADIN By V. BLAZ ICA1 *, N. Z AGAR1 received 7 June 2012; in final form 7 March 2013) ABSTRACT Kinetic energy spectra from the mesoscale

Zagar, Nedjeljka

5

Coupling a Mesoscale Numerical Weather Prediction Model with Large-Eddy Simulation for Realistic Wind Plant Aerodynamics Simulations (Poster)  

SciTech Connect (OSTI)

Wind plant aerodynamics are influenced by a combination of microscale and mesoscale phenomena. Incorporating mesoscale atmospheric forcing (e.g., diurnal cycles and frontal passages) into wind plant simulations can lead to a more accurate representation of microscale flows, aerodynamics, and wind turbine/plant performance. Our goal is to couple a numerical weather prediction model that can represent mesoscale flow [specifically the Weather Research and Forecasting model] with a microscale LES model (OpenFOAM) that can predict microscale turbulence and wake losses.

Draxl, C.; Churchfield, M.; Mirocha, J.; Lee, S.; Lundquist, J.; Michalakes, J.; Moriarty, P.; Purkayastha, A.; Sprague, M.; Vanderwende, B.

2014-06-01T23:59:59.000Z

6

ADVANCES IN ATMOSPHERIC SCIENCES, VOL. 27, NO. 2, 2010, 243252 Mesoscale Barotropic Instability of Vortex Rossby  

E-Print Network [OSTI]

ADVANCES IN ATMOSPHERIC SCIENCES, VOL. 27, NO. 2, 2010, 243­252 Mesoscale Barotropic Instability of Vortex Rossby Waves in Tropical Cyclones ZHONG Wei1 ( Í), LU Han-Cheng1 (ö ), and Da-Lin ZHANG2 1 Institute of Meteorology, PLA University of Science and Technology, Nanjing 211101 2 Department

Zhang, Da-Lin

7

Soil moisture in complex terrain: quantifying effects on atmospheric boundary layer flow and providing improved surface boundary conditions for mesoscale models  

E-Print Network [OSTI]

compressible numerical weather prediction model incompressible numerical weather prediction model withcompressible numerical weather prediction model in

Daniels, Megan Hanako

2010-01-01T23:59:59.000Z

8

Wind resource assessment with a mesoscale non-hydrostatic model  

E-Print Network [OSTI]

Wind resource assessment with a mesoscale non- hydrostatic model Vincent Guénard, Center for Energy is developed for assessing the wind resource and its uncertainty. The work focuses on an existing wind farm mast measurements. The wind speed and turbulence fields are discussed. It is shown that the k

Boyer, Edmond

9

MESOSCALE MODELLING OF WIND ENERGY OVER NON-HOMOGENEOUS TERRAIN  

E-Print Network [OSTI]

MESOSCALE MODELLING OF WIND ENERGY OVER NON-HOMOGENEOUS TERRAIN (ReviewArticle) Y. MAHRER.1. OBSERVATIONALAPPROACHES Evaluations of wind energy based on wind observations (usually surface winds) at well, the resolution of the wind energy pattern throughout an extended area by this methodology requires a large number

Pielke, Roger A.

10

WIND ATLAS FOR EGYPT: MEASUREMENTS, MICRO-AND MESOSCALE MODELLING  

E-Print Network [OSTI]

sets for evaluating the potential wind power output from large electricity-producing wind turbine and accurate wind atlas data sets for evaluating the potential wind power output from large electricityWIND ATLAS FOR EGYPT: MEASUREMENTS, MICRO- AND MESOSCALE MODELLING Niels G. Mortensen1 , Jens

11

Mesoscale Modeling of LX-17 Under Isentropic Compression  

SciTech Connect (OSTI)

Mesoscale simulations of LX-17 incorporating different equilibrium mixture models were used to investigate the unreacted equation-of-state (UEOS) of TATB. Candidate TATB UEOS were calculated using the equilibrium mixture models and benchmarked with mesoscale simulations of isentropic compression experiments (ICE). X-ray computed tomography (XRCT) data provided the basis for initializing the simulations with realistic microstructural details. Three equilibrium mixture models were used in this study. The single constituent with conservation equations (SCCE) model was based on a mass-fraction weighted specific volume and the conservation of mass, momentum, and energy. The single constituent equation-of-state (SCEOS) model was based on a mass-fraction weighted specific volume and the equation-of-state of the constituents. The kinetic energy averaging (KEA) model was based on a mass-fraction weighted particle velocity mixture rule and the conservation equations. The SCEOS model yielded the stiffest TATB EOS (0.121{micro} + 0.4958{micro}{sup 2} + 2.0473{micro}{sup 3}) and, when incorporated in mesoscale simulations of the ICE, demonstrated the best agreement with VISAR velocity data for both specimen thicknesses. The SCCE model yielded a relatively more compliant EOS (0.1999{micro}-0.6967{micro}{sup 2} + 4.9546{micro}{sup 3}) and the KEA model yielded the most compliant EOS (0.1999{micro}-0.6967{micro}{sup 2}+4.9546{micro}{sup 3}) of all the equilibrium mixture models. Mesoscale simulations with the lower density TATB adiabatic EOS data demonstrated the least agreement with VISAR velocity data.

Springer, H K; Willey, T M; Friedman, G; Fried, L E; Vandersall, K S; Baer, M R

2010-03-06T23:59:59.000Z

12

Processing of cloud condensation nuclei by collision-coalescence in a mesoscale model  

E-Print Network [OSTI]

The Naval Research Laboratory's Coupled Ocean-Atmosphere Mesoscale Prediction System (COAMPS) is employed to explore the relative importance of source, sink, and transport processes in producing an accurate forecast of the ...

Mechem, David B.; Robinson, Paul C.; Kogan, Yefim L.

2006-09-26T23:59:59.000Z

13

MESOSCALE AVERAGING OF NUCLEATION AND GROWTH MODELS  

E-Print Network [OSTI]

(cf. e.g. [49]), semiconductor crystal growth (cf. [37]), biomineralization (cf. e.g. [48]), DNA (cf. e.g. [2, 4, 10, 26, 28, 32]). The aim of this paper is to bridge between these two type of models

Burger, Martin

14

Atmosphere Model  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)ProductssondeadjustsondeadjustAbout theOFFICEAmesApplication2ArgonneAssemblyDemandPlasma4 Medicare5Dust

15

Meso-Scale Model for Simulations of Concrete Subjected to Cryogenic Temperatures  

E-Print Network [OSTI]

software ABAQUS. In this model, concrete is considered as a 3- phase composite material in a meso-scale structure: mortar matrix, aggregate, and interfacial transmission zone (ITZ). The Concrete Damage Plasticity model in ABAQUS is used to represent...

Masad, Noor Ahmad

2013-07-17T23:59:59.000Z

16

STATISTICAL MECHANICS MODELING OF MESOSCALE DEFORMATION IN METALS  

SciTech Connect (OSTI)

The research under this project focused on a theoretical and computational modeling of dislocation dynamics of mesoscale deformation of metal single crystals. Specifically, the work aimed to implement a continuum statistical theory of dislocations to understand strain hardening and cell structure formation under monotonic loading. These aspects of crystal deformation are manifestations of the evolution of the underlying dislocation system under mechanical loading. The project had three research tasks: 1) Investigating the statistical characteristics of dislocation systems in deformed crystals. 2) Formulating kinetic equations of dislocations and coupling these kinetics equations and crystal mechanics. 3) Computational solution of coupled crystal mechanics and dislocation kinetics. Comparison of dislocation dynamics predictions with experimental results in the area of statistical properties of dislocations and their field was also a part of the proposed effort. In the first research task, the dislocation dynamics simulation method was used to investigate the spatial, orientation, velocity, and temporal statistics of dynamical dislocation systems, and on the use of the results from this investigation to complete the kinetic description of dislocations. The second task focused on completing the formulation of a kinetic theory of dislocations that respects the discrete nature of crystallographic slip and the physics of dislocation motion and dislocation interaction in the crystal. Part of this effort also targeted the theoretical basis for establishing the connection between discrete and continuum representation of dislocations and the analysis of discrete dislocation simulation results within the continuum framework. This part of the research enables the enrichment of the kinetic description with information representing the discrete dislocation systems behavior. The third task focused on the development of physics-inspired numerical methods of solution of the coupled dislocation kinetics and crystal mechanics framework. To a large extent, this task has also been successfully started. We have developed a custom finite-element approach with mesh points being a subset of the underlying crystal structure. When used to predict the evolution of the dislocation system, the planar motion of dislocations is naturally captured for all slip systems, thus minimizing numerical errors and providing simple ways to investigate cross slip and dislocation reactions. Preliminary results in this direction show that we are closer than ever in building a predictive framework for dislocation dynamics and mesoscale plasticity based on the first principles of dislocation dynamics. The rest of the report gives and overview of the research performed under this project and highlights the key results and open questions left for future investigations.

Anter El-Azab

2013-04-08T23:59:59.000Z

17

Mesoscale Modeling During Mixed-Phase Arctic Cloud Experiment  

SciTech Connect (OSTI)

Mixed-phase arctic stratus clouds are the predominant cloud type in the Arctic (Curry et al. 2000) and through various feedback mechanisms exert a strong influence on the Arctic climate. Perhaps one of the most intriguing of their features is that they tend to have liquid tops that precipitate ice. Despite the fact that this situation is colloidally unstable, these cloud systems are quite long lived - from a few days to over a couple of weeks. It has been hypothesized that mixed-phase clouds are maintained through a balance between liquid water condensation resulting from the cloud-top radiative cooling and ice removal by precipitation (Pinto 1998; Harrington et al. 1999). In their modeling study Harrington et al. (1999) found that the maintenance of this balance depends strongly on the ambient concentration of ice forming nucleus (IFN). In a follow-up study, Jiang et al. (2002), using only 30% of IFN concentration predicted by Meyers et al. (1992) IFN parameterization were able to obtain results similar to the observations reported by Pinto (1998). The IFN concentration measurements collected during the Mixed-Phase Arctic Cloud Experiment (M-PACE), conducted in October 2004 over the North Slope of Alaska and the Beaufort Sea (Verlinde et al. 2005), also showed much lower values then those predicted (Prenne, pers. comm.) by currently accepted ice nucleation parameterizations (e.g. Meyers et al. 1992). The goal of this study is to use the extensive IFN data taken during M-PACE to examine what effects low IFN concentrations have on mesoscale cloud structure and coastal dynamics.

Avramov, A.; Harringston, J.Y.; Verlinde, J.

2005-03-18T23:59:59.000Z

18

Meso-scale eects of tropical deforestation in Amazonia: preparatory LBA modelling studies  

E-Print Network [OSTI]

Meso-scale eects of tropical deforestation in Amazonia: preparatory LBA modelling studies A. J forest is good, above deforested areas (pasture) poor. The models' underestimate of the temperature Modelling studies with general circulation models have shown that large-scale deforestation of the Amazon

Paris-Sud XI, Université de

19

Development and Evaluation of a Coupled Photosynthesis-Based Gas Exchange Evapotranspiration Model (GEM) for Mesoscale Weather Forecasting Applications  

E-Print Network [OSTI]

Development and Evaluation of a Coupled Photosynthesis-Based Gas Exchange Evapotranspiration Model (GEM) for Mesoscale Weather Forecasting Applications DEV NIYOGI Department of Agronomy, and Department form 13 May 2008) ABSTRACT Current land surface schemes used for mesoscale weather forecast models use

Niyogi, Dev

20

Spatial-temporal mesoscale modelling of rainfall intensity using gage and radar data  

E-Print Network [OSTI]

Spatial-temporal mesoscale modelling of rainfall intensity using gage and radar data Montserrat fields. Doppler radar data offer better spatial and temporal coverage, but Doppler radar measures values. We use spatial logistic regression to model the probability of rain for both sources of data

Reich, Brian J.

Note: This page contains sample records for the topic "atmospheric mesoscale model" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Atmospheric Dispersion at Spatial Resolutions Below Mesoscale for university of Tennessee SimCenter at Chattanooga: Final Report  

SciTech Connect (OSTI)

In Year 1 of this project, items 1.1 and 1.2 were addressed, as well as item 2.2. The baseline parallel computational simulation tool has been refined significantly over the timeline of this project for the purpose of atmospheric dispersion and transport problems; some of these refinements are documented in Chapter 3. The addition of a concentration transport capability (item 1.2) was completed, along with validation and usage in a highly complex urban environment. Multigrid capability (item 2.2) was a primary focus of Year 1 as well, regardless of the fact that it was scheduled for Year 2. It was determined by the authors that due to the very large nature of the meshes required for atmospheric simulations at mesoscale, multigrid was a key enabling technology for the rest of the project to be successful. Therefore, it was addressed early according to the schedule laid out in the original proposal. The technology behind the multigrid capability is discussed in detail in Chapter 5. Also in Year 1, the issue of ground topography specification is addressed. For simulations of pollutant transport in a given region, a key prerequisite is the specification of the detailed ground topography. The local topography must be placed into a form suitable for generating an unstructured grid both on the topography itself and the atmospheric volume above it; this effort is documented in Chapter 6. In Year 2 of this project, items 1.3 and 2.1 were addressed. Weather data in the form of wind speeds, relative humidity, and baseline pollution levels may be input into the code in order to improve the real-world fidelity of the solutions. Of course, the computational atmospheric boundary layer (ABL) boundary condition developed in Year 1 may still be used when necessary. Cloud cover may be simulated via the levels of actinic flux allowed in photochemical reactions in the atmospheric chemistry model. The primary focus of Year 2 was the formulation of a multispecies capability with included chemical reactions (item 2.1). This proved to be a very arduous task, taking the vast majority of the time and personnel allocation for Year Two. The addition of this capability and related verification is documented in Chapter 7. A discussion of available tropospheric chemistry models is located in Chapter 8; and, a technology demonstrator for the full multispecies capability is detailed in Chapter 9. Item 2.3 has been partially addressed, in that the computation of sensitivity derivatives have been incorporated in the Tenasi code [7]. However, it has not been utilized in this project in order to compute probability distribution functions for pollutant deposition. In order to completely address the integration of weather and sensor data into the code (item 1.3) and integrate with existing sensor networks (item 3.1), a customizable interface was established. Weather data is most commonly available via a real database, and as such, support for accessing these databases is present in the solver source code. For integration functionality, a method of dynamic code customization was developed in Year 3, which is documented in Chapter 11.

Dr. David Whitfield; Dr. Daniel Hyams

2009-09-14T23:59:59.000Z

22

Mesoscale modelling for an offshore wind farm Jake Badger*, Rebecca Barthelmie, Sten Frandsen, Merete Bruun Christiansen  

E-Print Network [OSTI]

Mesoscale modelling for an offshore wind farm Jake Badger*, Rebecca Barthelmie, Sten Frandsen for an offshore wind farm in a coastal location. Spatial gradients and vertical profiles between 25 m and 70 m offshore wind farms tend to be placed within the coastal zone, the region within around 50km from

23

Coupling the High Complexity Land Surface Model ACASA to the Mesoscale Model WRF  

E-Print Network [OSTI]

In this study, the Weather Research and Forecasting Model (WRF) is coupled with the Advanced Canopy-Atmosphere-Soil Algorithm (ACASA), a high complexity land surface model. Although WRF is a state-of-the-art regional ...

Xu, L.

24

Tests of an Ensemble Kalman Filter for Mesoscale and Regional-Scale Data Assimilation. Part II: Imperfect Model Experiments  

E-Print Network [OSTI]

degraded). As in Part I, where the perfect model assumption was utilized, most analysis error reduction of significant model errors due to physical parameterizations by assimilating synthetic sounding and surfaceTests of an Ensemble Kalman Filter for Mesoscale and Regional-Scale Data Assimilation. Part II

Meng, Zhiyong

25

Cloud shading retrieval and assimilation in a satellite-model coupled mesoscale analysis system  

SciTech Connect (OSTI)

A retrieval-assimilation method has been developed as a quantitative means to exploit the information in satellite imagery regarding shading of the ground by clouds, as applied to mesoscale weather analysis. Cloud radiative parameters are retrieved from satellite visible image data and used, along with parameters computed by a numerical model, to control the model's computation of downward radiative fluxes at the ground. These fluxes influence the analysis of ground surface temperatures under clouds. The method is part of a satellite-model coupled four-dimensional analysis system that merges information from visible image data in cloudy areas with infrared sounder data in clear areas, where retrievals of surface temperatures and water vapor concentrations are assimilated. The substantial impact of shading on boundary-layer development and mesoscale circulations was demonstrated in simulations, and the value of assimilating shading retrievals was demonstrated with a case study and with a simulated analysis that included the effects of several potential sources of error. The case study was performed in the northwestern Texas area, where convective cloud development was influenced by the shading effects of a persistent region of stratiform cloud cover. Analyses that included shading retrieval assimilation had consistently smaller shelter-height temperature errors than analyses without shading retrievals. When clear-area surface temperature retrievals from sounder data were analyzed along with cloudy-area shading retrievals, the contrast in heating between the shaded and clear parts of the domain led to large variations in analyzed boundary-layer depths and had a modest impact on analyzed wind flow. The analyzed locations of upward vertical motion corresponded roughly to areas of convective cloud development observed in satellite imagery. 29 refs., 17 figs., 2 tabs.

Lipton, A.E. (Phillips Lab., Hanscom AFB, MA (United States))

1993-11-01T23:59:59.000Z

26

Development of advanced cloud parameterizations to examine air quality, cloud properties, and cloud-radiation feedback in mesoscale models  

SciTech Connect (OSTI)

The distribution of atmospheric pollutants is governed by dynamic processes that create the general conditions for transport and mixing, by microphysical processes that control the evolution of aerosol and cloud particles, and by chemical processes that transform chemical species and form aerosols. Pollutants emitted into the air can undergo homogeneous gas reactions to create a suitable environment for the production by heterogeneous nucleation of embryos composed of a few molecules. The physicochemical properties of preexisting aerosols interact with newly produced embryos to evolve by heteromolecular diffusion and coagulation. Hygroscopic particles wig serve as effective cloud condensation nuclei (CCN), while hydrophobic particles will serve as effective ice-forming nuclei. Clouds form initially by condensation of water vapor on CCN and evolve in a vapor-liquid-solid system by deposition, sublimation, freezing, melting, coagulation, and breakup. Gases and aerosols that enter the clouds undergo aqueous chemical processes and may acidity hydrometer particles. Calculations for solar and longwave radiation fluxes depend on how the respective spectra are modified by absorbers such as H{sub 2}O, CO{sub 2}, O{sub 3}, CH{sub 4}, N{sub 2}O, chlorofruorocarbons, and aerosols. However, the flux calculations are more complicated for cloudy skies, because the cloud optical properties are not well defined. In this paper, key processes such as tropospheric chemistry, cloud microphysics parameterizations, and radiation schemes are reviewed in terms of physicochemical processes occurring, and recommendations are made for the development of advanced modules applicable to mesoscale models.

Lee, In Young

1993-09-01T23:59:59.000Z

27

The reduction of plankton biomass induced by mesoscale stirring: a modeling study in the Benguela upwelling  

E-Print Network [OSTI]

Recent studies, both based on remote sensed data and coupled models, showed a reduction of biological productivity due to vigorous horizontal stirring in upwelling areas. In order to better understand this phenomenon, we consider a system of oceanic flow from the Benguela area coupled with a simple biogeochemical model of Nutrient-Phyto-Zooplankton (NPZ) type. For the flow three different surface velocity fields are considered: one derived from satellite altimetry data, and the other two from a regional numerical model at two different spatial resolutions. We compute horizontal particle dispersion in terms of Lyapunov Exponents, and analyzed their correlations with phytoplankton concentrations. Our modelling approach confirms that in the south Benguela there is a reduction of biological activity when stirring is increased. Two-dimensional offshore advection and latitudinal difference in Primary Production, also mediated by the flow, seem to be the dominant processes involved. We estimate that mesoscale processes are responsible for 30 to 50% of the offshore fluxes of biological tracers. In the northern area, other factors not taken into account in our simulation are influencing the ecosystem. We suggest explanations for these results in the context of studies performed in other eastern boundary upwelling areas.

Ismael Hernndez-Carrasco; Vincent Rossi; Emilio Hernndez-Garca; Veronique Garon; Cristbal Lpez

2013-11-05T23:59:59.000Z

28

Meso-Scale Modeling of Spall in a Heterogeneous Two-Phase Material  

SciTech Connect (OSTI)

The influence of the heterogeneous second-phase particle structure and applied loading conditions on the ductile spall response of a model two-phase material was investigated. Quantitative metallography, three-dimensional (3D) meso-scale simulations (MSS), and small-scale spall experiments provided the foundation for this study. Nodular ductile iron (NDI) was selected as the model two-phase material for this study because it contains a large and readily identifiable second- phase particle population. Second-phase particles serve as the primary void nucleation sites in NDI and are, therefore, central to its ductile spall response. A mathematical model was developed for the NDI second-phase volume fraction that accounted for the non-uniform particle size and spacing distributions within the framework of a length-scale dependent Gaussian probability distribution function (PDF). This model was based on novel multiscale sampling measurements. A methodology was also developed for the computer generation of representative particle structures based on their mathematical description, enabling 3D MSS. MSS were used to investigate the effects of second-phase particle volume fraction and particle size, loading conditions, and physical domain size of simulation on the ductile spall response of a model two-phase material. MSS results reinforce existing model predictions, where the spall strength metric (SSM) logarithmically decreases with increasing particle volume fraction. While SSM predictions are nearly independent of applied load conditions at lower loading rates, which is consistent with previous studies, loading dependencies are observed at higher loading rates. There is also a logarithmic decrease in SSM for increasing (initial) void size, as well. A model was developed to account for the effects of loading rate, particle size, matrix sound-speed, and, in the NDI-specific case, the probabilistic particle volume fraction model. Small-scale spall experiments were designed and executed for the purpose of validating closely-coupled 3D MSS. While the spall strength is nearly independent of specimen thickness, the fragment morphology varies widely. Detailed MSS demonstrate that the interactions between the tensile release waves are altered by specimen thickness and that these interactions are primarily responsible for fragment formation. MSS also provided insights on the regional amplification of damage, which enables the development of predictive void evolution models.

Springer, H K

2008-06-26T23:59:59.000Z

29

Modeling of mesoscale coupled oceanatmosphere interaction and its feedback to ocean in the western Arabian Sea  

E-Print Network [OSTI]

-term in situ measurements. Given the shallow mixed layer, this additional surface heat flux warms the cold of the ocean. The observed relationship between the near-surface winds and mesoscale SSTs generate Ekman pump- ing velocities at the scale of the cold filaments, whose magnitude is the order of 1 m/day in both

Jochum, Markus

30

RSL: A parallel Runtime System Library for regional atmospheric models with nesting  

SciTech Connect (OSTI)

RSL is a parallel runtime system library developed at Argonne National Laboratory that is tailored to regular-grid atmospheric models with mesh refinement in the form of two-way interacting nested grids. RSL provides high-level stencil and interdomain communication, irregular domain decomposition, automatic local/global index translation, distributed I/O, and dynamic load balancing. RSL was used with Fortran90 to parallelize a well-known and widely used regional weather model, the Penn State/NCAR Mesoscale model.

Michalakes, J.G.

1997-08-01T23:59:59.000Z

31

A Regional OceanAtmosphere Model for Eastern Pacific Climate: Toward Reducing Tropical Biases*  

E-Print Network [OSTI]

.5°) of the ROAM enables it to capture mesoscale features, such as tropical instability waves, Central American gap these asymmetric features despite a solar radia- tion forcing at the top of the atmosphere that is zonally uniform

Wang, Yuqing

32

Impact of Agricultural Practice on Regional Climate in a CoupledLand Surface Mesoscale Model  

SciTech Connect (OSTI)

The land surface has been shown to form strong feedbacks with climate due to linkages between atmospheric conditions and terrestrial ecosystem exchanges of energy, momentum, water, and trace gases. Although often ignored in modeling studies, land management itself may form significant feedbacks. Because crops are harvested earlier under drier conditions, regional air temperature, precipitation, and soil moisture, for example, affect harvest timing, particularly of rain-fed crops. This removal of vegetation alters the land surface characteristics and may, in turn, affect regional climate. We applied a coupled climate(MM5) and land-surface (LSM1) model to examine the effects of early and late winter wheat harvest on regional climate in the Department of Energy Atmospheric Radiation Measurement (ARM) Climate Research Facility in the Southern Great Plains, where winter wheat accounts for 20 percent of the land area. Within the winter wheat region, simulated 2 m air temperature was 1.3 C warmer in the Early Harvest scenario at mid-day averaged over the two weeks following harvest. Soils in the harvested area were drier and warmer in the top 10 cm and wetter in the 10-20 cm layer. Midday soils were 2.5 C warmer in the harvested area at mid-day averaged over the two weeks following harvest. Harvest also dramatically altered latent and sensible heat fluxes. Although differences between scenarios diminished once both scenarios were harvested, the short-term impacts of land management on climate were comparable to those from land cover change demonstrated in other studies.

Cooley, H.S.; Riley, W.J.; Torn, M.S.; He, Y.

2004-07-01T23:59:59.000Z

33

atmosphere boundary layer: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Atmospheric Boundary Layer Wind Response to Mesoscale Sea Surface Temperature The wind speed response to mesoscale SST variability is investigated over the Agulhas Return Current...

34

atmospheric superficial layer: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Atmospheric Boundary Layer Wind Response to Mesoscale Sea Surface Temperature The wind speed response to mesoscale SST variability is investigated over the Agulhas Return Current...

35

atmospheric boundary layer: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Atmospheric Boundary Layer Wind Response to Mesoscale Sea Surface Temperature The wind speed response to mesoscale SST variability is investigated over the Agulhas Return Current...

36

atmospheric boundary layers: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Atmospheric Boundary Layer Wind Response to Mesoscale Sea Surface Temperature The wind speed response to mesoscale SST variability is investigated over the Agulhas Return Current...

37

Atmospheric Chemistry, Modeling, and Biogeochemistry of Mercury  

E-Print Network [OSTI]

Atmospheric Chemistry, Modeling, and Biogeochemistry of Mercury Noelle Eckley Selin *Reprinted from Mercury in the Environment: Pattern and Process (Chapter 5) pp. 73-80 Copyright © 2012 with kind, and Biogeochemistry of Mercury NOELLE ECKLEY SELIN and their distribution in the atmosphere. This includes

38

Transformed shoreline-following horizontal coordinates in a mesoscale model: A sea-land-breeze case study  

SciTech Connect (OSTI)

A hydrostatic and incompressible mesoscale model with transformed horizontal coordinates is presented. The model is applied to study the sea-land-breeze circulation over Rio de La Plata. One of the new coordinates is shoreline-following and the other one is locally quasi-perpendicular to the first one. The original set of equations in the Cartesian coordinates is rewritten in the curvilinear coordinates. This transformation is useful provided that the curvilinear coordinates are close to being orthogonal. The horizontal domain covers 250 km [times] 250 km, and the vertical domain is 2 km deep. To predict the sea-land-breeze circulation the model is integrated over 12 h. The forcing of the model is a cyclic perturbation of the surface temperature. The changes in the wind direction during the day are in good agreement with the observations from six weather stations in the region. The same program code is applied to uniform domains of different resolutions in order to test the coordinate transformation. Results show that the predictions based upon the variable-resolution version resemble ones obtained using high uniform resolution but consume only one-fourth the computer time needed by the latter. Comparison of the vertical velocity patterns predicted by the model to the cumulus clouds distribution observed from satellite images show a very good agreement too. The authors believe that all these results justify the use of the coordinate transformation in this type of model, although further verifications are needed in order to draw more definitive conclusions. 28 refs., 11 figs.

Berri, G.J.; Nunez, M.N. (Universidad de Buenos Aires (Argentina) Pabellon II Ciudad Universitaria, Buenos Aires (Argentina))

1993-05-01T23:59:59.000Z

39

Use of ARM observations and numerical models to determine radiative and latent heating profiles of mesoscale convective systems for general circulation models  

SciTech Connect (OSTI)

This three-year project, in cooperation with Professor Bob Houze at University of Washington, has been successfully finished as planned. Both ARM (the Atmospheric Radiation Measurement Program) data and cloud-resolving model (CRM) simulations were used to identify the water budgets of clouds observed in two international field campaigns. The research results achieved shed light on several key processes of clouds in climate change (or general circulation models), which are summarized below. 1. Revealed the effect of mineral dust on mesoscale convective systems (MCSs) Two international field campaigns near a desert and a tropical coast provided unique data to drive and evaluate CRM simulations, which are TWP-ICE (the Tropical Warm Pool International Cloud Experiment) and AMMA (the African Monsoon Multidisciplinary Analysis). Studies of the two campaign data were contrasted, revealing that much mineral dust can bring about large MCSs via ice nucleation and clouds. This result was reported as a PI presentation in the 3rd ASR Science Team meeting held in Arlington, Virginia in March 2012. A paper on the studies was published in the Journal of the Atmospheric Sciences (Zeng et al. 2013). 2. Identified the effect of convective downdrafts on ice crystal concentration Using the large-scale forcing data from TWP-ICE, ARM-SGP (the Southern Great Plains) and other field campaigns, Goddard CRM simulations were carried out in comparison with radar and satellite observations. The comparison between model and observations revealed that convective downdrafts could increase ice crystal concentration by up to three or four orders, which is a key to quantitatively represent the indirect effects of ice nuclei, a kind of aerosol, on clouds and radiation in the Tropics. This result was published in the Journal of the Atmospheric Sciences (Zeng et al. 2011) and summarized in the DOE/ASR Research Highlights Summaries (see http://www.arm.gov/science/highlights/RMjY5/view). 3. Used radar observations to evaluate model simulations In cooperation with Profs. Bob Houze at University of Washington and Steven Rutledge at Colorado State University, numerical model results were evaluated with observations from W- and C-band radars and CloudSat/TRMM satellites. These studies exhibited some shortcomings of current numerical models, such as too little of thin anvil clouds, directing the future improvement of cloud microphysics parameterization in CRMs. Two papers of Powell et al (2012) and Zeng et al. (2013), summarizing these studies, were published in the Journal of the Atmospheric Sciences. 4. Analyzed the water budgets of MCSs Using ARM data from TWP-ICE, ARM-SGP and other field campaigns, the Goddard CRM simulations were carried out to analyze the water budgets of clouds from TWP-ICE and AMMA. The simulations generated a set of datasets on clouds and radiation, which are available http://cloud.gsfc.nasa.gov/. The cloud datasets were available for modelers and other researchers aiming to improve the representation of cloud processes in multi-scale modeling frameworks, GCMs and climate models. Special datasets, such as 3D cloud distributions every six minutes for TWP-ICE, were requested and generated for ARM/ASR investigators. Data server records show that 86,206 datasets were downloaded by 120 users between April of 2010 and January of 2012. 5. MMF simulations The Goddard MMF (multi-scale modeling framework) has been improved by coupling with the Goddard Land Information System (LIS) and the Goddard Earth Observing System Model, Version 5 (GOES5). It has also been optimized on NASA HEC supercomputers and can be run over 4000 CPUs. The improved MMF with high horizontal resolution (1 x 1 degree) is currently being applied to cases covering 2005 and 2006. The results show that the spatial distribution pattern of precipitation rate is well simulated by the MMF through comparisons with satellite retrievals from the CMOPRH and GPCP data sets. In addition, the MMF results were compared with three reanalyses (MERRA, ERA-Interim and CFSR). Although the MMF tends

Tao, Wei-Kuo; Houze, Robert, A., Jr.; Zeng, Xiping

2013-03-14T23:59:59.000Z

40

A Community Atmosphere Model with Superparameterized Clouds  

SciTech Connect (OSTI)

In 1999, National Center for Atmospheric Research (NCAR) scientists Wojciech Grabowski and Piotr Smolarkiewicz created a "multiscale" atmospheric model in which the physical processes associated with clouds were represented by running a simple high-resolution model within each grid column of a lowresolution global model. In idealized experiments, they found that the multiscale model produced promising simulations of organized tropical convection, which other models had struggled to produce. Inspired by their results, Colorado State University (CSU) scientists Marat Khairoutdinov and David Randall created a multiscale version of the Community Atmosphere Model (CAM). They removed the cloud parameterizations of the CAM, and replaced them with Khairoutdinov's high-resolution cloud model. They dubbed the embedded cloud model a "super-parameterization," and the modified CAM is now called the "SP-CAM." Over the next several years, many scientists, from many institutions, have explored the ability of the SP-CAM to simulate tropical weather systems, the day-night changes of precipitation, the Asian and African monsoons, and a number of other climate processes. Cristiana Stan of the Center for Ocean-Land-Atmosphere Interactions found that the SP-CAM gives improved results when coupled to an ocean model, and follow-on studies have explored the SP-CAM's utility when used as the atmospheric component of the Community Earth System Model. Much of this research has been performed under the auspices of the Center for Multiscale Modeling of Atmospheric Processes, a National Science Foundation (NSF) Science and Technology Center for which the lead institution is CSU.

Randall, David; Branson, Mark; Wang, Minghuai; Ghan, Steven J.; Craig, Cheryl; Gettelman, A.; Edwards, Jim

2013-06-18T23:59:59.000Z

Note: This page contains sample records for the topic "atmospheric mesoscale model" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Adjoint modeling for atmospheric pollution process sensitivity at regional scale  

E-Print Network [OSTI]

Adjoint modeling for atmospheric pollution process sensitivity at regional scale Laurent Menut; 0345 Atmospheric Composition and Structure: Pollution--urban and regional (0305); 3210 Mathematical: atmospheric pollution, tropospheric ozone, urban pollution peaks, adjoint modeling, sensitivity Citation

Menut, Laurent

42

Self-Assembly of Mesoscale Isomers: The Role of Pathways and Degrees of Freedom  

E-Print Network [OSTI]

Self-Assembly of Mesoscale Isomers: The Role of Pathways and Degrees of Freedom Shivendra Pandey1 geometric path sampling and a mesoscale experimental model to investigate the self-assembly of a model. Citation: Pandey S, Johnson D, Kaplan R, Klobusicky J, Menon G, et al. (2014) Self-Assembly of Mesoscale

Menon, Govind

43

Development and validation of a vertically two-dimensional mesoscale numerical model  

E-Print Network [OSTI]

because the model is dry. The equations are as follows: dv " ? 1 1 d dv f k X V ? ? Vp ? g Vz + ? ~ ? (pK ? ), (2) dt P pH ds m ds pgH do dn d o + 'it ~ pV + ? (ns) + p V ~ VH = 0 dt ds P H (4) dT . H Q sg ? + d t C p C p pRT The symbols... of the model. The remaining variables have been previously defined. 15 The finite difference equations are as follows: ~ H (o V (i, k) = H(i+1) * ( p(i+1, k) + p(i, k) ) * u(i+1, k) ? H(i) * ( p(i, k) + p (i-l, k) ) * u(i, k) / ( 2 a DX ) = DV(i k) (I...

Walters, Michael Kent

2012-06-07T23:59:59.000Z

44

Modeling atmospheric deposition using a stochastic transport model  

SciTech Connect (OSTI)

An advanced stochastic transport model has been modified to include the removal mechanisms of dry and wet deposition. Time-dependent wind and turbulence fields are generated with a prognostic mesoscale numerical model and are used to advect and disperse individually released particles that are each assigned a mass. These particles are subjected to mass reduction in two ways depending on their physical location. Particles near the surface experience a decrease in mass using the concept of a dry deposition velocity, while the mass of particles located within areas of precipitation are depleted using a scavenging coefficient. Two levels of complexity are incorporated into the particle model. The simple case assumes constant values of dry deposition velocity and scavenging coefficient, while the more complex case varies the values according to meteorology, surface conditions, release material, and precipitation intensity. Instantaneous and cumulative dry and wet deposition are determined from the mass loss due to these physical mechanisms. A useful means of validating the model results is with data available from a recent accidental release of Cesium-137 from a steel-processing furnace in Algeciras, Spain in May, 1998. This paper describes the deposition modeling technique, as well as a comparison of simulated concentration and deposition with measurements taken for the Algeciras release.

Buckley, R.L.

1999-12-17T23:59:59.000Z

45

Silicon Micromachined Dimensional Calibration Artifact for Mesoscale...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Micromachined Dimensional Calibration Artifact for Mesoscale Measurement Machines 1 Silicon Micromachined Dimensional Calibration Artifact for Mesoscale Measurement Machines 2...

46

Atmospheric model intercomparison project: Monsoon simulations  

SciTech Connect (OSTI)

The simulation of monsoons, in particular the Indian summer monsoon, has proven to be a critical test of a general circulation model`s ability to simulate tropical climate and variability. The Monsoon Numerical Experimentation Group has begun to address questions regarding the predictability of monsoon extremes, in particular conditions associated with El Nino and La Nina conditions that tend to be associated with drought and flood conditions over the Indian subcontinent, through a series of seasonal integrations using analyzed initial conditions from successive days in 1987 and 1988. In this paper the authors present an analysis of simulations associated with the Atmospheric Model Intercomparison Project (AMIP), a coordinated effort to simulate the 1979--1988 decade using standardized boundary conditions with approximately 30 atmospheric general circulation models. The 13 models analyzed to date are listed. Using monthly mean data from these simulations they have calculated indices of precipitation and wind shear in an effort to access the performance of the models over the course of the AMIP decade.

Sperber, K.R. [Lawrence Livermore National Lab., CA (United States). Program for Climate Model Diagnosis and Intercomparison; Palmer, T.N. [European Centre for Medium-Range Weather Forecasts, Reading (United Kingdom)

1994-06-01T23:59:59.000Z

47

Atmospheric transmittance model for photosynthetically active radiation  

SciTech Connect (OSTI)

A parametric model of the atmospheric transmittance in the PAR band is presented. The model can be straightforwardly applied for calculating the beam, diffuse and global components of the PAR solar irradiance. The required inputs are: air pressure, ozone, water vapor and nitrogen dioxide column content, ngstrm's turbidity coefficient and single scattering albedo. Comparison with other models and ground measured data shows a reasonable level of accuracy for this model, making it suitable for practical applications. From the computational point of view the calculus is condensed into simple algebra which is a noticeable advantage. For users interested in speed-intensive computation of the effective PAR solar irradiance, a PC program based on the parametric equations along with a user guide are available online at http://solar.physics.uvt.ro/srms.

Paulescu, Marius; Stefu, Nicoleta; Gravila, Paul; Paulescu, Eugenia; Boata, Remus; Pacurar, Angel; Mares, Oana [Physics Department, West University of Timisoara, V Parvan 4, 300223 Timisoara (Romania); Pop, Nicolina [Department of Physical Foundations of Engineering, Politehnica University of Timisoara, V Parvan 2, 300223 Timisoara (Romania); Calinoiu, Delia [Mechanical Engineering Faculty, Politehnica University of Timisoara, Mihai Viteazu 1, 300222 Timisoara (Romania)

2013-11-13T23:59:59.000Z

48

Singular Vector Analysis for Atmospheric Chemical Transport Models  

E-Print Network [OSTI]

are presented for a simulation of atmospheric pollution in East Asia in March 2001. The singular valuesSingular Vector Analysis for Atmospheric Chemical Transport Models Wenyuan Liao and Adrian Sandu for atmospheric chemical transport models. The distinguishing feature of these models is the presence of stiff

Sandu, Adrian

49

Mesoscale Eddy Energy Locality in an Idealized Ocean Model IAN GROOMS, LOUIS-PHILIPPE NADEAU, AND K. SHAFER SMITH  

E-Print Network [OSTI]

. SHAFER SMITH Center for Atmosphere Ocean Science, Courant Institute of Mathematical Sciences, New York

Smith, K. Shafer

50

Top-down estimate of anthropogenic emission inventories and their interannual variability in Houston using a mesoscale inverse modeling technique  

SciTech Connect (OSTI)

The 2000 and 2006 Texas Air Quality Study (TexAQS 2000 and 2006) field campaigns took place in eastern Texas in August-October of 2000 and 2006. Several flights of the National Oceanic and Atmospheric Administration (NOAA) and National Center for Atmospheric Research (NCAR) research aircraft were dedicated to characterizing anthropogenic emissions over Houston. Houston is known for having serious problems with non-attainment of air quality standards. We present a method that uses three models and aircraft observations to assess and improve existing emission inventories using an inverse modeling technique. We used 3-dimensional and 4-dimensional variational (3D-VAR and 4D-VAR) inverse modeling techniques based on a least-squares method to improve the spatial and temporal distribution of CO, NOy (sum of all reactive nitrogen compounds), and SO2 emissions predicted by the 4-km-resolution U.S. Environmental Protection Agency (EPA) National Emission Inventory (NEI) for 2005. Differences between the prior and posterior inventories are discussed in detail. We found that in 2006 the prior daytime emissions in the urban area of Houston have to be reduced by 40% {+-} 12% for CO and 7% {+-} 13% for NOy. Over the Houston Ship Channel, where industrial emissions are predominant, the prior emissions have to be reduced by 41% {+-} 15% for CO and 51% {+-} 9% for NOy. Major ports around Houston have their NOy emissions reduced as well, probably due to uncertainties in near-shore ship emissions in the EPA NEI inventory. Using the measurements from the two field campaigns, we assessed the interannual emission variability between 2000 and 2006. Daytime CO emissions from the Houston urban area have been reduced by 8% {+-} 20%, while the NOy emissions have increased by 20% {+-} 12% from 2000 to 2006. In the Houston Ship Channel, the daytime NOy emissions have increased by 13% {+-} 17%. Our results show qualitative consistencies with known changes in Houston emissions sources.

Brioude, J.; Kim, S. W.; Angevine, Wayne M.; Frost, G. J.; Lee, S. H.; McKeen, S. A.; Trainer, Michael; Fehsenfeld, Fred C.; Holloway, J. S.; Ryerson, T. B.; Williams, E. J.; Petron, Gabrielle; Fast, Jerome D.

2011-10-31T23:59:59.000Z

51

Use of ARM observations and numerical models to determine radiative and latent heating profiles of mesoscale convective systems for general circulation models  

SciTech Connect (OSTI)

We examined cloud radar data in monsoon climates, using cloud radars at Darwin in the Australian monsoon, on a ship in the Bay of Bengal in the South Asian monsoon, and at Niamey in the West African monsoon. We followed on with a more in-depth study of the continental MCSs over West Africa. We investigated whether the West African anvil clouds connected with squall line MCSs passing over the Niamey ARM site could be simulated in a numerical model by comparing the observed anvil clouds to anvil structures generated by the Weather Research and Forecasting (WRF) mesoscale model at high resolution using six different ice-phase microphysical schemes. We carried out further simulations with a cloud-resolving model forced by sounding network budgets over the Niamey region and over the northern Australian region. We have devoted some of the effort of this project to examining how well satellite data can determine the global breadth of the anvil cloud measurements obtained at the ARM ground sites. We next considered whether satellite data could be objectively analyzed to so that their large global measurement sets can be systematically related to the ARM measurements. Further differences were detailed between the land and ocean MCS anvil clouds by examining the interior structure of the anvils with the satellite-detected the CloudSat Cloud Profiling Radar (CPR). The satellite survey of anvil clouds in the Indo-Pacific region was continued to determine the role of MCSs in producing the cloud pattern associated with the MJO.

Houze, Jr., Robert A. [University of Washington Dept. of Atmospheric Sciences

2013-11-13T23:59:59.000Z

52

Mesoscale hybrid calibration artifact  

DOE Patents [OSTI]

A mesoscale calibration artifact, also called a hybrid artifact, suitable for hybrid dimensional measurement and the method for make the artifact. The hybrid artifact has structural characteristics that make it suitable for dimensional measurement in both vision-based systems and touch-probe-based systems. The hybrid artifact employs the intersection of bulk-micromachined planes to fabricate edges that are sharp to the nanometer level and intersecting planes with crystal-lattice-defined angles.

Tran, Hy D. (Albuquerque, NM); Claudet, Andre A. (Albuquerque, NM); Oliver, Andrew D. (Waltham, MA)

2010-09-07T23:59:59.000Z

53

MESOSCALE SIMULATIONS OF POWDER COMPACTION  

SciTech Connect (OSTI)

Mesoscale 3D simulations of shock compaction of metal and ceramic powders have been performed with an Eulerian hydrocode GEODYN. The approach was validated by simulating a well-characterized shock compaction experiment of a porous ductile metal. Simulation results using the Steinberg material model and handbook values for solid 2024 aluminum showed good agreement with experimental compaction curves and wave profiles. Brittle ceramic materials are not as well studied as metals, so a simple material model for solid ceramic (tungsten carbide) has been calibrated to match experimental compaction curves. Direct simulations of gas gun experiments with ceramic powders have been performed and showed good agreement with experimental data. The numerical shock wave profile has same character and thickness as that measured experimentally using VISAR. The numerical results show reshock states above the single-shock Hugoniot line as observed in experiments. We found that for good quantitative agreement with experiments 3D simulations are essential.

Lomov, Ilya; Fujino, Don; Antoun, Tarabay; Liu, Benjamin [Lawrence Livermore National Laboratory, P. O. Box 808, Livermore CA 94551 (United States)

2009-12-28T23:59:59.000Z

54

Targeted Observations for Atmospheric Chemistry and Transport Models  

E-Print Network [OSTI]

for a simulation of atmospheric pollution in East Asia in March 2001 show that the optimal location of observations, targeted observations. 1 Introduction Our ability to anticipate and manage changes in atmospheric pollutantTargeted Observations for Atmospheric Chemistry and Transport Models Adrian Sandu Department

Sandu, Adrian

55

Modeling decade to century scale variability in the atmosphere/ocean [Final report  

SciTech Connect (OSTI)

Study of the intrinsic variability of a coupled atmosphere/ocean model called The Fast Ocean/Atmosphere Model (FOAM).

Kutzbach, John E.

2002-02-04T23:59:59.000Z

56

Momentum transport processes in the stratiform regions of mesoscale convective systems over the western Pacific warm pool  

E-Print Network [OSTI]

Momentum transport by the stratiform components of mesoscale convective systems (MCSs) during the Tropical OceanGlobal Atmosphere Coupled OceanAtmosphere Response Experiment in December 1992 is investigated using a ...

Mechem, David B.; Chen, Shuyi S.; Houze, Robert A. Jr.

2006-04-01T23:59:59.000Z

57

Development of an Adjoint for a Complex Atmospheric Model, the ARPS, using TAF  

E-Print Network [OSTI]

, such as operational weather predictions models, pose challenges on the applicability of AD tools. We report- ational weather prediction models are much more complex, and the problem sizes tend to be much larger as a system for mesoscale and storm-scale numerical weather prediction as well as a wide range of idealized

Gao, Jidong

58

Mesoscale Dynamics Spring Semester 2014  

E-Print Network [OSTI]

ATS 735 Mesoscale Dynamics (3 cr) Spring Semester 2014 Instructor: Richard H. Johnson, Room ATS 305, certain topics in mesoscale dynamics may be emphasized more than others. Although basic concepts lectures on some of the topics. Several books that are relevant to the course are: Cloud Dynamics, 1993 (R

59

Chapter 8: Modelling Sediment Records of Atmospherically Deposited Contaminants  

E-Print Network [OSTI]

73 Chapter 8: Modelling Sediment Records of Atmospherically Deposited Contaminants 8.1. Catchment the Water Column...............................................79 8.3 Water Column to Bottom Sediment Transfer......................................80 #12;Chapter 8: Modelling Sediment Records... 74 8

Short, Daniel

60

White Dwarf Spectra and Atmosphere Models  

E-Print Network [OSTI]

We describe the spectral classification of white dwarfs and some of the physical processes important for their understanding. In the major part of this paper we discuss the input physics and computational methods for one of the most widely used stellar atmosphere codes for white dwarfs.

Detlev Koester

2008-12-02T23:59:59.000Z

Note: This page contains sample records for the topic "atmospheric mesoscale model" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Interactive Visualization of Modeled Atmospheric Trace Constituents Carmen M. Benkovitz  

E-Print Network [OSTI]

the effects of the emissions of Popocatepetl volcano, located near Mexico City. The effects of stronger of the Brookhaven National Laboratory Chemical Transport Model (CTM) of sulfate in the atmosphere. The visualization on climate. Anthropogenic activities affect the aerosol content of the atmosphere. Anthropogenic emissions

62

Atmospheric Modelling of Greenhouse Gases and Air Quality  

E-Print Network [OSTI]

. Increase in mixing height (h) entrains (draws in) air from above the box #12Atmospheric Modelling of Greenhouse Gases and Air Quality John C. Lin Courtenay Strong University of Utah: February 20th, 2013 Department of Atmospheric Sciences University of Utah #12;Outline ·CO2 ó Air

Tipple, Brett

63

On Adaptive Mesh Refinement for Atmospheric Pollution Models  

E-Print Network [OSTI]

On Adaptive Mesh Refinement for Atmospheric Pollution Models Emil M. Constantinescu and Adrian res- olution system for modeling regional air pollution based on the chemical transport model STEM. Keywords: Air Pollution Modeling, Adaptive Mesh Refinement. 1 Introduction Inadequate grid resolution can

Sandu, Adrian

64

Computer support to run models of the atmosphere. Final report  

SciTech Connect (OSTI)

This research is focused on a better quantification of the variations in CO{sub 2} exchanges between the atmosphere and biosphere and the factors responsible for these exchangers. The principal approach is to infer the variations in the exchanges from variations in the atmospheric CO{sub 2} distribution. The principal tool involves using a global three-dimensional tracer transport model to advect and convect CO{sub 2} in the atmosphere. The tracer model the authors used was developed at the Goddard institute for Space Studies (GISS) and is derived from the GISS atmospheric general circulation model. A special run of the GCM is made to save high-frequency winds and mixing statistics for the tracer model.

Fung, I.

1996-08-30T23:59:59.000Z

65

Sensitivity of mesoscale gravity waves to the baroclinicity of jet-front systems  

E-Print Network [OSTI]

To investigate the generation of mesoscale gravity waves from upper-tropospheric jet-front systems, five different life cycles of baroclinic waves are simulated with a high-resolution mesoscale model (MM5 with 10-km grid spacing). The baroclinicity...

Wang, Shuguang

2006-04-12T23:59:59.000Z

66

E-Print Network 3.0 - atmosphere model description Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

coupling software Summary: linking the main model components of present-day Earth System models (ESMs), i.e. the atmosphere... be followed to couple ocean and atmosphere...

67

E-Print Network 3.0 - atmosphere model version Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

coupling software Summary: linking the main model components of present-day Earth System models (ESMs), i.e. the atmosphere... be followed to couple ocean and atmosphere...

68

E-Print Network 3.0 - atmospheric models final Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

coupling software Summary: linking the main model components of present-day Earth System models (ESMs), i.e. the atmosphere... be followed to couple ocean and atmosphere...

69

E-Print Network 3.0 - atmosphere model validation Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

coupling software Summary: linking the main model components of present-day Earth System models (ESMs), i.e. the atmosphere... be followed to couple ocean and atmosphere...

70

E-Print Network 3.0 - atmospheric diffusion models Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

coupling software Summary: linking the main model components of present-day Earth System models (ESMs), i.e. the atmosphere... be followed to couple ocean and atmosphere...

71

Modeling of Alpine Atmospheric Dynamics II  

E-Print Network [OSTI]

for large mesh sizes (x 20 km) to vertically redistribute heat and moisture in a grid column when model in a numerical model Convective cloud systems are not resolved if the mesh size of the grid is larger than small to treat convection as sub-grid scale process but too large to treat it explicitly For example

Gohm, Alexander

72

Acoustic Characterization of Mesoscale Objects  

SciTech Connect (OSTI)

This report describes the science and engineering performed to provide state-of-the-art acoustic capabilities for nondestructively characterizing mesoscale (millimeter-sized) objects--allowing micrometer resolution over the objects entire volume. Materials and structures used in mesoscale objects necessitate the use of (1) GHz acoustic frequencies and (2) non-contacting laser generation and detection of acoustic waves. This effort demonstrated that acoustic methods at gigahertz frequencies have the necessary penetration depth and spatial resolution to effectively detect density discontinuities, gaps, and delaminations. A prototype laser-based ultrasonic system was designed and built. The system uses a micro-chip laser for excitation of broadband ultrasonic waves with frequency components reaching 1.0 GHz, and a path-stabilized Michelson interferometer for detection. The proof-of-concept for mesoscale characterization is demonstrated by imaging a micro-fabricated etched pattern in a 70 {micro}m thick silicon wafer.

Chinn, D; Huber, R; Chambers, D; Cole, G; Balogun, O; Spicer, J; Murray, T

2007-03-13T23:59:59.000Z

73

Mesoscale Modeling and Validation of Texture Evolution during Asymmetric Rooling and Static Recrystallization of Magnesium Alloy AZ31B  

SciTech Connect (OSTI)

The focus of the present research is to develop an integrated deformation and recrystallization model for magnesium alloys at the microstructural length scale. It is known that in magnesium alloys nucleation of recrystallized grains occurs at various microstructural inhomogeneities such as twins and localized deformation bands. However, there is a need to develop models that can predict the evolution of the grain structure and texture developed during recrystallization and grain growth, especially when the deformation process follows a complicated deformation path such as in asymmetric rolling. The deformation model is based on a crystal plasticity approach implemented at the length scale of the microstructure that includes deformation mechanisms based on dislocation slip and twinning. The recrystallization simulation is based on a Monte Carlo technique that operates on the output of the deformation simulations. The nucleation criterion during recrystallization is based on the local stored energy and the Monte Carlo technique is used to simulate the growth of the nuclei due to local stored energy differences and curvature. The model predictions are compared with experimental data obtained through electron backscatter analysis and neutron diffraction.

Radhakrishnan, Balasubramaniam [ORNL; Gorti, Sarma B [ORNL; Stoica, Grigoreta M [ORNL; Muralidharan, Govindarajan [ORNL; Stoica, Alexandru Dan [ORNL; Wang, Xun-Li [ORNL; Specht, Eliot D [ORNL; Kenik, Edward A [ORNL; Muth, Thomas R [ORNL

2012-01-01T23:59:59.000Z

74

Using Neural Networks Atmospheric Model Physics  

E-Print Network [OSTI]

Outline · Background ­ GCM · Radiation · Convection ­ Neural Networks · NN Emulations of Existing Model · Major components of P = {R, W, C, T, S, CH}: ­ R - radiation (long & short wave processes): AER Inc ­ S ­ land, ocean, ice ­ air interaction ­ CH ­ chemistry (aerosols) · Components of P are 1-D

Anisimov, Mikhail

75

Modeled atmospheric radon concentrations from uranium mines  

SciTech Connect (OSTI)

Uranium mining and milling operations result in the release of radon from numerous sources of various types and strengths. The US Environmental Protection Agency (EPA) under the Clean Air Act, is assessing the health impact of air emissions of radon from underground uranium mines. In this case, the radon emissions may impact workers and residents in the mine vicinity. To aid in this assessment, the EPA needs to know how mine releases can affect the radon concentrations at populated locations. To obtain this type of information, Pacific Northwest Laboratory used the radon emissions, release characteristics and local meterological conditions for a number of mines to model incremental radon concentrations. Long-term, average, incremental radon concentrations were computed based on the best available information on release rates, plume rise parameters, number and locations of vents, and local dispersion climatology. Calculations are made for a model mine, individual mines, and multiple mines. Our approach was to start with a general case and then consider specific cases for comparison. A model underground uranium mine was used to provide definition of the order of magnitude of typical impacts. Then computations were made for specific mines using the best mine-specific information available for each mine. These case study results are expressed as predicted incremental radon concentration contours plotted on maps with local population data from a previous study. Finally, the effect of possible overlap of radon releases from nearby mines was studied by calculating cumulative radon concentrations for multiple mines in a region with many mines. The dispersion model, modeling assumptions, data sources, computational procedures, and results are documented in this report. 7 refs., 27 figs., 18 tabs.

Droppo, J.G.

1985-04-01T23:59:59.000Z

76

Review of structure representation and reconstruction on mesoscale and microscale  

SciTech Connect (OSTI)

Structure representation and reconstruction on mesoscale and microscale is critical in material design, advanced manufacturing and multiscale modeling. Microstructure reconstruction has been applied in different areas of materials science and technology, structural materials, energy materials, geology, hydrology, etc. This review summarizes the microstructure descriptors and formulations used to represent and algorithms to reconstruct structures at microscale and mesoscale. In the stochastic methods using correlation function, different optimization approaches have been adapted for objective function minimization. A variety of reconstruction approaches are compared in efficiency and accuracy.

Li, Dongsheng

2014-05-01T23:59:59.000Z

77

Oxygen line formation in 3D hydrodynamical model atmospheres  

E-Print Network [OSTI]

The formation of [O I], O I and OH lines in metal-poor stars has been studied by means of 3D hydrodynamical model atmospheres. For O I detailed 3D non-LTE calculations have been performed. While the influence of 3D model atmospheres is minor for [O I] and O I lines, the very low temperatures encountered at low metallicities have a drastic impact on the OH lines. As a result, the derived O abundances are found to be systematically overestimated in 1D analyses, casting doubts on the recent claims for a monotonic increase in [O/Fe] towards lower metallicities.

M. Asplund

2000-11-02T23:59:59.000Z

78

E-Print Network 3.0 - atmospheric models testing Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

and Tectonics (COMET) Collection: Geosciences 7 BTRAM: An Interactive Atmospheric Radiative Transfer Model I.M. Chapman1 Summary: BTRAM: An Interactive Atmospheric Radiative...

79

E-Print Network 3.0 - atmospheric test models Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

and Tectonics (COMET) Collection: Geosciences 7 BTRAM: An Interactive Atmospheric Radiative Transfer Model I.M. Chapman1 Summary: BTRAM: An Interactive Atmospheric Radiative...

80

Graduate Opportunities in Atmospheric Modeling to Understand Greenhouse Gas Emissions  

E-Print Network [OSTI]

Graduate Opportunities in Atmospheric Modeling to Understand Greenhouse Gas Emissions University://www.atmos.utah.edu/) seeks multiple graduate students to study greenhouse gas emissions associated with urban development greenhouse gas emissions. Samples of guiding questions as part of the projects include: · What can explain

Lin, John Chun-Han

Note: This page contains sample records for the topic "atmospheric mesoscale model" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Meso-scale machining capabilities and issues  

SciTech Connect (OSTI)

Meso-scale manufacturing processes are bridging the gap between silicon-based MEMS processes and conventional miniature machining. These processes can fabricate two and three-dimensional parts having micron size features in traditional materials such as stainless steels, rare earth magnets, ceramics, and glass. Meso-scale processes that are currently available include, focused ion beam sputtering, micro-milling, micro-turning, excimer laser ablation, femto-second laser ablation, and micro electro discharge machining. These meso-scale processes employ subtractive machining technologies (i.e., material removal), unlike LIGA, which is an additive meso-scale process. Meso-scale processes have different material capabilities and machining performance specifications. Machining performance specifications of interest include minimum feature size, feature tolerance, feature location accuracy, surface finish, and material removal rate. Sandia National Laboratories is developing meso-scale electro-mechanical components, which require meso-scale parts that move relative to one another. The meso-scale parts fabricated by subtractive meso-scale manufacturing processes have unique tribology issues because of the variety of materials and the surface conditions produced by the different meso-scale manufacturing processes.

BENAVIDES,GILBERT L.; ADAMS,DAVID P.; YANG,PIN

2000-05-15T23:59:59.000Z

82

A Grid of 3D Stellar Atmosphere Models of Solar Metallicity: I. General Properties, Granulation and Atmospheric Expansion  

E-Print Network [OSTI]

Present grids of stellar atmosphere models are the workhorses in interpreting stellar observations, and determining their fundamental parameters. These models rely on greatly simplified models of convection, however, lending less predictive power to such models of late type stars. We present a grid of improved and more reliable stellar atmosphere models of late type stars, based on deep, 3D, convective, stellar atmosphere simulations. This grid is to be used in general for interpreting observations, and improve stellar and asteroseismic modeling. We solve the Navier Stokes equations in 3D and concurrent with the radiative transfer equation, for a range of atmospheric parameters, covering most of stellar evolution with convection at the surface. We emphasize use of the best available atomic physics for quantitative predictions and comparisons with observations. We present granulation size, convective expansion of the acoustic cavity, asymptotic adiabat, as function of atmospheric parameters. These and other re...

Trampedach, Regner; Collet, Remo; Nordlund, ke; Stein, Robert F

2013-01-01T23:59:59.000Z

83

ARCHITECTURE OF THE MERCURY MESOSCALE METEOROLOGICAL DATA FUSION C. Fields, C. Cavendish, M. Coombs, T. Eskridge, R. Hartley, H. Pfeiffer, and C. Soderlund  

E-Print Network [OSTI]

ARCHITECTURE OF THE MERCURY MESOSCALE METEOROLOGICAL DATA FUSION C. Fields, C. Cavendish, M. Coombs Atmospheric Sciences Laboratory White Sands Missile Range, NM 88002-5501 USA 1. INTRODUCTION The MERCURY) that require meteorological data as input (McWilliams or al., this volume). MERCURY addresses, at the mesoscale

Hartley, Roger

84

Closing the Mesoscale Gap  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation Proposed New SubstationClean Communities of WesternVailCloistered JuneLabClosest TypeClosing

85

Atmospheric Climate Model Experiments Performed at Multiple Horizontal Resolutions  

SciTech Connect (OSTI)

This report documents salient features of version 3.3 of the Community Atmosphere Model (CAM3.3) and of three climate simulations in which the resolution of its latitude-longitude grid was systematically increased. For all these simulations of global atmospheric climate during the period 1980-1999, observed monthly ocean surface temperatures and sea ice extents were prescribed according to standard Atmospheric Model Intercomparison Project (AMIP) values. These CAM3.3 resolution experiments served as control runs for subsequent simulations of the climatic effects of agricultural irrigation, the focus of a Laboratory Directed Research and Development (LDRD) project. The CAM3.3 model was able to replicate basic features of the historical climate, although biases in a number of atmospheric variables were evident. Increasing horizontal resolution also generally failed to ameliorate the large-scale errors in most of the climate variables that could be compared with observations. A notable exception was the simulation of precipitation, which incrementally improved with increasing resolution, especially in regions where orography plays a central role in determining the local hydroclimate.

Phillips, T; Bala, G; Gleckler, P; Lobell, D; Mirin, A; Maxwell, R; Rotman, D

2007-12-21T23:59:59.000Z

86

Modeling the atmospheric inputs of MTBE to groundwater systems  

SciTech Connect (OSTI)

A numerical transport model was used to calculate the movement of methyl-t-butyl ether (MTBE) and several other volatile organic compounds (VOCs) from the atmosphere downward through the unsaturated zone and into shallow groundwater. Simulations were carried out for periods as long as 10 years to investigate whether a gaseous atmospheric MTBE source at typical ambient concentrations could account for the presence of MTBE in shallow groundwater at the types of low ug/L levels that have been found during the National Water Quality Assessment Program currently being conducted by the US Geological Survey. The simulations indicate that downward movement of MTBE to shallow groundwater will be very slow when there is no net downward movement of water through the vadose zone. For example, for a vadose zone composed of fine sand, and assuming tens of cm of infiltration, then only a few years will be required for water at a water table that is 5.0 m below ground surface to attain MTBE levels that correspond to saturation with respect to the atmospheric source gaseous concentration. An on/off atmospheric source, as might occur in the seasonal use of MTBE, will lead to concentrations in shallow groundwater that correspond to saturation with the time-averaging atmospheric source concentration.

Pankow, J.F.; Johnson, R.L. [Oregon Graduate Inst., Portland, OR (United States). Dept. of Environmental Science and Engineering; Thomson, N.R. [Univ. of Waterloo, Ontario (Canada). Dept. of Civil Engineering

1995-12-31T23:59:59.000Z

87

Thermal shallow water models of geostrophic turbulence in Jovian atmospheres  

SciTech Connect (OSTI)

Conventional shallow water theory successfully reproduces many key features of the Jovian atmosphere: a mixture of coherent vortices and stable, large-scale, zonal jets whose amplitude decreases with distance from the equator. However, both freely decaying and forced-dissipative simulations of the shallow water equations in Jovian parameter regimes invariably yield retrograde equatorial jets, while Jupiter itself has a strong prograde equatorial jet. Simulations by Scott and Polvani [Equatorial superrotation in shallow atmospheres, Geophys. Res. Lett. 35, L24202 (2008)] have produced prograde equatorial jets through the addition of a model for radiative relaxation in the shallow water height equation. However, their model does not conserve mass or momentum in the active layer, and produces mid-latitude jets much weaker than the equatorial jet. We present the thermal shallow water equations as an alternative model for Jovian atmospheres. These equations permit horizontal variations in the thermodynamic properties of the fluid within the active layer. We incorporate a radiative relaxation term in the separate temperature equation, leaving the mass and momentum conservation equations untouched. Simulations of this model in the Jovian regime yield a strong prograde equatorial jet, and larger amplitude mid-latitude jets than the Scott and Polvani model. For both models, the slope of the non-zonal energy spectra is consistent with the classic Kolmogorov scaling, and the slope of the zonal energy spectra is consistent with the much steeper spectrum observed for Jupiter. We also perform simulations of the thermal shallow water equations for Neptunian parameter values, with a radiative relaxation time scale calculated for the same 25 mbar pressure level we used for Jupiter. These Neptunian simulations reproduce the broad, retrograde equatorial jet and prograde mid-latitude jets seen in observations. The much longer radiative time scale for the colder planet Neptune explains the transition from a prograde to a retrograde equatorial jet, while the broader jets are due to the deformation radius being a larger fraction of the planetary radius.

Warneford, Emma S., E-mail: emma.warneford@maths.ox.ac.uk; Dellar, Paul J., E-mail: dellar@maths.ox.ac.uk [OCIAM, Mathematical Institute, University of Oxford, Radcliffe Observatory Quarter, Oxford OX2 6GG (United Kingdom)

2014-01-15T23:59:59.000Z

88

Regional forecasting with global atmospheric models; Final report  

SciTech Connect (OSTI)

The purpose of the project was to conduct model simulations for past and future climate change with respect to the proposed Yucca Mtn. repository. The authors report on three main topics, one of which is boundary conditions for paleo-hindcast studies. These conditions are necessary for the conduction of three to four model simulations. The boundary conditions have been prepared for future runs. The second topic is (a) comparing the atmospheric general circulation model (GCM) with observations and other GCMs; and (b) development of a better precipitation data base for the Yucca Mtn. region for comparisons with models. These tasks have been completed. The third topic is preliminary assessments of future climate change. Energy balance model (EBM) simulations suggest that the greenhouse effect will likely dominate climate change at Yucca Mtn. for the next 10,000 years. The EBM study should improve rational choice of GCM CO{sub 2} scenarios for future climate change.

Crowley, T.J.; Smith, N.R. [Applied Research Corp., College Station, TX (United States)

1994-05-01T23:59:59.000Z

89

The Soil-Plant-Atmosphere model Manual, version 1.3, September 2005  

E-Print Network [OSTI]

.................................................................................................. 5 Soil energy and water balanceThe Soil-Plant-Atmosphere model Manual, version 1.3, September 2005 Dr. Mathew Williams School handbook v 1.2 -2- Index The Soil-Plant-Atmosphere model

90

Mesoscale Benchmark Demonstration Problem 1: Mesoscale Simulations of Intra-granular Fission Gas Bubbles in UO2 under Post-irradiation Thermal Annealing  

SciTech Connect (OSTI)

A study was conducted to evaluate the capabilities of different numerical methods used to represent microstructure behavior at the mesoscale for irradiated material using an idealized benchmark problem. The purpose of the mesoscale benchmark problem was to provide a common basis to assess several mesoscale methods with the objective of identifying the strengths and areas of improvement in the predictive modeling of microstructure evolution. In this work, mesoscale models (phase-field, Potts, and kinetic Monte Carlo) developed by PNNL, INL, SNL, and ORNL were used to calculate the evolution kinetics of intra-granular fission gas bubbles in UO2 fuel under post-irradiation thermal annealing conditions. The benchmark problem was constructed to include important microstructural evolution mechanisms on the kinetics of intra-granular fission gas bubble behavior such as the atomic diffusion of Xe atoms, U vacancies, and O vacancies, the effect of vacancy capture and emission from defects, and the elastic interaction of non-equilibrium gas bubbles. An idealized set of assumptions was imposed on the benchmark problem to simplify the mechanisms considered. The capability and numerical efficiency of different models are compared against selected experimental and simulation results. These comparisons find that the phase-field methods, by the nature of the free energy formulation, are able to represent a larger subset of the mechanisms influencing the intra-granular bubble growth and coarsening mechanisms in the idealized benchmark problem as compared to the Potts and kinetic Monte Carlo methods. It is recognized that the mesoscale benchmark problem as formulated does not specifically highlight the strengths of the discrete particle modeling used in the Potts and kinetic Monte Carlo methods. Future efforts are recommended to construct increasingly more complex mesoscale benchmark problems to further verify and validate the predictive capabilities of the mesoscale modeling methods used in this study.

Li, Yulan; Hu, Shenyang Y.; Montgomery, Robert; Gao, Fei; Sun, Xin; Tonks, Michael; Biner, Bullent; Millet, Paul; Tikare, Veena; Radhakrishnan, Balasubramaniam; Andersson , David

2012-04-11T23:59:59.000Z

91

Development and testing of parameterizations for continental and tropical ice cloud microphysical and radiative properties in GCM and mesoscale models. Final report  

SciTech Connect (OSTI)

The overall purpose of this research was to exploit measurements in clouds sampled during several field programs, especially from experiments in tropical regions, in a four-component study to develop and validate cloud parameterizations for general circulation models, emphasizing ice clouds. The components were: (1) parameterization of basic properties of mid- and upper-tropospheric clouds, such as condensed water content, primarily with respect to cirrus from tropical areas; (2) the second component was to develop parameterizations which express cloud radiative properties in terms of basic cloud microphysical properties, dealing primarily with tropical oceanic cirrus clouds and continental thunderstorm anvils, but also including altocumulus clouds; (3) the third component was to validate the parameterizations through use of ground-based measurements calibrated using existing and planned in-situ measurements of cloud microphysical properties and bulk radiative properties, as well as time-resolved data collected over extended periods of time; (4) the fourth component was to implement the parameterizations in the National Center for Atmospheric Research (NCAR) community climate model (CCM) II or in the NOAA-GFDL model (by L. Donner GFDL) and to perform sensitivity studies.

Heymsfield, A.

1997-09-01T23:59:59.000Z

92

Poster Sessions J. Dudhia Mesoscale and Microscale Meteorology Division  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 - September 2006PhotovoltaicSeptember 22, 2014SocietyJ. Dudhia Mesoscale and

93

Atmospheric Dispersion Modeling: Challenges of the Fukushima Daiichi Response  

SciTech Connect (OSTI)

The U.S. Department of Energys (DOE) National Atmospheric Release Advisory Center (NARAC) provided a wide range of predictions and analyses as part of the response to the Fukushima Daiichi Nuclear Power Plant accident. This work encompassed: weather forecasts and atmospheric transport predictions, estimates of possible dose in Japan based on hypothetical U.S. Nuclear Regulatory Commission scenarios of potential radionuclide releases, predictions of possible plume arrival times and dose levels at U.S. locations, and source estimation and plume model refinement. An overview of NARAC response activities is provided, along with a more in-depth discussion of some of NARACs preliminary source reconstruction analyses. NARAC optimized the overall agreement of model predictions to dose rate measurements using statistical comparisons of data and model values paired in space and time. Estimated emission rates varied depending on the choice of release assumptions (e.g., time-varying vs. constant release rates), the radionuclide mix, meteorology, and/or the radiological data used in the analysis. Results were found to be consistent with other studies within expected uncertainties, despite the application of different source estimation methodologies and the use of significantly different radiological measurement data. A discussion of some of the operational and scientific challenges encountered during the response, along with recommendations for future work, is provided.

Sugiyama, Gayle [Lawrence Livermore National Laboratory; Nasstrom, John [Lawrence Livermore National Laboratory; Pobanz, Brenda [Lawrence Livermore National Laboratory; Foster, Kevin [Lawrence Livermore National Laboratory; Simpson, Matthew [Lawrence Livermore National Laboratory; Vogt, Phil [Lawrence Livermore National Laboratory; Aluzzi, Fernando [Lawrence Livermore National Laboratory; Homann, Steve [Lawrence Livermore National Laboratory

2012-05-01T23:59:59.000Z

94

Determining Greenland Ice Sheet sensitivity to regional climate change: one-way coupling of a 3-D thermo-mechanical ice sheet model with a mesoscale climate model  

E-Print Network [OSTI]

in running RCMs over Greenland to produce high-qualityoutlet glaciers. For Greenland, this detail is specificallyCurrently, no coupled Greenland Ice Sheet model experiment

Schlegel, Nicole-Jeanne

2011-01-01T23:59:59.000Z

95

E-Print Network 3.0 - atmospheric modeling based Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

coefficient for moisture (4... linking the main model components of present-day Earth System models (ESMs), i.e. the atmosphere... that the exchanges between the ... Source:...

96

Cloud in the operational DWD mesoscale model An extensive documentation of the physics included in the Lokal Modell (LM) can be found  

E-Print Network [OSTI]

in the Lokal Modell (LM) can be found in Doms et al. (2004). Here a short summary of the cloud physics is given-scale clouds Since 26th of April 2004 the Lokal Modell (LM) uses a two-category ice scheme which explicitly S that are considered in this two-category ice scheme of LM. The individual microphysical processes are: Sc condensation

Reading, University of

97

Postulated Mesoscale Quantum of Internal Friction Hysteresis  

E-Print Network [OSTI]

Evidence is provided, from yet another experiment, for the existence of a mesoscale quantum of internal friction hysteresis, having the value of the electron rest energy divided by the fine structure constant.

Randall D. Peters

2004-05-27T23:59:59.000Z

98

Atmospheric component of the MPI-M Earth System Model: Bjorn Stevens,1  

E-Print Network [OSTI]

Atmospheric component of the MPI-M Earth System Model: ECHAM6 Bjorn Stevens,1 Marco Giorgetta,1: Stevens, B., et al. (2013), Atmospheric component of the MPI-M Earth System Model: ECHAM6, J. Adv. Model System Model (or MPI-ESM) is described in an accompanying paper (M. Giorgetta et al., Climate change from

Reichler, Thomas

99

A Grid of FASTWIND NLTE Model Atmospheres of Massive Stars  

E-Print Network [OSTI]

In the last few years our knowledge of the physics of massive stars has improved tremendously. However, further investigations are still needed, especially regarding accurate calibrations of their fundamental parameters. To this end, we have constructed a comprehensive grid of NLTE model atmospheres and corresponding synthetic spectra in the massive star domain. The grid covers the complete B type spectral range, extended to late O on the hot side and early A on the cool side, from supergiants to dwarfs and from weak stellar winds to very strong ones. It has been calculated with the latest version of the FASTWIND code. The analysis of an extensive sample of OB stars in the framework of the COROT space mission will lead to accurate calibrations of effective temperatures, gravities, mass loss rates etc. This paper contains a detailed description of the grid, which has been baptised as BSTAR06 and which will be available for further research in the near future.

K. Lefever; J. Puls; C. Aerts

2006-09-22T23:59:59.000Z

100

Model Wind over the Central and Southern California Coastal Ocean HSIAO-MING HSU  

E-Print Network [OSTI]

Model Wind over the Central and Southern California Coastal Ocean HSIAO-MING HSU National Center of high-resolution wind in coastal ocean modeling. This paper tests the Coupled Ocean­Atmosphere Mesoscale Prediction System (COAMPS) at the 9-, 27-, and 81-km grid resolutions in simulating wind off the central

Note: This page contains sample records for the topic "atmospheric mesoscale model" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

MANHAZ position paper on: Modelling of Pollutant Transport in the Atmosphere  

E-Print Network [OSTI]

MANHAZ position paper on: Modelling of Pollutant Transport in the Atmosphere Torben Mikkelsen July, Denmark I Atmospheric dispersion: Basic The dispersion of pollutants is intimately related to the state 2003 Atmospheric Physics Division Wind Energy Department Risø National Laboratory Dk-4000 Roskilde

102

Spatio-temporal statistical models with applications to atmospheric processes  

SciTech Connect (OSTI)

This doctoral dissertation is presented as three self-contained papers. An introductory chapter considers traditional spatio-temporal statistical methods used in the atmospheric sciences from a statistical perspective. Although this section is primarily a review, many of the statistical issues considered have not been considered in the context of these methods and several open questions are posed. The first paper attempts to determine a means of characterizing the semiannual oscillation (SAO) spatial variation in the northern hemisphere extratropical height field. It was discovered that the midlatitude SAO in 500hPa geopotential height could be explained almost entirely as a result of spatial and temporal asymmetries in the annual variation of stationary eddies. It was concluded that the mechanism for the SAO in the northern hemisphere is a result of land-sea contrasts. The second paper examines the seasonal variability of mixed Rossby-gravity waves (MRGW) in lower stratospheric over the equatorial Pacific. Advanced cyclostationary time series techniques were used for analysis. It was found that there are significant twice-yearly peaks in MRGW activity. Analyses also suggested a convergence of horizontal momentum flux associated with these waves. In the third paper, a new spatio-temporal statistical model is proposed that attempts to consider the influence of both temporal and spatial variability. This method is mainly concerned with prediction in space and time, and provides a spatially descriptive and temporally dynamic model.

Wikle, C.K.

1996-12-31T23:59:59.000Z

103

E-Print Network 3.0 - atmospheric climate model Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

changes in atmospheric condensation nuclei (CN... capabilities of the Earth System Models and reduce ... Source: Knuth, Kevin H. - Department of Physics, State...

104

E-Print Network 3.0 - atmospheric modeling system Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

1, December 2010 draft Summary: is to integrate atmospheric chemistry into Earth System Models (ESMs) that attempt to fully couple the physics... Guy P. Brasseur and Daniel...

105

Manuscript prepared for Geosci. Model Dev.-Date: 28 May 2013 CHIMERE 2013: a model for regional atmospheric composition  

E-Print Network [OSTI]

is dedicated to regional atmospheric pollution event studies. Since it has now reached a certain level atmospheric composition modelling Laurent MENUT1 , Bertrand BESSAGNET2 , Dmitry KHVOROSTYANOV1 , Matthias dell'Aquila, L'Aquila, Italy 6 NCAR Atmospheric Chemistry Division, 3450 Mitchell Lane, Boulder

Menut, Laurent

106

Extended Canadian middle atmosphere model: zonal-mean climatology and  

E-Print Network [OSTI]

and data assimilation; 3334 Meteorology and Atmospheric Dynamics: Middle atmosphere dynamics (0341, 0342 the Upper Atmos- phere Research Satellite (UARS), such as the Wind Imaging Interferometer (WINDII) [Shepherd and Dynamics (TIMED) satellite. These observations have provided (or will provide) a unique set of information

Wirosoetisno, Djoko

107

A MODEL ATMOSPHERE ANALYSIS OF ALPHA AURIGAE A  

SciTech Connect (OSTI)

This work presents the first quantitative composite model atmosphere analysis of Capella, the brightest near-equal-mass spectroscopic binary and principal star of the constellation Auriga. Its high-resolution spectrum leads to a slightly metal-rich object at [Fe/H] = +0.05 {+-} 0.08 dex. In line with its young age and its kinematics, this consistently associates Capella with the Hyades moving group. The measured projected rotational velocities, vsin i{sub Aa} = 3.5 {+-} 0.8 km s{sup -1} and vsin i{sub Ab} = 35.4 {+-} 3.2 km s{sup -1}, both agree with rotational and orbital coplanarity and synchronous orbital rotation for the Aa component. At an orbital period P = 104 d the primary's bound rotation together with the almost zero orbital eccentricity are both key characteristics of this binary and clearly imply that the Aa component must have passed the tip of the giant branch. Whether in that phase Capella also became a mass transfer system remains inconclusive at present, though the high rotational velocity of the less evolved Hertzsprung gap secondary and the very diverse lithium abundances of both its components render this a plausible case.

Fuhrmann, Klaus [Astronomisches Institut, Ruhr-Universitaet Bochum, Universitaetsstrasse 150, D-44780 Bochum (Germany)

2011-11-20T23:59:59.000Z

108

Parameterization of urban sub-grid scale processes in global atmospheric chemistry models  

E-Print Network [OSTI]

-scale models. (submitted to Journal of Geophysical Research) #12;2 1. Introduction Atmospheric pollution has1 Parameterization of urban sub-grid scale processes in global atmospheric chemistry models Josep such as meteorology. Effective emissions may be ?aged? emissions of primary pollutants or actual production

109

Overturning and wind driven circulation in a low-order ocean-atmosphere model  

E-Print Network [OSTI]

july 2002 Abstract A low-order ocean-atmosphere model is presented which combines coupling through heat exchange at the interface and wind stress forcing. The coupling terms are derived from the boundary conditions and the forcing terms of the constituents. Both the ocean and the atmosphere model are based

van Veen, Lennaert

110

Multiscale models of atmospheric mercury: bromine chemistry, air-sea exchange, and global transport  

E-Print Network [OSTI]

entrainment of RGM-rich air from the free troposphere (25­40%). Oxidation of Hg0 by Cl is minor (3Multiscale models of atmospheric mercury: bromine chemistry, air-sea exchange, and global transport Multiscale models of atmospheric mercury: bromine chemistry, air-sea exchange, and global transport Abstract

Holmes, Christopher D.

111

Laboratory measurements and modeling of trace atmospheric species  

E-Print Network [OSTI]

Trace species play a major role in many physical and chemical processes in the atmosphere. Improving our understanding of the impact of each species requires a combination of laboratory exper- imentation, field measurements, ...

Sheehy, Philip M. (Philip Michael)

2005-01-01T23:59:59.000Z

112

Soil moisture in complex terrain: quantifying effects on atmospheric boundary layer flow and providing improved surface boundary conditions for mesoscale models  

E-Print Network [OSTI]

74 ii Soil Moisture Sensors: Decagon ECH2O Capacitance133 A.10 Soil types corresponding to each75 Soil Moisture and Temperature Probe

Daniels, Megan Hanako

2010-01-01T23:59:59.000Z

113

Soil moisture in complex terrain: quantifying effects on atmospheric boundary layer flow and providing improved surface boundary conditions for mesoscale models  

E-Print Network [OSTI]

red indicates water towers generated by kinematic wavethe kinematic wave equation will begin to collect water onred indicates water towers generated by kinematic wave

Daniels, Megan Hanako

2010-01-01T23:59:59.000Z

114

Soil moisture in complex terrain: quantifying effects on atmospheric boundary layer flow and providing improved surface boundary conditions for mesoscale models  

E-Print Network [OSTI]

direction, (b) wind speed, (c) potential temperature, and (Airport of potential temperature, wind speed, winderrors (bias) for potential temperature, wind speed, wind

Daniels, Megan Hanako

2010-01-01T23:59:59.000Z

115

Temporal Changes in Wind as Objects for Evaluating Mesoscale Numerical Weather Prediction  

E-Print Network [OSTI]

a method of evaluating numerical weather prediction models by comparing the characteristics of temporal for biases in features forecast by the model. 1. Introduction Verification of numerical weather predictionTemporal Changes in Wind as Objects for Evaluating Mesoscale Numerical Weather Prediction DARAN L

Knievel, Jason Clark

116

Annular mode-like responses to external forcings in a simple atmospheric general circulation model  

E-Print Network [OSTI]

In this thesis, I investigate the response of a simple atmospheric general circulation model to applied forcings to learn whether the annular mode patterns are a preferred model response to the forcings. The thesis is ...

Ring, Michael J., 1979-

2008-01-01T23:59:59.000Z

117

Evaluation of Hydrometeor Occurrence Profiles in the Multiscale Modeling Framework Climate Model using Atmospheric Classification  

SciTech Connect (OSTI)

Vertical profiles of hydrometeor occurrence from the Multiscale Modeling Framework (MMF) climate model are compared with profiles observed by a vertically pointing millimeter wavelength cloud-radar (located in the U.S. Southern Great Plains) as a function of the largescale atmospheric state. The atmospheric state is determined by classifying (or clustering) the large-scale (synoptic) fields produced by the MMF and a numerical weather prediction model using a neural network approach. The comparison shows that for cold frontal and post-cold frontal conditions the MMF produces profiles of hydrometeor occurrence that compare favorably with radar observations, while for warm frontal conditions the model tends to produce hydrometeor fractions that are too large with too much cloud (non-precipitating hydrometeors) above 7 km and too much precipitating hydrometeor coverage below 7 km. We also find that the MMF has difficulty capturing the formation of low clouds and that for all atmospheric states that occur during June, July, and August, the MMF produces too much high and thin cloud, especially above 10 km.

Marchand, Roger T.; Beagley, Nathaniel; Ackerman, Thomas P.

2009-09-01T23:59:59.000Z

118

Mesoscale convective complex vs. non-mesoscale convective complex thunderstorms: a comparison of selected meteorological variables  

E-Print Network [OSTI]

MESOSCALE CONVECTIVE CCMPLLX VS. NON-MESOSCALE CONVECTIVE COMPLEX THUNDERSTORMS: A COMPARISON OF SELECTED METEOROLOGICAL VARIABLES A Thesis MICHAkL EUGENE JJOOFARD Submitted to the Graduate College of Texas AJkM University in partial... by MICHAEL EUGENE HOOFARD Approved as to style and content by: a ter . enry (Chairman of Committee) %~5 44 c5 c usan gur c (Member) ona . oc ing (Member) ames . cogg (Head of Department) August 1986 ABSTRACT Nesoscale Convective Complex vs. Non...

Hoofard, Michael Eugene

1986-01-01T23:59:59.000Z

119

Summary of the March 25--26, 1991 atmospheric model working meeting  

SciTech Connect (OSTI)

Atmospheric transport and diffusion calculations for the initial phase of the Hanford Environmental Dose Reconstruction (HEDR) Project were made using the MESOILT2 computer code (Ramsdell and Burk 1991). This code implemented a Lagrangian trajectory, puff dispersion model using components from other models designed primarily for regulatory applications. Uncertainty in the dispersion calculations was estimated following model calculations. The results of the atmospheric dispersion calculations were summarized in frequency distributions by location for use in preliminary dose calculations.

Ramsdell, J.V.

1992-07-01T23:59:59.000Z

120

Modelling of Stellar Atmospheres IAU Symposium, Vol. xxx, xxxx  

E-Print Network [OSTI]

Abstract. We discuss the dynamics in the outer atmospheres of AGB giants. 1. Motivation Hinkle et al. (1982 with an excitation temperature of about 800-1000 K and an almost zero velocity relative to the stellar systemic molecular envelope", should be common not only in Miras but in evolved red giants in general. 2. Project

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121

Lesson Summary Students will use models of Earth's atmosphere  

E-Print Network [OSTI]

to learn about the causes and effects of global warming, the better prepared we may be to deal of human actions. Global warming refers to the rise in temperatures at Earth's surface and lower atmosphere are contributing to global warming. The danger in this warming is that it could disrupt Earth's climate patterns

Mojzsis, Stephen J.

122

ATMOSPHERIC TURBULENCE MODELING AND IMPLICATIONS FOR WIND ENERGY  

E-Print Network [OSTI]

turbines off too early in high winds, or may risk severe damage to the rotors and blades by operating under Introduction Wind turbines sit at the very bottom of the at- mospheric boundary layer, where winds are highly turbulent, shear events are intermittent, and land- atmosphere interactions may be strong. Turbine hub

Chow, Fotini Katopodes

123

A Simple Atmospheric Model of the Local and Teleconnection Responses to Tropical Heating Anomalies  

E-Print Network [OSTI]

the local and remote stationary responses of the atmosphere to tropical heating anomalies is describedA Simple Atmospheric Model of the Local and Teleconnection Responses to Tropical Heating Anomalies and forced with a localized heating for illustration. In the tropics, the baroclinic responses are familiar

Wang, Chunzai

124

Atmospheric transport and dispersion modeling for the Hanford Environmental Dose Reconstruction Project  

SciTech Connect (OSTI)

Radiation doses that may have resulted from operations at the Hanford Site are being estimated in the Hanford Environmental Dose Reconstruction (HEDR) Project. One of the project subtasks, atmospheric transport, is responsible for estimating the transport, diffusion and deposition of radionuclides released to the atmosphere. This report discusses modeling transport and diffusion in the atmospheric pathway. It is divided into three major sections. The first section of the report presents the atmospheric modeling approach selected following discussion with the Technical Steering Panel that directs the HEDR Project. In addition, the section discusses the selection of the MESOI/MESORAD suite of atmospheric dispersion models that form the basis for initial calculations and future model development. The second section of the report describes alternative modeling approaches that were considered. Emphasis is placed on the family of plume and puff models that are based on Gaussian solution to the diffusion equations. The final portion of the section describes the performance of various models. The third section of the report discusses factors that bear on the selection of an atmospheric transport modeling approach for HEDR. These factors, which include the physical setting of the Hanford Site and the available meteorological data, serve as constraints on model selection. Five appendices are included in the report. 39 refs., 4 figs., 2 tabs.

Ramsdell, J.V.

1991-07-01T23:59:59.000Z

125

Impact of emissions, chemistry, and climate on atmospheric carbon monoxide : 100-year predictions from a global chemistry-climate model  

E-Print Network [OSTI]

The possible trends for atmospheric carbon monoxide in the next 100 yr have been illustrated using a coupled atmospheric chemistry and climate model driven by emissions predicted by a global economic development model. ...

Wang, Chien.; Prinn, Ronald G.

126

Predicting Coupled Ocean-Atmosphere Modes with a Climate Modeling Hierarchy -- Final Report  

SciTech Connect (OSTI)

The goal of the project was to determine midlatitude climate predictability associated with tropical-extratropical interactions on interannual-to-interdecadal time scales. Our strategy was to develop and test a hierarchy of climate models, bringing together large GCM-based climate models with simple fluid-dynamical coupled ocean-ice-atmosphere models, through the use of advanced probabilistic network (PN) models. PN models were used to develop a new diagnostic methodology for analyzing coupled ocean-atmosphere interactions in large climate simulations made with the NCAR Parallel Climate Model (PCM), and to make these tools user-friendly and available to other researchers. We focused on interactions between the tropics and extratropics through atmospheric teleconnections (the Hadley cell, Rossby waves and nonlinear circulation regimes) over both the North Atlantic and North Pacific, and the oceans thermohaline circulation (THC) in the Atlantic. We tested the hypothesis that variations in the strength of the THC alter sea surface temperatures in the tropical Atlantic, and that the latter influence the atmosphere in high latitudes through an atmospheric teleconnection, feeding back onto the THC. The PN model framework was used to mediate between the understanding gained with simplified primitive equations models and multi-century simulations made with the PCM. The project team is interdisciplinary and built on an existing synergy between atmospheric and ocean scientists at UCLA, computer scientists at UCI, and climate researchers at the IRI.

Michael Ghil, UCLA; Andrew W. Robertson, IRI, Columbia Univ.; Sergey Kravtsov, U. of Wisconsin, Milwaukee; Padhraic Smyth, UC Irvine

2006-08-04T23:59:59.000Z

127

Toward a Fully Lagrangian Atmospheric Modeling System JAHRUL M. ALAM AND JOHN C. LIN  

E-Print Network [OSTI]

weather prediction (NWP) models]. A better numerical treatment of the nonlinear advection process numerical model is, therefore, presented for calculating atmospheric flows. The model employs a Lagrangian). Such models require numerical simu- lation of advection-dominated flow problems. The re- alization

Lin, John Chun-Han

128

AMPS, a real-time mesoscale modeling system, has provided a decade of service for scientific and logistical needs and has helped advance polar numerical weather prediction  

E-Print Network [OSTI]

and logistical needs and has helped advance polar numerical weather prediction as well as understanding support for the USAP. The concern at the time was the numerical weather prediction (NWP) guidance-time implementation of the Weather Research and Forecasting model (WRF; Skamarock et al. 2008) to support the U

Howat, Ian M.

129

Mesoscale model cloud scheme assessment using satellite observations Jean-Pierre Chaboureau, Jean-Pierre Cammas, Patrick J. Mascart, and Jean-Pierre Pinty  

E-Print Network [OSTI]

, tests made with three different values of an ice to snow autoconversion threshold reveal a profound-scale cloudiness in the model. A similar test conducted on the ice water and the liquid water paths confirms and water vapor. Once cloud is formed, however, it is the role of the microphysical scheme to parameterize

Chaboureau, Jean-Pierre

130

E-Print Network 3.0 - atmosphere-wildland fire model Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Computer Technologies and Information Sciences 6 A wildland fire model with data assimilation Jan Mandel ,a,b Summary: is to build a real-time coupled atmospheric-wildland fire...

131

E-Print Network 3.0 - atmosphere box model Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Ecology 6 Investigating Large-scale Contemporary CO2 Sources and Sinks Using Inverse Transport Modelling Applied to CO2, CH4 and CO Summary: in atmospheric CO2 concentration. 3....

132

Accelerated Iterative Method for Solving Steady Solutions of Linearized Atmospheric Models  

E-Print Network [OSTI]

Accelerated Iterative Method for Solving Steady Solutions of Linearized Atmospheric Models Masahiro approach, referred to as the accelerated iterative method (AIM), is developed for solving steady state, respectively. For ensuring the accelerated asymptotic convergence of iterative procedure

Watanabe, Masahiro

133

The Surface-Pressure Signature of Atmospheric Tides in Modern Climate Models  

E-Print Network [OSTI]

Although atmospheric tides driven by solar heating are readily detectable at the earths surface as variations in air pressure, their simulations in current coupled global climate models have not been fully examined. This ...

Covey, Curt

134

E-Print Network 3.0 - atmospheric pollutant modeling Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Sample search results for: atmospheric pollutant modeling Page: << < 1 2 3 4 5 > >> 1 Air Pollution Physics and Chemistry EAS 6790 Monday, Wednesday, Friday 2:05 to 2:55...

135

Visualizing Storms from NCAR's Atmosphere Model at NERSC  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLasDelivered energy consumption by sectorlongUpdatesValley winsVideoVisitorTransportAtmosphere

136

A PHYSICALLY-BASED SCHEME FOR THE URBAN ENERGY BUDGET IN ATMOSPHERIC MODELS  

E-Print Network [OSTI]

A PHYSICALLY-BASED SCHEME FOR THE URBAN ENERGY BUDGET IN ATMOSPHERIC MODELS VALRY MASSON Centre published data. Firstly, it is shown that the evolution of the model-predicted fluxes during a night. These two validations show that the radiative energy input to the urban surface model is realistic

Ribes, Aurlien

137

Initial atmospheric-dispersion modeling in support of the multiple-site incineration study  

SciTech Connect (OSTI)

Several modeling series which estimate population exposure to stack emissions from incineration of hazardous organic materials at 22 commercial incinerator sites are presented. These modeling series can be divided into three groups. One group estimates long- and short-term atmospheric concentrations and population exposures for each of 22 sites. These modeling predictions can be used to assess chronic and acute exposure. The second group consists of sensitivity analyses which show the effect of changes in stack parameters on the number of people exposed to specified concentration levels. The third group compares concentration estimates of two atmospheric dispersion computer codes. Results of each modeling series are contained in the appendices of this report.

Holton, G.A.; Little, C.A.; O& #x27; Donnell, F.R.; Etnier, E.L.; Travis, C.C.

1982-04-01T23:59:59.000Z

138

Estimation of errors in the inverse modeling of accidental release of atmospheric pollutant: Application to the reconstruction  

E-Print Network [OSTI]

Estimation of errors in the inverse modeling of accidental release of atmospheric pollutant difficulty when inverting the source term of an atmospheric tracer dispersion problem is the estimation of the prior errors: those of the atmospheric transport model, those ascribed to the representativity

Paris-Sud XI, Université de

139

Sparse optimization for inverse problems in atmospheric modelling  

E-Print Network [OSTI]

Apr 13, 2015 ... In S.-E. Gryning and F. Schiermeier, editors, Air Pollution Modeling and Its Application. XI, volume 21 of NATO Challenges of Modern Society,...

2015-04-13T23:59:59.000Z

140

Scaling turbulent atmospheric stratification: a turbulence/wave wind model  

E-Print Network [OSTI]

, it displays no wave-like phenomenol- ogy. We show how to extend the FIF model to account for more realistic

Lovejoy, Shaun

Note: This page contains sample records for the topic "atmospheric mesoscale model" from the National Library of EnergyBeta (NLEBeta).
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141

Improved Meteorological Input for Atmospheric Release Decision support Systems and an Integrated LES Modeling System for Atmospheric Dispersion of Toxic Agents: Homeland Security Applications  

SciTech Connect (OSTI)

When hazardous material is accidently or intentionally released into the atmosphere, emergency response organizations look to decision support systems (DSSs) to translate contaminant information provided by atmospheric models into effective decisions to protect the public and emergency responders and to mitigate subsequent consequences. The Department of Homeland Security (DHS)-led Interagency Modeling and Atmospheric Assessment Center (IMAAC) is one of the primary DSSs utilized by emergency management organizations. IMAAC is responsible for providing 'a single piont for the coordination and dissemination of Federal dispersion modeling and hazard prediction products that represent the Federal position' during actual or potential incidents under the National Response Plan. The Department of Energy's (DOE) National Atmospheric Release Advisory Center (NARAC), locatec at the Lawrence Livermore National Laboratory (LLNL), serves as the primary operations center of the IMAAC. A key component of atmospheric release decision support systems is meteorological information - models and data of winds, turbulence, and other atmospheric boundary-layer parameters. The accuracy of contaminant predictions is strongly dependent on the quality of this information. Therefore, the effectiveness of DSSs can be enhanced by improving the meteorological options available to drive atmospheric transport and fate models. The overall goal of this project was to develop and evaluate new meteorological modeling capabilities for DSSs based on the use of NASA Earth-science data sets in order to enhance the atmospheric-hazard information provided to emergency managers and responders. The final report describes the LLNL contributions to this multi-institutional effort. LLNL developed an approach to utilize NCAR meteorological predictions using NASA MODIS data for the New York City (NYC) region and demonstrated the potential impact of the use of different data sources and data parameterizations on IMAAC/NARAC fate and transport predictions. A case study involving coastal sea breeze circulation patterns in the NYC region was used to investigate the sensitivity of atmospheric dispersion results on the source of three-dimensional wind field data.

Arnold, E; Simpson, M; Larsen, S; Gash, J; Aluzzi, F; Lundquist, J; Sugiyama, G

2010-04-26T23:59:59.000Z

142

Time Step Sensitivity of Nonlinear Atmospheric Models: Numerical Convergence, Truncation Error Growth, and Ensemble Design  

E-Print Network [OSTI]

1973; Oran and Boris 1987; Murray 1989; Gershenfeld 1999). Weather and climate prediction models, which to the initial conditions, which is a major source of uncertainty in Numerical Weather Prediction (NWP; eTime Step Sensitivity of Nonlinear Atmospheric Models: Numerical Convergence, Truncation Error

Judd, Kevin

143

Sensitivity of an Ocean-Atmosphere Coupled Model to the Coupling Method : Study of Tropical Cyclone  

E-Print Network [OSTI]

Sensitivity of an Ocean-Atmosphere Coupled Model to the Coupling Method : Study of Tropical Cyclone) in a realistic configuration aiming at simulating the genesis and propagation of tropical cyclone Erica and Oceanic Coupled Models (AOCMs) which account for important air-sea feedbacks. Separate integrations

Recanati, Catherine

144

MEASUREMENT AND MODELLING OF AMMONIA EMISSIONS AT WASTE TREATMENT LAGOON-ATMOSPHERIC INTERFACE  

E-Print Network [OSTI]

MEASUREMENT AND MODELLING OF AMMONIA EMISSIONS AT WASTE TREATMENT LAGOON-ATMOSPHERIC INTERFACE animals ( 32 Tg N -1yr-1). Waste storage and treatment lagoons are used to treat the excreta of hogs waste storage and treatment lagoon in NC using a dynamic emission flux chamber. Results of model

Aneja, Viney P.

145

The impact of methane thermodynamics on seasonal convection and circulation in a model Titan atmosphere  

E-Print Network [OSTI]

The impact of methane thermodynamics on seasonal convection and circulation in a model Titan mechanisms controlling the distribution of methane convection and large-scale circulation in a simplified, axisymmetric model atmosphere of Titan forced by gray radiation and moist (methane) con- vection. The large

Caballero, Rodrigo

146

MODELING ATMOSPHERIC RELEASES OF TRITIUM FROM NUCLEAR INSTALLATIONS  

SciTech Connect (OSTI)

Tritium source term analysis and the subsequent dispersion and consequence analyses supporting the safety documentation of Department of Energy nuclear facilities are especially sensitive to the applied software analysis methodology, input data and user assumptions. Three sequential areas in tritium accident analysis are examined in this study to illustrate where the analyst should exercise caution. Included are: (1) the development of a tritium oxide source term; (2) use of a full tritium dispersion model based on site-specific information to determine an appropriate deposition scaling factor for use in more simplified, broader modeling, and (3) derivation of a special tritium compound (STC) dose conversion factor for consequence analysis, consistent with the nature of the originating source material. It is recommended that unless supporting, defensible evidence is available to the contrary, the tritium release analyses should assume tritium oxide as the species released (or chemically transformed under accident's environment). Important exceptions include STC situations and laboratory-scale releases of hydrogen gas. In the modeling of the environmental transport, a full phenomenology model suggests that a deposition velocity of 0.5 cm/s is an appropriate value for environmental features of the Savannah River Site. This value is bounding for certain situations but non-conservative compared to the full model in others. Care should be exercised in choosing other factors such as the exposure time and the resuspension factor.

Okula, K

2007-01-17T23:59:59.000Z

147

A Flexible Atmospheric Modeling Framework for the CESM  

SciTech Connect (OSTI)

We have created two global dynamical cores based on the unified system of equations and Z-grid staggering on an icosahedral grid, which are collectively called UZIM (Unified Z-grid Icosahedral Model). The z-coordinate version (UZIM-height) can be run in hydrostatic and nonhydrostatic modes. The sigma-coordinate version (UZIM-sigma) runs in only hydrostatic mode. The super-parameterization has been included as a physics option in both models. The UZIM versions with the super-parameterization are called SUZI. With SUZI-height, we have completed aquaplanet runs. With SUZI-sigma, we are making aquaplanet runs and realistic climate simulations. SUZI-sigma includes realistic topography and a SiB3 model to parameterize the land-surface processes.

Randall, David [Colorado State University; Heikes, Ross [Colorado State University; Konor, Celal [Colorado State University

2014-11-12T23:59:59.000Z

148

Air pollution forecasting by coupled atmosphere-fire model WRF and SFIRE with WRF-Chem  

E-Print Network [OSTI]

Atmospheric pollution regulations have emerged as a dominant obstacle to prescribed burns. Thus, forecasting the pollution caused by wildland fires has acquired high importance. WRF and SFIRE model wildland fire spread in a two-way interaction with the atmosphere. The surface heat flux from the fire causes strong updrafts, which in turn change the winds and affect the fire spread. Fire emissions, estimated from the burning organic matter, are inserted in every time step into WRF-Chem tracers at the lowest atmospheric layer. The buoyancy caused by the fire then naturally simulates plume dynamics, and the chemical transport in WRF-Chem provides a forecast of the pollution spread. We discuss the choice of wood burning models and compatible chemical transport models in WRF-Chem, and demonstrate the results on case studies.

Kochanski, Adam K; Mandel, Jan; Clements, Craig B

2013-01-01T23:59:59.000Z

149

A grid of synthetic ionizing spectra for very hot compact stars from NLTE model atmospheres  

E-Print Network [OSTI]

The precise analysis of properties of planetary nebulae is strongly dependent on good models for the stellar ionizing spectrum. Observations in the UV - X-ray wavelength range as well as NLTE model atmosphere calculations of spectra of their exciting stars have shown that neither blackbody fluxes nor "standard" NLTE atmosphere models which are composed out of hydrogen and helium only are good approximations. Strong differences between synthetic spectra from these compared to observed spectra at energies higher than 54 eV (He II ground state) can be ascribed to the neglect of metal-line blanketing. Realistic modeling of the emergent fluxes of hot stars in the UV - X-ray wavelength range requires metal-line blanketed NLTE model atmospheres which include all elements from hydrogen up to the iron-group. For this purpose, we present a grid (solar and halo abundance ratios) of metal-line blanketed NLTE model atmosphere fluxes which covers the parameter range of central stars of planetary nebulae.

Thomas Rauch

2003-03-20T23:59:59.000Z

150

O3-NOx-VOC sensitivity and NOx-VOC indicators in Paris: Results from models and Atmospheric Pollution Over  

E-Print Network [OSTI]

from the Atmospheric Pollution Over the Paris Area campaign near Paris, with special attention Composition and Structure: Pollution--urban and regional (0305); 0365 Atmospheric Composition and Structure-VOC indicators in Paris: Results from models and Atmospheric Pollution Over the Paris Area (ESQUIF) measurements

Menut, Laurent

151

Inferring catchment precipitation by doing hydrology backward: A test in 24 small and mesoscale catchments in Luxembourg  

E-Print Network [OSTI]

Inferring catchment precipitation by doing hydrology backward: A test in 24 small and mesoscale September 2012; published 10 October 2012. [1] The complexity of hydrological systems and the necessary simplification of models describing these systems remain major challenges in hydrological modeling. Kirchner

Kirchner, James W.

152

Causes and Implications of Persistent Atmospheric Carbon Dioxide Biases in Earth System Models  

SciTech Connect (OSTI)

The strength of feedbacks between a changing climate and future CO2 concentrations are uncertain and difficult to predict using Earth System Models (ESMs). We analyzed emission-driven simulations--in which atmospheric CO2 levels were computed prognostically--for historical (1850-2005) and future periods (RCP 8.5 for 2006-2100) produced by 15 ESMs for the Fifth Phase of the Coupled Model Intercomparison Project (CMIP5). Comparison of ESM prognostic atmospheric CO2 over the historical period with observations indicated that ESMs, on average, had a small positive bias in predictions of contemporary atmospheric CO2. Weak ocean carbon uptake in many ESMs contributed to this bias, based on comparisons with observations of ocean and atmospheric anthropogenic carbon inventories. We found a significant linear relationship between contemporary atmospheric CO2 biases and future CO2 levels for the multi-model ensemble. We used this relationship to create a contemporary CO2 tuned model (CCTM) estimate of the atmospheric CO2 trajectory for the 21st century. The CCTM yielded CO2 estimates of 600 {plus minus} 14 ppm at 2060 and 947 {plus minus} 35 ppm at 2100, which were 21 ppm and 32 ppm below the multi-model mean during these two time periods. Using this emergent constraint approach, the likely ranges of future atmospheric CO2, CO2-induced radiative forcing, and CO2-induced temperature increases for the RCP 8.5 scenario were considerably narrowed compared to estimates from the full ESM ensemble. Our analysis provided evidence that much of the model-to-model variation in projected CO2 during the 21st century was tied to biases that existed during the observational era, and that model differences in the representation of concentration-carbon feedbacks and other slowly changing carbon cycle processes appear to be the primary driver of this variability. By improving models to more closely match the long-term time series of CO2 from Mauna Loa, our analysis suggests uncertainties in future climate projections can be reduced.

Hoffman, Forrest M [ORNL] [ORNL; Randerson, James T. [University of California, Irvine] [University of California, Irvine; Arora, Vivek K. [Canadian Centre for Climate Modelling and Analysis, Meteorological Service of Canada] [Canadian Centre for Climate Modelling and Analysis, Meteorological Service of Canada; Bao, Qing [State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics] [State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics; Cadule, Patricia [Institut Pierre Simon Laplace, Laboratoire des Sciences du Climat et de l'Environment] [Institut Pierre Simon Laplace, Laboratoire des Sciences du Climat et de l'Environment; Ji, Duoying [State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing] [State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing; Jones, Chris D. [Hadley Centre, U.K. Met Office] [Hadley Centre, U.K. Met Office; Kawamiya, Michio [Japan Agency for Marine-Earth Science and Technology (JAMSTEC)] [Japan Agency for Marine-Earth Science and Technology (JAMSTEC); Khatiwala, Samar [Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY] [Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY; Lindsay, Keith [National Center for Atmospheric Research (NCAR)] [National Center for Atmospheric Research (NCAR); Obata, Atsushi [Meteorological Research Institute, Japan] [Meteorological Research Institute, Japan; Shevliakova, Elena [Princeton University] [Princeton University; Six, Katharina D. [Max Planck Institute for Meteorology, Hamburg, Germany] [Max Planck Institute for Meteorology, Hamburg, Germany; Tjiputra, Jerry F. [Uni Climate, Uni Research] [Uni Climate, Uni Research; Volodin, Evgeny M. [Institute of Numerical Mathematics, Russian Academy of Science, Moscow] [Institute of Numerical Mathematics, Russian Academy of Science, Moscow; Wu, Tongwen [China Meteorological Administration (CMA), Beijing] [China Meteorological Administration (CMA), Beijing

2014-01-01T23:59:59.000Z

153

Long-Range Atmospheric Transport of Polycyclic Aromatic Hydrocarbons: A Global 3-D Model Analysis Including Evaluation of Arctic Sources  

E-Print Network [OSTI]

We use the global 3-D chemical transport model GEOS-Chem to simulate long-range atmospheric transport of polycyclic aromatic hydrocarbons (PAHs). To evaluate the models ability to simulate PAHs with different volatilities, ...

Friedman, Carey

154

Found: The missing blue opacity in atmosphere models of cool hydrogen white dwarfs  

E-Print Network [OSTI]

We investigate the importance of the far red wing of the Lyman $ \\alpha$ line of hydrogen in the atmospheres of cool white dwarfs of pure hydrogen composition. We find that this absorption process dominates all important sources of opacity in the blue part of the optical spectrum of these stars. Our successful fits to the spectra of cool DA/DC white dwarfs indicate that the far red wing of the $\\rm Ly \\alpha$ line is the source of opacity that had been missing in the models. The observed sequence of cool white dwarfs in color-color diagrams is very well reproduced by our new pure hydrogen atmosphere models, suggesting that the atmospheric composition of the coolest DC white dwarfs must be revisited.

P. M. Kowalski; D. Saumon

2006-09-26T23:59:59.000Z

155

The dynamics of a low-order coupled ocean-atmosphere model  

E-Print Network [OSTI]

A system of five ordinary differential equations is studied which combines the Lorenz-84 model for the atmosphere and a box model for the ocean. The behaviour of this system is studied as a function of the coupling parameters. For most parameter values, the dynamics of the atmosphere model is dominant. For a range of parameter values, competing attractors exist. The Kaplan-Yorke dimension and the correlation dimension of the chaotic attractor are numerically calculated and compared to the values found in the uncoupled Lorenz model. In the transition from periodic behaviour to chaos intermittency is observed. The intermittent behaviour occurs near a Neimark-Sacker bifurcation at which a periodic solution loses its stability. The length of the periodic intervals is governed by the time scale of the ocean component. Thus, in this regime the ocean model has a considerable influence on the dynamics of the coupled system.

L. van Veen; F. Verhulst; T. Opsteegh

1998-12-16T23:59:59.000Z

156

Modeling Activities in the Department of Energys Atmospheric Sciences Program  

SciTech Connect (OSTI)

The Department of Energy's Atmospheric Science Program (ASP) conducts research pertinent to radiative forcing of climate change by atmospheric aerosols. The program consists of approximately 40 highly interactive peer-reviewed research projects that examine aerosol properties and processes and the evolution of aerosols in the atmosphere. Principal components of the program are instrument development, laboratory experiments, field studies, theoretical investigations, and modeling. The objectives of the Program are to 1) improve the understanding of aerosol processes associated with light scattering and absorption properties and interactions with clouds that affect Earth's radiative balance and to 2) develop model-based representations of these processes that enable the effects of aerosols on Earth's climate system to be properly represented in global-scale numerical climate models. Although only a few of the research projects within ASP are explicitly identified as primarily modeling activities, modeling actually comprises a substantial component of a large fraction of ASP research projects. This document describes the modeling activities within the Program as a whole, the objectives and intended outcomes of these activities, and the linkages among the several modeling components and with global-scale modeling activities conducted under the support of the Department of Energy's Climate Sciences Program and other aerosol and climate research programs.

Fast, Jerome D.; Ghan, Steven J.; Schwartz, Stephen E.

2009-03-01T23:59:59.000Z

157

Three Dimensional Adaptive Mesh Refinement on a Spherical Shell for Atmospheric Models with Lagrangian Coordinates  

E-Print Network [OSTI]

Three Dimensional Adaptive Mesh Refinement on a Spherical Shell for Atmospheric Models blocks and splits a block as refinements occur. The current functionality provides automatic generation the use of a longer time step. We have developed an Adaptive Mesh Refinement (AMR) dynamical core

Jablonowski, Christiane

158

Laboratory modelling of atmospheric dynamical processes J. Sommeria and H. Didelle  

E-Print Network [OSTI]

of cars or airplanes is commonly tested in wind tunnels. The wake of ships and the impact of waves in the Giant planet atmosphere. Finally examples of topographic wakes in a stratified fluid and gravity of field measurements. For instance validation of a model by observations in the present climatic

Paris-Sud XI, Université de

159

Measurements and modelling of atmospheric pollution over the Paris area: an overview of the ESQUIF Project  

E-Print Network [OSTI]

dedicated to the study of the processes leading to air pollution events over the Paris area. The project, pollution levels in the Paris area due to concentrated activity have become a major health issue. CurrentMeasurements and modelling of atmospheric pollution over the Paris area: an overview of the ESQUIF

Paris-Sud XI, Université de

160

Idealized test cases for the dynamical cores of Atmospheric General Circulation Models  

E-Print Network [OSTI]

Idealized test cases for the dynamical cores of Atmospheric General Circulation Models: A proposal) Ram Nair (NCAR) Mark Taylor (Sandia National Laboratory) May/29/2008 1 Idealized test cases for 3D dynamical cores This document describes the idealized dynamical core test cases that are proposed

Jablonowski, Christiane

Note: This page contains sample records for the topic "atmospheric mesoscale model" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Sensitivity of Ocean-Atmosphere Coupled Models to the Coupling Method : Example of Tropical Cyclone  

E-Print Network [OSTI]

Sensitivity of Ocean-Atmosphere Coupled Models to the Coupling Method : Example of Tropical Cyclone and propagation of tropical cyclone Erica. Sensitiv- ity tests to the coupling method are carried out-sea feedbacks. Separate integrations of the Corresponding author. Phone: +33 (0)4 76 51 48 60 Fax: +33 (0)4 76

162

Aerosol Effects on Cirrus through Ice Nucleation in the Community Atmosphere Model CAM5 with a Statistical Cirrus Scheme  

SciTech Connect (OSTI)

A statistical cirrus cloud scheme that tracks ice saturation ratio in the clear-sky and cloudy portion of a grid box separately has been implemented into NCAR CAM5 to provide a consistent treatment of ice nucleation and cloud formation. Simulated ice supersaturation and ice crystal number concentrations strongly depend on the number concentrations of heterogeneous ice nuclei (IN), subgrid temperature formulas and the number concentration of sulfate particles participating in homogeneous freezing, while simulated ice water content is insensitive to these perturbations. 1% to 10% dust particles serving as heterogeneous IN is 20 found to produce ice supersaturaiton in better agreement with observations. Introducing a subgrid temperature perturbation based on long-term aircraft observations of meso-scale motion produces a better hemispheric contrast in ice supersaturation compared to observations. Heterogeneous IN from dust particles significantly alter the net radiative fluxes at the top of atmosphere (TOA) (-0.24 to -1.59 W m-2) with a significant clear-sky longwave component (0.01 to -0.55 W m-2). Different cirrus treatments significantly perturb the net TOA anthropogenic aerosol forcing from -1.21 W m-2 to -1.54 W m-2, with a standard deviation of 0.10 W m-2. Aerosol effects on cirrus clouds exert an even larger impact on the atmospheric component of the radiative fluxes (two or three times the changes in the TOA radiative fluxes) and therefore on the hydrology cycle through the fast atmosphere response. This points to the urgent need to quantify aerosol effects on cirrus clouds through ice nucleation and how these further affect the hydrological cycle.

Wang, Minghuai; Liu, Xiaohong; Zhang, Kai; Comstock, Jennifer M.

2014-09-01T23:59:59.000Z

163

Tests of an ensemble Kalman filter for mesoscale and regional-scale data assimilation  

E-Print Network [OSTI]

technique with real observations (Houtekamer et al. 2005; Whitaker et al. 2006). However, the performance of the EnKF implemented in mesoscale models has not been compared directly to that of variational method. ____________ This dissertation follows... while perturbing the observation. However, the computation cost is very large when applying this method to high-degree- of-freedom systems. Whitaker and Hamill (2002) introduced the ensemble square-root filter (EnSRF) as a better way to deal...

Meng, Zhiyong

2007-09-17T23:59:59.000Z

164

Junhong Wei and Fuqing Zhang, Pennsylvania State University Mesoscale Gravity Waves in Moist Baroclinic Jet-Front Systems  

E-Print Network [OSTI]

with small amount of moisture, dry dynamic gravity wave modes continue to dominate. However, convective-permitting simulations with the Weather Research and Forecast (WRF) model are performed to study mesoscale gravity waves/negative), and 7-km dynamic tropopause (turquoise lines). Wave Identification Figure 3. Comparison of WP5 at 132 h

Thompson, Anne

165

Description and validation of ERAD: An atmospheric dispersion model for high explosive detonations  

SciTech Connect (OSTI)

The Explosive Release Atmospheric Dispersion (ERAD) model is a three-dimensional numerical simulation of turbulent atmospheric transport and diffusion. An integral plume rise technique is used to provide a description of the physical and thermodynamic properties of the cloud of warm gases formed when the explosive detonates. Particle dispersion is treated as a stochastic process which is simulated using a discrete time Lagrangian Monte Carlo method. The stochastic process approach permits a more fundamental treatment of buoyancy effects, calm winds and spatial variations in meteorological conditions. Computational requirements of the three-dimensional simulation are substantially reduced by using a conceptualization in which each Monte Carlo particle represents a small puff that spreads according to a Gaussian law in the horizontal directions. ERAD was evaluated against dosage and deposition measurements obtained during Operation Roller Coaster. The predicted contour areas average within about 50% of the observations. The validation results confirm the model`s representation of the physical processes.

Boughton, B.A.; DeLaurentis, J.M.

1992-10-01T23:59:59.000Z

166

Mesoscale Quantization and Self-Organized Stability  

E-Print Network [OSTI]

In the world of technology, one of the most important forms of friction is that of rolling friction. Yet it is one of the least studied of all the known forms of energy dissipation. In the present experiments we investigate the oscillatory free-decay of a rigid cube, whose side-length is less than the diameter of the rigid cylinder on which it rests. The resulting free-decay is one of harmonic motion with damping. The non-dissipative character of the oscillation yields to a linear differential equation; however, the damping is found to involve more than a deterministic nonlinearity. Dominated by rolling friction, the damping is sensitive to the material properties of the contact surfaces. For `clean' surfaces of glass on glass, the decay shows features of mesoscale quantization and self-organized stability.

Randall D. Peters

2005-06-16T23:59:59.000Z

167

MODELLING THE OVERLAND TRANSPORT OF LEAD DEPOSITED FROM THE ATMOSPHERE IN THE ELBE CATCHMENT OVER FOUR  

E-Print Network [OSTI]

unknown. Despite decreasing atmospheric pollution, soil and freshwater systems still indicate high lead on minimizing atmospheric emissions, but also on minimizing soil erosion. Keywords: atmospheric pollution, direct atmospheric deposition, direct runoff, Elbe catchment, erosion, soil pollution, lead, long

Costa-Cabral, Mariza

168

Evolution of moisture convergence in a mesoscale convective complex  

E-Print Network [OSTI]

Committee: Dr. Keuneth C. Brundidge Two separate Mesoscale Convective Complexes (MCCs) were investigated to determine if a characteristic surface moisture convergence (MC) signature existed on the mesoscale during their lifecycle. The first storm (Case 1... convergence, a bandpass filtering technique was utilized. It was found that MC could identify the general area of initial thunderstorm activity 2 h prior to its development for both cases. During the initial development stage of Case 1, advection...

Bercherer, John Phillip

1990-01-01T23:59:59.000Z

169

Single-Column Modeling, GCM Parameterizations and Atmospheric Radiation Measurement Data  

SciTech Connect (OSTI)

Our overall goal is identical to that of the Atmospheric Radiation Measurement (ARM) Program: the development of new and improved parameterizations of cloud-radiation effects and related processes, using ARM data at all three ARM sites, and the implementation and testing of these parameterizations in global and regional models. To test recently developed prognostic parameterizations based on detailed cloud microphysics, we have first compared single-column model (SCM) output with ARM observations at the Southern Great Plains (SGP), North Slope of Alaska (NSA) and Topical Western Pacific (TWP) sites. We focus on the predicted cloud amounts and on a suite of radiative quantities strongly dependent on clouds, such as downwelling surface shortwave radiation. Our results demonstrate the superiority of parameterizations based on comprehensive treatments of cloud microphysics and cloud-radiative interactions. At the SGP and NSA sites, the SCM results simulate the ARM measurements well and are demonstrably more realistic than typical parameterizations found in conventional operational forecasting models. At the TWP site, the model performance depends strongly on details of the scheme, and the results of our diagnostic tests suggest ways to develop improved parameterizations better suited to simulating cloud-radiation interactions in the tropics generally. These advances have made it possible to take the next step and build on this progress, by incorporating our parameterization schemes in state-of-the-art 3D atmospheric models, and diagnosing and evaluating the results using independent data. Because the improved cloud-radiation results have been obtained largely via implementing detailed and physically comprehensive cloud microphysics, we anticipate that improved predictions of hydrologic cycle components, and hence of precipitation, may also be achievable. We are currently testing the performance of our ARM-based parameterizations in state-of-the--art global and regional models. One fruitful strategy for evaluating advances in parameterizations has turned out to be using short-range numerical weather prediction as a test-bed within which to implement and improve parameterizations for modeling and predicting climate variability. The global models we have used to date are the CAM atmospheric component of the National Center for Atmospheric Research (NCAR) CCSM climate model as well as the National Centers for Environmental Prediction (NCEP) numerical weather prediction model, thus allowing testing in both climate simulation and numerical weather prediction modes. We present detailed results of these tests, demonstrating the sensitivity of model performance to changes in parameterizations.

Somerville, R.C.J.; Iacobellis, S.F.

2005-03-18T23:59:59.000Z

170

Monitoring and ANN modeling of coal stockpile behavior under different atmospheric conditions  

SciTech Connect (OSTI)

In this study, an industrial-sized stockpile of 5 m width, 4 m height, and 10 m length was built in a coal stock area to investigate coal stockpile behavior under different atmospheric conditions. The effective parameters on the coal stockpile that were time, weather temperature, atmospheric pressure, air humidity, velocity, and direction of wind values were automatically measured by means of a computer-aided measurement system to obtain Artificial Neural Network (ANN) input data. The coal stockpiles, which should be continuously observed, are capable of spontaneous combustion and then causing serious economical losses due to the mentioned parameters. Afterwards, these measurement values were used for training and testing of the ANN model. Comparison of the experimental and ANN results, accuracy rates of training, and testing were found as 98.6% and 98.7%, respectively. It is shown that possible coal stockpile behavior with this ANN model is powerfully estimated.

Ozdeniz, A.H.; Ozbay, Y.; Yilmaz, N.; Sensogut, C. [Selcuk University, Konya (Turkey). Engineering & Architecture Faculty

2008-07-01T23:59:59.000Z

171

Atmospheric transmission model for a solar beam propagating between a heliostat and a receiver  

SciTech Connect (OSTI)

Formulae are presented that provide estimates of the transmittance for a solar beam propagating between a heliostat and a central receiver. These formulae are wavelength independent, functional fits to the tabulated data of Vittitoe and Biggs, which in turn are from numerical integrations of spectral transmittance data calculated with the aid of the computer code LOWTRAN 3. The formulae allow for interpolation and extrapolation, and they have a form characteristic of atmospheric transmission models. The transmittance model contains five explicit physical variables (the site elevation H, the atmospheric water vapor density rho, the scattering coefficient ..beta.., the tower height h, and the slant range R) and three implicit variables (the season of the year, the climatic region, and the site elevation H) because rho and ..beta.. are dependent on these three variables.

Pitman, C.L.; Vant-Hull, L.L.

1982-01-01T23:59:59.000Z

172

What causes the large extensions of red-supergiant atmospheres? Comparisons of interferometric observations with 1-D hydrostatic, 3-D convection, and 1-D pulsating model atmospheres  

E-Print Network [OSTI]

We present the atmospheric structure and the fundamental parameters of three red supergiants, increasing the sample of RSGs observed by near-infrared spectro-interferometry. Additionally, we test possible mechanisms that may explain the large observed atmospheric extensions of RSGs. We carried out spectro-interferometric observations of 3 RSGs in the near-infrared K-band with the VLTI/AMBER instrument at medium spectral resolution. To comprehend the extended atmospheres, we compared our observational results to predictions by available hydrostatic PHOENIX, available 3-D convection, and new 1-D self-excited pulsation models of RSGs. Our near-infrared flux spectra are well reproduced by the PHOENIX model atmospheres. The continuum visibility values are consistent with a limb-darkened disk as predicted by the PHOENIX models, allowing us to determine the angular diameter and the fundamental parameters of our sources. Nonetheless, in the case of V602 Car and HD 95686, the PHOENIX model visibilities do not predict ...

Arroyo-Torres, B; Chiavassa, A; Scholz, M; Freytag, B; Marcaide, J M; Hauschildt, P H; Wood, P R; Abellan, F J

2015-01-01T23:59:59.000Z

173

A Model of Intra-seasonal Oscillations in the Earth atmosphere  

E-Print Network [OSTI]

We suggest a way of rationalizing an intra-seasonal oscillations (IOs) of the Earth atmospheric flow as four meteorological relevant triads of interacting planetary waves, isolated from the system of all the rest planetary waves. Our model is independent of the topography (mountains, etc.) and gives a natural explanation of IOs both in the North and South Hemispheres. Spherical planetary waves are an example of a wave mesoscopic system obeying discrete resonances that also appears in other areas of physics.

Elena Kartashova; Victor S. L'vov

2007-04-04T23:59:59.000Z

174

Short ensembles: An Efficient Method for Discerning Climate-relevant Sensitivities in Atmospheric General Circulation Models  

SciTech Connect (OSTI)

This paper explores the feasibility of an experimentation strategy for investigating sensitivities in fast components of atmospheric general circulation models. The basic idea is to replace the traditional serial-in-time long-term climate integrations by representative ensembles of shorter simulations. The key advantage of the proposed method lies in its efficiency: since fewer days of simulation are needed, the computational cost is less, and because individual realizations are independent and can be integrated simultaneously, the new dimension of parallelism can dramatically reduce the turnaround time in benchmark tests, sensitivities studies, and model tuning exercises. The strategy is not appropriate for exploring sensitivity of all model features, but it is very effective in many situations. Two examples are presented using the Community Atmosphere Model version 5. The first example demonstrates that the method is capable of characterizing the model cloud and precipitation sensitivity to time step length. A nudging technique is also applied to an additional set of simulations to help understand the contribution of physics-dynamics interaction to the detected time step sensitivity. In the second example, multiple empirical parameters related to cloud microphysics and aerosol lifecycle are perturbed simultaneously in order to explore which parameters have the largest impact on the simulated global mean top-of-atmosphere radiation balance. Results show that in both examples, short ensembles are able to correctly reproduce the main signals of model sensitivities revealed by traditional long-term climate simulations for fast processes in the climate system. The efficiency of the ensemble method makes it particularly useful for the development of high-resolution, costly and complex climate models.

Wan, Hui; Rasch, Philip J.; Zhang, Kai; Qian, Yun; Yan, Huiping; Zhao, Chun

2014-09-08T23:59:59.000Z

175

A DETAILED MODEL ATMOSPHERE ANALYSIS OF COOL WHITE DWARFS IN THE SLOAN DIGITAL SKY SURVEY  

SciTech Connect (OSTI)

We present optical spectroscopy and near-infrared photometry of 126 cool white dwarfs (WDs) in the Sloan Digital Sky Survey (SDSS). Our sample includes high proper motion targets selected using the SDSS and USNO-B astrometry and a dozen previously known ultracool WD candidates. Our optical spectroscopic observations demonstrate that a clean selection of large samples of cool WDs in the SDSS (and the SkyMapper, Pan-STARRS, and the Large Synoptic Survey Telescope data sets) is possible using a reduced proper motion diagram and a tangential velocity cut-off (depending on the proper motion accuracy) of 30 km s{sup -1}. Our near-infrared observations reveal eight new stars with significant absorption. We use the optical and near-infrared photometry to perform a detailed model atmosphere analysis. More than 80% of the stars in our sample are consistent with either pure hydrogen or pure helium atmospheres. However, the eight stars with significant infrared absorption and the majority of the previously known ultracool WD candidates are best explained with mixed hydrogen and helium atmosphere models. The age distribution of our sample is consistent with a Galactic disk age of 8 Gyr. A few ultracool WDs may be as old as 12-13 Gyr, but our models have problems matching the spectral energy distributions of these objects. There are only two halo WD candidates in our sample. However, trigonometric parallax observations are required for accurate mass and age determinations and to confirm their membership in the halo.

Kilic, Mukremin [Smithsonian Astrophysical Observatory, 60 Garden Street, Cambridge, MA 02138 (United States); Leggett, S. K. [Gemini Observatory, 670 N. A'ohoku Place, Hilo, HI 96720 (United States); Tremblay, P.-E.; Bergeron, P. [Departement de Physique, Universite de Montreal, C.P. 6128, Succursale Centre-Ville, Montreal, Quebec H3C 3J7 (Canada); Von Hippel, Ted [Physics Department, Siena College, 515 Loudon Road, Loudonville, NY 12211 (United States); Harris, Hugh C.; Munn, Jeffrey A. [U.S. Naval Observatory, Flagstaff Station, 10391 W. Naval Observatory Road, Flagstaff, AZ 86001 (United States); Williams, Kurtis A. [Department of Astronomy, 1 University Station C1400, Austin, TX 78712 (United States); Gates, Evalyn [Kavli Institute for Cosmological Physics and Department of Astronomy and Astrophysics, The University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637 (United States); Farihi, J., E-mail: mkilic@cfa.harvard.ed [Department of Physics and Astronomy, University of Leicester, Leicester LE1 7RH (United Kingdom)

2010-09-15T23:59:59.000Z

176

Mesoscale phenomena in solutions of 3-methylpyridine, heavy water, and an antagonistic salt  

E-Print Network [OSTI]

We have investigated controversial issues regarding the mesoscale behavior of 3-methylpyridine (3MP), heavy water, and sodium tetraphenylborate (NaBPh4) solutions by combining results obtained from dynamic light scattering (DLS) and small-angle neutron scattering (SANS). We have addressed three questions: (i) what is the origin of the mesoscale inhomogeneities (order of 100 nm in size) manifested by the "slow mode" in DLS? (ii) Is the periodic structure observed from SANS an inherent property of this system? (iii) What is the universality class of critical behavior in this system? Our results confirm that the "slow mode" observed from DLS experiments corresponds to long-lived, highly stable mesoscale droplets (order of 100 nm in size), which occur only when the solute (3MP) is contaminated by hydrophobic impurities. SANS data confirm the presence of a periodic structure with a periodicity of about 10 nm. This periodic structure cannot be eliminated by nanopore filtration and thus is indeed an inherent solution property. The critical behavior of this system, in the range of concentration and temperatures investigated by DLS experiments, indicates that the criticality belongs to the universality class of the 3-dimensional Ising model.

Jan Leys; Deepa Subramanian; Eva Rodezno; Boualem Hammouda; Mikhail A. Anisimov

2013-08-22T23:59:59.000Z

177

Summary of the March 25--26, 1991 atmospheric model working meeting. Hanford Environmental Dose Reconstruction Project  

SciTech Connect (OSTI)

Atmospheric transport and diffusion calculations for the initial phase of the Hanford Environmental Dose Reconstruction (HEDR) Project were made using the MESOILT2 computer code (Ramsdell and Burk 1991). This code implemented a Lagrangian trajectory, puff dispersion model using components from other models designed primarily for regulatory applications. Uncertainty in the dispersion calculations was estimated following model calculations. The results of the atmospheric dispersion calculations were summarized in frequency distributions by location for use in preliminary dose calculations.

Ramsdell, J.V.

1992-07-01T23:59:59.000Z

178

White dwarf atmosphere models with Ly-$?$ opacity in the analysis of the white dwarf cooling sequence of NGC 6397  

E-Print Network [OSTI]

We discuss the importance of pure hydrogen white dwarf atmosphere models with Ly-$\\rm \\alpha$ far red wing opacity in the analysis of the white dwarf cooling sequence of the globular cluster NGC 6397. Our recently improved atmosphere models account for the previously missing opacity from the Ly-$\\rm \\alpha$ hydrogen line broadened by collisions of the absorbing hydrogen atoms with molecular and atomic hydrogen. These models are the first that well reproduce the UV colors and spectral energy distributions of cool white dwarfs with $T_{\\rm eff}white dwarf cooling sequence using atmosphere models that do not include the correct Ly-$\\alpha$ opacity is underestimated by $\\sim 0.5$ Gyr. Our analysis shows that it is essential to use white dwarf atmosphere models with Ly-$\\rm \\alpha$ opacity for precise dating of old stellar populations from white dwarf cooling sequences.

Piotr M. Kowalski

2007-08-28T23:59:59.000Z

179

Modeling dust as component minerals in the Community Atmosphere Model: development of framework and impact on radiative forcing  

SciTech Connect (OSTI)

The mineralogy of desert dust is important due to its effect on radiation, clouds and biogeochemical cycling of trace nutrients. This study presents the simulation of dust radiative forcing as a function of both mineral composition and size at the global scale using mineral soil maps for estimating emissions. Externally mixed mineral aerosols in the bulk aerosol module in the Community Atmosphere Model version 4 (CAM4) and internally mixed mineral aerosols in the modal aerosol module in the Community Atmosphere Model version 5.1 (CAM5) embedded in the Community Earth System Model version 1.0.5 (CESM) are speciated into common mineral components in place of total dust. The simulations with mineralogy are compared to available observations of mineral atmospheric distribution and deposition along with observations of clear-sky radiative forcing efficiency. Based on these simulations, we estimate the all-sky direct radiative forcing at the top of the atmosphere as +0.05Wm?2 for both CAM4 and CAM5 simulations with mineralogy and compare this both with simulations of dust in release versions of CAM4 and CAM5 (+0.08 and +0.17Wm?2) and of dust with optimized optical properties, wet scavenging and particle size distribution in CAM4 and CAM5, ?0.05 and ?0.17Wm?2, respectively. The ability to correctly include the mineralogy of dust in climate models is hindered by its spatial and temporal variability as well as insufficient global in-situ observations, incomplete and uncertain source mineralogies and the uncertainties associated with data retrieved from remote sensing methods.

Scanza, Rachel; Mahowald, N.; Ghan, Steven J.; Zender, C. S.; Kok, J. F.; Liu, Xiaohong; Zhang, Y.; Albani, Samuel

2015-01-01T23:59:59.000Z

180

Comment on "Time Step Sensitivity of Nonlinear Atmospheric Models: Numerical Convergence, Truncation Error Growth, and Ensemble Design" Teixeira et al. (2007)  

E-Print Network [OSTI]

Comment on "Time Step Sensitivity of Nonlinear Atmospheric Models: Numerical Convergence, Truncation Error Growth, and Ensemble Design" Teixeira et al.

Lun-Shin Yao; Dan Hughes

2007-04-26T23:59:59.000Z

Note: This page contains sample records for the topic "atmospheric mesoscale model" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

The new GFDL global atmosphere and land model AM2/LM2: Evaluation with prescribed SST simulations  

E-Print Network [OSTI]

The new GFDL global atmosphere and land model AM2/LM2: Evaluation with prescribed SST simulations climatology, and components from previous models used at GFDL. The land model, known as LM2, includes soil of the coupled model AM2/LM2 is evaluated with a series of prescribed sea-surface temperature (SST) simulations

Bretherton, Chris

182

Testing the atmospheric dispersion model of CSA N288.1 with site-specific data  

E-Print Network [OSTI]

The atmospheric dispersion component of CSA Standard N288. 1, which provides guidelines for calculating derived release limits, has been tested. Long-term average concentrations of tritium in air were predicted using site-specific release rates and meteorological data and compared with measured concentrations at 43 monitoring sites at all CANDU stations in Canada. The predictions correlate well with the observations but were found to be conservative, overestimating by about 50% on average. The model overpredicted 84% of the time, with the highest prediction lying a factor of 5.5 above the corresponding observation. The model underpredicted the remaining 16% of the time, with the lowest prediction about one-half of the corresponding measurement. Possible explanations for this bias are discussed but no single reason appears capable of accounting for the discrepancy. Rather, the tendency to overprediction seems to result from the cumulative effects of a number of small conservatisms in the model. The model predi...

Chouhan, S L

2001-01-01T23:59:59.000Z

183

A Three-Dimensional Ocean-Seaice-Carbon Cycle Model and its Coupling to a Two-Dimensional Atmospheric Model: Uses in Climate Change Studies  

E-Print Network [OSTI]

We describe the coupling of a three-dimensional ocean circulation model, with explicit thermodynamic seaice and ocean carbon cycle representations, to a two-dimensional atmospheric/land model. This coupled system has been ...

Dutkiewicz, Stephanie.

184

ISO-SWS calibration and the accurate modelling of cool-star atmospheres: I. Method  

E-Print Network [OSTI]

A detailed spectroscopic study of the ISO-SWS data of the red giant Alpha Tau is presented, which enables not only the accurate determination of the stellar parameters of Alpha Tau, but also serves as a critical review of the ISO-SWS calibration. This study is situated in a broader context of an iterative process in which both accurate observations of stellar templates and cool star atmosphere models are involved to improve the ISO-SWS calibration process as well as the theoretical modelling of stellar atmospheres. Therefore a sample of cool stars, covering the whole A0 -- M8 spectral classification, has been observed in order to disentangle calibration problems and problems in generating the theoretical models and corresponding synthetic spectrum. By using stellar parameters found in the literature large discrepancies were seen between the ISO-SWS data and the generated synthetic spectrum of Alpha Tau. A study of the influence of various stellar parameters on the theoretical models and synthetic spectra, in conjunction with the Kolmogorov-Smirnov test to evaluate objectively the goodness-of-fit, enables us to pin down the stellar parameters with a high accuracy: Teff = 3850 +/- 70 K, log g = 1.50 +/- 0.15, M = 2.3 +/- 0.8 Msun, z = -0.15 +/- 0.20 dex, microturbulence = 1.7 +/- 0.3 km/s, 12C/13C= 10 +/- 1, abundance of C = 8.35 +/- 0.20 dex, abundance of N= 8.35 +/- 0.25 dex, abundance of O = 8.83 +/- 0.15 dex and the angular diameter is 20.77 +/- 0.83 mas. These atmospheric parameters were then compared with the results provided by other authors using other methods and/or spectra.

L. Decin; C. Waelkens; K. Eriksson; B. Gustafsson; B. Plez; A. J. Sauval; W. Van Assche; B. Vandenbussche

2000-08-21T23:59:59.000Z

185

VALDRIFT 1.0: A valley atmospheric dispersion model with deposition  

SciTech Connect (OSTI)

VALDRIFT version 1.0 is an atmospheric transport and diffusion model for use in well-defined mountain valleys. It is designed to determine the extent of ddft from aedal pesticide spraying activities, but can also be applied to estimate the transport and diffusion of various air pollutants in valleys. The model is phenomenological -- that is, the dominant meteorological processes goveming the behavior of the valley atmosphere are formulated explicitly in the model, albeit in a highly parameterized fashion. The key meteorological processes treated are: (1) nonsteady and nonhomogeneous along-valley winds and turbulent diffusivities, (2) convective boundary layer growth, (3) inversion descent, (4) noctumal temperature inversion breakup, and (5) subsidence. The model is applicable under relatively cloud-free, undisturbed synoptic conditions and is configured to operate through one diumal cycle for a single valley. The inputs required are the valley topographical characteristics, pesticide release rate as a function of time and space, along-valley wind speed as a function of time and space, temperature inversion characteristics at sunrise, and sensible heat flux as a function of time following sunrise. Default values are provided for certain inputs in the absence of detailed observations. The outputs are three-dimensional air concentration and ground-level deposition fields as a function of time.

Allwine, K.J.; Bian, X.; Whiteman, C.D.

1995-05-01T23:59:59.000Z

186

COLLABORATIVE RESEARCH: CONTINUOUS DYNAMIC GRID ADAPTATION IN A GLOBAL ATMOSPHERIC MODEL: APPLICATION AND REFINEMENT  

SciTech Connect (OSTI)

This project had goals of advancing the performance capabilities of the numerical general circulation model EULAG and using it to produce a fully operational atmospheric global climate model (AGCM) that can employ either static or dynamic grid stretching for targeted phenomena. The resulting AGCM combined EULAGâ??s advanced dynamics core with the â??physicsâ? of the NCAR Community Atmospheric Model (CAM). Effort discussed below shows how we improved model performance and tested both EULAG and the coupled CAM-EULAG in several ways to demonstrate the grid stretching and ability to simulate very well a wide range of scales, that is, multi-scale capability. We leveraged our effort through interaction with an international EULAG community that has collectively developed new features and applications of EULAG, which we exploited for our own work summarized here. Overall, the work contributed to over 40 peer- reviewed publications and over 70 conference/workshop/seminar presentations, many of them invited.

Prusa, Joseph

2012-05-08T23:59:59.000Z

187

The Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP): Overview and Description of Models, Simulations and Climate Diagnostics  

SciTech Connect (OSTI)

The Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP) consists of a series of timeslice experiments targeting the long-term changes in atmospheric composition between 1850 and 2100, with the goal of documenting radiative forcing and the associated composition changes. Here we introduce the various simulations performed under ACCMIP and the associated model output. The ACCMIP models have a wide range of horizontal and vertical resolutions, vertical extent, chemistry schemes and interaction with radiation and clouds. While anthropogenic and biomass burning emissions were specified for all time slices in the ACCMIP protocol, it is found that the natural emissions lead to a significant range in emissions, mostly for ozone precursors. The analysis of selected present-day climate diagnostics (precipitation, temperature, specific humidity and zonal wind) reveals biases consistent with state-of-the-art climate models. The model-to-model comparison of changes in temperature, specific humidity and zonal wind between 1850 and 2000 and between 2000 and 2100 indicates mostly consistent results, but with outliers different enough to possibly affect their representation of climate impact on chemistry.

Lamarque, J.-F.; Shindell, Drew; Josse, B.; Young, P. J.; Cionni, I.; Eyring, Veronika; Bergmann, D.; Cameron-Smith, Philip; Collins, W. J.; Doherty, R.; Dalsoren, S.; Faluvegi, G.; Folberth, G.; Ghan, Steven J.; Horowitz, L.; Lee, Y. H.; MacKenzie, I. A.; Nagashima, T.; Naik, Vaishali; Plummer, David; Righi, M.; Rumbold, S.; Schulz, M.; Skeie, R. B.; Stevenson, D. S.; Strode, S.; Sudo, K.; Szopa, S.; Voulgarakis, A.; Zeng, G.

2013-02-07T23:59:59.000Z

188

E-Print Network 3.0 - atmospheric mercury models Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

or distribute Atmospheric and Geologic Sources of Mercury Kejimkujik Park has no direct industrial... is atmospheric deposition. The global ... Source: O'Driscoll, Nelson -...

189

E-Print Network 3.0 - atmospheric emissions modeling Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

well as "back radiation" downward to the surface. The atmosphere also... .e., the greenhouse effect, is included via the atmospheric ... Source: Noone, David - Program in...

190

Carbon monoxide in the solar atmosphere I. Numerical method and two-dimensional models  

E-Print Network [OSTI]

The radiation hydrodynamic code CO5BOLD has been supplemented with the time-dependent treatment of chemical reaction networks. Advection of particle densities due to the hydrodynamic flow field is also included. The radiative transfer is treated frequency-independently, i.e. grey, so far. The upgraded code has been applied to two-dimensional simulations of carbon monoxide (CO) in the non-magnetic solar photosphere and low chromosphere. For this purpose a reaction network has been constructed, taking into account the reactions which are most important for the formation and dissociation of CO under the physical conditions of the solar atmosphere. The network has been strongly reduced to 27 reactions, involving the chemical species H, H2, C, O, CO, CH, OH, and a representative metal. The resulting CO number density is highest in the cool regions of the reversed granulation pattern at mid-photospheric heights and decreases strongly above. There, the CO abundance stays close to a value of 8.3 on the usual logarithmic abundance scale with [H]=12 but is reduced in hot shock waves which are a ubiquitous phenomenon of the model atmosphere. For comparison, the corresponding equilibrium densities have been calculated, based on the reaction network but also under assumption of instantaneous chemical equilibrium by applying the Rybicki & Hummer (RH) code by Uitenbroek (2001). Owing to the short chemical timescales, the assumption holds for a large fraction of the atmosphere, in particular the photosphere. In contrast, the CO number density deviates strongly from the corresponding equilibrium value in the vicinity of chromospheric shock waves. Simulations with altered reaction network clearly show that the formation channel via hydroxide (OH) is the most important one under the conditions of the solar atmosphere.

S. Wedemeyer-Boehm; I. Kamp; J. Bruls; B. Freytag

2005-03-23T23:59:59.000Z

191

COLLABORATIVE RESEARCH: CONTINUOUS DYNAMIC GRID ADAPTATION IN A GLOBAL ATMOSPHERIC MODEL: APPLICATION AND REFINEMENT  

SciTech Connect (OSTI)

This project had goals of advancing the performance capabilities of the numerical general circulation model EULAG and using it to produce a fully operational atmospheric global climate model (AGCM) that can employ either static or dynamic grid stretching for targeted phenomena. The resulting AGCM combined EULAG's advanced dynamics core with the "physics" of the NCAR Community Atmospheric Model (CAM). Effort discussed below shows how we improved model performance and tested both EULAG and the coupled CAM-EULAG in several ways to demonstrate the grid stretching and ability to simulate very well a wide range of scales, that is, multi-scale capability. We leveraged our effort through interaction with an international EULAG community that has collectively developed new features and applications of EULAG, which we exploited for our own work summarized here. Overall, the work contributed to over 40 peer-reviewed publications and over 70 conference/workshop/seminar presentations, many of them invited. 3a. EULAG Advances EULAG is a non-hydrostatic, parallel computational model for all-scale geophysical flows. EULAG's name derives from its two computational options: EULerian (flux form) or semi-LAGrangian (advective form). The model combines nonoscillatory forward-in-time (NFT) numerical algorithms with a robust elliptic Krylov solver. A signature feature of EULAG is that it is formulated in generalized time-dependent curvilinear coordinates. In particular, this enables grid adaptivity. In total, these features give EULAG novel advantages over many existing dynamical cores. For EULAG itself, numerical advances included refining boundary conditions and filters for optimizing model performance in polar regions. We also added flexibility to the model's underlying formulation, allowing it to work with the pseudo-compressible equation set of Durran in addition to EULAG's standard anelastic formulation. Work in collaboration with others also extended the demonstrated range of validity of soundproof models, showing that they are more broadly applicable than some had previously thought. Substantial testing of EULAG included application and extension of the Jablonowski-Williamson baroclinic wave test - an archetype of planetary weather - and further analysis of multi-scale interactions arising from collapse of temperature fronts in both the baroclinic wave test and simulations of the Held-Suarez idealized climate. These analyses revealed properties of atmospheric gravity waves not seen in previous work and further demonstrated the ability of EULAG to simulate realistic behavior over several orders of magnitude of length scales. Additional collaborative work enhanced capability for modeling atmospheric flows with adaptive moving meshes and demonstrated the ability of EULAG to move into petascale computing. 3b. CAM-EULAG Advances We have developed CAM-EULAG in collaboration with former project postdoc, now University of Cape Town Assistant Professor, Babatunde Abiodun. Initial study documented good model performance in aqua-planet simulations. In particular, we showed that the grid adaptivity (stretching) implemented in CAM-EULAG allows higher resolution in selected regions without causing anomalous behavior such as spurious wave reflection. We then used the stretched-grid version to analyze simulated extreme precipitation events in West Africa, comparing the precipitation and event environment with observed behavior. The model simulates fairly well the spatial scale and the interannual and intraseasonal variability of the extreme events, although its extreme precipitation intensity is weaker than observed. In addition, both observations and the simulations show possible forcing of extreme events by African easterly waves. 3c. Other Contributions Through our collaborations, we have made contributions to a wide range of outcomes. For research focused on terrestrial behavior, these have included (1) upwind schemes for gas dynamics, (2) a nonlinear perspective on the dynamics of the Madden-Julian Oscillation, (3) numerical realism of thermal co

Gutowski, William J.; Prusa, Joseph M.; Smolarkiewicz, Piotr K.

2012-05-08T23:59:59.000Z

192

Atmospheric transmittance model for a solar beam propagating between a heliostat and a receiver  

SciTech Connect (OSTI)

This report presents formulae that provide reliable estimates of the percent energy loss P/sub L/ (or, equivalently, the transmittance tau) of a solar beam propagating between a heliostat and a receiver. These formulae are wavelength-independent, functional fits to the tabulated results of Vittitoe and Biggs, which in turn are the results of numerical integrations of spectral transmittance data calculated with the aid of the computer code LOWTRAN 3. The formulae allow for interpolation and extrapolation and have a form characteristic of atmospheric transmittance models.

Pitman, C.L.; Vant-Hull, L.L.

1984-02-01T23:59:59.000Z

193

Evaluation of the Multi-scale Modeling Framework Using Data from the Atmospheric Radiation Measurement Program  

SciTech Connect (OSTI)

One of the goals of the Atmospheric Radiation Measurement (ARM) program is to provide long-term observations for evaluating and improving cloud and radiation treatment in global climate models. Unfortunately, the traditional parametric approach of diagnosing cloud and radiation properties for gridcells that are tens to hundreds kilometers across from large-scale model fields is not well suited for comparison with time series of ground based observations at selected locations. A recently emerging approach called a multi-scale modeling framework (MMF) has shown promise to bridge the scale gap. The MMF consists of a two-dimensional or small three-dimensional cloud resolving model (CRM) embedded into each grid column of the Community Atmospheric Model (CAM), thereby computing cloud properties at a scale that is more consistent with observations. We present a comparison of data from two ARM sites, one at the Southern Great Plains (SGP) in Oklahoma and one at Nauru Island in the Tropical Western Pacific (TWP) region, with output from both the CAM and MMF. Two sets of one year long simulations are considered: one using climatological sea surface temperatures (SST) and another using 1999 SST. Each set includes a run with the MMF as well as the CAM run with traditional or standard cloud and radiation treatment. Time series of cloud fraction, precipitation intensity, and downwelling solar radiation flux at the surface are statistically analyzed. For the TWP site, nearly all parameters of frequency distributions of these variables from the MMF run are shown to be more consistent with observation than those from the CAM run. This change is attributed to the improved representation of convective clouds in the MMF compared to the conventional climate model. For the SGP, the MMF shows little to no improvement in predicting the same quantities. Possible causes of this lack of improvement are discussed.

Ovtchinnikov, Mikhail; Ackerman, Thomas P.; Marchand, Roger T.; Khairoutdinov, Marat

2006-05-01T23:59:59.000Z

194

Posters Single-Column Model for Atmospheric Radiation Measurement Sites: Model  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 - September 2006PhotovoltaicSeptember 22, 2014SocietyJ. Dudhia51 Posters75517733

195

The Lagrangian particle dispersion model FLEXPART-WRF VERSION 3.1  

SciTech Connect (OSTI)

The Lagrangian particle dispersion model FLEXPART was originally designed for cal- culating long-range and mesoscale dispersion of air pollutants from point sources, such as after an accident in a nuclear power plant. In the meantime FLEXPART has evolved into a comprehensive tool for atmospheric transport modeling and analysis at different scales. This multiscale need from the modeler community has encouraged new developments in FLEXPART. In this document, we present a version that works with the Weather Research and Forecasting (WRF) mesoscale meteoro- logical model. Simple procedures on how to run FLEXPART-WRF are presented along with special options and features that differ from its predecessor versions. In addition, test case data, the source code and visualization tools are provided to the reader as supplementary material.

Brioude, J.; Arnold, D.; Stohl, A.; Cassiani, M.; Morton, Don; Seibert, P.; Angevine, W. M.; Evan, S.; Dingwell, A.; Fast, Jerome D.; Easter, Richard C.; Pisso, I.; Bukhart, J.; Wotawa, G.

2013-11-01T23:59:59.000Z

196

Evaluation of the Multi-Scale Modeling Framework using Data from the Atmospheric Radiation Measurement Program  

SciTech Connect (OSTI)

One of the goals of the Atmospheric Radiation Measurement (ARM) program was to provide long-term observations for evaluation of cloud and radiation treatment in global climate models. Unfortunately, traditional parametric approach of diagnosing cloud and radiation properties from large-scale model fields is not well suited for comparison with observed time series at selected locations. A recently emerging approach called the multi-scale modeling framework (MMF) has shown promise to bridge the gap. MMF consists of a two-dimensional cloud system resolving model (CSRM) embedded into each CAM grid column of the Community Atmospheric Model (CAM), thereby computing cloud properties at a scale that is more consistent with observations. Because the approach is computationally expensive only limited simulations have been carried out. In this presentation, we will present a comparison of data from two ARM sites, one at the Southern Great Plains (SGP) in Oklahoma and one at Nauru island in the Tropical Western Pacific (TWP) region, with output from both CAM and MMF. Two sets of one year long simulations are considered: one using climatological sea surface temperatures (SST) and another using 1999 SST. Each set includes a run with MMF as well as CAM run with traditional or standard cloud and radiation treatment. Time series of cloud fraction, precipitation intensity, and downwelling solar radiation flux at the surface are statistically analyzed. For the TWP site, nearly all parameters of frequency distributions of these variables from MMF run are shown to be more consistent with observation than those from CAM run. For the SGP, the improvements are marginal.

Ovchinnikov, Mikhail; Ackerman, Thomas P.; Marchand, Roger T.; Khairoutdinov, Marat

2004-07-01T23:59:59.000Z

197

3D Atmospheric Radiative Transfer for Cloud System-Resolving Models: Forward Modelling and Observations  

SciTech Connect (OSTI)

Utilization of cloud-resolving models and multi-dimensional radiative transfer models to investigate the importance of 3D radiation effects on the numerical simulation of cloud fields and their properties.

Howard Barker; Jason Cole

2012-05-17T23:59:59.000Z

198

Development of an Atmospheric Climate Model with Self-Adapting Grid and Physics  

SciTech Connect (OSTI)

This project was targeting the development of a computational approach that would allow resolving cloud processes on small-scales within the framework of the most recent version of the NASA/NCAR Finite-Volume Community Atmospheric Model (FVCAM). The FVCAM is based on the multidimensional Flux-Form Semi-Lagrangian (FFSL) dynamical core and uses a ?vertically Lagrangian? finite-volume (FV) representation of the model equations with a mass-conserving re-mapping algorithm. The Lagrangian coordinate requires a remapping of the Lagrangian volume back to Eulerian coordinates to restore the original resolution and keep the mesh from developing distortions such as layers with overlapping interfaces. The main objectives of the project were, first, to develop the 3D library which allows refinement and coarsening of the model domain in spherical coordinates, and second, to develop a non-hydrostatic code for calculation of the model variables within the refined areas that could be seamlessly incorporated with the hydrostatic finite volume dynamical core when higher resolution is wanted. We also updated the aerosol simulation model in CAM in order to ready the model for the treatment of aerosol/cloud interactions.

Penner, Joyce E. [University of Michigan] University of Michigan

2013-08-10T23:59:59.000Z

199

ISO-SWS calibration and the accurate modelling of cool-star atmospheres - II. General results  

E-Print Network [OSTI]

The fine calibration of the ISO-SWS detectors (Infrared Space Observatory - Short Wavelength Spectrometer) has proven to be a delicate problem. We therefore present a detailed spectroscopic study in the 2.38 -- 12 micron wavelength range of a sample of 16 A0 -- M2 stars used for the calibration of ISO-SWS. By investigating the discrepancies between the ISO-SWS data of these sources, the theoretical predictions of their spectra, the high-resolution FTS-KP (Kitt Peak) spectrum of Alpha Boo and the solar FTS-ATMOS (Atmospheric Trace Molecule Spectroscopy) spectrum, both calibration problems and problems in computing the theoretical models and the synthetic spectra are revealed. The underlying reasons for these problems are sought for and the impact on the further calibration of ISO-SWS and on the theoretical modelling is discussed extensively.

L. Decin; B. Vandenbussche; C. Waelkens; K. Eriksson; B. Gustafsson; B. Plez; A. J. Sauval; K. Hinkle

2002-07-29T23:59:59.000Z

200

Efficiency and Sensitivity Analysis of Observation Networks for Atmospheric Inverse Modelling with Emissions  

E-Print Network [OSTI]

The controllability of advection-diffusion systems, subject to uncertain initial values and emission rates, is estimated, given sparse and error affected observations of prognostic state variables. In predictive geophysical model systems, like atmospheric chemistry simulations, different parameter families influence the temporal evolution of the system.This renders initial-value-only optimisation by traditional data assimilation methods as insufficient. In this paper, a quantitative assessment method on validation of measurement configurations to optimize initial values and emission rates, and how to balance them, is introduced. In this theoretical approach, Kalman filter and smoother and their ensemble based versions are combined with a singular value decomposition, to evaluate the potential improvement associated with specific observational network configurations. Further, with the same singular vector analysis for the efficiency of observations, their sensitivity to model control can be identified by deter...

Wu, Xueran; Jacob, Birgit

2015-01-01T23:59:59.000Z

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201

A New Ensemble of Perturbed-Input-Parameter Simulations by the Community Atmosphere Model  

SciTech Connect (OSTI)

Uncertainty quantification (UQ) is a fundamental challenge in the numerical simulation of Earth's weather and climate, and other complex systems. It entails much more than attaching defensible error bars to predictions: in particular it includes assessing low-probability but high-consequence events. To achieve these goals with models containing a large number of uncertain input parameters, structural uncertainties, etc., raw computational power is needed. An automated, self-adapting search of the possible model configurations is also useful. Our UQ initiative at the Lawrence Livermore National Laboratory has produced the most extensive set to date of simulations from the US Community Atmosphere Model. We are examining output from about 3,000 twelve-year climate simulations generated with a specialized UQ software framework, and assessing the model's accuracy as a function of 21 to 28 uncertain input parameter values. Most of the input parameters we vary are related to the boundary layer, clouds, and other sub-grid scale processes. Our simulations prescribe surface boundary conditions (sea surface temperatures and sea ice amounts) to match recent observations. Fully searching this 21+ dimensional space is impossible, but sensitivity and ranking algorithms can identify input parameters having relatively little effect on a variety of output fields, either individually or in nonlinear combination. Bayesian statistical constraints, employing a variety of climate observations as metrics, also seem promising. Observational constraints will be important in the next step of our project, which will compute sea surface temperatures and sea ice interactively, and will study climate change due to increasing atmospheric carbon dioxide.

Covey, C; Brandon, S; Bremer, P T; Domyancis, D; Garaizar, X; Johannesson, G; Klein, R; Klein, S A; Lucas, D D; Tannahill, J; Zhang, Y

2011-10-27T23:59:59.000Z

202

HGSYSTEMUF6. Model for Simulating Dispersion due to Atmospheric Release of UF6  

SciTech Connect (OSTI)

HGSYSTEMUF6 is a suite of models designed for use in estimating consequences associated with accidental, atmospheric release of Uranium Hexafluoride (UF6) and its reaction products, namely Hydrogen Fluoride (HF), and other non-reactive contaminants which are either negatively, neutrally, or positively buoyant. It is based on HGSYSTEM Version 3.0 of Shell Research LTD., and contains specific algorithms for the treatment of UF6 chemistry and thermodynamics. HGSYSTEMUF6 contains algorithms for the treatment of dense gases, dry and wet deposition, effects due to the presence of buildings (canyon and wake), plume lift-off, and the effects of complex terrain. The models components of the suite include (1) AEROPLUME/RK, used to model near-field dispersion from pressurized two-phase jet releases of UF6 and its reaction products, (2) HEGADAS/UF6 for simulating dense, ground based release of UF6, (3) PGPLUME for simulation of passive, neutrally buoyant plumes (4) UF6Mixer for modeling warm, potentially reactive, ground-level releases of UF6 from buildings, and (5) WAKE, used to model elevated and ground-level releases into building wake cavities of non-reactive plumes that are either neutrally or positively buoyant.

Hanna, G [George Mason University, (United States); Chang, J.C. [Earthtech, Inc., (United States); Zhang, J.X. [BlazeTech Corporation, (United States); Bloom, S.G. [Lockheed Martin Energy Systems, Oak Ridge, TN (United States); Goode, W.D. Jr [Bechtel Jacobs Company, Oak Ridge, TN (United States); Lombardi, D.A. [JBF Associates, (United States); Yambert, M.W. [LMERC, Oak Ridge, TN (United States)

1998-08-01T23:59:59.000Z

203

Observed Scaling in Clouds and Precipitation and Scale Incognizance in Regional to Global Atmospheric Models  

SciTech Connect (OSTI)

We use observations of robust scaling behavior in clouds and precipitation to derive constraints on how partitioning of precipitation should change with model resolution. Our analysis indicates that 90-99% of stratiform precipitation should occur in clouds that are resolvable by contemporary climate models (e.g., with 200 km or finer grid spacing). Furthermore, this resolved fraction of stratiform precipitation should increase sharply with resolution, such that effectively all stratiform precipitation should be resolvable above scales of ~50 km. We show that the Community Atmosphere Model (CAM) and the Weather Research and Forecasting (WRF) model also exhibit the robust cloud and precipitation scaling behavior that is present in observations, yet the resolved fraction of stratiform precipitation actually decreases with increasing model resolution. A suite of experiments with multiple dynamical cores provides strong evidence that this `scale-incognizant' behavior originates in one of the CAM4 parameterizations. An additional set of sensitivity experiments rules out both convection parameterizations, and by a process of elimination these results implicate the stratiform cloud and precipitation parameterization. Tests with the CAM5 physics package show improvements in the resolution-dependence of resolved cloud fraction and resolved stratiform precipitation fraction.

O'Brien, Travis A.; Li, Fuyu; Collins, William D.; Rauscher, Sara; Ringler, Todd; Taylor, Mark; Hagos, Samson M.; Leung, Lai-Yung R.

2013-12-01T23:59:59.000Z

204

A hydrodynamic model for asymmetric explosions of rapidly rotating collapsing supernovae with a toroidal atmosphere  

E-Print Network [OSTI]

We numerically solved the two-dimensional axisymmetric hydrodynamic problem of the explosion of a low-mass neutron star in a circular orbit. In the initial conditions, we assumed a nonuniform density distribution in the space surrounding the collapsed iron core in the form of a stationary toroidal atmosphere that was previously predicted analytically and computed numerically. The con?guration of the exploded neutron star itself was modeled by a torus with a circular cross section whose central line almost coincided with its circular orbit. Using an equation of state for the stellar matter and the toroidal atmosphere in which the nuclear statistical equilibrium conditions were satisfied, we performed a series of numerical calculations that showed the propagation of a strong divergent shock wave with a total energy of 0.2x10^51 erg at initial explosion energy release of 1.0x10^51 erg. In our calculations, we rigorously took into account the gravitational interaction, including the attraction from a higher-mass (1.9M_solar) neutron star located at the coordinate origin, in accordance with the rotational explosion mechanism for collapsing supernovae.W e compared in detail our results with previous similar results of asymmetric supernova explosion simulations and concluded that we found a lower limit for the total explosion energy.

V. S. Imshennik; K. V. Manukovskii

2004-11-16T23:59:59.000Z

205

Characterization of Caribbean Meso-Scale Eddies Jose M. Lopez  

E-Print Network [OSTI]

Characterization of Caribbean Meso-Scale Eddies Jose M. Lopez Department of Marine Sciences, P-term goal is to improve predictivity of physical, biogeochemical and optical properties of Eastern Caribbean, biological and optical variables across frontal and eddy boundaries in the Eastern Caribbean Sea · To develop

Gilbes, Fernando

206

Molecule-Mimetic Chemistry and Mesoscale Self-Assembly  

E-Print Network [OSTI]

Molecule-Mimetic Chemistry and Mesoscale Self-Assembly NED B. BOWDEN, MARCUS WECK, INSUNG S. CHOI systems. We suggest that it will be possible to develop complex structures composed of "objects" that self-assemble, shape recognition, and size exclusion can be used to guide the self-assembly of these objects

Prentiss, Mara

207

LANSCE School on Neutron Scattering: Materials at the Mesoscale  

E-Print Network [OSTI]

1 11th LANSCE School on Neutron Scattering: Materials at the Mesoscale Lujan Center Los Alamos. Please name the applicant for admission to the 11th LANSCE School on Neutron Scattering: Last, First LANSCE School on Neutron Scattering including: drive and motivation, ability to work with others

208

Acidbase chemical reaction model for nucleation rates in the polluted atmospheric boundary layer  

E-Print Network [OSTI]

Atmospheric Sciences Division, Brookhaven National Laboratory, Upton, NY 11973; f Sustainable Energy Systems Group, Environmental Energy Technologies Division, E. O. Lawrence Berkeley National Laboratory, Berkeley agreement with measurements from Mexico City and Atlanta. amines | atmospheric aerosol | climate forcing

209

Climate Sensitivity of the Community Climate System Model, Version 4 Atmospheric Sciences, University of Washington, Seattle, Washington  

E-Print Network [OSTI]

Climate Sensitivity of the Community Climate System Model, Version 4 C. M. BITZ Atmospheric climate sensitivity of the Community Climate System Model, version 4 (CCSM4) is 3.208C for 18 horizontal). The transient climate sensitivity of CCSM4 at 18 resolution is 1.728C, which is about 0.28C higher than in CCSM3

Reif, Rafael

210

Numerical simulations of mesoscale precipitation systems. Final progress report, 1 April-30 June 1981  

SciTech Connect (OSTI)

A numerical model designed for the study of mesoscale weather phenomena is presented. It is a three-dimensional, time-dependent model based upon a mesoscale primitive-equation system, and it includes parameterizations of cloud and precipitation processes, boundary-layer transfers, and ground surface energy and moisture budgets. This model was used to simulate the lake-effect convergence over and in the lee of Lake Michigan in late fall and early winter. The lake-effect convergence is created in advected cold air as it moves first from cold land to the warm constant-temperature lake surface, and then on to cold land. A numerical experiment with a prevailing northwesterly wind is conducted for a period of twelve hours. Two local maxima of the total precipitation are observed along the eastern shore of Lake Michigan. The results in this hypothetical case correspond quite well to the observed precipitation produced by a real event in which the hypothetical conditions are approximately fulfilled.

Dingle, A.N.

1982-05-12T23:59:59.000Z

211

A Grid of NLTE Line-Blanketed Model Atmospheres of Early B-type Stars  

E-Print Network [OSTI]

We have constructed a comprehensive grid of 1540 metal line-blanketed, NLTE, plane-parallel, hydrostatic model atmospheres for the basic parameters appropriate to early B-type stars. The BSTAR2006 grid considers 16 values of effective temperatures, 15,000 K grid complements our earlier OSTAR2002 grid of O-type stars (Lanz & Hubeny, 2003, ApJS, 146, 417). The paper contains a description of the BSTAR2006 grid and some illustrative examples and comparisons. NLTE ionization fractions, bolometric corrections, radiative accelerations, and effective gravities are obtained over the parameter range covered by the grid. By extrapolating radiative accelerations, we have determined an improved estimate of the Eddington limit in absence of rotation between 55,000 and 15,000 K. The complete BSTAR2006 grid is available at the TLUSTY website (http://nova.astro.umd.edu).

Thierry Lanz; Ivan Hubeny

2006-11-29T23:59:59.000Z

212

Spatial Variation of Soil Type and Soil Moisture in the Regional Atmospheric Modeling System  

SciTech Connect (OSTI)

Soil characteristics (texture and moisture) are typically assumed to be initially constant when performing simulations with the Regional Atmospheric Modeling System (RAMS). Soil texture is spatially homogeneous and time-independent, while soil moisture is often spatially homogeneous initially, but time-dependent. This report discusses the conversion of a global data set of Food and Agriculture Organization (FAO) soil types to RAMS soil texture and the subsequent modifications required in RAMS to ingest this information. Spatial variations in initial soil moisture obtained from the National Center for Environmental Predictions (NCEP) large-scale models are also introduced. Comparisons involving simulations over the southeastern United States for two different time periods, one during warmer, more humid summer conditions, and one during cooler, dryer winter conditions, reveals differences in surface conditions related to increases or decreases in near-surface atmospheric moisture con tent as a result of different soil properties. Three separate simulation types were considered. The base case assumed spatially homogeneous soil texture and initial soil moisture. The second case assumed variable soil texture and constant initial soil moisture, while the third case allowed for both variable soil texture and initial soil moisture. The simulation domain was further divided into four geographically distinct regions. It is concluded there is a more dramatic impact on thermodynamic variables (surface temperature and dewpoint) than on surface winds, and a more pronounced variability in results during the summer period. While no obvious trends in surface winds or dewpoint temperature were found relative to observations covering all regions and times, improvement in surface temperatures in most regions and time periods was generally seen with the incorporation of variable soil texture and initial soil moisture.

Buckley, R.

2001-06-27T23:59:59.000Z

213

Final Report - From Measurements to Models: Cross-Comparison of Measured and Simulated Behavioral States of the Atmosphere  

SciTech Connect (OSTI)

The ARM sites and the ARM Mobile Facility (AMF) were constructed to make measurements of the atmosphere and radiation system in order to quantify deficiencies in the simulation of clouds within models and to make improvements in those models. While the measurement infrastructure of ARM is well-developed and a model parameterization testbed capability has been established, additional effort is needed to develop statistical techniques which permit the comparison of simulation output from atmospheric models with actual measurements. Our project establishes a new methodology for objectively comparing ARM measurements to the outputs of leading global climate models and reanalysis data. The quantitative basis for this comparison is provided by a statistical procedure which establishes an exhaustive set of mutually-exclusive, recurring states of the atmosphere from sets of multivariate atmospheric and cloud conditions, and then classifies multivariate measurements or simulation outputs into those states. Whether measurements and models classify the atmosphere into the same states at specific locations through time provides an unequivocal comparison result. Times and locations in both geographic and state space of model-measurement agreement and disagreement will suggest directions for the collection of additional measurements at existing sites, provide insight into the global representativeness of the current ARM sites (suggesting locations and times for use of the AMF), and provide a basis for improvement of models. Two different analyses were conducted: One, using the Parallel Climate Model, focused on an IPCC climate change scenario and clusters that characterize long-term changes in the hydrologic cycle. The other, using the GISS Model E GCM and the ARM Active Remotely Sensed Cloud Layers product, explored current climate cloud regimes in the Tropical West Pacific.

Del Genio, Anthony D; Hoffman, Forrest M; Hargrove, Jr, William W

2007-10-22T23:59:59.000Z

214

A spectral transform dynamical core option within the Community Atmosphere Model (CAM4)  

SciTech Connect (OSTI)

A spectral transform dynamical core with an 85 spectral truncation resolution (T85) within the Community Atmosphere Model (CAM), version 4, is evaluated within the recently released Community Earth System Model, version 1.0 (CESM) global climate model. The spectral dynamical core option provides a well-known base within the climate model community from which to assess climate behavior and statistics, and its relative computational efficiency for smaller computing platforms allows it to be extended to perform climate length simulations using high-resolution configurations in the near term. To establish the characteristics of the CAM4 T85, an ensemble of simulations covering the present day observational period using forced sea surface temperatures and prescribed sea-ice extent are evaluated. Overall, the T85 ensemble attributes and biases are similar to a companion ensemble of simulations using the one degree finite volume (FV1) dynamical core, relative to observed and model derived datasets. Notable improvements with T85 compared to FV1 include the representation of wintertime Arctic sea level pressure and summer precipitation over the Western Indian subcontinent. The mean and spatial patterns of the land surface temperature trends over the AMIP period are generally well simulated with the T85 ensemble relative to observations, however the model is not able to capture the extent nor magnitude of changes in temperature extremes over the boreal summer, where the changes are most dramatic. Biases in the wintertime Arctic surface temperature and annual mean surface stress fields persist with T85 as with the CAM3 version of T85.

Evans, Katherine J [ORNL; Mahajan, Salil [ORNL; Branstetter, Marcia L [ORNL; McClean, Julie L. [Scripps Institute of Oceanography; Caron, Julie M. [National Center for Atmospheric Research (NCAR); Maltrud, Matthew E. [Los Alamos National Laboratory (LANL); Hack, James J [ORNL; Bader, David C [ORNL; Neale, Rich [National Center for Atmospheric Research (NCAR)

2014-01-01T23:59:59.000Z

215

The Carbon-Land Model Intercomparison Project (C-LAMP): A Model-Data Comparison System for Evaluation of Coupled Biosphere-Atmosphere Models  

SciTech Connect (OSTI)

The need to capture important climate feebacks in general circulation models (GCMs) has resulted in new efforts to include atmospheric chemistry and land and ocean biogeochemistry into the next generation of production climate models, now often referred to as Earth System Models (ESMs). While many terrestrial and ocean carbon models have been coupled to GCMs, recent work has shown that such models can yield a wide range of results, suggesting that a more rigorous set of offline and partially coupled experiments, along with detailed analyses of processes and comparisons with measurements, are warranted. The Carbon-Land Model Intercomparison Project (C-LAMP) provides a simulation protocol and model performance metrics based upon comparisons against best-available satellite- and ground-based measurements (Hoffman et al., 2007). C-LAMP provides feedback to the modeling community regarding model improvements and to the measurement community by suggesting new observational campaigns. C-LAMP Experiment 1 consists of a set of uncoupled simulations of terrestrial carbon models specifically designed to examine the ability of the models to reproduce surface carbon and energy fluxes at multiple sites and to exhibit the influence of climate variability, prescribed atmospheric carbon dioxide (CO{sub 2}), nitrogen (N) deposition, and land cover change on projections of terrestrial carbon fluxes during the 20th century. Experiment 2 consists of partially coupled simulations of the terrestrial carbon model with an active atmosphere model exchanging energy and moisture fluxes. In all experiments, atmospheric CO{sub 2} follows the prescribed historical trajectory from C{sup 4}MIP. In Experiment 2, the atmosphere model is forced with prescribed sea surface temperatures (SSTs) and corresponding sea ice concentrations from the Hadley Centre; prescribed CO{sub 2} is radiatively active; and land, fossil fuel, and ocean CO{sub 2} fluxes are advected by the model. Both sets of experiments have been performed using two different terrestrial biogeochemistry modules coupled to the Community Land Model version 3 (CLM3) in the Community Climate System Model version 3 (CCSM3): The CASA model of Fung, et al., and the carbon-nitrogen (CN) model of Thornton. Comparisons against Ameriflus site measurements, MODIS satellite observations, NOAA flask records, TRANSCOM inversions, and Free Air CO{sub 2} Enrichment (FACE) site measurements, and other datasets have been performed and are described in Randerson et al. (2009). The C-LAMP diagnostics package was used to validate improvements to CASA and CN for use in the next generation model, CLM4. It is hoped that this effort will serve as a prototype for an international carbon-cycle model benchmarking activity for models being used for the Inter-governmental Panel on Climate Change (IPCC) Fifth Assessment Report. More information about C-LAMP, the experimental protocol, performance metrics, output standards, and model-data comparisons from the CLM3-CASA and CLM3-CN models are available at http://www.climatemodeling.org/c-lamp.

Hoffman, Forrest M [ORNL; Randerson, Jim [University of California, Irvine; Thornton, Peter E [ORNL; Mahowald, Natalie [Cornell University; Bonan, Gordon [National Center for Atmospheric Research (NCAR); Running, Steven [University of Montana, Missoula; Fung, Inez [University of California, Berkeley

2009-01-01T23:59:59.000Z

216

Impact of Resolution on Simulation of Closed Mesoscale Cellular Convection Identified by Dynamically Guided Watershed Segmentation  

SciTech Connect (OSTI)

Organized mesoscale cellular convection (MCC) is a common feature of marine stratocumulus that forms in response to a balance between mesoscale dynamics and smaller scale processes such as cloud radiative cooling and microphysics. We use the Weather Research and Forecasting model with chemistry (WRF-Chem) and fully coupled cloud-aerosol interactions to simulate marine low clouds during the VOCALS-REx campaign over the southeast Pacific. A suite of experiments with 3- and 9-km grid spacing indicates resolution-dependent behavior. The simulations with finer grid spacing have smaller liquid water paths and cloud fractions, while cloud tops are higher. The observed diurnal cycle is reasonably well simulated. To isolate organized MCC characteristics we develop a new automated method, which uses a variation of the watershed segmentation technique that combines the detection of cloud boundaries with a test for coincident vertical velocity characteristics. This ensures that the detected cloud fields are dynamically consistent for closed MCC, the most common MCC type over the VOCALS-REx region. We demonstrate that the 3-km simulation is able to reproduce the scaling between horizontal cell size and boundary layer height seen in satellite observations. However, the 9-km simulation is unable to resolve smaller circulations corresponding to shallower boundary layers, instead producing invariant MCC horizontal scale for all simulated boundary layers depths. The results imply that climate models with grid spacing of roughly 3 km or smaller may be needed to properly simulate the MCC structure in the marine stratocumulus regions.

Martini, Matus; Gustafson, William I.; Yang, Qing; Xiao, Heng

2014-11-27T23:59:59.000Z

217

ATMOSPHERE AND SPECTRAL MODELS OF THE KEPLER-FIELD PLANETS HAT-P-7b AND TrES-2  

SciTech Connect (OSTI)

We develop atmosphere models of two of the three Kepler-field planets that were known prior to the start of the Kepler mission (HAT-P-7b and TrES-2). We find that published Kepler and Spitzer data for HAT-P-7b appear to require an extremely hot upper atmosphere on the dayside, with a strong thermal inversion and little day-night redistribution. The Spitzer data for TrES-2 suggest a mild thermal inversion with moderate day-night redistribution. We examine the effect of nonequilibrium chemistry on TrES-2 model atmospheres and find that methane levels must be adjusted by extreme amounts in order to cause even mild changes in atmospheric structure and emergent spectra. Our best-fit models to the Spitzer data for TrES-2 lead us to predict a low secondary eclipse planet-star flux ratio ({approx}<2 x 10{sup -5}) in the Kepler bandpass, which is consistent with what very recent observations have found. Finally, we consider how the Kepler-band optical flux from a hot exoplanet depends on the strength of a possible extra optical absorber in the upper atmosphere. We find that the optical flux is not monotonic in optical opacity, and the non-monotonicity is greater for brighter, hotter stars.

Spiegel, David S.; Burrows, Adam, E-mail: dsp@astro.princeton.ed, E-mail: burrows@astro.princeton.ed [Department of Astrophysical Sciences, Peyton Hall, Princeton University, Princeton, NJ 08544 (United States)

2010-10-10T23:59:59.000Z

218

Comparison of Atmospheric Water Vapor in Observational and Model Data Sets  

SciTech Connect (OSTI)

The global water vapor distribution for five observational based data sets and three GCM integrations are compared. The variables considered are the mean and standard deviation values of the precipitable water for the entire atmospheric column and the 500 to 300 hPa layer for January and July. The observationally based sets are the radiosonde data of Ross and Elliott, the ERA and NCEP reanalyses, and the NVAP blend of sonde and satellite data. The three GCM simulations all use the NCAR CCM3 as the atmospheric model. They include: a AMIP type simulation using observed SSTs for the period 1979 to 1993, the NCAR CSM 300 year coupled ocean--atmosphere integration, and a CSM integration with a 1% CO2 increase per year. The observational data exhibit some serious inconsistencies. There are geographical patterns of differences related to interannual variations and national instrument biases. It is clear that the proper characterization of water vapor is somewhat uncertain. Some conclusions about these data appear to be robust even given the discrepancies. The ERA data are too dry especially in the upper levels. The observational data evince much better agreement in the data rich Northern Hemisphere compared to the Southern. Distinct biases are quite pronounced over the Southern Ocean. The mean values and particularly the standard deviations of the three reanalyses are very dependent upon the GCM used as the assimilation vehicle for the analyses. This is made clear by the much enhanced tropical variability in the NCEP/DOE/ AMIP reanalyses compared the initial NCEP/NCAR Reanalysis. The NCAR CCM3 shows consistent evidence of a dry bias. The 1% CO2 experiment shows a very similar pattern of disagreement with the sonde data as the other integrations, once account is taken of the warming trend. No new modes of difference are evident in the 1% CO2 experiment. All the CCM3 runs indicated too much Tropical variability especially in the western Tropical Pacific and Southeast Asia. A EOF analysis of the interannual variations of the zonally averaged precipitable water and the 500 to 300 hPa layer reveals fundamental differences in the structure of the variations. The impact of ENSO and variations of the ITCZ have only a low level of correspondence between the observed data, much less the simulations. It is apparent that an adequate characterization of the climatology of the global water vapor distribution is not yet at hand.

Boyle, J.S.

2000-03-01T23:59:59.000Z

219

Crossing the mesoscale no-mans land via parallel kinetic Monte Carlo.  

SciTech Connect (OSTI)

The kinetic Monte Carlo method and its variants are powerful tools for modeling materials at the mesoscale, meaning at length and time scales in between the atomic and continuum. We have completed a 3 year LDRD project with the goal of developing a parallel kinetic Monte Carlo capability and applying it to materials modeling problems of interest to Sandia. In this report we give an overview of the methods and algorithms developed, and describe our new open-source code called SPPARKS, for Stochastic Parallel PARticle Kinetic Simulator. We also highlight the development of several Monte Carlo models in SPPARKS for specific materials modeling applications, including grain growth, bubble formation, diffusion in nanoporous materials, defect formation in erbium hydrides, and surface growth and evolution.

Garcia Cardona, Cristina (San Diego State University); Webb, Edmund Blackburn, III; Wagner, Gregory John; Tikare, Veena; Holm, Elizabeth Ann; Plimpton, Steven James; Thompson, Aidan Patrick; Slepoy, Alexander (U. S. Department of Energy, NNSA); Zhou, Xiao Wang; Battaile, Corbett Chandler; Chandross, Michael Evan

2009-10-01T23:59:59.000Z

220

SUPERBURST MODELS FOR NEUTRON STARS WITH HYDROGEN- AND HELIUM-RICH ATMOSPHERES  

SciTech Connect (OSTI)

Superbursts are rare day-long type I X-ray bursts due to carbon flashes on accreting neutron stars in low-mass X-ray binaries. They heat the neutron star envelope such that the burning of accreted hydrogen and helium becomes stable, and the common shorter X-ray bursts are quenched. Short bursts reappear only after the envelope cools down. We study multi-zone one-dimensional models of the neutron star envelope, in which we follow carbon burning during the superburst, and we include hydrogen and helium burning in the atmosphere above. We investigate the cases of both a solar-composition and a helium-rich atmosphere. This allows us to study for the first time a wide variety of thermonuclear burning behavior as well as the transitions between the different regimes in a self-consistent manner. For solar composition, burst quenching ends much sooner than previously expected. This is because of the complex interplay between the 3{alpha}, hot CNO, and CNO breakout reactions. Stable burning of hydrogen and helium transitions via marginally stable burning (mHz quasi-periodic oscillations) to less energetic bursts with short recurrence times. We find a short-lived bursting mode where weaker and stronger bursts alternate. Eventually the bursting behavior changes back to that of the pre-superburst bursts. Because of the scarcity of observations, this transition has not been directly detected after a superburst. Using the MINBAR burst catalog we identify the shortest upper limit on the quenching time for 4U 1636-536, and derive further constraints on the timescale on which bursts return.

Keek, L. [National Superconducting Cyclotron Laboratory, Department of Physics and Astronomy, and Joint Institute for Nuclear Astrophysics, Michigan State University, East Lansing, MI 48824 (United States); Heger, A. [School of Physics and Astronomy, University of Minnesota, 116 Church Street SE, Minneapolis, MN 55455 (United States); In 't Zand, J. J. M., E-mail: keek@nscl.msu.edu [SRON Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht (Netherlands)

2012-06-20T23:59:59.000Z

Note: This page contains sample records for the topic "atmospheric mesoscale model" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Low-frequency variability and heat transport in a low-order nonlinear coupled ocean-atmosphere model  

E-Print Network [OSTI]

We formulate and study a low-order nonlinear coupled ocean-atmosphere model with an emphasis on the impact of radiative and heat fluxes and of the frictional coupling between the two components. This model version extends a previous 24-variable version by adding a dynamical equation for the passive advection of temperature in the ocean, together with an energy balance model. The bifurcation analysis and the numerical integration of the model reveal the presence of low-frequency variability (LFV) concentrated on and near a long-periodic, attracting orbit. This orbit combines atmospheric and oceanic modes, and it arises for large values of the meridional gradient of radiative input and of frictional coupling. Chaotic behavior develops around this orbit as it loses its stability; this behavior is still dominated by the LFV on decadal and multi-decadal time scales that is typical of oceanic processes. Atmospheric diagnostics also reveals the presence of predominant low- and high-pressure zones, as well as of a subtropical jet; these features recall realistic climatological properties of the oceanic atmosphere. Finally, a predictability analysis is performed. Once the decadal-scale periodic orbits develop, the coupled system's short-term instabilities --- as measured by its Lyapunov exponents --- are drastically reduced, indicating the ocean's stabilizing role on the atmospheric dynamics. On decadal time scales, the recurrence of the solution in a certain region of the invariant subspace associated with slow modes displays some extended predictability, as reflected by the oscillatory behavior of the error for the atmospheric variables at long lead times.

Stphane Vannitsem; Jonathan Demaeyer; Lesley De Cruz; Michael Ghil

2014-12-01T23:59:59.000Z

222

A model study of the impact of magnetic field structure on atmospheric composition during solar proton events  

E-Print Network [OSTI]

A model study of the impact of magnetic field structure on atmospheric composition during solar is possible into regions that are at the moment effectively shielded by the Earth's magnetic field. A two (process, timescale, magnetostratigraphy); 1650 Global Change: Solar variability; 2716 Magnetospheric

Steinhoff, Heinz-Jürgen

223

A Sensitivity Study of Radiative Fluxes at the Top of Atmosphere to Cloud-Microphysics and Aerosol Parameters in the Community Atmosphere Model CAM5  

SciTech Connect (OSTI)

In this study, we investigated the sensitivity of net radiative fluxes (FNET) at the top of atmosphere (TOA) to 16 selected uncertain parameters mainly related to the cloud microphysics and aerosol schemes in the Community Atmosphere Model version 5 (CAM5). We adopted a quasi-Monte Carlo (QMC) sampling approach to effectively explore the high dimensional parameter space. The output response variables (e.g., FNET) were simulated using CAM5 for each parameter set, and then evaluated using generalized linear model analysis. In response to the perturbations of these 16 parameters, the CAM5-simulated global annual mean FNET ranges from -9.8 to 3.5 W m-2 compared to the CAM5-simulated FNET of 1.9 W m-2 with the default parameter values. Variance-based sensitivity analysis was conducted to show the relative contributions of individual parameter perturbation to the global FNET variance. The results indicate that the changes in the global mean FNET are dominated by those of cloud forcing (CF) within the parameter ranges being investigated. The size threshold parameter related to auto-conversion of cloud ice to snow is confirmed as one of the most influential parameters for FNET in the CAM5 simulation. The strong heterogeneous geographic distribution of FNET variation shows parameters have a clear localized effect over regions where they are acting. However, some parameters also have non-local impacts on FNET variance. Although external factors, such as perturbations of anthropogenic and natural emissions, largely affect FNET variations at the regional scale, their impact is weaker than that of model internal parameters in terms of simulating global mean FNET in this study. The interactions among the 16 selected parameters contribute a relatively small portion of the total FNET variations over most regions of the globe. This study helps us better understand the CAM5 model behavior associated with parameter uncertainties, which will aid the next step of reducing model uncertainty via calibration of uncertain model parameters with the largest sensitivity.

Zhao, Chun; Liu, Xiaohong; Qian, Yun; Yoon, Jin-Ho; Hou, Zhangshuan; Lin, Guang; McFarlane, Sally A.; Wang, Hailong; Yang, Ben; Ma, Po-Lun; Yan, Huiping; Bao, Jie

2013-11-08T23:59:59.000Z

224

Convective cell development and propagation in a mesoscale convective complex  

E-Print Network [OSTI]

~ , National Fisheries University of Pusan Chairman of Advisory Committee: Dr ~ Kennth CD Brundidge A case study was made of the mesoscale convective complex (MCC) which occurred over southern Oklahoma and northern Texas on 27 May 1981. This storm moved... in an east-southeasterly direction and during much of its lifetime was observable by radars at Oklahoma City, OK and Stephenville, TX. It was found that the direction of cell (VIP level 3 or more reflectivity) propagation was somewhat erratic...

Ahn, Yoo-Shin

2012-06-07T23:59:59.000Z

225

A new model of cosmogenic production of radiocarbon 14 C in the atmosphere  

E-Print Network [OSTI]

of primary cosmic ray particles ranging from 0.1 to 1000 GeV/nucleon. We have calculated the global in the atmosphere by the primary cosmic rays of the given type with the fixed energy and unit intensity outside the atmosphere), which can be convoluted with any given energy spectrum of the primary cosmic rays (e.g., Webber

Usoskin, Ilya G.

226

Scientific Final Report: COLLABORATIVE RESEARCH: CONTINUOUS DYNAMIC GRID ADAPTATION IN A GLOBAL ATMOSPHERIC MODEL: APPLICATION AND REFINEMENT  

SciTech Connect (OSTI)

This project had goals of advancing the performance capabilities of the numerical general circulation model EULAG and using it to produce a fully operational atmospheric global climate model (AGCM) that can employ either static or dynamic grid stretching for targeted phenomena. The resulting AGCM combined EULAG's advanced dynamics core with the 'physics' of the NCAR Community Atmospheric Model (CAM). Effort discussed below shows how we improved model performance and tested both EULAG and the coupled CAM-EULAG in several ways to demonstrate the grid stretching and ability to simulate very well a wide range of scales, that is, multi-scale capability. We leveraged our effort through interaction with an international EULAG community that has collectively developed new features and applications of EULAG, which we exploited for our own work summarized here. Overall, the work contributed to over 40 peer-reviewed publications and over 70 conference/workshop/seminar presentations, many of them invited.

William J. Gutowski; Joseph M. Prusa, Piotr K. Smolarkiewicz

2012-04-09T23:59:59.000Z

227

DUSTRAN 1.0 Users Guide: A GIS-Based Atmospheric Dust Dispersion Modeling System  

SciTech Connect (OSTI)

The U.S. Department of Energys Pacific Northwest National Laboratory just completed a multi-year project to develop a fully tested and documented atmospheric dispersion modeling system (DUST TRANsport or DUSTRAN) to assist the U.S. Department of Defense in addressing particulate air quality issues at military training and testing ranges. This manual documents the DUSTRAN modeling system and includes installation instructions, a users guide, and detailed example tutorials.

Allwine, K Jerry; Rutz, Frederick C.; Shaw, William J.; Rishel, Jeremy P.; Fritz, Brad G.; Chapman, Elaine G.; Hoopes, Bonnie L.; Seiple, Timothy E.

2006-09-22T23:59:59.000Z

228

Improved HCN/HNC linelist, model atmospheres and synthetic spectra for WZ Cas  

E-Print Network [OSTI]

We build an accurate database of 5200 HCN and HNC rotation-vibration energy levels, determined from existing laboratory data. 20~000 energy levels in the Harris et al. (2002) linelist are assigned approximate quantum numbers. These assignments, lab determined energy levels and Harris et al (2002) energy levels are incorporated in to a new energy level list. A new linelist is presented, in which frequencies are computed using the lab determined energy levels where available, and the ab initio energy levels otherwise. The new linelist is then used to compute new model atmospheres and synthetic spectra for the carbon star WZ Cas. This results in better fit to the spectrum of WZ Cas in which the absorption feature at 3.56 micron is reproduced to a higher degree of accuracy than has previously been possible. We improve the reproduction of HCN absorption features by reducing the abundance of Si to [Si/H] = --0.5 dex, however, the strengths of the $\\Delta v=2$ CS band heads are over-predicted.

G. J. Harris; J. Tennyson; B. M. Kaminsky; Ya. V. Pavlenko; H. R. A. Jones

2005-12-14T23:59:59.000Z

229

E-Print Network 3.0 - approximate mesoscale information Sample...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

of Technology Collection: Engineering 5 Mesoscale variability in time series data: Satellite-based estimates for the U.S. JGOFS Bermuda Atlantic Summary: coverage. GLOVER ET...

230

Atmospheric Pollution Research 1 (2010) 220228 Atmospheric Pollution Research  

E-Print Network [OSTI]

Atmospheric Pollution Research 1 (2010) 220228 Atmospheric Pollution Research www in modeling of the associated multiphase processes. Iron redox species are important pollutants. The oxidative capacity of the atmospheric cloud water decreases when dissolution is included

Boyer, Edmond

231

he Impact of Primary Marine Aerosol on Atmospheric Chemistry, Radiation and Climate: A CCSM Model Development Study  

SciTech Connect (OSTI)

This project examined the potential large-scale influence of marine aerosol cycling on atmospheric chemistry, physics and radiative transfer. Measurements indicate that the size-dependent generation of marine aerosols by wind waves at the ocean surface and the subsequent production and cycling of halogen-radicals are important but poorly constrained processes that influence climate regionally and globally. A reliable capacity to examine the role of marine aerosol in the global-scale atmospheric system requires that the important size-resolved chemical processes be treated explicitly. But the treatment of multiphase chemistry across the breadth of chemical scenarios encountered throughout the atmosphere is sensitive to the initial conditions and the precision of the solution method. This study examined this sensitivity, constrained it using high-resolution laboratory and field measurements, and deployed it in a coupled chemical-microphysical 3-D atmosphere model. First, laboratory measurements of fresh, unreacted marine aerosol were used to formulate a sea-state based marine aerosol source parameterization that captured the initial organic, inorganic, and physical conditions of the aerosol population. Second, a multiphase chemical mechanism, solved using the Max Planck Institute for Chemistry??s MECCA (Module Efficiently Calculating the Chemistry of the Atmosphere) system, was benchmarked across a broad set of observed chemical and physical conditions in the marine atmosphere. Using these results, the mechanism was systematically reduced to maximize computational speed. Finally, the mechanism was coupled to the 3-mode modal aerosol version of the NCAR Community Atmosphere Model (CAM v3.6.33). Decadal-scale simulations with CAM v.3.6.33, were run both with and without reactive-halogen chemistry and with and without explicit treatment of particulate organic carbon in the marine aerosol source function. Simulated results were interpreted (1) to evaluate influences of marine aerosol production on the microphysical properties of aerosol populations and clouds over the ocean and the corresponding direct and indirect effects on radiative transfer; (2) atmospheric burdens of reactive halogen species and their impacts on O3, NOx, OH, DMS, and particulate non-sea-salt SO42-; and (3) the global production and influences of marine-derived particulate organic carbon. The model reproduced major characteristics of the marine aerosol system and demonstrated the potential sensitivity of global, decadal-scale climate metrics to multiphase marine-derived components of Earth??s troposphere. Due to the combined computational burden of the coupled system, the currently available computational resources were the limiting factor preventing the adequate statistical analysis of the overall impact that multiphase chemistry might have on climate-scale radiative transfer and climate.

Keene, William C. [University of Virginia] [University of Virginia; Long, Michael S. [University of Virginia] [University of Virginia

2013-05-20T23:59:59.000Z

232

Vortex arrays and meso-scale turbulence of self-propelled particles  

E-Print Network [OSTI]

Inspired by the Turing mechanism for pattern formation, we propose a simple self-propelled particle model with short-ranged alignment and anti-alignment at larger distances. It is able to produce orientationally ordered states, periodic vortex patterns as well as meso-scale turbulence. The latter phase resembles observations in dense bacterial suspensions. The model allows a systematic derivation and analysis of a kinetic theory as well as hydrodynamic equations for density and momentum fields. A phase diagram with regions of such pattern formation as well as spatially homogeneous orientational order and disorder is obtained from a linear stability analysis of these continuum equations. Microscopic Langevin simulations of the self-propelled particle system are in agreement with these findings.

Robert Grossmann; Pawel Romanczuk; Markus Br; Lutz Schimansky-Geier

2014-05-30T23:59:59.000Z

233

Atmospheric Model Ocean Model  

E-Print Network [OSTI]

-Seasonal Prediction of Remote Drivers of Australian Climate Variability using POAMA Andrew G Marshall, Debbie Hudson index at 140°°°°E for OBS and POAMA hindcasts > http://poama.bom.gov.au andrew.marshall@bom.gov.au #12;

Marshall, Andrew

234

On the Sensitivity of Atmospheric Model Implied Ocean Heat Transport to the Dominant Terms of the Surface Energy Balance  

SciTech Connect (OSTI)

The oceanic meridional heat transport (T{sub o}) implied by an atmospheric General Circulation Model (GCM) can help evaluate a model's readiness for coupling with an ocean GCM. In this study we examine the T{sub o} from benchmark experiments of the Atmospheric Model Intercomparison Project, and evaluate the sensitivity of T{sub o} to the dominant terms of the surface energy balance. The implied global ocean TO in the Southern Hemisphere of many models is equatorward, contrary to most observationally-based estimates. By constructing a hybrid (model corrected by observations) T{sub o}, an earlier study demonstrated that the implied heat transport is critically sensitive to the simulated shortwave cloud radiative effects, which have been argued to be principally responsible for the Southern Hemisphere problem. Systematic evaluation of one model in a later study suggested that the implied T{sub o} could be equally as sensitive to a model's ocean surface latent heat flux. In this study we revisit the problem with more recent simulations, making use of estimates of ocean surface fluxes to construct two additional hybrid calculations. The results of the present study demonstrate that indeed the implied T{sub o} of an atmospheric model is very sensitive to problems in not only the surface net shortwave, but the latent heat flux as well. Many models underestimate the shortwave radiation reaching the surface in the low latitudes, and overestimate the latent heat flux in the same region. The additional hybrid transport calculations introduced here could become useful model diagnostic tests as estimates of implied ocean surface fluxes are improved.

Gleckler, P J

2004-11-03T23:59:59.000Z

235

Atmospheric Carbon Dioxide Variability in the Community Earth System Model: Evaluation and Transient Dynamics during the Twentieth and Twenty-First Centuries  

E-Print Network [OSTI]

Atmospheric Carbon Dioxide Variability in the Community Earth System Model: Evaluation pathways (RCPs 4.5 and 8.5) using the Community Earth System Model­Biogeochemistry (CESM1- BGC). CO2

Hoffman, Forrest M.

236

The solar photospheric abundance of hafnium and thorium. Results from CO5BOLD 3D hydrodynamic model atmospheres  

E-Print Network [OSTI]

Context: The stable element hafnium (Hf) and the radioactive element thorium (Th) were recently suggested as a suitable pair for radioactive dating of stars. The applicability of this elemental pair needs to be established for stellar spectroscopy. Aims: We aim at a spectroscopic determination of the abundance of Hf and Th in the solar photosphere based on a \\cobold 3D hydrodynamical model atmosphere. We put this into a wider context by investigating 3D abundance corrections for a set of G- and F-type dwarfs. Method: High-resolution, high signal-to-noise solar spectra were compared to line synthesis calculations performed on a solar CO5BOLD model. For the other atmospheres, we compared synthetic spectra of CO5BOLD 3D and associated 1D models. Results: For Hf we find a photospheric abundance A(Hf)=0.87+-0.04, in good agreement with a previous analysis, based on 1D model atmospheres. The weak Th ii 401.9 nm line constitutes the only Th abundance indicator available in the solar spectrum. It lies in the red wing of an Ni-Fe blend exhibiting a non-negligible convective asymmetry. Accounting for the asymmetry-related additional absorption, we obtain A(Th)=0.09+-0.03, consistent with the meteoritic abundance, and about 0.1 dex lower than obtained in previous photospheric abundance determinations. Conclusions: Only for the second time, to our knowledge, has am non-negligible effect of convective line asymmetries on an abundance derivation been highlighted. Three-dimensional hydrodynamical simulations should be employed to measure Th abundances in dwarfs if similar blending is present, as in the solar case. In contrast, 3D effects on Hf abundances are small in G- to mid F-type dwarfs and sub-giants, and 1D model atmospheres can be conveniently used.

Elisabetta Caffau; L. Sbordone; H. -G. Ludwig; P. Bonifacio; M. Steffen; N. T. Behara

2008-03-25T23:59:59.000Z

237

Carbon-nitrogen interactions regulate climate-carbon cycle feedbacks: results from an atmosphere-ocean general circulation model  

E-Print Network [OSTI]

forests indi- cates that the model representation of competition between plants and microbes for new mineral nitrogen resources is reasonable. Our results suggest a weaker dependence of net land carbon flux on soil moisture changes in tropical regions... National Laboratory, Oak Ridge, TN 37831-6335, USA 2Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA 02543-1543, USA 3Climate and Global Dynamics Division, National Center for Atmospheric Research...

Thornton, P. E.; Doney, S. C.; Lindsay, Keith; Moore, J. K.; Mahowald, N. M.; Randerson, J. T.; Fung, I.; Lamarque, J. F.; Feddema, Johannes J.

2009-01-01T23:59:59.000Z

238

Benchmark experiments with global climate models applicable to extra-solar gas giant planets in the shallow atmosphere approximation  

E-Print Network [OSTI]

The growing field of exoplanetary atmospheric modelling has seen little work on standardised benchmark tests for its models, limiting understanding of the dependence of results on specific models and conditions. With spatially resolved observations as yet difficult to obtain, such a test is invaluable. Although an intercomparison test for models of tidally locked gas giant planets has previously been suggested and carried out, the data provided were limited in terms of comparability. Here, the shallow PUMA model is subjected to such a test, and detailed statistics produced to facilitate comparison, with both time means and the associated standard deviations displayed, removing the time dependence and providing a measure of the variability. Model runs have been analysed to determine the variability between resolutions, and the effect of resolution on the energy spectra studied. Superrotation is a robust and reproducible feature at all resolutions.

Bending, V L; Kolb, U

2012-01-01T23:59:59.000Z

239

Mesoscale Self-Assembly of Hexagonal Plates Using Lateral Capillary Forces: Synthesis Using the "Capillary Bond"  

E-Print Network [OSTI]

Mesoscale Self-Assembly of Hexagonal Plates Using Lateral Capillary Forces: Synthesis Using examines self-assembly in a quasi-two-dimensional, mesoscale system. The system studied here involves and hydrophilic faces on the hexagonal plates led to three outcomes: (i) the extension of the strategies of self-assembly

Prentiss, Mara

240

Generation of strong mesoscale eddies by weak ocean gyres by Michael A. Spall1  

E-Print Network [OSTI]

Generation of strong mesoscale eddies by weak ocean gyres by Michael A. Spall1 ABSTRACT The generation of strong mesoscale variability through instability of the large-scale circulation in the interior of oceanic gyres is addressed. While previous studies have shown that eddies generated from weakly sheared

Note: This page contains sample records for the topic "atmospheric mesoscale model" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Estimates of Radioxenon Released from Southern Hemisphere Medical isotope Production Facilities Using Measured Air Concentrations and Atmospheric Transport Modeling  

SciTech Connect (OSTI)

Abstract The International Monitoring System (IMS) of the Comprehensive-Nuclear-Test-Ban-Treaty monitors the atmosphere for radioactive xenon leaking from underground nuclear explosions. Emissions from medical isotope production represent a challenging background signal when determining whether measured radioxenon in the atmosphere is associated with a nuclear explosion prohibited by the treaty. The Australian Nuclear Science and Technology Organisation (ANSTO) operates a reactor and medical isotope production facility in Lucas Heights, Australia. This study uses two years of release data from the ANSTO medical isotope production facility and Xe-133 data from three IMS sampling locations to estimate the annual releases of Xe-133 from medical isotope production facilities in Argentina, South Africa, and Indonesia. Atmospheric dilution factors derived from a global atmospheric transport model were used in an optimization scheme to estimate annual release values by facility. The annual releases of about 6.81014 Bq from the ANSTO medical isotope production facility are in good agreement with the sampled concentrations at these three IMS sampling locations. Annual release estimates for the facility in South Africa vary from 1.21016 to 2.51016 Bq and estimates for the facility in Indonesia vary from 6.11013 to 3.61014 Bq. Although some releases from the facility in Argentina may reach these IMS sampling locations, the solution to the objective function is insensitive to the magnitude of those releases.

Eslinger, Paul W.; Friese, Judah I.; Lowrey, Justin D.; McIntyre, Justin I.; Miley, Harry S.; Schrom, Brian T.

2014-04-06T23:59:59.000Z

242

Customizing mesoscale self-assembly with 3D printing  

E-Print Network [OSTI]

Self-assembly due to capillary forces is a common method for generating 2D mesoscale structures from identical floating particles at the liquid-air interface. Designing building blocks to obtain a desired mesoscopic structure is a scientific challenge. We show herein that it is possible to shape the particles with a low cost 3D printer, for composing specific mesoscopic structures. Our method is based on the creation of capillary multipoles inducing either attractive or repulsive forces. Since capillary interactions can be downscaled, our method opens new ways to low cost microfabrication.

M. Poty; G. Lumay; N. Vandewalle

2013-10-17T23:59:59.000Z

243

Deterministic, Nanoscale Fabrication of Mesoscale Objects  

SciTech Connect (OSTI)

Neither LLNL nor any other organization has the capability to perform deterministic fabrication of mm-sized objects with arbitrary, {micro}m-sized, 3-dimensional features with 20-nm-scale accuracy and smoothness. This is particularly true for materials such as high explosives and low-density aerogels. For deterministic fabrication of high energy-density physics (HEDP) targets, it will be necessary both to fabricate features in a wide variety of materials as well as to understand and simulate the fabrication process. We continue to investigate, both in experiment and in modeling, the ablation/surface-modification processes that occur with the use of laser pulses that are near the ablation threshold fluence. During the first two years, we studied ablation of metals, and we used sub-ps laser pulses, because pulses shorter than the electron-phonon relaxation time offered the most precise control of the energy that can be deposited into a metal surface. The use of sub-ps laser pulses also allowed a decoupling of the energy-deposition process from the ensuing movement/ablation of the atoms from the solid, which simplified the modeling. We investigated the ablation of material from copper, gold, and nickel substrates. We combined the power of the 1-D hydrocode ''HYADES'' with the state-of-the-art, 3-D molecular dynamics simulations ''MDCASK'' in our studies. For FY04, we have stretched ourselves to investigate laser ablation of carbon, including chemically-assisted processes. We undertook this research, because the energy deposition that is required to perform direct sublimation of carbon is much higher than that to stimulate the reaction 2C + O{sub 2} => 2CO. Thus, extremely fragile carbon aerogels might survive the chemically-assisted process more readily than ablation via direct laser sublimation. We had planned to start by studying vitreous carbon and move onto carbon aerogels. We were able to obtain flat, high-quality vitreous carbon, which was easy to work on, experimentally and relatively easy to model. We were provided with bulk samples of carbon aerogel by Dr. Joe Satcher, but the shop that would have prepared mounted samples for us was overwhelmed by programmatic assignments. We are pursuing aligned carbon nanotubes, provided to us by colleagues at NASA Ames Research Center, as an alternative to aerogels. Dr. Gilmer started modeling the laser/thermally accelerated reactions of carbon with H{sub 2}, rather than O{sub 2}, due to limited information on equation of state for CO. We have extended our molecular dynamics models of ablation to include carbon in the form of graphite, vitreous carbon, and aerogels. The computer code has features that allow control of temperature, absorption of shock waves, and for the ejection of material from the computational cell. We form vitreous carbon atomic configurations by melting graphite in a microcanonical cell at a temperature of about 5000K. Quenching the molten carbon at a controlled rate of cooling yields material with a structure close to that of the vitreous carbon produced in the laboratory. To represent the aerogel, we have a computer code that connects ''graphite'' rods to randomly placed points in the 3-D computational cell. Ablation simulations yield results for vitreous carbon similar to our previous results with copper, usually involving the transient melting of the material above the threshold energy density. However, some fracturing in the solid regions occurs in this case, but was never observed in copper. These simulations are continuing, together with studies of the reaction of hydrogen with vitreous graphite at high temperatures. These reactions are qualitatively similar to that of oxygen with the carbon atoms at the surface, and the simulations should provide insight into the applicability of the use of chemical reactions to shape the surfaces of aerogels.

Jr., R M; Shirk, M; Gilmer, G; Rubenchik, A

2004-09-24T23:59:59.000Z

244

The Tropical Atmospheric El Nio Signal in Satellite Precipitation Data and a Global Climate Model  

E-Print Network [OSTI]

) ABSTRACT Aspects of the tropical atmospheric response to El Niño related to the global energy and water and the Advanced Micro- wave Scanning Radiometer-E and simulations from the Goddard Institute for Space Studies are highly correlated, but anomalies in stratiform­convective rainfall partitioning in the two datasets

245

Causes and implications of persistent atmospheric carbon dioxide biases in Earth System Models  

E-Print Network [OSTI]

2013), The Community Earth System Model: A framework forsimu- lations from 15 Earth System Models (ESMs) Most ESMsdioxide biases in Earth System Models, J. Geophys. Res.

2014-01-01T23:59:59.000Z

246

OUMBE, Armel, WALD, Lucien, BLANC, Philippe, and SCHROEDTER-HOMSCHEIDT, Marion. Exploitation of radiative transfer model for assessing solar radiation: the relative importance of atmospheric  

E-Print Network [OSTI]

of radiative transfer model for assessing solar radiation: the relative importance of atmospheric constituents, Germany * Corresponding Author, armel.oumbe@ensmp.fr Abstract Solar radiation is modified in its way: solar radiation, atmospheric optics, satellite images, Heliosat method 1. Introduction A wealth

Paris-Sud XI, Université de

247

Development of an atmospheric aerosol model for studies of global budgets and effects of airborne particulate material  

SciTech Connect (OSTI)

A microphysics-removal Atmospheric Aerosol Model (AAM) is developed for use in General Circulation Models (GCM) to study global budgets and effects of particulate material. In this model the particle population is assumed to be composed of a set of log-normal modes whose time evolution due to microphysical processes is described via prognostic equations for an appropriate number of moments of the particle size distribution. This newly devised technique, by making use of a small number of prognostic equations for the aerosol variables and utilizing optimized numerical procedures, renders the model computationally efficient, hence particularly suitable for use in complex 3D GCMs. Detailed parameterizations of particle coagulation, sedimentation, dry deposition, and wet removal are incorporated into the AAM.

Giorgi, F.

1986-01-01T23:59:59.000Z

248

Analysis of Mesoscale Model Data for Wind Integration (Poster)  

SciTech Connect (OSTI)

Supports examination of implications of national 20% wind vision, and provides input to integration and transmission studies for operational impact of large penetrations of wind on the grid.

Schwartz, M.; Elliott, D.; Lew, D.; Corbus, D.; Scott, G.; Haymes, S.; Wan, Y. H.

2009-05-01T23:59:59.000Z

249

AN URBAN SURFACE EXCHANGE PARAMETERISATION FOR MESOSCALE MODELS  

E-Print Network [OSTI]

boundary layer, Urban climato- logy, Urban energy balance. 1. Introduction The main reason floor) and vertical (walls) surfaces on the wind speed, temperature and turbulent kinetic energy in a bidimensional case of a city over flat terrain. The new parameterisation is shown to be able to reproduce

250

An analytical coarse-graining method which preserves the free energy, structural correlations, and thermodynamic state of polymer melts from the atomistic to the mesoscale  

E-Print Network [OSTI]

Structural and thermodynamic consistency of coarse-graining models across multiple length scales is essential for the predictive role of multi-scale modeling and molecular dynamic simulations that use mesoscale descriptions. Our approach is a coarse-grained model based on integral equation theory, which can represent polymer chains at variable levels of chemical details. The model is analytical and depends on molecular and thermodynamic parameters of the system under study, as well as on the direct correlation function in the k --> 0 limit, c0. A numerical solution to the PRISM integral equations is used to determine c0, by adjusting the value of the effective hard sphere diameter, d, to agree with the predicted equation of state. This single quantity parameterizes the coarse-grained potential, which is used to perform mesoscale simulations that are directly compared with atomistic-level simulations of the same system. We test our coarse-graining formalism by comparing structural correlations, isothermal compressibility, equation of state, Helmholtz and Gibbs free energies, and potential energy and entropy using both united atom and coarse-grained descriptions. We find quantitative agreement between the analytical formalism for the thermodynamic properties, and the results of Molecular Dynamics simulations, independent of the chosen level of representation. In the mesoscale description, the potential energy of the soft-particle interaction becomes a free energy in the coarse-grained coordinates which preserves the excess free energy from an ideal gas across all levels of description. The structural consistency between the united-atom and mesoscale descriptions means the relative entropy between descriptions has been minimized without any variational optimization parameters. The approach is general and applicable to any polymeric system in different thermodynamic conditions.

J. McCarty; A. J. Clark; J. Copperman; M. G. Guenza

2014-07-03T23:59:59.000Z

251

An analytical coarse-graining method which preserves the free energy, structural correlations, and thermodynamic state of polymer melts from the atomistic to the mesoscale  

SciTech Connect (OSTI)

Structural and thermodynamic consistency of coarse-graining models across multiple length scales is essential for the predictive role of multi-scale modeling and molecular dynamic simulations that use mesoscale descriptions. Our approach is a coarse-grained model based on integral equation theory, which can represent polymer chains at variable levels of chemical details. The model is analytical and depends on molecular and thermodynamic parameters of the system under study, as well as on the direct correlation function in the k ? 0 limit, c{sub 0}. A numerical solution to the PRISM integral equations is used to determine c{sub 0}, by adjusting the value of the effective hard sphere diameter, d{sub HS}, to agree with the predicted equation of state. This single quantity parameterizes the coarse-grained potential, which is used to perform mesoscale simulations that are directly compared with atomistic-level simulations of the same system. We test our coarse-graining formalism by comparing structural correlations, isothermal compressibility, equation of state, Helmholtz and Gibbs free energies, and potential energy and entropy using both united atom and coarse-grained descriptions. We find quantitative agreement between the analytical formalism for the thermodynamic properties, and the results of Molecular Dynamics simulations, independent of the chosen level of representation. In the mesoscale description, the potential energy of the soft-particle interaction becomes a free energy in the coarse-grained coordinates which preserves the excess free energy from an ideal gas across all levels of description. The structural consistency between the united-atom and mesoscale descriptions means the relative entropy between descriptions has been minimized without any variational optimization parameters. The approach is general and applicable to any polymeric system in different thermodynamic conditions.

McCarty, J.; Clark, A. J.; Copperman, J.; Guenza, M. G., E-mail: mguenza@uoregon.edu [Department of Chemistry and Biochemistry, and Institute of Theoretical Science, University of Oregon, Eugene, Oregon 97403 (United States)

2014-05-28T23:59:59.000Z

252

TransCom N[subscript 2]O model inter-comparison Part 2: Atmospheric inversion estimates of N[subscript 2]O emissions  

E-Print Network [OSTI]

This study examines N[subscript 2]O emission estimates from five different atmospheric inversion frameworks based on chemistry transport models (CTMs). The five frameworks differ in the choice of CTM, meteorological data, ...

Thompson, R. L.

253

Modelled Black Carbon Radiative Forcing and Atmospheric Lifetime in AeroCom Phase II Constrained by Aircraft Observations  

SciTech Connect (OSTI)

Black carbon (BC) aerosols absorb solar radiation, and are generally held to exacerbate global warming through exerting a positive radiative forcing1. However, the total contribution of BC to the ongoing changes in global climate is presently under debate2-8. Both anthropogenic BC emissions and the resulting spatial and temporal distribution of BC concentration are highly uncertain2,9. In particular, long range transport and processes affecting BC atmospheric lifetime are poorly understood, leading to large estimated uncertainty in BC concentration at high altitudes and far from emission sources10. These uncertainties limit our ability to quantify both the historical, present and future anthropogenic climate impact of BC. Here we compare vertical profiles of BC concentration from four recent aircraft measurement campaigns with 13 state of the art aerosol models, and show that recent assessments may have overestimated present day BC radiative forcing. Further, an atmospheric lifetime of BC of less than 5 days is shown to be essential for reproducing observations in transport dominated remote regions. Adjusting model results to measurements in remote regions, and at high altitudes, leads to a 25% reduction in the multi-model median direct BC forcing from fossil fuel and biofuel burning over the industrial era.

Samset, B. H.; Myhre, G.; Herber, Andreas; Kondo, Yutaka; Li, Shao-Meng; Moteki, N.; Koike, Makoto; Oshima, N.; Schwarz, Joshua P.; Balkanski, Y.; Bauer, S.; Bellouin, N.; Berntsen, T.; Bian, Huisheng; Chin, M.; Diehl, Thomas; Easter, Richard C.; Ghan, Steven J.; Iversen, T.; Kirkevag, A.; Lamarque, Jean-Francois; Lin, Guang; Liu, Xiaohong; Penner, Joyce E.; Schulz, M.; Seland, O.; Skeie, R. B.; Stier, P.; Takemura, T.; Tsigaridis, Kostas; Zhang, Kai

2014-11-27T23:59:59.000Z

254

Global Simulations of Ice nucleation and Ice Supersaturation with an Improved Cloud Scheme in the Community Atmosphere Model  

SciTech Connect (OSTI)

A process-based treatment of ice supersaturation and ice-nucleation is implemented in the National Center for Atmospheric Research (NCAR) Community Atmosphere Model (CAM). The new scheme is designed to allow (1) supersaturation with respect to ice, (2) ice nucleation by aerosol particles and (3) ice cloud cover consistent with ice microphysics. The scheme is implemented with a 4-class 2 moment microphysics code and is used to evaluate ice cloud nucleation mechanisms and supersaturation in CAM. The new model is able to reproduce field observations of ice mass and mixed phase cloud occurrence better than previous versions of the model. Simulations indicate heterogeneous freezing and contact nucleation on dust are both potentially important over remote areas of the Arctic. Cloud forcing and hence climate is sensitive to different formulations of the ice microphysics. Arctic radiative fluxes are sensitive to the parameterization of ice clouds. These results indicate that ice clouds are potentially an important part of understanding cloud forcing and potential cloud feedbacks, particularly in the Arctic.

Gettelman, A.; Liu, Xiaohong; Ghan, Steven J.; Morrison, H.; Park, Sungsu; Conley, Andrew; Klein, Stephen A.; Boyle, James; Mitchell, David; Li, J-L F.

2010-09-28T23:59:59.000Z

255

Development of an atmospheric aerosol model for studies of global budgets and effects of airborne particulate material  

SciTech Connect (OSTI)

A microphysics-removal atmospheric aerosol model (AAM) is developed for use in general circulation models (GCMs) to study global budgets and effects of particulate material. In this model the particle population is composed of a set of log-normal modes whose time evolution due to microphysical processes is described via prognostic equations for an appropriate number of moments of the particle-size distribution. Detailed parameterizations of particle coagulation, sedimentation, dry deposition, and wet removal are developed and implemented into the AAM. The AAM is incorporated into a GCM and is applied to two types of studies: (1) characteristics of the particle wet and dry removal processes, and (2) climatic impact of massive particulate injections following a global nuclear war, with emphasis on the sensitivity of the simulated effects to the inclusion of particle microphysics. Results are discussed.

Giorgi, F.

1986-01-01T23:59:59.000Z

256

Final Technical Report: Development of the DUSTRAN GIS-Based Complex Terrain Model for Atmospheric Dust Dispersion  

SciTech Connect (OSTI)

Activities at U.S. Department of Defense (DoD) training and testing ranges can be sources of dust in local and regional airsheds governed by air-quality regulations. The U.S. Department of Energys Pacific Northwest National Laboratory just completed a multi-year project to develop a fully tested and documented atmospheric dispersion modeling system (DUST TRANsport or DUSTRAN) to assist the DoD in addressing particulate air-quality issues at military training and testing ranges.

Allwine, K Jerry; Rutz, Frederick C.; Shaw, William J.; Rishel, Jeremy P.; Fritz, Brad G.; Chapman, Elaine G.; Hoopes, Bonnie L.; Seiple, Timothy E.

2007-05-01T23:59:59.000Z

257

A study of atmosphere-ocean interaction using a one-dimensional numerical air-sea boundary layer model  

E-Print Network [OSTI]

surface with no allowance for exchange induced by wave action. The model does produce reasonable solutions, in comparison with oceanic data, for the response of the lower atmosphere and the upper ocean to specific. sets of meteorological and oceanic.../2 this function is of the form f(Ri) = (1 + b Ri) , then one obtains ? 3 1/2 2 -1 K (z) = K 62 (gX ) exp(z/W) (z/I + rdI) (1 + b Ri) hw 1 (61) Although KITAIGORODSKII (1961) does not give a specific value of b, it would appear that b = 10/3 would be in line...

Hebenstreit, Gerald Thomas

1974-01-01T23:59:59.000Z

258

THE CARBON-LAND MODEL INTERCOMPARISON PROJECT (C-LAMP): A PROTOTYPE FOR COUPLED BIOSPHERE-ATMOSPHERE MODEL  

E-Print Network [OSTI]

often referred to as Earth System Models (ESMs). While a number of terrestrial and ocean carbon models

Hoffman, Forrest M.

259

Droplet Number Prediction in the NCAR Community Atmosphere Model Steven Ghan Pacific Northwest National Laboratory  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation Proposed Newcatalyst phasesDataTranslocationDiurnalCommittee Draftfor $1.14 Per

260

Prediction of Ice Crystal Number in Community Atmospheric Model (CAM3.0)  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 - SeptemberMicroneedles for medical point ofPowerSaverPredicting The

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261

An Update on Radiative Transfer Model Development at Atmospheric and Environmental Research, Inc.  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)ProductssondeadjustsondeadjustAbout theOFFICEAmes Laboratory Site| Department ofAn InsideAn Update|Update

262

Single-Column Modeling C. J. Walcek Atmospheric Sciences Research Center  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administrationcontroller systemsBi (2)Sharing Smart GridShiftMethodSimwYpes(tm)Single microbeC.J.AC.

263

Development of a GPU-based high-performance radiative transfer model for the Infrared Atmospheric Sounding Interferometer (IASI)  

SciTech Connect (OSTI)

Satellite-observed radiance is a nonlinear functional of surface properties and atmospheric temperature and absorbing gas profiles as described by the radiative transfer equation (RTE). In the era of hyperspectral sounders with thousands of high-resolution channels, the computation of the radiative transfer model becomes more time-consuming. The radiative transfer model performance in operational numerical weather prediction systems still limits the number of channels we can use in hyperspectral sounders to only a few hundreds. To take the full advantage of such high-resolution infrared observations, a computationally efficient radiative transfer model is needed to facilitate satellite data assimilation. In recent years the programmable commodity graphics processing unit (GPU) has evolved into a highly parallel, multi-threaded, many-core processor with tremendous computational speed and very high memory bandwidth. The radiative transfer model is very suitable for the GPU implementation to take advantage of the hardware's efficiency and parallelism where radiances of many channels can be calculated in parallel in GPUs. In this paper, we develop a GPU-based high-performance radiative transfer model for the Infrared Atmospheric Sounding Interferometer (IASI) launched in 2006 onboard the first European meteorological polar-orbiting satellites, METOP-A. Each IASI spectrum has 8461 spectral channels. The IASI radiative transfer model consists of three modules. The first module for computing the regression predictors takes less than 0.004% of CPU time, while the second module for transmittance computation and the third module for radiance computation take approximately 92.5% and 7.5%, respectively. Our GPU-based IASI radiative transfer model is developed to run on a low-cost personal supercomputer with four GPUs with total 960 compute cores, delivering near 4 TFlops theoretical peak performance. By massively parallelizing the second and third modules, we reached 364x speedup for 1 GPU and 1455x speedup for all 4 GPUs, both with respect to the original CPU-based single-threaded Fortran code with the -O{sub 2} compiling optimization. The significant 1455x speedup using a computer with four GPUs means that the proposed GPU-based high-performance forward model is able to compute one day's amount of 1,296,000 IASI spectra within nearly 10 min, whereas the original single CPU-based version will impractically take more than 10 days. This model runs over 80% of the theoretical memory bandwidth with asynchronous data transfer. A novel CPU-GPU pipeline implementation of the IASI radiative transfer model is proposed. The GPU-based high-performance IASI radiative transfer model is suitable for the assimilation of the IASI radiance observations into the operational numerical weather forecast model.

Huang Bormin, E-mail: bormin@ssec.wisc.ed [Space Science and Engineering Center, University of Wisconsin, Madison (United States); Mielikainen, Jarno [Department of Computer Science, University of Eastern Finland, Kuopio (Finland); Oh, Hyunjong; Allen Huang, Hung-Lung [Space Science and Engineering Center, University of Wisconsin, Madison (United States)

2011-03-20T23:59:59.000Z

264

A numerical study of mesoscale convection in a rotating tropical atmosphere  

E-Print Network [OSTI]

similar to the profile of a tropical disturbance. The meso-p forcing of convection consisted of' seven temperature perturbations con- fined below 2. 4 km at intervals of 8 km out to 60 km. The meso-9 forcing of convection comprised of a cosine thermal... perturbation field out to 75 km. Two different classes of simulations were performed. The first part explored how background vorticity affects convection generated by meso-7 and meso-9 forcing. The second part investigated how meso-9 forcing of convection...

Fitzpatrick, Patrick James

1992-01-01T23:59:59.000Z

265

DOE Workshop; Pan-Gass Conference on the Representation of Atmospheric Processes in Weather and Climate Models  

SciTech Connect (OSTI)

This is the first meeting of the whole new GEWEX (Global Energy and Water Cycle Experiment) Atmospheric System Study (GASS) project that has been formed from the merger of the GEWEX Cloud System Study (GCSS) Project and the GEWEX Atmospheric Boundary Layer Studies (GABLS). As such, this meeting will play a major role in energizing GEWEX work in the area of atmospheric parameterizations of clouds, convection, stable boundary layers, and aerosol-cloud interactions for the numerical models used for weather and climate projections at both global and regional scales. The representation of these processes in models is crucial to GEWEX goals of improved prediction of the energy and water cycles at both weather and climate timescales. This proposal seeks funds to be used to cover incidental and travel expenses for U.S.-based graduate students and early career scientists (i.e., within 5 years of receiving their highest degree). We anticipate using DOE funding to support 5-10 people. We will advertise the availability of these funds by providing a box to check for interested participants on the online workshop registration form. We will also send a note to our participants' mailing lists reminding them that the funds are available and asking senior scientists to encourage their more junior colleagues to participate. All meeting participants are encouraged to submit abstracts for oral or poster presentations. The science organizing committee (see below) will base funding decisions on the relevance and quality of these abstracts, with preference given to under-represented populations (especially women and minorities) and to early career scientists being actively mentored at the meeting (e.g. students or postdocs attending the meeting with their advisor).

Morrison, PI Hugh

2012-09-21T23:59:59.000Z

266

Simulations of amphiphilic fluids using mesoscale lattice-Boltzmann and lattice-gas methods  

E-Print Network [OSTI]

We compare two recently developed mesoscale models of binary immiscible and ternary amphiphilic fluids. We describe and compare the algorithms in detail and discuss their stability properties. The simulation results for the cases of self-assembly of ternary droplet phases and binary water-amphiphile sponge phases are compared and discussed. Both models require parallel implementation and deployment on large scale parallel computing resources in order to achieve reasonable simulation times for three-dimensional models. The parallelisation strategies and performance on two distinct parallel architectures are compared and discussed. Large scale three dimensional simulations of multiphase fluids requires the extensive use of high performance visualisation techniques in order to enable the large quantities of complex data to be interpreted. We report on our experiences with two commercial visualisation products: AVS and VTK. We also discuss the application and use of novel computational steering techniques for the more efficient utilisation of high performance computing resources. We close the paper with some suggestions for the future development of both models.

P. J. Love; M. Nekovee; J. Chin; N. Gonzalez-Segredo; P. V. Coveney

2002-12-06T23:59:59.000Z

267

Coupling of a regional atmospheric model (RegCM3) and a regional oceanic model (FVCOM) over the maritime continent  

E-Print Network [OSTI]

Climatological high resolution coupled climate model simulations for the maritime continent have been carried out using the regional climate model (RegCM) version 3 and the finite volume coastal ocean model (FVCOM) ...

Wei, Jun

268

Millimeter radiation from a 3D model of the solar atmosphere I. Diagnosing chromospheric thermal structure  

E-Print Network [OSTI]

Aims. We use advanced 3D NLTE radiative magnetohydrodynamic simulations of the solar atmosphere to carry out detailed tests of chromospheric diagnostics at millimeter and submillimeter wavelengths. Methods. We focused on the diagnostics of the thermal structure of the chromosphere in the wavelength bands from 0.4 mm up to 9.6 mm that can be accessed with the Atacama Large Millimeter/Submillimeter Array (ALMA) and investigated how these diagnostics are affected by the instrumental resolution. Results. We find that the formation height range of the millimeter radiation depends on the location in the simulation domain and is related to the underlying magnetic structure. Nonetheless, the brightness temperature is a reasonable measure of the gas temperature at the effective formation height at a given location on the solar surface. There is considerable scatter in this relationship, but this is significantly reduced when very weak magnetic fields are avoided. Our results indicate that although instrumental smearin...

Loukitcheva, Maria; Carlsson, Mats; White, Stephen

2015-01-01T23:59:59.000Z

269

Application of the 85 GHz ice scattering signature to a global study of mesoscale convective systems  

E-Print Network [OSTI]

It has long been observed that tropical convection tends to cluster, organizing into multicellular mesoscale convective systems (MCS), In convective towers, updrafts on the order of 10 m s-I favor the formation of large, precipitation-sized ice...

Devlin, Karen Irene

1995-01-01T23:59:59.000Z

270

Mesoscale Origin of the Enhanced Cycling-Stability of the Si...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Mesoscale Origin of the Enhanced Cycling-Stability of the Si-Conductive Polymer Anode for Li-ion Batteries. Abstract: Electrode used in lithium-ion battery is invariably a...

271

Design of a high-speed, meso-scale nanopositioners driven by electromagnetic actuators  

E-Print Network [OSTI]

The purpose of this thesis is to generate the design and fabrication knowledge that is required to engineer high-speed, six-axis, meso-scale nanopositioners that are driven by electromagnetic actuators. When compared to ...

Golda, Dariusz, 1979-

2008-01-01T23:59:59.000Z

272

E-Print Network 3.0 - atmospheric model intercomparison Sample...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Project, phase 1 (CMIP1... Abstract An intercomparison of eight EMICs (Earth system Models of Intermediate Complexity) is carried out... doubling in the ... Source:...

273

A grid of MARCS model atmospheres for late-type stars I. Methods and general properties  

E-Print Network [OSTI]

We have constructed a grid of about 10,000 spherically symmetric and plane-parallel models with the MARCS program, and make it available for public use. Parameter ranges are: Teff=2500 to 8000 K, log g =log(GM/R2)= -1 to 5 (cgs) with various masses and radii, [Me/H]=-5 to +1, with [Alpha/Fe] = 0.0 and 0.4 and different choices of C and N abundances to also represent stars of types R, S and N, and with microturbulence parameters from 1 to 5 km/s. We also list fluxes in approximately 108,000 wavelength points. Underlying assumptions in addition to 1D stratification include hydrostatic equilibrium, MLT convection and LTE. A number of general properties of the models are discussed, in relation to the effects of changing blanketing and sphericity. Models are compared with other available grids and excellent agreement is found with plane-parallel models of Castelli and Kurucz within the overlapping parameter range. Although there are departures from the spherically symmetric NextGen models, the agreement with more recent PHOENIX models is gratifying. The models of the grid show regularities, but some interesting departures from general patterns occur for the coolest models due to the molecular opacities. We have tested rules of thumb concerning effects of blanketing and sphericity and found them to often be astonishingly accurate. Some interesting new phenomena have been discovered, such as the intricate coupling between blanketing and sphericity, and the strong effects of carbon enhancement on metal-poor models. We give further details of models and comparisons with observations in subsequent papers.

Bengt Gustafsson; Bengt Edvardsson; Kjell Eriksson; Uffe Graae Jorgensen; Aake Nordlund; Bertrand Plez

2008-05-05T23:59:59.000Z

274

Improving parameterization of scalar transport through vegetation in a coupled ecosystem-atmosphere model  

E-Print Network [OSTI]

Several regional-scale ecosystem models currently parameterize subcanopy scalar transport using a rough-wall boundary eddy diffusivity formulation. This formulation predicts unreasonably high soil evaporation beneath tall, ...

Link, Percy Anne

2008-01-01T23:59:59.000Z

275

Development of a computer model for calculation of radioactive materials into the atmosphere after an accident  

SciTech Connect (OSTI)

Secondary atmospheric contamination with radioactive dust and chemical species deposited on the ground and resuspended by wind occur very widely. This process is particularly pronounced in case of extensive contamination of soil and under extreme weather conditions, for example, during dust storms. The mechanism of wind dust generation consists in the following. At low wind speed U=2-3 m/s, which is most common in midlatitude, small radioactive dust particles (diameter of hundredth of a micron to 10-20 microns) are lifted from soil surface due to turbulent vortexes. Under the gravitational force the particles of 1-2 micron diameter practically do not settle. Larger dust particles cannot remain in the air for a long time: they are lifted by turbulent vortexes and settle, their motion in the wind flow is jump-wise and the interaction of particles with the flow is called saltation /I/. Saltation is the main mechanism of dust generation up to the wind velocity at which wind erosion starts. The size of dust particles can be as large as 100 pm. When dropping they can be ricocheting from ground or pass the impulse to other particles which begin rolling over and jumping up. The process of dust transport by wind can be compared to a chain reaction. At the velocity of 10 m/s large particles of about 500 pm stop skipping and roll over only, while particles of more than 1 mm remain stationary. Thus, the fine fraction is blown out from the polydispersed soil particles. The intensity of wind resuspension of radioactive dust from the ground is characterized either by a resuspension factor or a resuspension rate.

Schershakov, V. [Federal Information Analytical Centre, Obinski (Russia)

1997-11-01T23:59:59.000Z

276

Asian Tracer Experiment and Atmospheric Modeling (TEAM) Project: Draft Field Work Plan for the Asian Long-Range Tracer Experiment  

SciTech Connect (OSTI)

This report provides an experimental plan for a proposed Asian long-range tracer study as part of the international Tracer Experiment and Atmospheric Modeling (TEAM) Project. The TEAM partners are China, Japan, South Korea and the United States. Optimal times of year to conduct the study, meteorological measurements needed, proposed tracer release locations, proposed tracer sampling locations and the proposed durations of tracer releases and subsequent sampling are given. Also given are the activities necessary to prepare for the study and the schedule for completing the preparation activities leading to conducting the actual field operations. This report is intended to provide the TEAM members with the information necessary for planning and conducting the Asian long-range tracer study. The experimental plan is proposed, at this time, to describe the efforts necessary to conduct the Asian long-range tracer study, and the plan will undoubtedly be revised and refined as the planning goes forward over the next year.

Allwine, K Jerry; Flaherty, Julia E.

2007-08-01T23:59:59.000Z

277

Pluto's Atmosphere Does Not Collapse  

E-Print Network [OSTI]

Combining stellar occultation observations probing Pluto's atmosphere from 1988 to 2013 and models of energy balance between Pluto's surface and atmosphere, we conclude that Pluto's atmosphere does not collapse at any point in its 248-year orbit. The occultation results show an increasing atmospheric pressure with time in the current epoch, a trend present only in models with a high thermal inertia and a permanent N2 ice cap at Pluto's north rotational pole.

Olkin, C B; Borncamp, D; Pickles, A; Sicardy, B; Assafin, M; Bianco, F B; Buie, M W; de Oliveira, A Dias; Gillon, M; French, R G; Gomes, A Ramos; Jehin, E; Morales, N; Opitom, C; Ortiz, J L; Maury, A; Norbury, M; Ribas, F B; Smith, R; Wasserman, L H; Young, E F; Zacharias, M; Zacharias, N

2013-01-01T23:59:59.000Z

278

PERFORMANCE OF A SPECTRAL ELEMENT ATMOSPHERIC MODEL SEAM ON THE HP EXEMPLAR SPP2000.  

E-Print Network [OSTI]

discretization strategy taken from NCAR's Community Climate Model Version 3 (CCM3) [9]. Spectral elements have avoiding clustering points at the poles. Secondly, by using a local coordinate system within each element Fournier for helpful comments. This work was supported in part by the U.S. Department of Energy; Oce

Baer, Ferdinand

279

BTRAM: An Interactive Atmospheric Radiative Transfer Model I.M. Chapman1  

E-Print Network [OSTI]

radiance incident on the spectrometer/radiometer. Computer simulations, known as radiative transfer models source of opacity at submillimetre wavelengths where many objects emit most of their energy. Although high altitude observatories (such as the James Clerk Maxwell Telescope (JCMT) in Hawaii and the Atacama

Naylor, David A.

280

Analytical and experimental investigations of gas turbine model combustor acoustics operated at atmospheric pressure  

E-Print Network [OSTI]

Analytical and experimental investigations of gas turbine model combustor acoustics operated the eigenmodes of the combustor results from the resonant coupling between pressure disturbances in the flame distribution within the combustor, except when these frequencies match. When the frequencies are close to each

Paris-Sud XI, Universit de

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281

Manufacturing Ultra-Precision Meso-scale Products by Coining  

SciTech Connect (OSTI)

A method for replicating ultra-precision, meso-scale features onto a near-net-shape metallic blank has been demonstrated. The 'coining' technology can be used to imprint a wide range of features and/or profiles into two opposing surfaces. The instrumented system provides the ability to measure and control the product thickness and total thickness variation (TTV). The coining mechanism relies on kinematic principles to accurately and efficiently produce ultra-precision work pieces without the production of by products such as machining chips, or grinding swarf while preserving surface finish, material structure and overall form. Coining has been developed as a niche process for manufacturing difficult to machine, millimeter size components made from materials that may present hazardous conditions. In the case described in this paper a refractory metal part, tantalum (Ta) was produced with 4 {micro}m peak to valley 50 {micro}m special wavelength sine wave coined into the surface of 50 {micro}m blank. This technique shows promise for use on ductile materials that cannot be precision machined with conventional single crystal diamond tooling and/or has strict requirements on subsurface damage, surface impurities and grain structure. As a production process, it can be used to reduce manufacturing costs where large numbers of ultra-precision, repetitive designs are required and produce parts out of hazardous materials without generating added waste.

Seugling, R M; Davis, P J; Rickens, K; Osmer, J; Brinksmeier, E

2010-02-18T23:59:59.000Z

282

MICRO-SEISMOMETERS VIA ADVANCED MESO-SCALE FABRICATION  

SciTech Connect (OSTI)

The Department of Energy (DOE) and the National Nuclear Security Administration (NNSA) seek revolutionary sensing innovations for the monitoring of nuclear detonations. Performance specifications are to be consistent with those obtainable by only an elite few products available today, but with orders of magnitude reduction in size, weight, power, and cost. The proposed commercial innovation calls upon several technologies including the combination of meso-scale fabrication and assembly, photonics-based displacement / motion detection methods, and the use of digital control electronics . Early Phase II development has demonstrated verified and repeatable sub 2ng noise floor from 3Hz to 100Hz, compact integration of 3-axis prototypes, and robust deployment exercises. Ongoing developments are focusing on low frequency challenges, low power consumption, ultra-miniature size, and low cross axis sensitivity. We are also addressing the rigorous set of specifications required for repeatable and reliable long-term explosion monitoring, including thermal stability, reduced recovery time from mass re-centering and large mechanical shocks, sensitivity stability, and transportability. Successful implementation will result in small, hand-held demonstration units with the ability to address national security needs of the DOE/NNSA. Additional applications envisioned include military/defense, scientific instrumentation, oil and gas exploration, inertial navigation, and civil infrastructure monitoring.

Garcia, Caesar A; Onaran, Guclu; Avenson, Brad; Hall, Neal

2014-11-07T23:59:59.000Z

283

The mean climate of the Community Atmosphere Model (CAM4) in forced SST and fully coupled experiments  

SciTech Connect (OSTI)

The Community Atmosphere Model, version 4 (CAM4) was released as the atmosphere component of the Community Climate System Model, version 4 (CCSM4) and is described. The finite volume dynamical core available in CAM3 is now the default due to its superior transport and conservation properties. Deep convection parameterization changes include a dilute plume calculation of convective available potential energy (CAPE) and the introduction of a formulation for Convective Momentum Transport (CMT). For the cloud fraction an additional calculation is performed following macrophysical state updates that provides improved thermodynamic condistancy. A freeze-drying modification is further made to the cloud fraction calculation in very dry environments, such as arctic Winter, where cloud fractionand cloud water estimates were often inconsistant in CAM3. In CAM4 the finite volume dynamical core leads to a degradation in the excessive trade-wind simulation, but with an accompanying reduction in zonal stresses at higher latitudes. Plume dilution leads to a moister deep tropics alleviating much of the mid-tropospheric dry biases and reduces the persistant precipitation biases over the Arabian peninsular and the southern Indian ocean during the Indian Monsoon. CMT reduces much of the excessive trade-wind biases in eastern ocean basins. The freeze drying modification alleviates much of the high latitude, winter-time excessive cloud bias and improves the associated surface cloud-related energy budget, but the updated cloud macrophysical calculation generally leads to reduced cloud fraction and cloud forcing away from high latitudes. Although there are marginal improvements in time-averaged, large-scale hydrology there are signficant improvements in regional climate features such as the generation of tropical and propagation of stationary waves from the Pacific into mid-latitudes and in the seasonal frequency of Northern Hemisphere blocking events. A 1? versus 2? horizontal resolution of the finite volume 24 dynamical core exhibits signficiant improvements in model climate. Improvements in the fully coupled mean climate between CAM3 and CAM4 are also much more signficant than in forced Sea Surface Temperature (SST) simulations. Furthermore, improvements in the transient characteristics ofthe model climate, documented elsewhere, are substantial.

Neale, Richard; Richter, Jadwiga; Park, Sungsu; Lauritzen, P. H.; Vavrus, Steven J.; Rasch, Philip J.; Zhang, Minghua

2013-07-15T23:59:59.000Z

284

A RECOMMENDED PASQUILL-GIFFORD STABILITY CLASSIFICATION METHOD FOR SAFETY BASIS ATMOSPHERIC DISPERSION MODELING AT SRS  

SciTech Connect (OSTI)

Several of the most common methods for estimating Pasquill-Gifford (PG) stability (turbulence) class were evaluated for use in modeling the radiological consequences of SRS accidental releases using the MELCOR Accident Consequence Code System, Ver. 2 (MACCS2). Evaluation criteria included: (1) the ability of the method to represent diffusion characteristics above a predominantly forested landscape at SRS, (2) suitability of the method to provide data consistent with the formulation of the MACCS2 model, and (3) the availability of onsite meteorological data to support implementation of the method The evaluation resulted in a recommendation that PG stability classification for regulatory applications at SRS should be based on measurements of the standard deviation of the vertical component of wind direction fluctuations, {sigma}{sub e}, collected from the 61-m level of the SRS meteorological towers, and processed in full accordance with EPA-454/R-99-005 (EPA, 2000). This approach provides a direct measurement that is fundamental to diffusion and captures explicitly the turbulence generated by both mechanical and buoyant forces over the characteristic surface (forested) of SRS. Furthermore, due to the potentially significant enhancement of horizontal fluctuations in wind direction from the occurrence of meander at night, the use of {sigma}{sub e} will ensure a reasonably conservative estimate of PG stability class for use in dispersion models that base diffusion calculations on a single value of PG stability class. Furthermore, meteorological data bases used as input for MACCS2 calculations should contain hourly data for five consecutive annual periods from the most recent 10 years.

Hunter, C.

2012-03-28T23:59:59.000Z

285

Multi-model Mean Nitrogen and Sulfur Deposition from the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP): Evaluation of Historical and Projected Future Changes  

SciTech Connect (OSTI)

We present multi-model global datasets of nitrogen and sulfate deposition covering time periods from 1850 to 2100, calculated within the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP). The computed deposition fluxes are compared to surface wet deposition and ice-core measurements. We use a new dataset of wet deposition for 2000-2002 based on critical assessment of the quality of existing regional network data. We show that for present-day (year 2000 ACCMIP time-slice), the ACCMIP results perform similarly to previously published multi-model assessments. The analysis of changes between 1980 and 2000 indicates significant differences between model and measurements over the United States, but less so over Europe. This difference points towards misrepresentation of 1980 NH3 emissions over North America. Based on ice-core records, the 1850 deposition fluxes agree well with Greenland ice cores but the change between 1850 and 2000 seems to be overestimated in the Northern Hemisphere for both nitrogen and sulfur species. Using the Representative Concentration Pathways to define the projected climate and atmospheric chemistry related emissions and concentrations, we find large regional nitrogen deposition increases in 2100 in Latin America, Africa and parts of Asia under some of the scenarios considered. Increases in South Asia are especially large, and are seen in all scenarios, with 2100 values more than double 2000 in some scenarios and reaching >1300 mgN/m2/yr averaged over regional to continental scale regions in RCP 2.6 and 8.5, ~30-50% larger than the values in any region currently (2000). Despite known issues, the new ACCMIP deposition dataset provides novel, consistent and evaluated global gridded deposition fields for use in a wide range of climate and ecological studies.

Lamarque, Jean-Francois; Dentener, Frank; McConnell, J.R.; Ro, C-U; Shaw, Mark; Vet, Robert; Bergmann, D.; Cameron-Smith, Philip; Dalsoren, S.; Doherty, R.; Faluvegi, G.; Ghan, Steven J.; Josse, B.; Lee, Y. H.; MacKenzie, I. A.; Plummer, David; Shindell, Drew; Skeie, R. B.; Stevenson, D. S.; Strode, S.; Zeng, G.; Curran, M.; Dahl-Jensen, D.; Das, S.; Fritzsche, D.; Nolan, M.

2013-08-20T23:59:59.000Z

286

Atmospheric Neutrinos  

E-Print Network [OSTI]

This paper is a brief overview of the theory and experimental data of atmospheric neutrino production at the fiftieth anniversary of the experimental discovery of neutrinos.

Thomas K. Gaisser

2006-12-11T23:59:59.000Z

287

Thermally Induced Chemistry of Meteoritic Complex Organic Molecules: A New Heat-Diffusion Model for the Atmospheric Entry of Meteorites  

E-Print Network [OSTI]

Research over the past four decades has shown a rich variety of complex organic molecular content in some meteorites. This current study is an attempt to gain a better insight into the thermal conditions experienced by these molecules inside meteorites during atmospheric entry. In particular, we wish to understand possible chemical processes that can occur during entry and that might have had an effect on complex organic or prebiotic species that were delivered in this way to the early Earth. A simulation was written in Fortran to model heating by the shock generated during entry and the subsequent thermal diffusion inside the body of a meteorite. Experimental data was used for the thermal parameters of several types of meteorites, including iron-nickel and several classes of chondrites. A Sutton-Graves model of stagnation-point heating was used to calculate peak surface temperatures and an explicit difference formula was used to generate thermal diffusion profiles for both chondrites and iron-nickel type met...

Shingledecker, Christopher N

2014-01-01T23:59:59.000Z

288

Two-moment Bulk Stratiform Cloud Microphysics in the Grid-point Atmospheric Model of IAP LASG (GAMIL)  

SciTech Connect (OSTI)

A two-moment bulk stratiform microphysics scheme, including recently developed physically-based droplet activation/ice nucleation parameterizations has been implemented into the Grid-point Atmospheric Model of IAP LASG (GAMIL) as an effort to enhance the model capability for studying aerosol indirect effects. Unlike the previous one-moment cloud microphysics scheme, the new scheme produces reasonable representation of cloud particle size and number concentration. This scheme captures the observed spatial variations in cloud droplet number concentrations. Simulated ice crystal number concentrations in cirrus clouds qualitatively agree with in-situ observations. The longwave and shortwave cloud forcing are in better agreement with observations. Sensitivity tests show that the column cloud droplet number concentrations calculated from two different droplet activation parameterizations are similar. However, ice crystal number concentration in mixed-phased clouds is sensitive to different heterogeneous freezing formulations. The simulation with high ice crystal number concentration in mixed-phase clouds has less liquid water path and weaker cloud forcing. Furthermore, ice crystal number concentration in cirrus clouds is sensitive to different ice nucleation parameterizations. Sensitivity tests also suggest that impact of pre-existing ice crystals on homogeneous freezing in old clouds should be taken into account.

Shi, Xiangjun; Wang, Bin; Liu, Xiaohong; Wang, Minghuai

2013-05-01T23:59:59.000Z

289

Self-consistent fluid modeling and simulation on a pulsed microwave atmospheric-pressure argon plasma jet  

SciTech Connect (OSTI)

In present study, a pulsed lower-power microwave-driven atmospheric-pressure argon plasma jet has been introduced with the type of coaxial transmission line resonator. The plasma jet plume is with room air temperature, even can be directly touched by human body without any hot harm. In order to study ionization process of the proposed plasma jet, a self-consistent hybrid fluid model is constructed in which Maxwell's equations are solved numerically by finite-difference time-domain method and a fluid model is used to study the characteristics of argon plasma evolution. With a Guass type input power function, the spatio-temporal distributions of the electron density, the electron temperature, the electric field, and the absorbed power density have been simulated, respectively. The simulation results suggest that the peak values of the electron temperature and the electric field are synchronous with the input pulsed microwave power but the maximum quantities of the electron density and the absorbed power density are lagged to the microwave power excitation. In addition, the pulsed plasma jet excited by the local enhanced electric field of surface plasmon polaritons should be the discharge mechanism of the proposed plasma jet.

Chen, Zhaoquan, E-mail: zqchen@aust.edu.cn [Faculty of Physics, St. Petersburg State University, St. Petersburg 198504 (Russian Federation); College of Electrical and Information Engineering, Anhui University of Science and Technology, Huainan, Anhui 232001 (China); Yin, Zhixiang, E-mail: zxyin66@163.com; Chen, Minggong; Hong, Lingli; Hu, Yelin; Huang, Yourui [College of Electrical and Information Engineering, Anhui University of Science and Technology, Huainan, Anhui 232001 (China); Xia, Guangqing; Liu, Minghai [State Key Laboratory of Advanced Electromagnetic Engineering and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China); Kudryavtsev, A. A. [Faculty of Physics, St. Petersburg State University, St. Petersburg 198504 (Russian Federation)

2014-10-21T23:59:59.000Z

290

Scientific uncertainties in atmospheric mercury models III: Boundary and initial conditions, model grid resolution, and Hg(II) reduction mechanism  

SciTech Connect (OSTI)

In this study, the model response in terms of simulated mercury concentration and deposition to boundary condition (BC), initial condition (IC), model grid resolution (12 km versus 36 km), and two alternative Hg(II) reduction mechanisms, was investigated. The model response to the change of gaseous elemental mercury (GEM) concentration from 0 to 2 ngm3 in IC/BC is found to be very linear (r240.99) based on the results of sensitivity simulations in July 2001. An increase of 1 ngm3 of GEM in BC resulted in an increase of 0.81 ngm3 in the monthly average of total mercury concentration, and 1270 ngm2 in the monthly total deposition. IC has similar but weaker effects compared to those of BC. An increase of 1 ngm3 of GEM in IC resulted in an increase of 0.14 ngm3 in the monthly average of total mercury concentration, and 250 ngm2 in the monthly total deposition. Varying reactive gaseous mercury (RGM) or particulate mercury (PHg) in BC/IC has much less significant impact. Simulation results at different grid resolutions show good agreement (slope 0.950 1.026, r 0.816 0.973) in mercury concentration, dry deposition, and total deposition. The agreement in wet deposition is somewhat weaker (slope 0.770 0.794, r 0.685 0.892) due to the difference in emission dilution and simulated precipitation that subsequently change reaction rates in the aqueous phase. Replacing the aqueous Hg(II)-HO2 reduction by either RGM reduction by CO (51018cm3 molecule1 s1) or photoreduction of RGM (1105 s1) gives significantly better model agreement with the wet deposition measured by Mercury Deposition Network (MDN). Possible ranges of the reduction rates are estimated based on model sensitivity results. The kinetic estimate requires further verification by laboratory studies.

Lin, Che-Jen [ORNL; Pongprueksa, Pruek [Lamar University; Lindberg, Steven Eric [ORNL; Jang, Carey [U.S. Environmental Protection Agency, Raleigh, North Carolina; Braverman, Thomas [U.S. Environmental Protection Agency, Raleigh, North Carolina; Bullock, Russell O [NOAA; Ho, Thomas [ORNL; Chu, Hsing-Wei [Lamar University

2008-03-01T23:59:59.000Z

291

Mesoscale Tank Experiments for Investigating Carbon Tetrachloride Biodegradation  

SciTech Connect (OSTI)

Mesoscale tank experiments were performed to simulate bioremediation of saturated zone carbon tetrachloride (CCl4) originating from a vadose zone carbon tetrachloride source. The mesoscale tank is 2-m wide by 2-m high by 3-m long and was constructed of stainless steel, yielding a total volume of 12 m3. Simulated geology within the tank consisted of two unconsolidated sand layers separated by a clay layer containing variable-sized stainless steel tubes that represented fractures within a consolidated porous medium. The thickness of the upper sand layer was approximately 55 cm, the thickness of the virtual fracture layer was 25 cm, and the thickness of the lower sand layer was approximately 98 cm. The water table was located at an elevation of approximately 54 cm from the bottom of the tank. CCl4 was added to the sealed tank by pouring 500 ml of neat CCl4 into a beaker buried approximately 10 cm below the upper sand surface through a stainless steel tube. The CCl4 was then allowed to partition through the reactor over time, eventually coming to equilibrium. Once CCl4 equilibrium had occurred in the saturated zone (~500 ppb); the reactor was bioaugmented with a CCl4 degrading culture enriched from the Subsurface Disposal Area at the INEEL. The culture was grown to a cell density of ~ 1.0 x 108 cells/ml and injected into the simulated aquifer through a center sampling port. Following injection of the culture, an initial aliquot of lactate (1,000 g/L), nitrogen, and phosphorus were added to the reactor. Lactate was injected every 3 5 days for one month. After 1 month of operation, a continuous supply of lactate (1,000 g/L) was pumped into the reactor at an average rate of 50 mL/min. CCl4 concentrations in the unsaturated zone were measured using hollow fiber membrane samplers, while liquid samples were analyzed to monitor levels in the simulated aquifer zone. Samples were also taken for analysis of volatile organic acids and cell density. As would be expected, increases in cell density over the length of the cell correlated with the flow of the water through the cell. One week following injection microbes and lactate, cell numbers were in the range of 5.0 x 106 cells/mL, by the end of the experiment cell numbers had increased to approximately 1.94 x 107 cells/mL. Five days after lactate injection was initiated, chloroform appeared in liquid samples taken for chlorinated VOC analysis. CCl4 concentrations in the liquid phase dropped to approximately 180 ppb. At the conclusion of the batch lactate injection phase of the bioaugmentation, CCl4 levels averaged 40 ppb and chloroform levels averaged 44 ppb. Interestingly, once continuous lactate addition was initiated, CCl4 concentrations in the saturated zone increased with spikes as high as 3,000 ppb. Chloroform concentrations also increased following continuous addition of lactate. Since the CCl4 source in the breaker had been depleted, vadose zone concentrations of CCl4 dropped steadily during addition of lactate to the saturated zone. CCl4 levels of ~ 800 ppmv were noted at the beginning of the experiment, levels decreased to below 200 ppmv by the end of the bioaugmentation phase. No chloroform was noted in the vadose zone during testing.

Brady D. Lee; Robert J. Lenhard

2005-06-01T23:59:59.000Z

292

Mesoscale predictability and background error convariance estimation through ensemble forecasting  

E-Print Network [OSTI]

Over the past decade, ensemble forecasting has emerged as a powerful tool for numerical weather prediction. Not only does it produce the best estimate of the state of the atmosphere, it also could quantify the uncertainties associated with the best...

Ham, Joy L

2002-01-01T23:59:59.000Z

293

32ND INTERNATIONAL COSMIC RAY CONFERENCE, BEIJING 2011 Numerical model of cosmic ray induced ionization in the atmosphere CRAC:CRII  

E-Print Network [OSTI]

¨a Geophysical Observatory, University of Oulu, Finland 2 Ioffe Physical-Technical Institute, St provided the energy spectrum of incoming cosmic rays is known. It computes the background ionization due this a new model we evaluate the ionization effects in the atmosphere caused by several major solar energetic

Mironova, Irina A.

294

Quantifying atmospheric pollution across north america from boreal forest fires: a combined analysis of atmospheric modelling and ground-based remote sensing  

E-Print Network [OSTI]

This paper describes the interpretation of the 2010 summer LIDAR observations from Dal- housie University, Nova Scotia. The GEOS-Chem global 3D chemistry transport model was used to identify the chemical and optical ...

Trigwell, Robert

2011-11-24T23:59:59.000Z

295

Simple solar spectral model for direct and diffuse irradiance on horizontal and tilted planes at the earth's surface for cloudless atmospheres  

SciTech Connect (OSTI)

A new, simple model for calculating clear-sky direct and diffuse spectral irradiance on horizontal and tilted surfaces is presented. The model is based on previously reported simple algorithms and on comparisons with rigorous radiative transfer calculations and limited outdoor measurements. Equations for direct normal irradiance are outlined; and include: Raleigh scattering; aerosol scattering and absorption; water vapor absorption; and ozone and uniformly mixed gas absorption. Inputs to the model include solar zenith angle, collector tilt angle, atmospheric turbidity, amount of ozone and precipitable water vapor, surface pressure, and ground albedo. The model calculates terrestrial spectra from 0.3 to 4.0 ..mu..m with approximately 10 nm resolution. A major goal of this work is to provide researchers with the capability to calculate spectral irradiance for different atmospheric conditions and different collector geometries using microcomputers. A listing of the computer program is provided.

Bird, R.; Riordan, C.

1984-12-01T23:59:59.000Z

296

Developing Model Constraints on Northern Extra-Tropical Carbon Cycling Based on measurements of the Abundance and Isotopic Composition of Atmospheric CO2  

SciTech Connect (OSTI)

The objective of this project was to perform CO2 data syntheses and modeling activities to address two central questions: 1) how much has the seasonal cycle in atmospheric CO2 at northern high latitudes changed since the 1960s, and 2) how well do prognostic biospheric models represent these changes. This project also supported the continuation of the Scripps time series of CO2 isotopes and concentration at ten baseline stations distributed globally.

Keeling, Ralph [UCSD-SIO

2014-12-12T23:59:59.000Z

297

Model testing using Chernobyl data: III. Atmospheric resuspension of radionuclides in Ukrainian regions impacted by Chernobyl fallout  

SciTech Connect (OSTI)

The {open_quotes}Resuspension{close_quotes} scenario is designed to test models for atmospheric resuspension of radionuclides from contaminated soils. Resuspension can be a secondary source of contamination after a release has stopped, as well as a source of contamination for people and areas not exposed to the original release. The test scenario describes three exposure situations: (1) locations within the highly contaminated 30-km zone at Chernobyl, where exposures to resuspended material are probably dominated by local processes; (2) an urban area (Kiev) outside the 30-km zone, where local processes include extensive vehicular traffic; and (3) a location 40 to 60 km west of the Chernobyl reactor, where upwind sources of contamination are important. Input data include characteristics of the {sup 137}Cs ground contamination around specific sites, climatological data for the sites, characteristics of the terrain and topography, and locations of the sampling sites. Predictions are requested for average air concentrations of {sup 137}Cs at specified locations due to resuspension of Chernobyl fallout and for specified resuspension factors and rates. Test data (field measurements) are available for all endpoints. 9 refs., 4 figs., 11 tabs.

Garger, E.K. [Inst. of Radioecology, Kiev (Ukraine); Hoffman, F.O. [SENES Oak Ridge, Inc., TN (United States); Miller, C.W. [Centers for Disease Control and Prevention, Atlanta, GA (United States)

1996-01-01T23:59:59.000Z

298

Source Term Estimation of Radioxenon Released from the Fukushima Dai-ichi Nuclear Reactors Using Measured Air Concentrations and Atmospheric Transport Modeling  

SciTech Connect (OSTI)

Systems designed to monitor airborne radionuclides released from underground nuclear explosions detected radioactive fallout from the Fukushima Daiichi nuclear accident in March 2011. Atmospheric transport modeling (ATM) of plumes of noble gases and particulates were performed soon after the accident to determine plausible detection locations of any radioactive releases to the atmosphere. We combine sampling data from multiple International Modeling System (IMS) locations in a new way to estimate the magnitude and time sequence of the releases. Dilution factors from the modeled plume at five different detection locations were combined with 57 atmospheric concentration measurements of 133-Xe taken from March 18 to March 23 to estimate the source term. This approach estimates that 59% of the 1.241019 Bq of 133-Xe present in the reactors at the time of the earthquake was released to the atmosphere over a three day period. Source term estimates from combinations of detection sites have lower spread than estimates based on measurements at single detection sites. Sensitivity cases based on data from four or more detection locations bound the source term between 35% and 255% of available xenon inventory.

Eslinger, Paul W. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Biegalski, S. [Univ. of Texas at Austin, TX (United States); Bowyer, Ted W. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Cooper, Matthew W. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Haas, Derek A. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Hayes, James C. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Hoffman, Ian [Radiation Protection Bureau, Health Canada, Ottawa, ON (Canada); Korpach, E. [Radiation Protection Bureau, Health Canada, Ottawa, ON (Canada); Yi, Jing [Radiation Protection Bureau, Health Canada, Ottawa, ON (Canada); Miley, Harry S. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Rishel, Jeremy P. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Ungar, R. Kurt [Radiation Protection Bureau, Health Canada, Ottawa, ON (Canada); White, Brian [Radiation Protection Bureau, Health Canada, Ottawa, ON (Canada); Woods, Vincent T. [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)

2014-01-01T23:59:59.000Z

299

ARM - Publications: Science Team Meeting Documents: Evaluation of mesoscale  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD) by Microtops AtmosphericApplication andAn AssessmentARMArcticCloud Fractions and Surface

300

Evaluating atmospheric CO2 inversions at multiple scales over a highly-inventoried agricultural landscape.  

SciTech Connect (OSTI)

An intensive regional research campaign was conducted by the North American Carbon Program (NACP) in 2005 to study the carbon cycle of the highly productive agricultural regions of the Midwestern United States. Forty-_ve di_erent associated projects were spawned across _ve U.S. agencies over the course of nearly a decade involving hundreds of researchers. The primary objective of the project was to investigate the ability of atmospheric inversion techniques to use highly calibrated CO2 mixing ratio data to estimate CO2 exchange over the major croplands of the U.S. Statistics from densely monitored crop production, consisting primarily corn and soybeans, provided the backbone of a well-studied\\bottom up"flux estimate that was used to evaluate the atmospheric inversion results. Three different inversion systems, representing spatial scales varying from high resolution mesoscale, to continental, to global, coupled to different transport models and optimization techniques were compared to the bottom up" inventory estimates. The mean annual CO2-C sink for 2007 from the inversion systems ranged from 120 TgC to 170 TgC, when viewed across a wide variety of inversion setups, with the best" point estimates ranging from 145 TgC to 155 TgC. Inversion-based mean C sink estimates were generally slightly stronger, but statistically indistinguishable,from the inventory estimate whose mean C sink was 135 TgC. The inversion results showed temporal correlations at seasonal lengths while week to week correlations remained low. Comparisons were made between atmospheric transport yields of the two regional inversion systems, which despite having different influence footprints in space and time due to differences in underlying transport models and external forcings, showed similarity when aggregated in space and time.

Schuh, Andrew E.; Lauvaux, Thomas; West, Tristram O.; Denning, A.; Davis, Kenneth J.; Miles, Natasha; Richardson, S. J.; Uliasz, Marek; Lokupitiya, Erandathie; Cooley, Dan; Andrews, Arlyn; Ogle, Stephen

2013-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "atmospheric mesoscale model" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Model Components of the Certification Framework for Geologic Carbon Sequestration Risk Assessment  

SciTech Connect (OSTI)

We have developed a framework for assessing the leakage risk of geologic carbon sequestration sites. This framework, known as the Certification Framework (CF), emphasizes wells and faults as the primary potential leakage conduits. Vulnerable resources are grouped into compartments, and impacts due to leakage are quantified by the leakage flux or concentrations that could potentially occur in compartments under various scenarios. The CF utilizes several model components to simulate leakage scenarios. One model component is a catalog of results of reservoir simulations that can be queried to estimate plume travel distances and times, rather than requiring CF users to run new reservoir simulations for each case. Other model components developed for the CF and described here include fault characterization using fault-population statistics; fault connection probability using fuzzy rules; well-flow modeling with a drift-flux model implemented in TOUGH2; and atmospheric dense-gas dispersion using a mesoscale weather prediction code.

Oldenburg, Curtis M.; Bryant, Steven L.; Nicot, Jean-Philippe; Kumar, Navanit; Zhang, Yingqi; Jordan, Preston; Pan, Lehua; Granvold, Patrick; Chow, Fotini K.

2009-06-01T23:59:59.000Z

302

Atmospheric three-dimensional inverse modeling of regional industrial emissions and global oceanic uptake of carbon tetrachloride  

E-Print Network [OSTI]

Carbon tetrachloride (CCl4) has substantial stratospheric ozone depletion potential and its consumption is controlled under the Montreal Protocol and its amendments. We implement a Kalman filter using atmospheric CCl4 ...

Xiao, X.

303

Investigations of cloud altering effects of atmospheric aerosols using a new mixed Eulerian-Lagrangian aerosol model  

E-Print Network [OSTI]

Industry, urban development, and other anthropogenic influences have substantially altered the composition and size-distribution of atmospheric aerosol particles over the last century. This, in turn, has altered cloud ...

Steele, Henry Donnan, 1974-

2004-01-01T23:59:59.000Z

304

The VAMOS Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx): Goals, platforms, and field operations  

SciTech Connect (OSTI)

The VAMOS Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx) was an international field program designed to make observations of poorly understood but critical components of the coupled climate system of the southeast Pacific. This region is characterized by strong coastal upwelling, the coolest SSTs in the tropical belt, and is home to the largest subtropical stratocumulus deck on Earth. The field intensive phase of VOCALS-REx took place during October and November 2008 and constitutes a critical part of a broader CLIVAR program (VOCALS) designed to develop and promote scientific activities leading to improved understanding, model simulations, and predictions of the southeastern Pacific (SEP) coupled ocean-atmosphere-land system, on diurnal to interannual timescales. The other major components of VOCALS are a modeling program with a model hierarchy ranging from the local to global scales, and a suite of extended observations from regular research cruises, instrumented moorings, and satellites. The two central themes of VOCALS-REx focus upon (a) links between aerosols, clouds and precipitation and their impacts on marine stratocumulus radiative properties, and (b) physical and chemical couplings between the upper ocean and the lower atmosphere, including the role that mesoscale ocean eddies play. A set of hypotheses designed to be tested with the combined field, monitoring and modeling work in VOCALS is presented here. A further goal of VOCALS-REx is to provide datasets for the evaluation and improvement of large-scale numerical models. VOCALS-REx involved five research aircraft, two ships and two surface sites in northern Chile. We describe the instrument payloads and key mission strategies for these platforms and give a summary of the missions conducted.

Wood, R.; Springston, S.; Mechoso, C. R.; Bretherton, C. S.; A.Weller, R.; Huebert, B.; Straneo, F.; Albrecht, B. A.; Coe, H.; Allen, G.; Vaughan, G.; Daum, P.; Fairall, C.; Chand, D.; Klenner, L. G.; Garreaud, R.; Grados, C.; Covert, D. S.; Bates, T. S.; Krejci, R.; Russell, L. M.; Szoeke, S. d.; Brewer, A.; Yuter, S. E.; Chaigneau, A.; Toniazzo, T.; Minnis, P.; Palikonda, R.; Abel, S. J.; Brown, W. O. J.; Williams, S.; Fochesatto, J.; Brioude, J.; Bower, K. N

2011-01-21T23:59:59.000Z

305

Parameterized Mesoscale Forcing Mechanisms for Initiating Numerically Simulated Isolated Multicellular Convection  

E-Print Network [OSTI]

Multicellular Convection ADRIAN M. LOFTUS* School of Meteorology, University of Oklahoma, Norman, Oklahoma DANIEL B. WEBER Center for Analysis and Prediction of Storms, University of Oklahoma, Norman, Oklahoma CHARLES A. DOSWELL III Cooperative Institute for Mesoscale Meteorological Studies, University of Oklahoma

Doswell III, Charles A.

306

Observations of prolific transient luminous event production above a mesoscale convective system in Argentina during  

E-Print Network [OSTI]

in Argentina during the Sprite2006 Campaign in Brazil F. T. São Sabbas,1 M. J. Taylor,2 P.D. Pautet,2 M. Bailey convective system (MCS) over Argentina, as part of the third sprite campaign in Brazil. GOES infrared (IR a mesoscale convective system in Argentina during the Sprite2006 Campaign in Brazil, J. Geophys. Res., 115, A

Thomas, Jeremy N.

307

Larval fish assemblages and mesoscale oceanographic structure along the Mesoamerican Barrier Reef System  

E-Print Network [OSTI]

Larval fish assemblages and mesoscale oceanographic structure along the Mesoamerican Barrier Reef Caribbean region, and contains spawning sites for a number of reef fish species. Despite this, little is known of the distribution and transport of pelagic fish larvae in the area, and basic in situ

308

Combustion in Meso-scale Vortex Chambers Ming-hsun Wu*  

E-Print Network [OSTI]

%. For propane/air combustion, the stability limits ranged from ~ 0.25 to 2 for the 124 mm3 combustor. Methane of a small combustor not only makes the heat generated from the combustion process hard to keep pace1 Combustion in Meso-scale Vortex Chambers Ming-hsun Wu* , Yanxing Wang, Vigor Yang and Richard A

Yang, Vigor

309

Evaluation of mesoscale convective systems in South America using multiple satellite products and an objectbased approach  

E-Print Network [OSTI]

and an objectbased approach E. M. C. Demaria,1 D. A. Rodriguez,2 E. E. Ebert,3 P. Salio,4 F. Su,5 and J. B. Valdes1 to precipitation was mitigating the effect of the errors. Citation: Demaria, E. M. C., D. A. Rodriguez, E. E. Ebert, P. Salio, F. Su, and J. B. Valdes (2011), Evaluation of mesoscale convective systems in South

Ebert, Beth

310

Mesoscale Simulations of a Wind Ramping Event for Wind Energy Prediction  

SciTech Connect (OSTI)

Ramping events, or rapid changes of wind speed and wind direction over a short period of time, present challenges to power grid operators in regions with significant penetrations of wind energy in the power grid portfolio. Improved predictions of wind power availability require adequate predictions of the timing of ramping events. For the ramping event investigated here, the Weather Research and Forecasting (WRF) model was run at three horizontal resolutions in 'mesoscale' mode: 8100m, 2700m, and 900m. Two Planetary Boundary Layer (PBL) schemes, the Yonsei University (YSU) and Mellor-Yamada-Janjic (MYJ) schemes, were run at each resolution as well. Simulations were not 'tuned' with nuanced choices of vertical resolution or tuning parameters so that these simulations may be considered 'out-of-the-box' tests of a numerical weather prediction code. Simulations are compared with sodar observations during a wind ramping event at a 'West Coast North America' wind farm. Despite differences in the boundary-layer schemes, no significant differences were observed in the abilities of the schemes to capture the timing of the ramping event. As collaborators have identified, the boundary conditions of these simulations probably dominate the physics of the simulations. They suggest that future investigations into characterization of ramping events employ ensembles of simulations, and that the ensembles include variations of boundary conditions. Furthermore, the failure of these simulations to capture not only the timing of the ramping event but the shape of the wind profile during the ramping event (regardless of its timing) indicates that the set-up and execution of such simulations for wind power forecasting requires skill and tuning of the simulations for a specific site.

Rhodes, M; Lundquist, J K

2011-09-21T23:59:59.000Z

311

Atmospheric optical calibration system  

DOE Patents [OSTI]

An atmospheric optical calibration system is provided to compare actual atmospheric optical conditions to standard atmospheric optical conditions on the basis of aerosol optical depth, relative air mass, and diffuse horizontal skylight to global horizontal photon flux ratio. An indicator can show the extent to which the actual conditions vary from standard conditions. Aerosol scattering and absorption properties, diffuse horizontal skylight to global horizontal photon flux ratio, and precipitable water vapor determined on a real-time basis for optical and pressure measurements are also used to generate a computer spectral model and for correcting actual performance response of a photovoltaic device to standard atmospheric optical condition response on a real-time basis as the device is being tested in actual outdoor conditions. 7 figs.

Hulstrom, R.L.; Cannon, T.W.

1988-10-25T23:59:59.000Z

312

High altitude atmospheric discharges according to the runaway air breakdown mechanism  

SciTech Connect (OSTI)

High altitude optical transients - red sprites, blue jets, and elves - are modeled in the context of the relativistic electron runaway air breakdown mechanism. These emissions are usually associated with large mesoscale convective systems (hereafter MCS). In thunderstorms cloud electrification proceeds over a time scale long enough to permit the conducting atmosphere above the cloud to polarize and short out the thunderstorm electric field. When a lightning strike rapidly neutralizes a cloud charge layer runaway driving fields can develop in the stratosphere and mesosphere. According to present simulations of the full runaway process the variety of observed optical emissions are due to the nature of the normal lightning event in the MCS that kick starts the runaway avalanche. In this paper the authors describe some details of the model, present the results of the evolution of the primary electron population, and summarize the initial conditions necessary for different types of discharges. Two companion papers present (a) the predicted optical, gamma ray, and radio emissions caused by these electrical discharges, and (b) the time evolution of the secondary electron population and its implications in terms of observables.

Symbalisty, E.; Roussel-Dupre, R.; Yukhimuk, V.; Taranenko, Y.

1997-04-01T23:59:59.000Z

313

Radar range measurements in the atmosphere.  

SciTech Connect (OSTI)

The earth's atmosphere affects the velocity of propagation of microwave signals. This imparts a range error to radar range measurements that assume the typical simplistic model for propagation velocity. This range error is a function of atmospheric constituents, such as water vapor, as well as the geometry of the radar data collection, notably altitude and range. Models are presented for calculating atmospheric effects on radar range measurements, and compared against more elaborate atmospheric models.

Doerry, Armin Walter

2013-02-01T23:59:59.000Z

314

Jellylike atmospheric particles resist chemical aging Findings will affect scientific models of cloud formation and light absorption  

E-Print Network [OSTI]

sulfuric acid, helping prevent acid rain, but its nitrogen component can also fertilize open bodies of pinene SOM and adipic acid, have shown that a drop in humidity can send these common aerosols, pinene and adipic acid, are common in the Earth's atmosphere; pinene is essentially a scent released

315

Cloud-to-ground lightning characteristics of warm season Mesoscale Convection Systems in the Central United States: 1992-1993  

E-Print Network [OSTI]

This study provides a detailed analysis of cloud-to-aphics. ground (CG) lightning flashes within individual Mesoscale Convective Systems (MCSs) that occurred in the Central United States during May-August of 1992 and 1993. Analysis of the CG...

Hoeth, Brian Richard

2012-06-07T23:59:59.000Z

316

The evolution of total lightning and radar reflectivity characteristics of two mesoscale convective systems over Houston, Texas  

E-Print Network [OSTI]

originated in the convective or transition regions. Both in-situ charging mechanisms created by the development of the mesoscale updraft and charge advection by the front-to-rear flow likely contribute to the increased electrification and lightning...

Hodapp, Charles Lee

2009-05-15T23:59:59.000Z

317

Modeling, Analysis and Simulation of Multiscale Preferential Flow - 8/05-8/10 - Final Report  

SciTech Connect (OSTI)

The research agenda of this project are: (1) Modeling of preferential transport from mesoscale to macroscale; (2) Modeling of fast flow in narrow fractures in porous media; (3) Pseudo-parabolic Models of Dynamic Capillary Pressure; (4) Adaptive computational upscaling of flow with inertia from porescale to mesoscale; (5) Adaptive modeling of nonlinear coupled systems; and (6) Adaptive modeling and a-posteriori estimators for coupled systems with heterogeneous data.

Ralph Showalter; Malgorzata Peszynska

2012-07-03T23:59:59.000Z

318

New Mesoscale Multimodal Imaging of Cellular Communication Between Microbe  

Office of Science (SC) Website

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched5 IndustrialIsadore Perlman, 1960 The ErnestLouisMichael J.|Neutronand Plant in the

319

Posters Mesoscale Simulations of Convective Systems with Data Assimilation During  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 - September 2006PhotovoltaicSeptember 22, 2014SocietyJ. Dudhia51 Posters7

320

Technical Sessions Parameterization of Convective Clouds, Mesoscale Convective Systems,  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security AdministrationcontrollerNanocrystallineForeign ObjectOUR8, 2013Battelle:TechnicalP. Daum L.

Note: This page contains sample records for the topic "atmospheric mesoscale model" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Integrated Mesoscale Architectures for Sustainable Catalysis (IMASC) | U.S.  

Office of Science (SC) Website

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched5 IndustrialIsadore Perlman,Bios High EnergyElianeScienceScience| U.S. DOE(SC)DOE

322

Mesoscale fracture fabric and paleostress along the San Andreas fault at SAFOD  

E-Print Network [OSTI]

Studies of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Approved by: Chair of Committee, Judith Chester Committee Members, Frederick Chester David Schechter Head of Department... of Advisory Committee: Dr. Judith Chester Spot cores from Phase 1 drilling of the main borehole at the San Andreas Fault Observatory at Depth (SAFOD) were mapped to characterize the mesoscale structure and infer paleostress at depth. Cores were oriented...

Almeida, Rafael Vladimir

2009-05-15T23:59:59.000Z

323

Representation of the mesoscale wind field using a line integral technique  

E-Print Network [OSTI]

REPPESENTATION OF THE MESOSCALE WIND FIELD USING A LINE INTEGRAL TECHNII1UE A Thesis by JOHN SEBASTIAN TRARES, JR. Submitted to the Graduate College of Texas ASM University in partial fulfillment of the requirement for the degree of MASTER... OF SCIENCE May 1982 Major Subject: Meteorology REPRESENTATION OF THE HESOSCALE WIND FIELD USING A LINE INTEGRAL TECHNIQUE A Thesis by JOHN SESASTIAN TRARES, JR. Approved as to style and content by: Chairman of Committee Nember ember Head of Depar...

Trares, John S

1982-01-01T23:59:59.000Z

324

atmospheric dispersion coefficient: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

the earth surface. In general, the atmospheric motion is driven by the intense solar energy arriving at the equator 3 A GIS-based atmospheric dispersion model Computer...

325

atmospheric dispersion calculations: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

the earth surface. In general, the atmospheric motion is driven by the intense solar energy arriving at the equator 4 A GIS-based atmospheric dispersion model Computer...

326

atmospheric dispersion experiment: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

the earth surface. In general, the atmospheric motion is driven by the intense solar energy arriving at the equator 2 A GIS-based atmospheric dispersion model Computer...

327

Atmospheric Sciences Program Department of Marine, Earth and Atmospheric Sciences (MEAS)  

E-Print Network [OSTI]

atmospheric chemistry/air quality, boundary layer and air pollution meteorology, regional/global climatology MODELING OF MULTIPLE AIR POLLUTANTS AT URBAN AND REGIONAL SCALES Our atmosphere is a complex systemAtmospheric Sciences Program Department of Marine, Earth and Atmospheric Sciences (MEAS) (http

Parker, Matthew D. Brown

328

DE-SC0001933 DOE Final Report  

SciTech Connect (OSTI)

The overall objective of this study was to improve the representation of regional ocean circulation in the North Pacific by using high resolution atmospheric forcing that accurately represents mesoscale processes in ocean-atmosphere regional (North Pacific) model configuration. The goal was to assess the importance of accurate representation of mesoscale processes in the atmosphere and the ocean on large scale circulation. This is an important question, as mesoscale processes in the atmosphere which are resolved by the high resolution mesoscale atmospheric models such as Weather Research and Forecasting (WRF), are absent in commonly used atmospheric forcing such as CORE forcing, employed in e.g. the Community Climate System Model (CCSM).

Cerovecki, Ivana

2014-11-14T23:59:59.000Z

329

Evaluation of A New Mixed-Phase Cloud Microphysics Parameterization with the NCAR Climate Atmospheric Model (CAM3) and ARM Observations Fourth Quarter 2007 ARM Metric Report  

SciTech Connect (OSTI)

Mixed-phase clouds are composed of a mixture of cloud droplets and ice crystals. The cloud microphysics in mixed-phase clouds can significantly impact cloud optical depth, cloud radiative forcing, and cloud coverage. However, the treatment of mixed-phase clouds in most current climate models is crude and the partitioning of condensed water into liquid droplets and ice crystals is prescribed as temperature dependent functions. In our previous 2007 ARM metric reports a new mixed-phase cloud microphysics parameterization (for ice nucleation and water vapor deposition) was documented and implemented in the NCAR Community Atmospheric Model Version 3 (CAM3). The new scheme was tested against the Atmospheric Radiation Measurement (ARM) Mixed-phase Arctic Cloud Experiment (M-PACE) observations using the single column modeling and short-range weather forecast approaches. In this report this new parameterization is further tested with CAM3 in its climate simulations. It is shown that the predicted ice water content from CAM3 with the new parameterization is in better agreement with the ARM measurements at the Southern Great Plain (SGP) site for the mixed-phase clouds.

X Liu; SJ Ghan; S Xie; J Boyle; SA Klein

2007-09-30T23:59:59.000Z

330

Modeling of collision-induced infrared absorption spectra of H2-H2 pairs in the fundamental band at temperatures from 20 to 300 K. [Planetary atmospheres  

SciTech Connect (OSTI)

The 20-300 K free-free rotovibrational collision-induced absorption (RV CIA) spectra of H2-H2 pairs are presently obtained by a numerical method which, in addition to closely matching known CIA spectra of H2-H2, can reproduce the results of the quantum-mechanical computations to within a few percent. Since the spectral lineshape parameters are derivable by these means from the lowest three quantum-mechanical spectral moments, these outer-planet atmosphere-pertinent model spectra may be computed on even small computers. 35 refs.

Borysow, A. (Michigan Technological University, Houghton (United States))

1991-08-01T23:59:59.000Z

331

Ecosystem feedbacks to climate change in California: Development, testing, and analysis using a coupled regional atmosphere and land-surface model (WRF3-CLM3.5)  

SciTech Connect (OSTI)

A regional atmosphere model [Weather Research and Forecasting model version 3 (WRF3)] and a land surface model [Community Land Model, version 3.5 (CLM3.5)] were coupled to study the interactions between the atmosphere and possible future California land-cover changes. The impact was evaluated on California's climate of changes in natural vegetation under climate change and of intentional afforestation. The ability of WRF3 to simulate California's climate was assessed by comparing simulations by WRF3-CLM3.5 and WRF3-Noah to observations from 1982 to 1991. Using WRF3-CLM3.5, the authors performed six 13-yr experiments using historical and future large-scale climate boundary conditions from the Geophysical Fluid Dynamics Laboratory Climate Model version 2.1 (GFDL CM2.1). The land-cover scenarios included historical and future natural vegetation from the Mapped Atmosphere-Plant-Soil System-Century 1 (MC1) dynamic vegetation model, in addition to a future 8-million-ha California afforestation scenario. Natural vegetation changes alone caused summer daily-mean 2-m air temperature changes of -0.7 to +1 C in regions without persistent snow cover, depending on the location and the type of vegetation change. Vegetation temperature changes were much larger than the 2-m air temperature changes because of the finescale spatial heterogeneity of the imposed vegetation change. Up to 30% of the magnitude of the summer daily-mean 2-m air temperature increase and 70% of the magnitude of the 1600 local time (LT) vegetation temperature increase projected under future climate change were attributable to the climate-driven shift in land cover. The authors projected that afforestation could cause local 0.2-1.2 C reductions in summer daily-mean 2-m air temperature and 2.0-3.7 C reductions in 1600 LT vegetation temperature for snow-free regions, primarily because of increased evapotranspiration. Because some of these temperature changes are of comparable magnitude to those projected under climate change this century, projections of climate and vegetation change in this region need to consider these climate-vegetation interactions.

Subin, Z.M.; Riley, W.J.; Kueppers, L.M.; Jin, J.; Christianson, D.S.; Torn, M.S.

2010-11-01T23:59:59.000Z

332

The Dynamics of Deterministic Chaos in Numerical Weather Prediction Models  

E-Print Network [OSTI]

Atmospheric weather systems are coherent structures consisting of discrete cloud cells forming patterns of rows/streets, mesoscale clusters and spiral bands which maintain their identity for the duration of their appreciable life times in the turbulent shear flow of the planetary Atmospheric Boundary Layer. The existence of coherent structures (seemingly systematic motion) in turbulent flows has been well established during the last 20 years of research in turbulence. Numerical weather prediction models based on the inherently non-linear Navier-Stokes equations do not give realistic forecasts because of the following inherent limitations: (1) the non-linear governing equations for atmospheric flows do not have exact analytic solutions and being sensitive to initial conditions give chaotic solutions characteristic of deterministic chaos (2) the governing equations do not incorporate the dynamical interactions and co-existence of the complete spectrum of turbulent fluctuations which form an integral part of the large coherent weather systems (3) limitations of available computer capacity necessitates severe truncation of the governing equations, thereby generating errors of approximations (4) the computer precision related roundoff errors magnify the earlier mentioned uncertainties exponentially with time and the model predictions become unrealistic. The accurate modelling of weather phenomena therefore requires alternative concepts and computational techniques. In this paper a universal theory of deterministic chaos applicable to the formation of coherent weather structures in the ABL is presented.

A. Mary Selvam

2003-10-07T23:59:59.000Z

333

Analysis of azimuthal mode dynamics of mesoscale eddies  

E-Print Network [OSTI]

Rossby wave modes. The results appear to be in excellent qualitative agree- ment with Fli erl's (1977) analytic solutions. But the real advantage to numerical simulation is in the application to nonlinear models and arbitrary initial conditions. Mc...Wi lli ams and Fli erl ( 1979) presented the results of an extensive parameter survey using their two-mode non- linear quasigeostrophic model. The primary result is that nonlinear processes impede dispersion in intense vortices, so that friction be...

McCalpin, John David

1984-01-01T23:59:59.000Z

334

Upscaling Calcite Growth Rates From the Mesoscale to the Macroscale  

SciTech Connect (OSTI)

Quantitative prediction of mineral reaction rates in the subsurface remains a daunting task partly because a key parameter for macroscopic models, the reactive site density, is poorly constrained. Here we report atomic force microscopy (AFM) measurements on the calcite surface of monomolecular step densities, treated as equivalent to the reactive site density, as a function of aqueous calcium-to-carbonate ratio and saturation index. Data for the obtuse step orientation are combined with existing step velocity measurements to generate a model that predicts overall macroscopic calcite growth rates. The model is quantitatively consistent with several published macroscopic rates under a range of alkaline solution conditions, particularly for two of the most comprehensive data sets without the need for additional fit parameters. The model reproduces peak growth rates and its functional form is simple enough to be incorporated into reactive transport or other macroscopic models designed for predictions in porous media. However, it currently cannot model equilibrium, pH effects, and may overestimate rates at high aqueous calcium-to-carbonate ratios. The discrepancies in rates at high calcium-to-carbonate ratios may be due to differences in pre-treatment, such as exposing the seed material to SI 1.0 to generate/develop growth hillocks, or other factors.

Bracco, Jacquelyn N [ORNL; Stack, Andrew G [ORNL; Steefel, Carl I [Lawrence Berkeley National Laboratory (LBNL)

2013-01-01T23:59:59.000Z

335

Atmospheric Aerosol Systems | EMSL  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Science Themes Atmospheric Aerosol Systems Overview Atmospheric Aerosol Systems Biosystem Dynamics & Design Energy Materials & Processes Terrestrial & Subsurface Ecosystems...

336

Florian SEITZ: Atmospheric and oceanic impacts to Earth rotations numerical studies with a dynamic Earth system model  

E-Print Network [OSTI]

with a dynamic Earth system model (completed in October 2004) Variations of Earth rotation are caused Earth system model DyMEG has been developed. It is based on the balance of angular momentum

Schuh, Harald

337

DOE research on atmospheric aerosols  

SciTech Connect (OSTI)

Atmospheric aerosols are the subject of a significant component of research within DOE`s environmental research activities, mainly under two programs within the Department`s Environmental Sciences Division, the Atmospheric Radiation Measurement (ARM) Program and the Atmospheric Chemistry Program (ACP). Research activities conducted under these programs include laboratory experiments, field measurements, and theoretical and modeling studies. The objectives and scope of these programs are briefly summarized. The ARM Program is the Department`s major research activity focusing on atmospheric processes pertinent to understanding global climate and developing the capability of predicting global climate change in response to energy related activities. The ARM approach consists mainly of testing and improving models using long-term measurements of atmospheric radiation and controlling variables at highly instrumented sites in north central Oklahoma, in the Tropical Western Pacific, and on the North Slope of Alaska. Atmospheric chemistry research within DOE addresses primarily the issue of atmospheric response to emissions from energy-generation sources. As such this program deals with the broad topic known commonly as the atmospheric source-receptor sequence. This sequence consists of all aspects of energy-related pollutants from the time they are emitted from their sources to the time they are redeposited at the Earth`s surface.

Schwartz, S.E.

1995-11-01T23:59:59.000Z

338

MODELING THE TRANSPORT AND CHEMICAL EVOLUTION OF ONSHORE AND OFFSHORE EMISSIONS AND THEIR IMPACT ON LOCAL AND REGIONAL AIR QUALITY USING A VARIABLE-GRID-RESOLUTION AIR QUALITY MODEL  

SciTech Connect (OSTI)

This document, the project's first semiannual report, summarizes the research performed from 04/17/2003 through 10/16/2003. Portions of the research in several of the project's eight tasks were completed, and results obtained are briefly presented. We have tested the applicability of two different atmospheric boundary layer schemes for use in air quality model simulations. Preliminary analysis indicates that a scheme that uses sophisticated atmospheric boundary physics resulted in better simulation of atmospheric circulations. We have further developed and tested a new surface data assimilation technique to improve meteorological simulations, which will also result in improved air quality model simulations. Preliminary analysis of results indicates that using the new data assimilation technique results in reduced modeling errors in temperature and moisture. Ingestion of satellite-derived sea surface temperatures into the mesoscale meteorological model led to significant improvements in simulated clouds and precipitation compared to that obtained using traditional analyzed sea surface temperatures. To enhance the capabilities of an emissions processing system so that it can be used with our variable-grid-resolution air quality model, we have identified potential areas for improvements. Also for use in the variable-grid-resolution air quality model, we have tested a cloud module offline for its functionality, and have implemented and tested an efficient horizontal diffusion algorithm within the model.

Kiran Alapaty

2003-12-01T23:59:59.000Z

339

Air-sea interaction at contrasting sites in the Eastern Tropical Pacific : mesoscale variability and atmospheric convection at 10N  

E-Print Network [OSTI]

The role of ocean dynamics in driving air-sea interaction is examined at two contrasting sites on 125W in the eastern tropical Pacific Ocean using data from the Pan American Climate Study (PACS) field program. Analysis ...

Farrar, J. Thomas (John Thomas), 1976-

2007-01-01T23:59:59.000Z

340

URBAN ATMOSPHERIC OBSERVATORY (UAO) FIRST PLANNING WORKSHOP, JANUARY 27-28-2003. WORKSHOP SUMMARY.  

SciTech Connect (OSTI)

The Urban Atmospheric Observatory (UAO) First Planning Workshop was held on 27-28 January 2003 at the Environmental Measurements Laboratory (EML) in downtown Manhattan, New York City. The meeting was well attended by local, state, and national administrators, as well as scientists and engineers from the national laboratories and academia. The real-time intensive UAO is a necessary step toward the development and validation of new technologies in support of the New York City emergency management and anti-terrorism effort. The real-time intensive UAO will be a dense array of meteorological instrumentation, remote sensing and satellite products and model output, as well as radiation detection, gamma spectrometer and aerosol measurements focused onto a small area in the heart of Manhattan. Such a test-bed, developed in a somewhat homogeneous urban area, and with a well-developed communication and data collection backbone, will be of immense utility for understanding how models of all scales can be improved and how they can best be integrated into the city's emergency program. The goal of the First Planning Workshop was to bring together a small group of experts in the fields of urban meteorology, modeling from mesoscale to fine-mesh computational fluid dynamics, instrumentation, communications and visualization, in order to (1) establish the importance of the observational program, (2) define the most efficient and cost-effective design for the program, (3) define needed intensive observational efforts and establish a schedule, and (4) define the importance of the UAO in emergency operations. The workshop achieved its goals with the enthusiastic participation of over forty persons. There was a synthesis of ideas towards a world-class facility that would benefit both immediate emergency management activities and, over an extended time, the entire field of urban meteorology and contaminant dispersion modeling.

REYNOLDS,R.M.; LEE,H.N.

2003-03-27T23:59:59.000Z

Note: This page contains sample records for the topic "atmospheric mesoscale model" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
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We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

North Pacific Mesoscale Coupled Air-Ocean Simulations Compared with Observations  

SciTech Connect (OSTI)

Executive summary The main objective of the study was to investigate atmospheric and ocean interaction processes in the western Pacific and, in particular, effects of significant ocean heat loss in the Kuroshio and Kuroshio Extension regions on the lower and upper atmosphere. It is yet to be determined how significant are these processes are on climate scales. The understanding of these processes led us also to development of the methodology of coupling the Weather and Research Forecasting model with the Parallel Ocean Program model for western Pacific regional weather and climate simulations. We tested NCAR-developed research software Coupler 7 for coupling of the WRF and POP models and assessed its usability for regional-scale applications. We completed test simulations using the Coupler 7 framework, but implemented a standard WRF model code with options for both one- and two-way mode coupling. This type of coupling will allow us to seamlessly incorporate new WRF updates and versions in the future. We also performed a long-term WRF simulation (15 years) covering the entire North Pacific as well as high-resolution simulations of a case study which included extreme ocean heat losses in the Kuroshio and Kuroshio Extension regions. Since the extreme ocean heat loss occurs during winter cold air outbreaks (CAO), we simulated and analyzed a case study of a severe CAO event in January 2000 in detail. We found that the ocean heat loss induced by CAOs is amplified by additional advection from mesocyclones forming on the southern part of the Japan Sea. Large scale synoptic patterns with anomalously strong anticyclone over Siberia and Mongolia, deep Aleutian Low, and the Pacific subtropical ridge are a crucial setup for the CAO. It was found that the onset of the CAO is related to the breaking of atmospheric Rossby waves and vertical transport of vorticity that facilitates meridional advection. The study also indicates that intrinsic parameterization of the surface fluxes within the WRF model needs more evaluation and analysis.

Koracin, Darko; Cerovecki, Ivana; Vellore, Ramesh; Mejia, John; Hatchett, Benjamin; McCord, Travis; McLean, Julie; Dorman, Clive

2013-04-11T23:59:59.000Z

342

Where do fossil fuel carbon dioxide emissions from California go? An analysis based on radiocarbon observations and an atmospheric transport model  

SciTech Connect (OSTI)

Characterizing flow patterns and mixing of fossil fuel-derived CO{sub 2} is important for effectively using atmospheric measurements to constrain emissions inventories. Here we used measurements and a model of atmospheric radiocarbon ({sup 14}C) to investigate the distribution and fluxes of atmospheric fossil fuel CO{sub 2} across the state of California. We sampled {sup 14}C in annual C{sub 3} grasses at 128 sites and used these measurements to test a regional model that simulated anthropogenic and ecosystem CO{sub 2} fluxes, transport in the atmosphere, and the resulting {sup 14}C of annual grasses ({Delta}{sub g}). Average measured {Delta}{sub g} in Los Angeles, San Francisco, the Central Valley, and the North Coast were 27.7 {+-} 20.0, 44.0 {+-} 10.9, 48.7 {+-} 1.9, and 59.9 {+-} 2.5{per_thousand}, respectively, during the 2004-2005 growing season. Model predictions reproduced regional patterns reasonably well, with estimates of 27.6 {+-} 2.4, 39.4 {+-} 3.9, 46.8 {+-} 3.0, and 59.3 {+-} 0.2{per_thousand} for these same regions and corresponding to fossil fuel CO{sub 2} mixing ratios (Cf) of 13.7, 6.1, 4.8, and 0.3 ppm. {Delta}{sub g} spatial heterogeneity in Los Angeles and San Francisco was higher in the measurements than in the predictions, probably from insufficient spatial resolution in the fossil fuel inventories (e.g., freeways are not explicitly included) and transport (e.g., within valleys). We used the model to predict monthly and annual transport patterns of fossil fuel-derived CO{sub 2} within and out of California. Fossil fuel CO{sub 2} emitted in Los Angeles and San Francisco was predicted to move into the Central Valley, raising Cf above that expected from local emissions alone. Annually, about 21, 39, 35, and 5% of fossil fuel emissions leave the California airspace to the north, east, south, and west, respectively, with large seasonal variations in the proportions. Positive correlations between westward fluxes and Santa Ana wind conditions were observed. The southward fluxes over the Pacific Ocean were maintained in a relatively coherent flow within the marine boundary layer, while the eastward fluxes were more vertically dispersed. Our results indicate that state and continental scale atmospheric inversions need to consider areas where concentration measurements are sparse (e.g., over the ocean to the south and west of California), transport within and across the marine boundary layer, and terrestrial boundary layer dynamics. Measurements of {Delta}{sub g} can be very useful in constraining these estimates.

Riley, W.J.; Hsueh, D.Y.; Randerson, J.T.; Fischer, M.L.; Hatch, J.G.; Pataki, D.E.; Wang, W.; Goulden, M.L.

2008-05-01T23:59:59.000Z

343

High-Resolution Large-Eddy Simulations of Scalar Transport in Atmospheric Boundary Layer Flow over Complex Terrain  

E-Print Network [OSTI]

of Electric Power Industry, Chiba, Japan FOTINI KATOPODES CHOW Department of Civil and Environmental to the choice of numerical simulation parameters than is typically needed for mean wind field predictions. Large-eddy simulation is used in a mesoscale setting, providing modeling advantages through the use of robust turbulence

Chow, Fotini Katopodes

344

TRANSMISSION SPECTRA OF TRANSITING PLANET ATMOSPHERES: MODEL VALIDATION AND SIMULATIONS OF THE HOT NEPTUNE GJ 436b FOR THE JAMES WEBB SPACE TELESCOPE  

SciTech Connect (OSTI)

We explore the transmission spectrum of the Neptune-class exoplanet GJ 436b, including the possibility that its atmospheric opacity is dominated by a variety of nonequilibrium chemical products. We also validate our transmission code by demonstrating close agreement with analytic models that use only Rayleigh scattering or water vapor opacity. We find broad disagreement with radius variations predicted by another published model. For GJ 436b, the relative coolness of the planet's atmosphere, along with its implied high metallicity, may make it dissimilar in character compared to 'hot Jupiters'. Some recent observational and modeling efforts suggest low relative abundances of H{sub 2}O and CH{sub 4} present in GJ 436b's atmosphere, compared to calculations from equilibrium chemistry. We include these characteristics in our models and examine the effects of absorption from methane-derived higher-order hydrocarbons. To our knowledge, the effects of these nonequilibrium chemical products on the spectra of close-in giant planets have not previously been investigated. Significant absorption from HCN and C{sub 2}H{sub 2} is found throughout the infrared, while C{sub 2}H{sub 4} and C{sub 2}H{sub 6} are less easily seen. We perform detailed simulations of James Webb Space Telescope observations, including all likely noise sources, and find that we will be able to constrain chemical abundance regimes from this planet's transmission spectrum. For instance, the width of the features at 1.5, 3.3, and 7 {mu}m indicates the amount of HCN versus C{sub 2}H{sub 2} present. The NIRSpec prism mode will be useful due to its large spectral range and the relatively large number of photo-electrons recorded per spectral resolution element. However, extremely bright host stars like GJ 436 may be better observed with a higher spectroscopic resolution mode in order to avoid detector saturation. We find that observations with the MIRI low-resolution spectrograph should also have high signal-to-noise in the 5-10 {mu}m range due to the brightness of the star and the relatively low spectral resolution (R {approx} 100) of this mode.

Shabram, Megan [Department of Astronomy, University of Florida, 211 Bryant Space Center, Gainesville, FL 32611 (United States); Fortney, Jonathan J. [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); Greene, Thomas P.; Freedman, Richard S. [Space Science and Astrobiology Division, NASA Ames Research Center, Mail Stop 245-3, Moffett Field, CA 94035 (United States)

2011-02-01T23:59:59.000Z

345

Impact of horizontal resolution on simulation of precipitation extremes in an aqua-planet version of the Community Atmosphere Model (CAM)  

SciTech Connect (OSTI)

One key question regarding current climate models is whether the projection of climate extremes converges to a realistic representation as the spatial and temporal resolutions of the model are increased. Ideally the model extreme statistics should approach a fixed distribution once the resolutions are commensurate with the characteristic length and time scales of the processes governing the formation of the extreme phenomena of interest. In this study, a series of AGCM runs with idealized 'aquaplanet-steady-state' boundary conditions have been performed with the Community Atmosphere Model CAM3 to investigate the effect of horizontal resolution on climate extreme simulations. The use of the aquaplanet framework highlights the roles of model physics and dynamics and removes any apparent convergence in extreme statistics due to better resolution of surface boundary conditions and other external inputs. Assessed at a same large spatial scale, the results show that the horizontal resolution and time step have strong effects on the simulations of precipitation extremes. The horizontal resolution has a much stronger impact on precipitation extremes than on mean precipitation. Updrafts are strongly correlated with extreme precipitation at tropics at all the resolutions, while positive low-tropospheric temperature anomalies are associated with extreme precipitation at mid-latitudes.

Li, F.; Collins, W.D.; Wehner, M.F.; Williamson, D.L.; Olson, J.G.; Algieri, C.

2011-03-01T23:59:59.000Z

346

Satellite Observations of Mesoscale Eddy-Induced Ekman Pumping1 Peter Gaube ,Dudley B. Chelton, Roger M. Samelson, Michael G. Schlax, Larry W. O'Neill2  

E-Print Network [OSTI]

Satellite Observations of Mesoscale Eddy-Induced Ekman Pumping1 Peter Gaube ,Dudley B. Chelton;Three mechanisms for self-induced Ekman pumping in the interiors of mesoscale ocean eddies temperature (SST) field, which generates a stress curl and therefore Ekman pumping in regions of crosswind SST

347

Satellite Observations of Mesoscale Eddy-Induced Ekman Pumping1 Peter Gaube ,Dudley B. Chelton, Roger M. Samelson, Michael G. Schlax, Larry W. O'Neill2  

E-Print Network [OSTI]

Satellite Observations of Mesoscale Eddy-Induced Ekman Pumping1 Peter Gaube ,Dudley B. Chelton;Three mechanisms for self-induced Ekman pumping in the interiors of mesoscale ocean eddies generates a curl of the stress and therefore Ekman pumping in regions of crosswind SST gradients

Samelson, Roger

348

Diurnal cycle of air pollution in the Kathmandu Valley, Nepal: 2. Modeling results  

E-Print Network [OSTI]

After completing a 9-month field experiment studying air pollution and meteorology in the Kathmandu Valley, Nepal, we set up the mesoscale meteorological model MM5 to simulate the Kathmandu Valley's meteorology with a ...

Panday, Arnico K.

349

The identification of HCN and HNC in Carbon Stars: Model Atmospheres, Synthetic Spectra and Fits to Observations in the 2.7-4.0 micron Region  

E-Print Network [OSTI]

Model carbon star atmospheres and synthetic spectra have been calculated using the recent HCN/HNC vibration rotation linelist of Harris et al. (2002) ApJ, 578, 657. The calculations are repeated using only HCN lines and show that HNC has a significant effect upon the temperature, density and optical depth of a stellar atmosphere. We fit synthetic spectra in the 2.7-4.0 micron region to observed ISO spectra of the carbon stars WZ Cas and TX Psc obtained by Aoki et al. (1998), A&A, 340, 222. These fits allow us to identify absorption by HNC in the spectrum of WZ Cas at 2.8-2.9 microns, and to determine new independent estimates of effective temperature and log(Nc)/log(No). The findings reported here indicate that absorption by both HCN and HNC is needed to fully explain the observed stellar spectra and represent the first identification of HNC in a star. Q branch absorption by the HCN $\\Delta v_2=1$, $\\Delta v_3=1$ and $\\Delta v_1=1$, $\\Delta v_2=-1$ bands at 3.55 and 3.86 microns respectively, are identified in the spectrum of WZ Cas.

G. J. Harris; Ya. V. Pavlenko; H. R. A. Jones; J. Tennyson

2003-06-06T23:59:59.000Z

350

SPRAYTRAN 1.0 Users Guide: A GIS-Based Atmospheric Spray Droplet Dispersion Modeling System  

SciTech Connect (OSTI)

SPRAY TRANsport (SPRAYTRAN) is a comprehensive dispersion modeling system that is used to simulate the offsite drift of pesticides from spray applications. SPRAYTRAN functions as a console application within Environmental System Research Institutes ArcMap Geographic Information System (Version 9.x) and integrates the widely-used, U.S. Environmental Protection Agency (EPA)-approved CALifornia PUFF (CALPUFF) dispersion model and model components to simulate longer-range transport and diffusion in variable terrain and spatially/temporally varying meteorological (e.g., wind) fields. Area sources, which are used to define spray blocks in SPRAYTRAN, are initialized using output files generated from a separate aerial-spray-application model called AGDISP (AGricultural DISPersal). The AGDISP model is used for estimating the amount of pesticide deposited to the spray block based on spraying characteristics (e.g., pesticide type, spray nozzles, and aircraft type) and then simulating the near-field (less than 300-m) drift from a single pesticide application. The fraction of pesticide remaining airborne from the AGDISP near-field simulation is then used by SPRAYTRAN for simulating longer-range (greater than 300 m) drift and deposition of the pesticide.

Allwine, K Jerry; Rutz, Frederick C.; Droppo, James G.; Rishel, Jeremy P.; Chapman, Elaine G.; Bird, S. L.; Thistle, Harold W.

2006-09-20T23:59:59.000Z

351

Derivation of two models for noise due to atmospheric turbulence for improvement of resolution of beamforming algorithm  

E-Print Network [OSTI]

' the local wind conditions (speed and direction). The first model is idealized and a closed form solution is allowed. That is, the error induced by the wind can be eliminated within the beamforming algorithm. The second model is less idealized and a closed... in the direction of the acoustic waves propagating from the acoustic source is u. An array of AI acoustic sensors is assembled and a coordinate system is defined. Each sensor has position vector r, and a reference sensor is designated. See Figure 1. Note...

Hetmaniak, Joseph Christopher

2012-06-07T23:59:59.000Z

352

E-Print Network 3.0 - atmospheric diffusion experiments Sample...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

technical coupling software... linking the main model components of present-day Earth System models (ESMs), i.e. the atmosphere... be followed to couple ocean and atmosphere...

353

E-Print Network 3.0 - atmospheric fine elemental Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

technical coupling software... linking the main model components of present-day Earth System models (ESMs), i.e. the atmosphere... be followed to couple ocean and atmosphere...

354

E-Print Network 3.0 - atmospheric experiment recherche Sample...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

technical coupling software... linking the main model components of present-day Earth System models (ESMs), i.e. the atmosphere... be followed to couple ocean and atmosphere...

355

E-Print Network 3.0 - atmospheric interference Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

technical coupling software... linking the main model components of present-day Earth System models (ESMs), i.e. the atmosphere... be followed to couple ocean and atmosphere...

356

E-Print Network 3.0 - atmospheric stability conditions Sample...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

wind park model considering atmospheric stability. Wind... : A simple analytical wind park model considering atmospheric stability. Wind Energy, 13, 459-469. 12... : A...

357

Modeling the barotropic response of the global ocean to atmospheric wind and pressure forcing -comparisons with observations  

E-Print Network [OSTI]

-G. Model outputs are compared to in situ observations with tide gauge data (TG) and bottom pressure gauge data (BPR), and also with T/P altimetric cross over points (noted CO). Intercomparisons were performed/P and Jason altimeters deliver very accurate data sets (within 2 centimeter global error for T/P). How- ever

358

New formulae to evaluate the atmospheric layers of precipitable water and gases, applicable in solar radiation computing models  

E-Print Network [OSTI]

in solar radiation computing models V. B0103descu Energetica, Centrale Electrice, Polytechn. Inst irradiance. In this context, the relatively low density of solar radiation recording stations favoured measurements. Reviews and classifications of the main calculations procedures of solar radiation have been

Paris-Sud XI, Université de

359

Design and fabrication of a meso-scale stirling engine and combustor.  

SciTech Connect (OSTI)

Power sources capable of supplying tens of watts are needed for a wide variety of applications including portable electronics, sensors, micro aerial vehicles, and mini-robotics systems. The utility of these devices is often limited by the energy and power density capabilities of batteries. A small combustion engine using liquid hydrocarbon fuel could potentially increase both power and energy density by an order of magnitude or more. This report describes initial development work on a meso-scale external combustion engine based on the Stirling cycle. Although other engine designs perform better at macro-scales, we believe the Stirling engine cycle is better suited to small-scale applications. The ideal Stirling cycle requires efficient heat transfer. Consequently, unlike other thermodynamic cycles, the high heat transfer rates that are inherent with miniature devices are an advantage for the Stirling cycle. Furthermore, since the Stirling engine uses external combustion, the combustor and engine can be scaled and optimized semi-independently. Continuous combustion minimizes issues with flame initiation and propagation. It also allows consideration of a variety of techniques to promote combustion that would be difficult in a miniature internal combustion engine. The project included design and fabrication of both the engine and the combustor. Two engine designs were developed. The first used a cylindrical piston design fabricated with conventional machining processes. The second design, based on the Wankel rotor geometry, was fabricated by through-mold electroforming of nickel in SU8 and LIGA micromolds. These technologies provided the requisite precision and tight tolerances needed for efficient micro-engine operation. Electroformed nickel is ideal for micro-engine applications because of its high strength and ductility. A rotary geometry was chosen because its planar geometry was more compatible with the fabrication process. SU8 lithography provided rapid prototypes to verify the design. A final high precision engine was created via LIGA. The micro-combustor was based on an excess enthalpy concept. Development of a micro-combustor included both modeling and experiments. We developed a suite of simulation tools both in support of the design of the prototype combustors, and to investigate more fundamental aspects of combustion at small scales. Issues of heat management and integration with the micro-scale Stirling engine were pursued using CFD simulations. We found that by choice of the operating conditions and channel dimensions energy conversion occurs by catalysis-dominated or catalysis-then-homogeneous phase combustion. The purpose of the experimental effort in micro-combustion was to study the feasibility and explore the design parameters of excess enthalpy combustors. The efforts were guided by the necessity for a practical device that could be implemented in a miniature power generator, or as a stand-alone device used for heat generation. Several devices were fabricated and successfully tested using methane as the fuel.

Echekki, Tarek (Sandia National Laboratories, Livermore, CA); Haroldsen, Brent L. (Sandia National Laboratories, Livermore, CA); Krafcik, Karen L. (Sandia National Laboratories, Livermore, CA); Morales, Alfredo Martin (Sandia National Laboratories, Livermore, CA); Mills, Bernice E. (Sandia National Laboratories, Livermore, CA); Liu, Shiling (Sandia National Laboratories, Livermore, CA); Lee, Jeremiah C. (Sandia National Laboratories, Livermore, CA); Karpetis, Adionos N. (Sandia National Laboratories, Livermore, CA); Chen, Jacqueline H. (Sandia National Laboratories, Livermore, CA); Ceremuga, Joseph T. (Sandia National Laboratories, Livermore, CA); Raber, Thomas N. (Sandia National Laboratories, Livermore, CA); Hekmuuaty, Michelle A. (Sandia National Laboratories, Livermore, CA)

2005-05-01T23:59:59.000Z

360

Mesoscale Self-Assembly: Capillary Bonds and Negative Menisci Ned Bowden, Scott R. J. Oliver, and George M. Whitesides*  

E-Print Network [OSTI]

Mesoscale Self-Assembly: Capillary Bonds and Negative Menisci Ned Bowden, Scott R. J. Oliver., Cambridge, Massachusetts 02138 ReceiVed: September 2, 1999 This paper describes the self-assembly) that examined the self-assembly of hexagonal plates of PDMS (F ) 1.05 g/cm3) that had a density close

Prentiss, Mara

Note: This page contains sample records for the topic "atmospheric mesoscale model" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

October 1986 R. H. Johnson 721 Lower-Tropospheric Warming and Drying in Tropical Mesoscale Convective Systems  

E-Print Network [OSTI]

October 1986 R. H. Johnson 721 Lower-Tropospheric Warming and Drying in Tropical Mesoscale Convective Systems: Implications for the Problem of Cumulus Parameterization By Richard H. Johnson Department beneath the stratiform com- ponents of these systems (Houze, 1977; Zipser, 1977; Johnson and Kriete, 1982

Johnson, Richard H.

362

A Comprehensive Parameterization of Heterogeneous Ice Nucleation of Dust Surrogate: Laboratory Study with Hematite Particles and Its Application to Atmospheric Models  

SciTech Connect (OSTI)

A new heterogeneous ice nucleation parameterization that covers a wide temperature range (-36 ?C to -78 ?C) is presented. Developing and testing such an ice nucleation parameterization, which is constrained through identical experimental conditions, is critical in order to accurately simulate the ice nucleation processes in cirrus clouds. The surface-scaled ice nucleation efficiencies of hematite particles, inferred by ns, were derived from AIDA (Aerosol Interaction and Dynamics in the Atmosphere) cloud chamber measurements under water subsaturated conditions that were realized by continuously changing temperature (T) and relative humidity with respect to ice (RHice) in the chamber. Our measurements showed several different pathways to nucleate ice depending on T and RHice conditions. For instance, almost independent freezing was observed at -60 ?C < T < -50 ?C, where RHice explicitly controlled ice nucleation efficiency, while both T and RHice played roles in other two T regimes: -78 ?C < T < -60 ?C and -50 ?C < T < -36 ?C. More specifically, observations at T colder than -60 ?C revealed that higher RHice was necessary to maintain constant ns, whereas T may have played a significant role in ice nucleation at T warmer than -50 ?C. We implemented new ns parameterizations into two cloud models to investigate its sensitivity and compare with the existing ice nucleation schemes towards simulating cirrus cloud properties. Our results show that the new AIDA-based parameterizations lead to an order of magnitude higher ice crystal concentrations and inhibition of homogeneous nucleation in colder temperature regions. Our cloud simulation results suggest that atmospheric dust particles that form ice nuclei at lower temperatures, below -36 ?C, can potentially have stronger influence on cloud properties such as cloud longevity and initiation when compared to previous parameterizations.

Hiranuma, Naruki; Paukert, Marco; Steinke, Isabelle; Zhang, Kai; Kulkarni, Gourihar R.; Hoose, Corinna; Schnaiter, Martin; Saathoff, Harald; Mohler, Ottmar

2014-12-10T23:59:59.000Z

363

On testing the significance of atmospheric response to smoke from the Kuwaiti oil fires using the Los Alamos general circulation model  

SciTech Connect (OSTI)

The response of the Los Alamos atmospheric general circulation model to the smoke from the Kuwaiti oil fires set in 1991 is examined. The model has an interactive soot transport module that uses a Lagrangian tracer particle scheme. The statistical significance of the results is evaluated using a methodology based on the classic Student`s t test. Among various estimated smoke emission rates and associated visible absorption coefficients, the worst- and best-case scenarios are selected. In each of the scenarios, an ensemble of 10, 30-day June simulations are conducted with the smoke, and are compared to the same 10 June simulations without the smoke. The results of the worst-case scenario show that a statistically significant wave train pattern propagates eastward-poleward downstream from the source. The signals favorably compare with the observed climate anomalies in summer 1991, albeit some possible El Nino-Southern Oscillation effects were involved in the actual climate. The results of the best-case (i.e., least-impact) scenario show that the significance is rather small but that its general pattern is quite similar to that in the worst-case scenario. 24 refs., 5 figs.

Chih-Yue Jim Kao; Glatzmaier, G.A.; Malone, R.C. [Los Alamos National Lab., NM (United States)

1994-07-20T23:59:59.000Z

364

Atmospheric science and power production  

SciTech Connect (OSTI)

This is the third in a series of scientific publications sponsored by the US Atomic Energy Commission and the two later organizations, the US Energy Research and Development Adminstration, and the US Department of Energy. The first book, Meteorology and Atomic Energy, was published in 1955; the second, in 1968. The present volume is designed to update and to expand upon many of the important concepts presented previously. However, the present edition draws heavily on recent contributions made by atmospheric science to the analysis of air quality and on results originating from research conducted and completed in the 1970s. Special emphasis is placed on how atmospheric science can contribute to solving problems relating to the fate of combustion products released into the atmosphere. The framework of this book is built around the concept of air-quality modeling. Fundamentals are addressed first to equip the reader with basic background information and to focus on available meteorological instrumentation and to emphasize the importance of data management procedures. Atmospheric physics and field experiments are described in detail to provide an overview of atmospheric boundary layer processes, of how air flows around obstacles, and of the mechanism of plume rise. Atmospheric chemistry and removal processes are also detailed to provide fundamental knowledge on how gases and particulate matter can be transformed while in the atmosphere and how they can be removed from the atmosphere. The book closes with a review of how air-quality models are being applied to solve a wide variety of problems. Separate analytics have been prepared for each chapter.

Randerson, D. (ed.)

1984-07-01T23:59:59.000Z

365

Northerly surface wind events over the eastern North Pacific Ocean : spatial distribution, seasonality, atmospheric circulation, and forcing  

E-Print Network [OSTI]

ECMWF and NCEP numerical weather prediction models, Mon.atmospheric numerical weather prediction model. The

Taylor, Stephen V.

2006-01-01T23:59:59.000Z

366

Atmospheric chemistry impacts and feedbacks on the global carbon cycle  

E-Print Network [OSTI]

prediction. Issues to be addressed include the quantification of the impact of the atmospheric oxidation and the oxidative state of the atmosphere. The end goal is to create a model that can quantitatively predict is required to: Predict 3-D atmospheric CO2 production as a function of the CCSM3 atmospheric chemistry module

367

Collection Policy: SOIL, CROP AND ATMOSPHERIC SCIENCES Subject Scope | Priority Tables | Other policies . . .  

E-Print Network [OSTI]

. q Microclimatology. q Air pollution. q Atmospheric modeling. q The Engineering Library hasCollection Policy: SOIL, CROP AND ATMOSPHERIC SCIENCES Subject Scope | Priority Tables | Other; atmospheric phenomena, prediction, modeling; geographical information systems; soil survey; microbial

Angenent, Lars T.

368

ISO-SWS calibration and the accurate modelling of cool-star atmospheres - III. A0 to G2 stars  

E-Print Network [OSTI]

Vega, Sirius, Beta Leo, Alpha Car and Alpha Cen A belong to a sample of twenty stellar sources used for the calibration of the detectors of the Short-Wavelength Spectrometer on board the Infrared Space Observatory (ISO-SWS). While general problems with the calibration and with the theoretical modelling of these stars are reported in Decin et al. (2002), each of these stars is discussed individually in this paper. As demonstrated in Decin et al. (2002), it is not possible to deduce the effective temperature, the gravity and the chemical composition from the ISO-SWS spectra of these stars. But since ISO-SWS is absolutely calibrated, the angular diameter of these stellar sources can be deduced from their ISO-SWS spectra, which consequently yields the stellar radius (R), the gravity-inferred mass (M) and the luminosity (L) for these stars. These deduced parameters are confronted with other published values and the goodness-of-fit between observed ISO-SWS data and the corresponding synthetic spectrum is discussed.

L. Decin; B. Vandenbussche; C. Waelkens; K. Eriksson; B. Gustafsson; B. Plez; A. J. Sauval

2002-07-29T23:59:59.000Z

369

ISO-SWS calibration and the accurate modelling of cool-star atmospheres - IV. G9 to M2 stars  

E-Print Network [OSTI]

presented. The 2.38 -- 4.08 micron wavelength-range of band 1 of ISO-SWS (Short-Wavelength Spectrometers on board of the Infrared Space Observatory) in which many different molecules -- with their own dependence on each of the stellar parameters -- are absorbing, enables us to estimate the effective temperature, the gravity, the microturbulence, the metallicity, the CNO-abundances, the 12C/13C-ratio and the angular diameter from the ISO-SWS data. Using the Hipparcos' parallax, the radius, luminosity and gravity-inferred mass are derived. The stellar parameters obtained are in good agreement with other published values, though also some discrepancies with values deduced by other authors are noted. For a few stars (Delta Dra, Xi Dra, Alpha Tuc, H Sco and Alpha Cet) some parameters -- e.g. the CNO-abundances -- are derived for the first time. By examining the correspondence between different ISO-SWS observations of the same object and between the ISO-SWS data and the corresponding synthetic spectrum, it is shown that the relative accuracy of ISO-SWS in band 1 (2.38 -- 4.0 micron) is better than 2% for these high-flux sources. The high level of correspondence between observations and theoretical predictions, together with a confrontation of the estimated Teff(ISO) value with Teff-values derived from colours -- which demonstrates the consistency between V-K, BC(K), Teff and the angular diameter derived from optical or IR data -- proves that both the used MARCS models to derive the stellar quantities and the flux calibration of the ISO-SWS detectors have reached a high level of reliability.

L. Decin; B. Vandenbussche; C. Waelkens; G. Decin; K. Eriksson; B. Gustafsson; B. Plez; A. J. Sauval

2002-07-30T23:59:59.000Z

370

3.021J / 1.021J / 10.333J / 18.361J / 22.00J Introduction to Modeling and Simulation, Spring 2008  

E-Print Network [OSTI]

This course explores the basic concepts of computer modeling and simulation in science and engineering. We'll use techniques and software for simulation, data analysis and visualization. Continuum, mesoscale, atomistic and ...

Buehler, Markus

371

Cold domes over the warm pool: a study of the properties of cold domes produced by mesoscale convective systems during TOGA COARE  

E-Print Network [OSTI]

Mesoscale convective systems (MCSs) are known to cool the subcloud layer by the introduction of penetrative downdrafts to the surface, resulting in the formation of cold domes (also known as cold pools). Five MCSs sampled during the Tropical Ocean...

Caesar, Kathy-Ann Lois

1995-01-01T23:59:59.000Z

372

HEATING THE ATMOSPHERE ABOVE SUNSPOTS  

E-Print Network [OSTI]

become fragmented and twisted, and where they generate the necessary energy to heat the solar coronaHEATING THE ATMOSPHERE ABOVE SUNSPOTS David Alexander and Neal E. Hurlburt Lockheed Martin Solar, University of Cambridge, Cambridge, CB3 9EW, UK Abstract We present our results of a hybrid model of sunspots

Rucklidge, Alastair

373

NEAMS FPL M2 Milestone Report: Development of a UO? Grain Size Model using Multicale Modeling and Simulation  

SciTech Connect (OSTI)

This report summarizes development work funded by the Nuclear Energy Advanced Modeling Simulation program's Fuels Product Line (FPL) to develop a mechanistic model for the average grain size in UO? fuel. The model is developed using a multiscale modeling and simulation approach involving atomistic simulations, as well as mesoscale simulations using INL's MARMOT code.

Tonks, Michael R. [Idaho National Laboratory (INL), Idaho Falls, ID (United States); Zhang, Yongfeng [Idaho National Laboratory (INL), Idaho Falls, ID (United States); Bai, Xianming [Idaho National Laboratory (INL), Idaho Falls, ID (United States)

2014-06-01T23:59:59.000Z

374

Review of Wind Energy Forecasting Methods for Modeling Ramping Events  

SciTech Connect (OSTI)

Tall onshore wind turbines, with hub heights between 80 m and 100 m, can extract large amounts of energy from the atmosphere since they generally encounter higher wind speeds, but they face challenges given the complexity of boundary layer flows. This complexity of the lowest layers of the atmosphere, where wind turbines reside, has made conventional modeling efforts less than ideal. To meet the nation's goal of increasing wind power into the U.S. electrical grid, the accuracy of wind power forecasts must be improved. In this report, the Lawrence Livermore National Laboratory, in collaboration with the University of Colorado at Boulder, University of California at Berkeley, and Colorado School of Mines, evaluates innovative approaches to forecasting sudden changes in wind speed or 'ramping events' at an onshore, multimegawatt wind farm. The forecast simulations are compared to observations of wind speed and direction from tall meteorological towers and a remote-sensing Sound Detection and Ranging (SODAR) instrument. Ramping events, i.e., sudden increases or decreases in wind speed and hence, power generated by a turbine, are especially problematic for wind farm operators. Sudden changes in wind speed or direction can lead to large power generation differences across a wind farm and are very difficult to predict with current forecasting tools. Here, we quantify the ability of three models, mesoscale WRF, WRF-LES, and PF.WRF, which vary in sophistication and required user expertise, to predict three ramping events at a North American wind farm.

Wharton, S; Lundquist, J K; Marjanovic, N; Williams, J L; Rhodes, M; Chow, T K; Maxwell, R

2011-03-28T23:59:59.000Z

375

Some challenges of middle atmosphere data assimilation  

E-Print Network [OSTI]

Some challenges of middle atmosphere data assimilation 1234567 89A64BC7DEF72B4 8629EEC7C72DEEE5.1256/qj.05.87 Some challenges of middle atmosphere data assimilation By S. POLAVARAPU1,2, T. G. SHEPHERD2 Data assimilation is employed at operational weather forecast centres to combine measurements and model

Wirosoetisno, Djoko

376

Doctoral Programs Atmospheric, Oceanic & Space Sciences  

E-Print Network [OSTI]

University of Michigan Space Research Building 2455 Hayward Street Ann Arbor, MI 48109-2143 aoss Katherine E. White, Ann Arbor The Regents of the University of Michigan Research areas Atmospheric Science Atmospheric Dynamics Climate, Climate Modeling & Climate Change Clouds & Precipitation Paleoclimate, Ice

Eustice, Ryan

377

Climate Sciences: Atmospheric Thermodynamics  

E-Print Network [OSTI]

1 Climate Sciences: Atmospheric Thermodynamics Instructor: Lynn Russell, NH343 http://aerosol.ucsd.edu/courses.html Text: Curry & Webster Atmospheric Thermodynamics Ch1 Composition Ch2 Laws Ch3 Transfers Ch12 Energy Climate Sciences: Atmospheric Thermodynamics Instructor: Lynn Russell, NH343 http

Russell, Lynn

378

5, 60416076, 2005 Atmospheric  

E-Print Network [OSTI]

opportunity to examine atmospheric oxidation in a megacity that has more pollution than typical USACPD 5, 6041­6076, 2005 Atmospheric oxidation in the Mexico City Metropolitan Area T. R. Shirley et.atmos-chem-phys.org/acpd/5/6041/ SRef-ID: 1680-7375/acpd/2005-5-6041 European Geosciences Union Atmospheric Chemistry

Boyer, Edmond

379

Time dependences of atmospheric Carbon dioxide fluxes  

E-Print Network [OSTI]

Understanding the lifetime of CO2 in the atmosphere is critical for predictions regarding future climate changes. A simple mass conservation analysis presented here generates tight estimations for the atmosphere's retention time constant. The analysis uses a leaky integrator model that combines the observed deficit (only less than 40% of CO2 produced from combustion of fossil fuels is actually retained in the atmosphere, while more than 60% is continuously shed) with the exponential growth of fossil fuel burning. It reveals a maximum characteristic time of less than 23 year for the transfer of atmospheric CO2 to a segregation sink. This time constant is further constrained by the rapid disappearance of 14C after the ban of atmospheric atomic bomb tests, which provides a lower limit of 18 years for this transfer. The study also generates evaluations of other CO2 fluxes, exchange time constants and volumes exchanged. Analysis of large harmonic oscillations of atmospheric CO2 concentration, often neglected in th...

DeSalvo, Riccardo

2014-01-01T23:59:59.000Z

380

Rainfall-Runoff Modelling of Meso-Scale Catchments in the Upper Ewaso  

E-Print Network [OSTI]

, but growing demand for irrigation water on its foothills produces water shortage in the lowlands. Water founded River Water Users Associations, but their work is hindered by a lack of knowledge on the present and future availability of water resources. This study tries to make a contribution to better water

Richner, Heinz

Note: This page contains sample records for the topic "atmospheric mesoscale model" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Surface Stresses and Turbulent Fluxes: Problems in Mesoscale Modeling over Terrain  

E-Print Network [OSTI]

: Turbulent mixing in breaking waves (Epifanio and Qian, 2008) LES for breaking mountain wave Flow past a hill) = Dx Ly (u, v, w) = Dy One kinematic condition (no flow through the boundary): w = u h x + v h y at the boundary and combine with the kinematic condition Lx ui,j,0 vi,j,0 wi,j,0 = f (Dx i,j , interior) , Ly

382

Mesoscale environmental models accompanying convection in the Texas HIPLEX region / by Mark Edward Humbert  

E-Print Network [OSTI]

with convection is upward motion at all levels with a maximum value just prior to max1mum convect1ve intensity. Days without convection showed a cont1nual vertical turbulent m1xing of moisture from a shallow boundary layer to the 700 mb level. Lack... of 4 g kg 1 are observed. The moisture content increases at the 22 Post Big Spring Midland Robert Lee 4 500 mb cn 0 O m 8 L. cn 6 x 4 2 700 mb . . ~ ''. ~' . ~ / r 12 10 850 mb 15 18 21 00 03 Time (GNT hours) Fig. 9. Time profiles...

Humbert, Mark Edward

1980-01-01T23:59:59.000Z

383

Author's personal copy Mesoscale modeling of electric double layer capacitors with three-dimensional  

E-Print Network [OSTI]

, cylindrical, and spherical electrodes or pores. EDLCs with highly ordered porous electrodes. EDLC with ordered bimodal meso- porous formulations for simulating electric double layer capacitors (EDLCs) with three-dimensional ordered structures

Pilon, Laurent

384

Modal Bin Hybrid Model: A Surface Area Consistent, Triple Moment Sectional Method for Use in Process-oriented Modeling of Atmospheric Aerosols  

SciTech Connect (OSTI)

A triple moment sectional method, Modal Bin Hybrid Model (MBHM), has been developed. In addition to number and mass (volume), surface area is predicted (and preserved), which is important for gas-to-particle mass transfer and light extinction cross section. The performance of MBHM was evaluated against double moment sectional (DMS) methods with various size resolutions up to BIN256 (BINx: x is number of sections over three orders of magnitude in size, ?logD = 3/x) for simulating evolution of particles under simultaneously occurring nucleation, condensation and coagulation processes. Because MBHM gives a physically consistent form of the intra-sectional distributions, errors and biases of MBHM at BIN4-8 resolution were almost equivalent to those of DMS at BIN16-32 resolution for various important variables such as the moments Mk (k: 0, 2, 3), dMk/dt, and the number and volume of particles larger than a certain diameter. Another important feature of MBHM is that only a single bin is adequate to simulate full aerosol dynamics for particles whose size distribution can be approximated by a single lognormal mode. This flexibility is useful for process-oriented (multi category and/or mixing state) modeling: primary aerosols whose size parameters would not differ substantially in time and space can be expressed by a single or a small number of modes, whereas secondary aerosols whose size changes drastically from one to several hundred nanometers can be expressed by a number of modes. Added dimensions can be applied to MBHM to represent mixing state or photo-chemical age for aerosol mixing state studies.

Kajino, Mizuo; Easter, Richard C.; Ghan, Steven J.

2013-09-10T23:59:59.000Z

385

Regional Climate Model Projections for the State of Washington  

SciTech Connect (OSTI)

Global climate models do not have sufficient spatial resolution to represent the atmospheric and land surface processes that determine the unique regional heterogeneity of the climate of the State of Washington. If future large-scale weather patterns interact differently with the local terrain and coastlines than current weather patterns, local changes in temperature and precipitation could be quite different from the coarse-scale changes projected by global models. Regional climate models explicitly simulate the interactions between the large-scale weather patterns simulated by a global model and the local terrain. We have performed two 100-year climate simulations using the Weather and Research Forecasting (WRF) model developed at the National Center for Atmospheric Research (NCAR). One simulation is forced by the NCAR Community Climate System Model version 3 (CCSM3) and the second is forced by a simulation of the Max Plank Institute, Hamburg, global model (ECHAM5). The mesoscale simulations produce regional changes in snow cover, cloudiness, and circulation patterns associated with interactions between the large-scale climate change and the regional topography and land-water contrasts. These changes substantially alter the temperature and precipitation trends over the region relative to the global model result or statistical downscaling. To illustrate this effect, we analyze the changes from the current climate (1970-1999) to the mid 21st century (2030-2059). Changes in seasonal-mean temperature, precipitation, and snowpack are presented. Several climatological indices of extreme daily weather are also presented: precipitation intensity, fraction of precipitation occurring in extreme daily events, heat wave frequency, growing season length, and frequency of warm nights. Despite somewhat different changes in seasonal precipitation and temperature from the two regional simulations, consistent results for changes in snowpack and extreme precipitation are found in both simulations.

Salathe, E.; Leung, Lai-Yung R.; Qian, Yun; Zhang, Yongxin

2010-05-05T23:59:59.000Z

386

AtmosphericAtmospheric Composition Introduction The division investigates the atmospheric  

E-Print Network [OSTI]

development on observation side was the installation of an ozone observation station in Surinam in close co-operation with the Surinam Meteorological Service. Processes in the tropical regions are important for the global climate and the global atmospheric composition. The participation in Indoex (Indian Ocean Experiment) and this Surinam

Haak, Hein

387

Assessment of Molecular Modeling & Simulation  

SciTech Connect (OSTI)

This report reviews the development and applications of molecular and materials modeling in Europe and Japan in comparison to those in the United States. Topics covered include computational quantum chemistry, molecular simulations by molecular dynamics and Monte Carlo methods, mesoscale modeling of material domains, molecular-structure/macroscale property correlations like QSARs and QSPRs, and related information technologies like informatics and special-purpose molecular-modeling computers. The panel's findings include the following: The United States leads this field in many scientific areas. However, Canada has particular strengths in DFT methods and homogeneous catalysis; Europe in heterogeneous catalysis, mesoscale, and materials modeling; and Japan in materials modeling and special-purpose computing. Major government-industry initiatives are underway in Europe and Japan, notably in multi-scale materials modeling and in development of chemistry-capable ab-initio molecular dynamics codes.

None

2002-01-03T23:59:59.000Z

388

Measuring kinetic energy changes in the mesoscale with low acquisition rates  

SciTech Connect (OSTI)

We report on the measurement of the average kinetic energy changes in isothermal and non-isothermal quasistatic processes in the mesoscale, realized with a Brownian particle trapped with optical tweezers. Our estimation of the kinetic energy change allows to access to the full energetic description of the Brownian particle. Kinetic energy estimates are obtained from measurements of the mean square velocity of the trapped bead sampled at frequencies several orders of magnitude smaller than the momentum relaxation frequency. The velocity is tuned applying a noisy electric field that modulates the amplitude of the fluctuations of the position and velocity of the Brownian particle, whose motion is equivalent to that of a particle in a higher temperature reservoir. Additionally, we show that the dependence of the variance of the time-averaged velocity on the sampling frequency can be used to quantify properties of the electrophoretic mobility of a charged colloid. Our method could be applied to detect temperature gradients in inhomogeneous media and to characterize the complete thermodynamics of biological motors and of artificial micro and nanoscopic heat engines.

Roldn, . [ICFOInstitut de Cincies Fotniques, Mediterranean Technology Park, Av. Carl Friedrich Gauss 3, 08860 Castelldefels (Barcelona) (Spain); GISCGrupo Interdisciplinar de Sistemas Complejos, Madrid (Spain); Martnez, I. A.; Rica, R. A., E-mail: rul@ugr.es [ICFOInstitut de Cincies Fotniques, Mediterranean Technology Park, Av. Carl Friedrich Gauss 3, 08860 Castelldefels (Barcelona) (Spain); Dinis, L. [GISCGrupo Interdisciplinar de Sistemas Complejos, Madrid (Spain); Departamento de Fsica Atmica, Molecular y Nuclear, Universidad Complutense de Madrid, 28040 Madrid (Spain)

2014-06-09T23:59:59.000Z

389

Impact of mesoscale eddies on water transport between the Pacific Ocean and the Bering Sea  

E-Print Network [OSTI]

Sea surface height anomalies observed by satellites in 1993--2012 are combined with simulation and observations by surface drifters and Argo floats to study water flow pattern in the Near Strait (NS) connected the Pacific Ocean with the Bering Sea. Daily Lagrangian latitudinal maps, computed with the AVISO surface velocity field, and calculation of the transport across the strait show that the flow through the NS is highly variable and controlled by mesoscale and submesoscale eddies in the area. On the seasonal scale, the flux through the western part of the NR is negatively correlated with the flux through its eastern part ($r=-0.93$). On the interannual time scale, a significant positive correlation ($r=0.72$) is diagnosed between the NS transport and the wind stress in winter. Increased southward component of the wind stress decreases the northward water transport through the strait. Positive wind stress curl over the strait area in winter--spring generates the cyclonic circulation and thereby enhances the...

Prants, S V; Budyansky, M V; Uleysky, M Yu

2013-01-01T23:59:59.000Z

390

atmospheric emitted radiance: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

mesoscales (wavelengths of 64-957 km) were obtained potential energy by differential solar heating. This is converted to eddy available potential energy 11 The horizontal...

391

Atmospheric Neutrino Fluxes  

E-Print Network [OSTI]

Starting with an historical review, I summarize the status of calculations of the flux of atmospheric neutrinos and how they compare to measurements.

Thomas K. Gaisser

2005-02-18T23:59:59.000Z

392

Origin of the Springtime Westerly Bias in Equatorial Atlantic Surface Winds in the Community Atmosphere Model Version 3 (CAM3) Simulation  

E-Print Network [OSTI]

­atmosphere interaction generally rules. 1. Introduction Trade winds (easterlies) prevail over most of the tropical in the cen- tral and eastern basins, and vice versa. Along the equa- tor, easterly winds generate equatorialOrigin of the Springtime Westerly Bias in Equatorial Atlantic Surface Winds in the Community

Nigam, Sumant

393

Atmospheric Carbon Dioxide Variability in the Community Earth System Model: Evaluation and Transient Dynamics during the Twentieth and Twenty-First Centuries  

E-Print Network [OSTI]

predictions from CMIP5 Earth system models and comparisonin the Community Earth System Model: Evaluation andusing the Community Earth System ModelBiogeochemistry (

2013-01-01T23:59:59.000Z

394

MERCURY IN THE ATMOSPHERE, BIOSPHERE, AND POLICY SPHERE  

E-Print Network [OSTI]

MERCURY IN THE ATMOSPHERE, BIOSPHERE, AND POLICY SPHERE: Insights from global modeling Noelle Atmospheric Chemistry Program #12;FROM ATMOSPHERE TO FISH: MERCURY RISING Ice core from Wyoming [Schuster et al., ES&T 2002] Mercury deposition has increased by 300% since industrialization Major anthropogenic

Selin, Noelle Eckley

395

A correlated K-distribution model of the heating rates for H[sub 2]O and a molecular mixture in the 0-2500 cm[sup [minus]1] wavelength region in the atmosphere between 0 and 60 km  

SciTech Connect (OSTI)

For this report a prototype infrared radiative transfer model using a correlated k-distribution technique to calculate the transmission between atmospheric levels has been used to calculate the radiative fluxes and heating rates for H[sub 2]O and a mixture of the major molecular absorbers in the atmosphere between 0 and 60 km. The mixture consists of H[sub 2]O, CO[sub 2], O[sub 3], CH[sub 4], and N[sub 2]O. The wave number range considered is 0-2500 cm[sup [minus]1]. The use of the k-distribution method allows 25 cm[sup [minus]1] wave number bins to produce fluxes and heating rates which are within ten percent of the results of detailed line by line calculations.

Grossman, A S; Grant, K E

1992-11-16T23:59:59.000Z

396

Atmospheric Thermodynamics Composition  

E-Print Network [OSTI]

1 Atmospheric Thermodynamics Ch1 Composition Ch2 Laws Ch3 Transfers Ch12 EnergyBalance Ch4 Water Ch Sciences: Atmospheric Thermodynamics Instructor: Lynn Russell, NH343 http #12;2 Review from Ch. 1 Thermodynamic quantities Composition Pressure Density Temperature

Russell, Lynn

397

Atmospheric Dynamics II Instructor  

E-Print Network [OSTI]

AT602 Atmospheric Dynamics II 2 credits Instructor: David W. J. Thompson davet: An Introduction to Dynamic Meteorology, 5th Edition, Academic Press (recommended) · Marshall, J., and Plumb, R. A., 2008: Atmosphere, Ocean, and Climate Dynamics: An Introductory Text, Academic Press. · Vallis, G. K

398

Assessing Seasonal Transport and Deposition of Agricultural Emissions in Eastern North Carolina, U.S.A.  

E-Print Network [OSTI]

the variability and uncertainty in the regional pollutant transport. Key words: Air pollution, atmospheric values obtained using an air pollution transport and dispersion model. This mesoscale information Carolina. Results show that highly variable seasonal and diurnal atmospheric circulations characterize

Raman, Sethu

399

Observational Analysis of the Predictability of Mesoscale Convective Systems ISRAEL L. JIRAK AND WILLIAM R. COTTON  

E-Print Network [OSTI]

AND WILLIAM R. COTTON Department of Atmospheric Science, Colorado State University, Fort Collins, Colorado merge into a large, long-lived organized convective system (Cotton and Anthes 1989). Thus, forecasting

400

E-Print Network 3.0 - atmospherically deposited radionuclides...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

7 Be in rainwater. Atmospheric inputs of the radionuclides to Cumbria (UK) were recorded. Rainwater... ; lakes; radionuclide; deposition; history; modelling. Reference ... Source:...

Note: This page contains sample records for the topic "atmospheric mesoscale model" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

On the effect of the steady-state approximation in time-space composite studies of mesoscale convective systems  

E-Print Network [OSTI]

ON THE EFFECT OF THE STRA 'Y-STATE APPROXIMATION IN TIME-SPACE COMPOSITE STUDIES OF MESOSCALE CONVECTIVE SYSTEMS A Thesis KEVIN MORGAN MATTISON Subnitted to the Office of Graduate Studies of Texas A&M University in partial fulfillnent... of the requirements for the degree of MASTER OF SCIENCE Decenber 1992 Major Subject: Meteorology ON THE EFFECT OF THE STEADY-STATE APPROXINATIOH IN TIME-SPACE COMPOSITE STUDIES OF NESOSCALE COHVECTIVE SYSTENS A Thesis KEVIN MORGAN NATTISOH Approved as to style...

Mattison, Kevin Morgan

1992-01-01T23:59:59.000Z

402

Risk assessment for the Waste Technologies Industries (WTI) hazardous waste incineration facility (East Liverpool, Ohio). Volume 4. Atmospheric dispersion and deposition modeling of emissions  

SciTech Connect (OSTI)

Contents: Introduction; Technical Description of ISC-COMPDEP; Modeling Input Parameters; Discussion of Modeling Results; Summary and Major Assumptions; and References.

NONE

1997-05-01T23:59:59.000Z

403

Reconciling estimates of the contemporary North American carbon balance among terrestrial biosphere models, atmospheric inversions and a new approach for estimating net ecosystem exchange from inventory-based data  

SciTech Connect (OSTI)

We develop an approach for estimating net ecosystem exchange (NEE) using inventory-based information over North America (NA) for a recent 7-year period (ca. 2000 2006). The approach notably retains information on the spatial distribution of NEE, or the vertical exchange between land and atmosphere of all non-fossil fuel sources and sinks of CO2, while accounting for lateral transfers of forest and crop products as well as their eventual emissions. The total NEE estimate of a 327 252 TgC yr1 sink for NA was driven primarily by CO2 uptake in the Forest Lands sector (248 TgC yr1), largely in the Northwest and Southeast regions of the US, and in the Crop Lands sector (297 TgC yr1), predominantly in the Midwest US states. These sinks are counteracted by the carbon source estimated for the Other Lands sector (+218 TgC yr1), where much of the forest and crop products are assumed to be returned to the atmosphere (through livestock and human consumption). The ecosystems of Mexico are estimated tobe a small net source (+18 TgC yr1) due to land use change between 1993 and 2002. We compare these inventorybased estimates with results from a suite of terrestrial biosphere and atmospheric inversion models, where the mean continental-scale NEE estimate for each ensemble is 511 TgC yr1 and 931 TgC yr1, respectively. In the modeling approaches, all sectors, including Other Lands, were generally estimated to be a carbon sink, driven in part by assumed CO2 fertilization and/or lack of consideration of carbon sources from disturbances and product emissions. Additional fluxes not measured by the inventories, although highly uncertain, could add an additional 239 TgC yr1 to the inventory-based NA sink estimate, thus suggesting some convergence with the modeling approaches.

Hayes, Daniel J [ORNL; Turner, David P [Oregon State University, Corvallis; Stinson, Graham [Pacific Forestry Centre, Canadian Forest Service; Mcguire, David [University of Alaska; Wei, Yaxing [ORNL; West, Tristram O. [Joint Global Change Research Institute, PNNL; Heath, Linda S. [USDA Forest Service; De Jong, Bernardus [ECOSUR; McConkey, Brian G. [Agriculture and Agri-Food Canada; Birdsey, Richard A. [U.S. Department of Agriculture Forest Service; Kurz, Werner [Canadian Forest Service; Jacobson, Andrew [NOAA ESRL and CIRES; Huntzinger, Deborah [University of Michigan; Pan, Yude [U.S. Department of Agriculture Forest Service; Post, Wilfred M [ORNL; Cook, Robert B [ORNL

2012-01-01T23:59:59.000Z

404

Our scenario is akin to the magnetic furnace model proposed by Axford and  

E-Print Network [OSTI]

Our scenario is akin to the magnetic furnace model proposed by Axford and McKenzie (14­16) and to ideas invoking reconnection of mesoscale loops (38, 39). We adopt from the furnace model the idea. However, our model of the nascent solar wind is intrinsically 3-D, and the magnetic field geometry

Pe'er, Dana

405

An integrated model for the post-solidification shape and grain morphology of fusion welds  

E-Print Network [OSTI]

Through an integrated macroscale/mesoscale computational model, we investigate the developing shape and grain morphology during the melting and solidification of a weld. In addition to macroscale surface tension driven fluid flow and heat transfer, we predict the solidification progression using a mesoscale model accounting for realistic solidification kinetics, rather than quasi-equilibrium thermodynamics. The tight coupling between the macroscale and the mesoscale distinguishes our results from previously published studies. The inclusion of Marangoni driven fluid flow and heat transfer, both during heating and cooling, was found to be crucial for accurately predicting both weld pool shape and grain morphology. However, if only the shape of the weld pool is of interest, a thermodynamic quasi-equilibrium solidification model, neglecting solidification kinetics, was found to suffice when including fluid flow and heat transfer. We demonstrate that the addition of a sufficient concentration of approximately 1 $\\...

Kidess, Anton; Duggan, Gregory; Browne, David J; Kenjere, Saa; Richardson, Ian; Kleijn, Chris R

2015-01-01T23:59:59.000Z

406

Mesoscale Surface Pressure and Temperature Features Associated with Bow Echoes REBECCA D. ADAMS-SELIN AND RICHARD H. JOHNSON  

E-Print Network [OSTI]

-SELIN AND RICHARD H. JOHNSON Department of Atmospheric Science, Colorado State University, Fort Collins, Colorado

Johnson, Richard H.

407

E-Print Network 3.0 - atmospheric mercury concentrations Sample...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

et al. 2007... 1 Global 3-D land-ocean-atmosphere model for mercury: present-day vs. pre-industrial1 cycles... 12 13 14 15 Short title: Global 3-D land-ocean-atmosphere model ......

408

E-Print Network 3.0 - atmospheric layers Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

layer model Summary: an atmosphere, using the layer model, which incorporates the greenhouse effect of the atmosphere. For now... ,atm + Idown,atm Iup, ground If radiation up and...

409

Three-dimensional hydrodynamical CO5BOLD model atmospheres of red giant stars. IV. Oxygen diagnostics in extremely metal-poor red giants with infrared OH lines  

E-Print Network [OSTI]

Context. Although oxygen is an important tracer of Galactic chemical evolution, measurements of its abundance in the atmospheres of the oldest Galactic stars are still scarce and rather imprecise. At the lowest end of the metallicity scale, oxygen can only be measured in giant stars and in most of cases such measurements rely on a single forbidden [O I] 630 nm line that is very weak and frequently blended with telluric lines. Although molecular OH lines located in the ultraviolet and infrared could also be used for the diagnostics, oxygen abundances obtained from the OH lines and the [O I] 630 nm line are usually discrepant to a level of ~0.3-0.4 dex. Aims. We study the influence of convection on the formation of the infrared (IR) OH lines and the forbidden [O I] 630 nm line in the atmospheres of extremely metal-poor (EMP) red giant stars. Methods. We used high-resolution and high signal-to-noise ratio spectra of four EMP red giant stars obtained with the VLT CRIRES spectrograph. For each EMP star, 4-14 IR OH...

Dobrovolskas, V; Bonifacio, P; Caffau, E; Ludwig, H -G; Steffen, M; Spite, M

2015-01-01T23:59:59.000Z

410

Simulated Atmospheric Deposition of Pollutants into Watersheds in the Pacific Northwest  

E-Print Network [OSTI]

A biosphere relevant earth system model (BioEaSM) is needed to integrate features of atmospheric, terrestrial

Collins, Gary S.

411

Atmospheric Carbon Dioxide Variability in the Community Earth System Model: Evaluation and Transient Dynamics during the Twentieth and Twenty-First Centuries  

E-Print Network [OSTI]

Arora, V. K. , and A. Montenegro, 2011: Small temperatureet al. 2009; Arora and Montenegro 2011). These models allow

2013-01-01T23:59:59.000Z

412

The porous atmosphere of eta Carinae  

E-Print Network [OSTI]

We analyze the wind generated by the great 20 year long super-Eddington outburst of eta-Carinae. We show that using classical stellar atmospheres and winds theory, it is impossible to construct a consistent wind model in which a sufficiently small amount of mass, like the one observed, is shed. One expects the super-Eddington luminosity to drive a thick wind with a mass loss rate substantially higher than the observed one. The easiest way to resolve the inconsistency is if we alleviate the implicit notion that atmospheres are homogeneous. An inhomogeneous atmosphere, or "porous", allows more radiation to escape while exerting a smaller average force. Consequently, such an atmosphere yields a considerably lower mass loss rate for the same total luminosity. Moreover, all the applications of the Eddington Luminosity as a strict luminosity limit should be revised, or at least reanalyzed carefully.

Nir J. Shaviv

2000-02-09T23:59:59.000Z

413

REVIEWS OF GEOPHYSICS: U.S. NATIONAL REPORT TO INTERNATIONAL UNION OF GEODESY AND GEOPHYSICS COOL SEASON CYCLOGENESIS AND ASSOCIATED MESOSCALE WEATHER  

E-Print Network [OSTI]

technological advances in our ability to forecast cyclogenesis, one cannot say that the cyclone problem to probe the mesoscale structure and evolution of winter cyclones in recent years. Many recent advances treatment of their dynamics. Kraus and Businger (1994) review the air-sea interaction in cyclones, and Houze

Businger, Steven

414

Behavior of buoyant moist plumes in turbulent atmospheres  

E-Print Network [OSTI]

A widely applicable computational model of buoyant moist plumes in turbulent atmospheres has been constructed. To achieve this a one dimensional Planetary Boundary Layer (P.B.L.) model has been developed to account for ...

Hamza, Redouane

1981-01-01T23:59:59.000Z

415

Uncertainty in Greenhouse Emissions and Costs of Atmospheric Stabilization  

E-Print Network [OSTI]

We explore the uncertainty in projections of emissions, and costs of atmospheric stabilization applying the MIT Emissions Prediction and Policy Analysis model, a computable general equilibrium model of the global economy. ...

Webster, Mort D.

416

Atmospheric Dispersion Lecture Atmospheric Local-Scale Dispersion Modelling.  

E-Print Network [OSTI]

heterogeneous temperature and pressure fields. Local heat flux depends on the position of the point to the sun-resting global circulation of air masses is the unequal distribution of solar heat flux to the earth surface). The temperature depends on the heat transfer and capacity characteristics of the surface (sea, soil, desert

417

Risk assessment for the Waste Technologies Industries (WTI) hazardous waste incinerator facility (east Liverpool, Ohio). Volume 4. Atmospheric dispersion and deposition modeling of emissions. Draft report  

SciTech Connect (OSTI)

The report constitutes a comprehensive site-specific risk assessment for the WTI incineration facility located in East Liverpool, OH. Volume IV describes the air dispersion model used to estimate air concentrations and particle deposition, as well as the results of the modeling exercise.

NONE

1995-11-01T23:59:59.000Z

418

GFDL ARM Project Technical Report: Using ARM Observations to Evaluate Cloud and Convection Parameterizations & Cloud-Convection-Radiation Interactions in the GFDL Atmospheric General Circulation Model  

SciTech Connect (OSTI)

This report briefly summarizes the progress made by ARM postdoctoral fellow, Yanluan Lin, at GFDL during the period from October 2008 to present. Several ARM datasets have been used for GFDL model evaluation, understanding, and improvement. This includes a new ice fall speed parameterization with riming impact and its test in GFDL AM3, evaluation of model cloud and radiation diurnal and seasonal variation using ARM CMBE data, model ice water content evaluation using ARM cirrus data, and coordination of the TWPICE global model intercomparison. The work illustrates the potential and importance of ARM data for GCM evaluation, understanding, and ultimately, improvement of GCM cloud and radiation parameterizations. Future work includes evaluation and improvement of the new dynamicsPDF cloud scheme and aerosol activation in the GFDL model.

V. Ramaswamy; L. J. Donner; J-C. Golaz; S. A. Klein

2010-06-17T23:59:59.000Z

419

Dynamics of Atmospheres  

E-Print Network [OSTI]

transfer ­ Solar heating of surface, and atmosphere via dust absorption ­ Infrared CO2 band cooling (especially around 667 cm-1) ­ nonLTE near-infrared heating of CO2 and nonLTE cooling effects above ~60-80 km. Baroclinic waves, scales, heat and momentum transport, seasonal occurrence. Qualitative treatment

Read, Peter L.

420

Dynamics of Planetary Atmospheres  

E-Print Network [OSTI]

pressure (bars) N2 82%; Ar 12%; CH4 6%CO2 96.5%; N2 3.5%Atmospheric composition 26177Orbital inclination (1992) orbiter ­ Winds from cloud-tracking and probe drifts ­ IR temperatures, solar-fixed tides, polar-Huygens mission (from 2005) ­ Doppler wind descent profile ­ IR temperature and composition maps ­ Visible, IR

Read, Peter L.

Note: This page contains sample records for the topic "atmospheric mesoscale model" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Application of the HGSYSTEM/UF{sub 6} model to simulate atmospheric dispersion of UF{sub 6} releases from uranium enrichment plants  

SciTech Connect (OSTI)

Uranium hexafluoride is a dense, reactive gas used in Gaseous Diffusion Plants (GDPs) to make uranium enriched in the {sup 235}U isotope. Large quantities of UF{sub 6} exist at the GDPs in the form of in-process gas and as a solid in storage cylinders; smaller amounts exist as hot liquid during transfer operations. If liquid UF{sub 6} is released to the environment, it immediately flashes to a solid and a dense gas that reacts rapidly with water vapor in the air to form solid particles of uranyl fluoride and hydrogen fluoride gas. Preliminary analyses were done on various accidental release scenarios to determine which scenarios must be considered in the safety analyses for the GDPS. These scenarios included gas releases due to failure of process equipment and liquid/gas releases resulting from a breach of transfer piping from a cylinder. A major goal of the calculations was to estimate the response time for mitigating actions in order to limit potential off-site consequences of these postulated releases. The HGSYSTEM/UF{sub 6} code was used to assess the consequences of these release scenarios. Inputs were developed from release calculations which included two-phase, choked flow followed by expansion to atmospheric pressure. Adjustments were made to account for variable release rates and multiple release points. Superpositioning of outputs and adjustments for exposure time were required to evaluate consequences based on health effects due to exposures to uranium and HF at a specific location.

Goode, W.D. Jr.; Bloom, S.G.; Keith, K.D. Jr.

1995-03-01T23:59:59.000Z

422

Future climate trends from a first-difference atmospheric carbon dioxide regression model involving emissions scenarios for business as usual and for peak fossil fuel  

E-Print Network [OSTI]

This paper investigates the implications of the future continuation of the demonstrated past (1960-2012) strong correlation between first-difference atmospheric CO2 and global surface temperature. It does this, for the period from the present to 2050, for a comprehensive range of future global fossil fuel energy use scenarios. The results show that even for a business-as-usual (the mid-level IPCC) fossil fuel use estimate, global surface temperature will rise at a slower rate than for the recent period 1960-2000. Concerning peak fossil fuel, for the most common scenario the currently observed (1998-2013)temperature plateau will turn into a decrease. The observed trend to date for temperature is compared with that for global climate disasters: these peaked in 2005 and are notably decreasing. The temperature and disaster results taken together are consistent with either a reduced business-as-usual fossil fuel use scenario into the future, or a peak fossil fuel scenario, but not with the standard business-as-usu...

Leggett, L M W

2014-01-01T23:59:59.000Z

423

Carbonaceous spheresan unusual template for solid metal oxide mesoscale spheres: Application to ZnO spheres  

SciTech Connect (OSTI)

A green template route for the synthesis of mesoscale solid ZnO spheres was ascertained. The protocol involves a double coating of the carbonaceous spheres with successive layers of zinc-containing species by alternating a non-ultrasound and ultrasound-assisted deposition, followed by calcination treatments. The composites were characterized by FTIR spectroscopy, thermal analysis, scanning electron microscopy while the obtained ZnO spheres by X-ray diffraction, Raman spectroscopy, scanning and transmission electron microscopy, N{sub 2} adsorptiondesorption isotherms and photoluminescence investigations. A growth mechanism of the solid spheres is advanced based on these results. While the spheres' diameters and the mean size values of ZnO are independent on deposition order, the surface area and the external porosity are fairly dependent. The photoluminescence measurements showed interesting emission features, with emission bands in the violet to orange region. The spheres present high photocatalytical activity towards the degradation of phenol under UV irradiation, the main reaction being its mineralization. - Graphical abstract: A novel and eco-friendly methodology for the synthesis of mesoscale solid ZnO spheres was developed. The protocol involves a double coating of the starch-derived carbonaceous spheres with successive layers of zinc-containing species by alternating a non-ultrasound and ultrasound-assisted deposition, followed by calcination treatments. - Highlights: ZnO solid spheres are obtained via a template route using carbonaceous spheres. Two-step coatings of interchangeable order are used as deposition procedure. The coating procedure influences the porosity and surface area. ZnO spheres exhibited interesting visible photoluminescence properties. Solid spheres showed photocatalytical activity in degradation of phenol.

Patrinoiu, Greta; Caldern-Moreno, Jose Maria; Culita, Daniela C. [Illie Murgulescu Institute of Physical Chemistry, Romanian Academy, Splaiul Independentei 202, 060021 Bucharest (Romania); Birjega, Ruxandra [National Institute for Lasers, Plasma and Radiation Physics, P.O. Box Mg27, Magurele, Bucharest (Romania); Ene, Ramona [Ilie Murgulescu Institute of Physical Chemistry, Romanian Academy, Splaiul Independentei 202, 060021 Bucharest (Romania); Carp, Oana, E-mail: ocarp@icf.ro [Ilie Murgulescu Institute of Physical Chemistry, Romanian Academy, Splaiul Independentei 202, 060021 Bucharest (Romania)

2013-06-15T23:59:59.000Z

424

Methane Fluxes Between Terrestrial Ecosystems and the Atmosphere at Northern High Latitudes During the Past Century: A retrospective analysis with a process-based biogeochemistry model  

E-Print Network [OSTI]

We develop and use a new version of the Terrestrial Ecosystem Model (TEM) to study how rates of methane (CH4) emissions and consumption in high-latitude soils of the Northern Hemisphere have changed over the past century ...

Zhuang, Qianlai.

425

E-Print Network 3.0 - atmosphere control systems Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

coupling software Summary: linking the main model components of present-day Earth System models (ESMs), i.e. the atmosphere... the framework to build and control a...

426

Atmospheric Data Package for the Composite Analysis  

SciTech Connect (OSTI)

The purpose of this data package is to summarize our conceptual understanding of atmospheric transport and deposition, describe how this understanding will be simplified for numerical simulation as part of the Composite Analysis (i.e., implementation model), and finally to provide the input parameters needed for the simulations.

Napier, Bruce A.; Ramsdell, James V.

2005-09-01T23:59:59.000Z

427

Propagation of strangelets in the Earth's atmosphere  

E-Print Network [OSTI]

A new model for the description of the behaviour of strangelets in the Earth's atmosphere is presented. Strangelet fission induced by collision with air nuclei is included. It is shown that strangelets with certain parameters of initial mass and energy may reach depths near sea level, which can be examined by ground-based experiments.

Fei Wu; Ren-Xin Xu; Bo-Qiang Ma

2007-02-13T23:59:59.000Z

428

JournalofGeophysicalResearch: Atmospheres RESEARCH ARTICLE  

E-Print Network [OSTI]

convection to start from more levels Simple modification of convective parameterization Correspondence to of the Community Atmosphere Model (CAM4), we show that the overall accuracy in the diurnal simulation of convective rise to diurnal cycles in cloud amount [May et al., 2012] and relative humidity [Soden, 2000] which

Folkins, Ian

429

SLAC Mesoscale Integrated Biology Pilot Project: MFX Station at LCLS | U.S.  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 -the Mid-Infrared0 ResourceAwards SAGE Awards ,# ,SchoolsNEUTRINOSIS

430

Impact of aerosol on mixed-phase stratocumulus during MPACE in a mesoscale  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation ProposedUsingFun withconfinementEtching. |EndecahemeEMSLImaging the BrainIcePointImpact

431

Mesoscale Origin of the Enhanced Cycling-Stability of the Si-Conductive  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment Surfaces andMapping theEnergy Storage EnergyLaboratory Mesopourous blockPolymer

432

Center for Mesoscale Transport Properties (m2M) | U.S. DOE Office of  

Office of Science (SC) Website

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched5 IndustrialIsadore Perlman,Bios High Energy PhysicsU.S. DOE Office ofof

433

Differential atmospheric tritium sampler  

DOE Patents [OSTI]

An atmospheric tritium sampler is provided which uses a carrier gas comprised of hydrogen gas and a diluting gas, mixed in a nonexplosive concentration. Sample air and carrier gas are drawn into and mixed in a manifold. A regulator meters the carrier gas flow to the manifold. The air sample/carrier gas mixture is pulled through a first moisture trap which adsorbs water from the air sample. The moisture then passes through a combustion chamber where hydrogen gas in the form of H/sub 2/ or HT is combusted into water. The manufactured water is transported by the air stream to a second moisture trap where it is adsorbed. The air is then discharged back into the atmosphere by means of a pump.

Griesbach, O.A.; Stencel, J.R.

1987-10-02T23:59:59.000Z

434

Differential atmospheric tritium sampler  

DOE Patents [OSTI]

An atmospheric tritium sampler is provided which uses a carrier gas comprised of hydrogen gas and a diluting gas, mixed in a nonexplosive concentration. Sample air and carrier gas are drawn into and mixed in a manifold. A regulator meters the carrier gas flow to the manifold. The air sample/carrier gas mixture is pulled through a first moisture trap which adsorbs water from the air sample. The mixture then passes through a combustion chamber where hydrogen gas in the form of H.sub.2 or HT is combusted into water. The manufactured water is transported by the air stream to a second moisture trap where it is adsorbed. The air is then discharged back into the atmosphere by means of a pump.

Griesbach, Otto A. (Langhorne, PA); Stencel, Joseph R. (Skillman, NJ)

1990-01-01T23:59:59.000Z

435

The changing atmosphere  

SciTech Connect (OSTI)

The chemistry of the atmosphere is changing, in large measure because of gases emitted by such human activities as farming, manufacturing, and the combustion of fossil fuels. The deleterious effects are increasingly evident; they may well become worse in the years ahead. This paper discusses the pollutants and the environmental perturbations with which they are associated. The authors believe the solution to the earth's environmental problems lies in a truly global effort.

Graedel, T.E.; Crutzen, P.J.

1989-09-01T23:59:59.000Z

436

Environmental Chemistry II (Atmospheric Chemistry)  

E-Print Network [OSTI]

Seinfeld, J. H. and Pandis, S. N. Atmospheric Chemistry and Physics: From Air Pollution to Climate ChangeSYLLABUS FOR Environmental Chemistry II (Atmospheric Chemistry) FCH 511 Fall 2013 Theodore S

Dibble, Theodore

437

Nitrogen trifluoride global emissions estimated from updated atmospheric measurements  

E-Print Network [OSTI]

Nitrogen trifluoride global emissions estimated from updated atmospheric measurements Tim Arnolda,1's radiative budget; however, our understand- ing of its atmospheric burden and emission rates has been limited together with an atmo- spheric model and inverse method, we estimate that the global emissions of NF3

Severinghaus, Jeffrey P.

438

A Field Experiment to Validate Atmospheric Dispersion and  

E-Print Network [OSTI]

Rise-R.495 A Field Experiment to Validate Atmospheric Dispersion and Dose Models S. P. Nielsen* S Roskilde, Denmark May 1986 #12;RIS?-R-495 DOUBLE TRACER EXPERIMENTS TO EVALUATE ATMOSPHERIC TRANSPORT Pollution Laboratory, Risø National Laboratory, DK-4000 Roskilde, Denmark Abstract. Two tracers

439

Engineering Identifying the source of an atmospheric pollutant  

E-Print Network [OSTI]

Chemical Engineering Abstract Identifying the source of an atmospheric pollutant or phenomena this question using combinations of atmospheric models and remote sensing observations will be presented challenge currently facing the US EPA in developing secondary standards for the control of this pollutant

440

Atmospheric response to solar radiation absorbed by phytoplankton  

E-Print Network [OSTI]

Atmospheric response to solar radiation absorbed by phytoplankton K. M. Shell and R. Frouin Scripps the absorption of solar radiation, affecting upper ocean temperature and circulation. These changes, in turn: phytoplankton, atmospheric general circulation model (AGCM), absorption of solar radiation, seasonal cycle, sea

Shell, Karen M.

Note: This page contains sample records for the topic "atmospheric mesoscale model" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Atmospheric dispersion in mountain valleys and basins  

SciTech Connect (OSTI)

The primary goal of the research is to further characterize and understand dispersion in valley and basin atmospheres. A secondary, and related goal, is to identify and understand the dominant physical processes governing this dispersion. This has been accomplished through a review of the current literature, and analyses of recently collected data from two field experiments. This work should contribute to an improved understanding of material transport in the atmospheric boundary layer. It was found that dispersion in a freely draining valley (Brush Creek valley, CO) atmosphere is much greater than in an enclosed basin (Roanoke, VA) atmosphere primarily because of the greater wind speeds moving past the release point and the greater turbulence levels. The development of a cold air pool in the Roanoke basin is the dominant process governing nighttime dispersion in the basin, while the nighttime dispersion in the Brush Creek valley is dominated by turbulent diffusion and plume confinement between the valley sidewalls. The interaction between valley flows and above ridgetops flows is investigated. A ventilation rate'' of material transport between the valley and above ridgetop flows is determined. This is important in regional air pollution modeling and global climate modeling. A simple model of dispersion in valleys, applicable through a diurnal cycle, is proposed.

Allwine, K.J.

1992-01-01T23:59:59.000Z

442

Atmospheric dispersion in mountain valleys and basins  

SciTech Connect (OSTI)

The primary goal of the research is to further characterize and understand dispersion in valley and basin atmospheres. A secondary, and related goal, is to identify and understand the dominant physical processes governing this dispersion. This has been accomplished through a review of the current literature, and analyses of recently collected data from two field experiments. This work should contribute to an improved understanding of material transport in the atmospheric boundary layer. It was found that dispersion in a freely draining valley (Brush Creek valley, CO) atmosphere is much greater than in an enclosed basin (Roanoke, VA) atmosphere primarily because of the greater wind speeds moving past the release point and the greater turbulence levels. The development of a cold air pool in the Roanoke basin is the dominant process governing nighttime dispersion in the basin, while the nighttime dispersion in the Brush Creek valley is dominated by turbulent diffusion and plume confinement between the valley sidewalls. The interaction between valley flows and above ridgetops flows is investigated. A ``ventilation rate`` of material transport between the valley and above ridgetop flows is determined. This is important in regional air pollution modeling and global climate modeling. A simple model of dispersion in valleys, applicable through a diurnal cycle, is proposed.

Allwine, K.J.

1992-01-01T23:59:59.000Z

443

Interactions Among Emissions, Atmospheric Chemistry, and Climate Change: Implications for Future Trends  

E-Print Network [OSTI]

Interactions Among Emissions, Atmospheric Chemistry, and Climate Change: Implications for Future emissions, atmospheric chemistry, and climate, we have conducted a series of simulations on 120-year time emissions and different assumptions for chemistry and climate model parameters. To specifically identify

444

Harmonic propagation of variability in surface energy balance within a coupled soil-vegetation-atmosphere system  

E-Print Network [OSTI]

[1] The response of a soil-vegetation-atmosphere continuum model to incoming radiation forcing is investigated in order to gain insights into the coupling of soil and atmospheric boundary layer (ABL) states and fluxes. The ...

Gentine, P.

445

E-Print Network 3.0 - atmospheric pressure interface Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

354, 621628 (2004) doi:10.1111j.1365-2966.2004.08223.x Correlation of atmospheric opacity measurements by SCUBA Summary: -ground, location-specific atmospheric models. ULTRAM...

446

E-Print Network 3.0 - atmospheric visualization collection Sample...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

354, 621628 (2004) doi:10.1111j.1365-2966.2004.08223.x Correlation of atmospheric opacity measurements by SCUBA Summary: -ground, location-specific atmospheric models. ULTRAM...

447

Explorations of AtmosphereOceanIce Climates on an Aquaplanet and Their Meridional Energy Transports  

E-Print Network [OSTI]

The degree to which total meridional heat transport is sensitive to the details of its atmospheric and oceanic components is explored. A coupled atmosphere, ocean, and sea ice model of an aquaplanet is employed to simulate ...

Marshall, John C.

448

Final Report for Integrated Multiscale Modeling of Molecular Computing Devices  

SciTech Connect (OSTI)

In collaboration with researchers at Vanderbilt University, North Carolina State University, Princeton and Oakridge National Laboratory we developed multiscale modeling and simulation methods capable of modeling the synthesis, assembly, and operation of molecular electronics devices. Our role in this project included the development of coarse-grained molecular and mesoscale models and simulation methods capable of simulating the assembly of millions of organic conducting molecules and other molecular components into nanowires, crossbars, and other organized patterns.

Glotzer, Sharon C.

2013-08-28T23:59:59.000Z

449

Atmospheric Aerosol Systems | EMSL  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May Jun Jul(Summary)morphinanInformation InInformationCenterResearch HighlightsTools PrintableCARIBU ProposalBeamAtmospheric

450

Atmospheric Radiation Measurement Program  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)ProductssondeadjustsondeadjustAbout theOFFICEAmesApplication2ArgonneAssemblyDemandPlasma4August 1999 ARM

451

Atmospheric Radiation Measurement Program  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)ProductssondeadjustsondeadjustAbout theOFFICEAmesApplication2ArgonneAssemblyDemandPlasma4August 1999

452

Atmospheric Radiation Measurement Program  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)ProductssondeadjustsondeadjustAbout theOFFICEAmesApplication2ArgonneAssemblyDemandPlasma4August 1999July

453

Atmospheric Radiation Measurement Program  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)ProductssondeadjustsondeadjustAbout theOFFICEAmesApplication2ArgonneAssemblyDemandPlasma4August

454

Atmospheric Radiation Measurement Program  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth (AOD)ProductssondeadjustsondeadjustAbout theOFFICEAmesApplication2ArgonneAssemblyDemandPlasma4August3 ARM 2003

455

Atmospheric Particulates | EMSL  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc DocumentationP-Series to someone byDear Friend,Arthur J. Nozik -GrownAn overheadAtmospheric

456

Tropical atmosphere - Ocean interactions in a conceptual framework  

E-Print Network [OSTI]

Statistical analysis of observations (including atmospheric reanalysis and forced ocean model simulations) is used to address two questions: First, does an analogous mechanism to that of El NioSouthern Oscillation (ENSO) ...

Jansen, Malte Friedrich

457

Atmospheric Radiation Measurement Program Science Plan  

SciTech Connect (OSTI)

The Atmospheric Radiation Measurement (ARM) Program has matured into one of the key programs in the U.S. Climate Change Science Program. The ARM Program has achieved considerable scientific success in a broad range of activities, including site and instrument development, atmospheric radiative transfer, aerosol science, determination of cloud properties, cloud modeling, and cloud parameterization testing and development. The focus of ARM science has naturally shifted during the last few years to an increasing emphasis on modeling and parameterization studies to take advantage of the long time series of data now available. During the next 5 years, the principal focus of the ARM science program will be to: Maintain the data record at the fixed ARM sites for at least the next five years. Improve significantly our understanding of and ability to parameterize the 3-D cloud-radiation problem at scales from the local atmospheric column to the global climate model (GCM) grid square. Continue developing techniques to retrieve the properties of all clouds, with a special focus on ice clouds and mixed-phase clouds. Develop a focused research effort on the indirect aerosol problem that spans observations, physical models, and climate model parameterizations. Implement and evaluate an operational methodology to calculate broad-band heating rates in the atmospheric columns at the ARM sites. Develop and implement methodologies to use ARM data more effectively to test atmospheric models, both at the cloud-resolving model scale and the GCM scale. Use these methodologies to diagnose cloud parameterization performance and then refine these parameterizations to improve the accuracy of climate model simulations. In addition, the ARM Program is actively developing a new ARM Mobile Facility (AMF) that will be available for short deployments (several months to a year or more) in climatically important regions. The AMF will have much of the same instrumentation as the remote facilities at ARM's Tropical Western Pacific and the North Slope of Alaska sites. Over time, this new facility will extend ARM science to a much broader range of conditions for model testing.

Ackerman, T

2004-10-31T23:59:59.000Z

458

NEGLECTED CLOUDS IN T AND Y DWARF ATMOSPHERES  

SciTech Connect (OSTI)

As brown dwarfs cool, a variety of species condense in their atmospheres, forming clouds. Iron and silicate clouds shape the emergent spectra of L dwarfs, but these clouds dissipate at the L/T transition. A variety of other condensates are expected to form in cooler T dwarf atmospheres. These include Cr, MnS, Na{sub 2}S, ZnS, and KCl, but the opacity of these optically thinner clouds has not been included in previous atmosphere models. Here, we examine their effect on model T and Y dwarf atmospheres. The cloud structures and opacities are calculated using the Ackerman and Marley cloud model, which is coupled to an atmosphere model to produce atmospheric pressure-temperature profiles in radiative-convective equilibrium. We generate a suite of models between T{sub eff} = 400 and 1300 K, log g = 4.0 and 5.5, and condensate sedimentation efficiencies from f{sub sed} = 2 to 5. Model spectra are compared to two red T dwarfs, Ross 458C and UGPS 0722-05; models that include clouds are found to match observed spectra significantly better than cloudless models. The emergence of sulfide clouds in cool atmospheres, particularly Na{sub 2}S, may be a more natural explanation for the 'cloudy' spectra of these objects, rather than the reemergence of silicate clouds that wane at the L-to-T transition. We find that sulfide clouds provide a mechanism to match the near- and mid-infrared colors of observed T dwarfs. Our results indicate that including the opacity of condensates in T dwarf atmospheres is necessary to accurately determine the physical characteristics of many of the observed objects.

Morley, Caroline V.; Fortney, Jonathan J. [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); Marley, Mark S. [NASA Ames Research Center, Moffett Field, CA 94035 (United States); Visscher, Channon [Southwest Research Institute, Boulder, CO 80302 (United States); Saumon, Didier [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Leggett, S. K., E-mail: cmorley@ucolick.org [Gemini Observatory, Northern Operations Center, Hilo, HI 96720 (United States)

2012-09-10T23:59:59.000Z

459

Atmospheric propagation of THz radiation.  

SciTech Connect (OSTI)

In this investigation, we conduct a literature study of the best experimental and theoretical data available for thin and thick atmospheres on THz radiation propagation from 0.1 to 10 THz. We determined that for thick atmospheres no data exists beyond 450 GHz. For thin atmospheres data exists from 0.35 to 1.2 THz. We were successful in using FASE code with the HITRAN database to simulate the THz transmission spectrum for Mauna Kea from 0.1 to 2 THz. Lastly, we successfully measured the THz transmission spectra of laboratory atmospheres at relative humidities of 18 and 27%. In general, we found that an increase in the water content of the atmosphere led to a decrease in the THz transmission. We identified two potential windows in an Albuquerque atmosphere for THz propagation which were the regions from 1.2 to 1.4 THz and 1.4 to 1.6 THz.

Wanke, Michael Clement; Mangan, Michael A.; Foltynowicz, Robert J.

2005-11-01T23:59:59.000Z

460

Final Technical Report for "Collaborative Research: Regional climate-change projections through next-generation empirical and dynamical models"  

SciTech Connect (OSTI)

This project was a continuation of previous work under DOE CCPP funding in which we developed a twin approach of non-homogeneous hidden Markov models (NHMMs) and coupled ocean-atmosphere (O-A) intermediate-complexity models (ICMs) to identify the potentially predictable modes of climate variability, and to investigate their impacts on the regional-scale. We have developed a family of latent-variable NHMMs to simulate historical records of daily rainfall, and used them to downscale seasonal predictions. We have also developed empirical mode reduction (EMR) models for gaining insight into the underlying dynamics in observational data and general circulation model (GCM) simulations. Using coupled O-A ICMs, we have identified a new mechanism of interdecadal climate variability, involving the midlatitude oceans mesoscale eddy field and nonlinear, persistent atmospheric response to the oceanic anomalies. A related decadal mode is also identified, associated with the oceans thermohaline circulation. The goal of the continuation was to build on these ICM results and NHMM/EMR model developments and software to strengthen two key pillars of support for the development and application of climate models for climate change projections on time scales of decades to centuries, namely: (a) dynamical and theoretical understanding of decadal-to-interdecadal oscillations and their predictability; and (b) an interface from climate models to applications, in order to inform societal adaptation strategies to climate change at the regional scale, including model calibration, correction, downscaling and, most importantly, assessment and interpretation of spread and uncertainties in multi-model ensembles. Our main results from the grant consist of extensive further development of the hidden Markov models for rainfall simulation and downscaling specifically within the non-stationary climate change context together with the development of parallelized software; application of NHMMs to downscaling of rainfall projections over India; identification and analysis of decadal climate signals in data and models; and, studies of climate variability in terms of the dynamics of atmospheric flow regimes. Each of these project components is elaborated on below, followed by a list of publications resulting from the grant.

Robertson, A.W.; Ghil, M.; Kravtsov, K.; Smyth, P.J.

2011-04-08T23:59:59.000Z

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461

Final Technical Report for "Collaborative Research: Regional climate-change projections through next-generation empirical and dynamical models"  

SciTech Connect (OSTI)

This project was a continuation of previous work under DOE CCPP funding in which we developed a twin approach of non-homogeneous hidden Markov models (NHMMs) and coupled ocean-atmosphere (O-A) intermediate-complexity models (ICMs) to identify the potentially predictable modes of climate variability, and to investigate their impacts on the regional-scale. We have developed a family of latent-variable NHMMs to simulate historical records of daily rainfall, and used them to downscale seasonal predictions. We have also developed empirical mode reduction (EMR) models for gaining insight into the underlying dynamics in observational data and general circulation model (GCM) simulations. Using coupled O-A ICMs, we have identified a new mechanism of interdecadal climate variability, involving the midlatitude oceans?? mesoscale eddy field and nonlinear, persistent atmospheric response to the oceanic anomalies. A related decadal mode is also identified, associated with the oceans?? thermohaline circulation. The goal of the continuation was to build on these ICM results and NHMM/EMR model developments and software to strengthen two key pillars of support for the development and application of climate models for climate change projections on time scales of decades to centuries, namely: (a) dynamical and theoretical understanding of decadal-to-interdecadal oscillations and their predictability; and (b) an interface from climate models to applications, in order to inform societal adaptation strategies to climate change at the regional scale, including model calibration, correction, downscaling and, most importantly, assessment and interpretation of spread and uncertainties in multi-model ensembles. Our main results from the grant consist of extensive further development of the hidden Markov models for rainfall simulation and downscaling specifically within the non-stationary climate change context together with the development of parallelized software; application of NHMMs to downscaling of rainfall projections over India; identification and analysis of decadal climate signals in data and models; and, studies of climate variability in terms of the dynamics of atmospheric flow regimes. Each of these project components is elaborated on below, followed by a list of publications resulting from the grant.

Kravtsov, S.; Robertson, A. W.; Ghil, M.; Smyth, P. J.

2011-04-08T23:59:59.000Z

462

SoilVegetationAtmosphere Transfer Schemes and Large-Scale Hydrological Models (Proceedings of a symposium held during the Sixth IAHS Scientific Assembly at Maastricht, The Netherlands, July 2001).  

E-Print Network [OSTI]

JOSEPH P. McFADDEN & GLEN E. LISTON Department of Atmospheric Science, Colorado State University, Fort Research and Engineering Laboratory, Fort Wainwright, Alaska 99703, USA ROGER A. PIELKE, SR Department of Atmospheric Science, Colorado State University, Fort Collins, Colorado 80523, USA F. STUART CHAPIN, III

Pielke, Roger A.

463

Ionization in atmospheres of Brown Dwarfs and extrasolar planets IV. The Effect of Cosmic Rays  

E-Print Network [OSTI]

Cosmic rays provide an important source for free electrons in the Earth's atmosphere and also in dense interstellar regions where they produce a prevailing background ionization. We utilize a Monte Carlo cosmic ray transport model for particle energies of 1 MeV model for particle energies of 1 GeV model atmospheres of an example brown dwarf with effective temperature Teff = 1500 K, and two example giant gas planets (Teff = 1000 K, 1500 K). For the model brown dwarf atmosphere, the electron fraction is enhanced significantly by cosmic rays when the pressure pgas model atmosphere of the examp...

Rimmer, Paul

2013-01-01T23:59:59.000Z

464

Modelin the Transport and Chemical Evolution of Onshore and Offshore Emissions and Their Impact on Local and Regional Air Quality Using a Variable-Grid-Resolution Air Quality Model  

SciTech Connect (OSTI)

The overall objective of this research project was to develop an innovative modeling technique to adequately model the offshore/onshore transport of pollutants. The variable-grid modeling approach that was developed alleviates many of the shortcomings of the traditionally used nested regular-grid modeling approach, in particular related to biases near boundaries and the excessive computational requirements when using nested grids. The Gulf of Mexico region contiguous to the Houston-Galveston area and southern Louisiana was chosen as a test bed for the variable-grid modeling approach. In addition to the onshore high pollution emissions from various sources in those areas, emissions from on-shore and off-shore oil and gas exploration and production are additional sources of air pollution. We identified case studies for which to perform meteorological and air quality model simulations. Our approach included developing and evaluating the meteorological, emissions, and chemistry-transport modeling components for the variable-grid applications, with special focus on the geographic areas where the finest grid resolution was used. We evaluated the performance of two atmospheric boundary layer (ABL) schemes, and identified the best-performing scheme for simulating mesoscale circulations for different grid resolutions. Use of a newly developed surface data assimilation scheme resulted in improved meteorological model simulations. We also successfully ingested satellite-derived sea surface temperatures (SSTs) into the meteorological model simulations, leading to further improvements in simulated wind, temperature, and moisture fields. These improved meteorological fields were important for variable-grid simulations, especially related to capturing the land-sea breeze circulations that are critical for modeling offshore/onshore transport of pollutants in the Gulf region. We developed SMOKE-VGR, the variable-grid version of the SMOKE emissions processing model, and tested and evaluated this new system. We completed the development of our variable-grid-resolution air quality model (MAQSIP-VGR) and performed various diagnostic tests related to an enhanced cloud parameterization scheme. We also developed an important tool for variable-grid graphics using Google Earth. We ran the MAQSIP-VGR for the Houston-Galveston and southern Louisiana domains for an August 23 to September 2, 2002, episode. Results of the modeling simulations highlighted the usefulness of the variable-grid modeling approach when simulating complex terrain processes related to land and sea close to an urban area. Our results showed that realistic SST patterns based on remote sensing are critical to capturing the land-sea breeze, in particular the inland intrusion of the reversed mesoscale circulation that is critical for simulating air pollution over urban areas near coastal regions. Besides capturing the correct horizontal gradient between land and sea surface temperatures, it is important to use an adequate ABL scheme in order to quantify correctly the vertical profiles of various parameters. The ABL scheme should capture the dynamics of the marine boundary layer, which is not often considered in a typical simulation over land. Our results further showed the effect of using satellite-derived SSTs on the horizontal and vertical extent of the modeled pollution pattern, and the increase in hourly ozone concentrations associated with changes in ABL characteristics resulting from the enhanced mesoscale circulation in the lower troposphere.

Adel Hanna

2008-10-16T23:59:59.000Z

465

MODIS-Derived Boundary Conditions for a Mesoscale Climate Model: Application to Irrigated Agriculture in the Euphrates Basin  

E-Print Network [OSTI]

-level water consumption were more than doubled relative to simulations that did not incorporate MODIS data. 1. Introduction The dual pressures of local water consumption and global climate change threaten of potential evapotranspiration (PET) from the surface (Penman 1948). Surface conditions, including soil mois

Evans, Jason

466

Development of a Meso-Scale Material Model for Ballistic Fabric and Its Use in Flexible-Armor  

E-Print Network [OSTI]

.g., as reinforcements in rigid polymer matrix composites, PMCs, for lightweight vehicle- armor systems). Flexible-amide) fabric and an E-glass fiber/ethyl cellulose composite in body-armor systems can be linked to the Korean of the body- armor vests relative to up to 0.30 caliber threats, ceramic insert strike-plates are commonly

Grujicic, Mica

467

Experiences with the Application of the Non-Hydrostatic Mesoscale Model GESIMA for assessing Wind Potential in  

E-Print Network [OSTI]

.physik.uni-oldenburg.de/ehf *GKSS Research Center Geesthacht, Max-Planck-Stra?e 1, D-21494 Geesthacht, Germany To asses wind has been developed at the GKSS Research Center in Geesthacht, Germany ([8]). It numerically solves

Heinemann, Detlev