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Sample records for atmospheric mesoscale model

  1. Modeling the Atmospheric Boundary Layer Wind Response to Mesoscale Sea Surface Temperature

    E-Print Network [OSTI]

    Kurapov, Alexander

    Modeling the 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 region-Atmosphere Mesoscale Prediction System (COAMPS) atmospheric models. The SST-induced wind response is assessed from

  2. A new model to simulate the Martian mesoscale and microscale atmospheric circulation: Validation and first results

    E-Print Network [OSTI]

    Spiga, Aymeric

    A new model to simulate the Martian mesoscale and microscale atmospheric circulation: Validation) Mesoscale Model is a new versatile simulator of the Martian atmosphere and environment at horizontal scales, and photochemistry cycles. Since LMD-GCM large-scale simulations are also used to drive the mesoscale model

  3. Modeling the Atmospheric Boundary Layer Wind Response to Mesoscale Sea Surface Temperature Perturbations

    E-Print Network [OSTI]

    Kurapov, Alexander

    Modeling the Atmospheric Boundary Layer Wind Response to Mesoscale Sea Surface Temperature received 25 October 2013, in final form 24 July 2014) ABSTRACT The wind speed response to mesoscale SST Research and Forecasting (WRF) Model and the U.S. Navy Coupled Ocean­Atmosphere Mesoscale Prediction System

  4. 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]

    Daniels, Megan Hanako

    2010-01-01

    groundwater, land-surface, and mesoscale atmospheric model-and modification of mesoscale circulations. , Mon. Wea.J. Davis, The effects of mesoscale surface heterogeneity on

  5. 4, 54555514, 2004 Mesoscale modeling

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    ACPD 4, 5455­5514, 2004 Mesoscale modeling of combined aerosol and photo-oxidant processes M Union 2004 Atmospheric Chemistry and Physics Discussions Mesoscale modeling of combined aerosol­5514, 2004 Mesoscale modeling of combined aerosol and photo-oxidant processes M. Lazaridis et al. Title Page

  6. Intercomparison of oceanic and atmospheric forced and coupled mesoscale simulations

    E-Print Network [OSTI]

    Boyer, Edmond

    Intercomparison of oceanic and atmospheric forced and coupled mesoscale simulations Part I: Surface Abstract. A mesoscale non-hydrostatic atmospheric model has been coupled with a mesoscale oceanic model current. In order to analyze the eect of mesoscale coupling, three simulations are compared: the ®rst one

  7. Mesoscale coupled ocean-atmosphere interaction

    E-Print Network [OSTI]

    Seo, Hyodae

    2007-01-01

    mesoscale oceanic features are current coarse resolutionmesoscale r current variability associated with oceanic ringthe TIW- currents. These mesoscale oceanic and atmospheric

  8. Mesoscale Coupled Ocean-Atmosphere Interaction

    E-Print Network [OSTI]

    Seo, Hyodae

    2007-01-01

    mesoscale oceanic features are current coarse resolutionmesoscale r current variability associated with oceanic ringthe TIW- currents. These mesoscale oceanic and atmospheric

  9. Mesoscale Coupled Ocean-Atmosphere Interaction

    E-Print Network [OSTI]

    Seo, Hyodae

    2007-01-01

    2000: A Coupled Air-Sea Mesoscale Model: Experiments inWind Stress Curl from a Mesoscale Model. Mon. Wea. Rev. ,2006: Effect of Ocean Mesoscale Variability on the Mean

  10. Mesoscale coupled ocean-atmosphere interaction

    E-Print Network [OSTI]

    Seo, Hyodae

    2007-01-01

    2000: A Coupled Air-Sea Mesoscale Model: Experiments inWind Stress Curl from a Mesoscale Model. Mon. Wea. Rev. ,2006: Effect of Ocean Mesoscale Variability on the Mean

  11. Forecast of surface layer meteorological parameters at Cerro Paranal with a mesoscale atmospherical model

    E-Print Network [OSTI]

    Lascaux, Franck; Fini, Luca

    2015-01-01

    This article aims at proving the feasibility of the forecast of all the most relevant classical atmospherical parameters for astronomical applications (wind speed and direction, temperature) above the ESO ground-base site of Cerro Paranal with a mesoscale atmospherical model called Meso-Nh. In a precedent paper we have preliminarily treated the model performances obtained in reconstructing some key atmospherical parameters in the surface layer 0-30~m studying the bias and the RMSE on a statistical sample of 20 nights. Results were very encouraging and it appeared therefore mandatory to confirm such a good result on a much richer statistical sample. In this paper, the study was extended to a total sample of 129 nights between 2007 and 2011 distributed in different parts of the solar year. This large sample made our analysis more robust and definitive in terms of the model performances and permitted us to confirm the excellent performances of the model. Besides, we present an independent analysis of the model p...

  12. Mesoscale Modeling Spring Semester 2014

    E-Print Network [OSTI]

    van den Heever, Susan C.

    ATS730 Mesoscale Modeling Spring Semester 2014 Meeting Times: T/TH: 9-10:15am Room: ATS 101 is to present the development of the basic equations used in mesoscale models, as well as the various methods than on actual simulations of mesoscale phenomena or the evaluation of specific mesoscale models

  13. Mesoscale coupled ocean-atmosphere feedbacks in boundary current systems

    E-Print Network [OSTI]

    Putrasahan, Dian Ariyani

    2012-01-01

    Isolating Mesoscale Coupled Ocean-Atmosphere in the KuroshioSST coupler . . . . Chapter 3 Mesoscale Ocean-Atmosphere4.2 Impact of Mesoscale SST on Precipitation Chapter 4 vi

  14. ATMOSPHERIC DUST AND MESOSCALE/MICROSCALE METEOROLOGY. A. Spiga1 , S.R. Lewis1

    E-Print Network [OSTI]

    Spiga, Aymeric

    ATMOSPHERIC DUST AND MESOSCALE/MICROSCALE METEOROLOGY. A. Spiga1 , S.R. Lewis1 , and F. For- get2 to advances in computational resources and modeling techniques. Note also that mesoscale modeling and Large: general circulation models, mesoscale models, microscale models [Large-Eddy Simulations]. Figure 1

  15. Chromatin Ionic Atmosphere Analyzed by a Mesoscale Electrostatic Hin Hark Gan

    E-Print Network [OSTI]

    Schlick, Tamar

    Chromatin Ionic Atmosphere Analyzed by a Mesoscale Electrostatic Approach Hin Hark Gan and Tamar an electrostatic model to handle multivalent ions and compute the ionic distribution around a mesoscale chromatin

  16. AN URBAN SURFACE EXCHANGE PARAMETERISATION FOR MESOSCALE MODELS

    E-Print Network [OSTI]

    AN URBAN SURFACE EXCHANGE PARAMETERISATION FOR MESOSCALE MODELS ALBERTO MARTILLI1, , ALAIN CLAPPIER. A scheme to represent the impact of urban buildings on airflow in mesoscale atmospheric models is presented the presence of the buildings. The parameterisation is introduced into a mesoscale model and tested

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

    SciTech Connect (OSTI)

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

    2013-10-01

    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.

  18. THE SIMULATION OF FINE SCALE NOCTURNAL BOUNDARY LAYER MOTIONS WITH A MESO-SCALE ATMOSPHERIC MODEL

    SciTech Connect (OSTI)

    Werth, D.; Kurzeja, R.; Parker, M.

    2009-04-02

    A field project over the Atmospheric Radiation Measurement-Clouds and Radiation Testbed (ARM-CART) site during a period of several nights in September, 2007 was conducted to explore the evolution of the low-level jet (LLJ). Data was collected from a tower and a sodar and analyzed for turbulent behavior. To study the full range of nocturnal boundary layer (NBL) behavior, the Regional Atmospheric Modeling System (RAMS) was used to simulate the ARM-CART NBL field experiment and validated against the data collected from the site. This model was run at high resolution, and is ideal for calculating the interactions among the various motions within the boundary layer and their influence on the surface. The model reproduces adequately the synoptic situation and the formation and dissolution cycles of the low-level jet, although it suffers from insufficient cloud production and excessive nocturnal cooling. The authors suggest that observed heat flux data may further improve the realism of the simulations both in the cloud formation and in the jet characteristics. In a higher resolution simulation, the NBL experiences motion on a range of timescales as revealed by a wavelet analysis, and these are affected by the presence of the LLJ. The model can therefore be used to provide information on activity throughout the depth of the NBL.

  19. LMD Martian Mesoscale Model User Manual

    E-Print Network [OSTI]

    Spiga, Aymeric

    LMD Martian Mesoscale Model [LMD-MMM] User Manual A. Spiga aymeric.spiga@upmc.fr Laboratoire de;#12;Contents 1 What is the LMD Martian Mesoscale Model? 3 1.1 Dynamical core on mesoscale levels . . . . . . . . . . . . . . . 35 iii #12;iv User Manual for the LMD Martian Mesoscale Model

  20. Modeling of passive microwave responses in convective situations using output from mesoscale models

    E-Print Network [OSTI]

    Pardo-Carrión, Juan R.

    Modeling of passive microwave responses in convective situations using output from mesoscale models using output from nonhydrostatic mesoscale atmospheric model, Meso-NH, simulations. The radiative for a systematic evaluation of the mesoscale cloud models. An overall good agreement is obtained for both

  1. Sleep Dynamics and Seizure Control in a Mesoscale Cortical Model

    E-Print Network [OSTI]

    Lopour, Beth Ann

    2009-01-01

    Contributions . . . . . . . . . 2 Mesoscale Cortical Modelstates in h e from the mesoscale cortical model, here- afterand Seizure Control in a Mesoscale Cortical Model by Beth

  2. Mesoscale Model Development and the Meteorological Community

    E-Print Network [OSTI]

    Mass, Clifford F.

    Mesoscale Model Development and the Meteorological Community Cliff Mass University of Washington: Although the U.S. remains a leader in mesoscale model development and application, the community is not fulfilling its potential. The resources of the U.S. mesoscale forecasting community are considerable

  3. MESOSCALE AVERAGING OF NUCLEATION AND GROWTH MODELS

    E-Print Network [OSTI]

    Ferguson, Thomas S.

    MESOSCALE AVERAGING OF NUCLEATION AND GROWTH MODELS MARTIN BURGER , VINCENZO CAPASSO , AND LIVIO-Kolmogorov relations for the degree of crystallinity. By relating the computation of expected values to mesoscale averaging, we obtain a suitable description of the process at the mesoscale. We show how the variance

  4. Modelling and numerical approximation of a 2.5D set of equations for mesoscale atmospheric processes

    E-Print Network [OSTI]

    Kalise, Dante

    2011-01-01

    The set of 3D inviscid primitive equations for the atmosphere is dimensionally reduced by a Discontinuous Galerkin discretization in one horizontal direction. The resulting model is a 2D system of balance laws where with a source term depending on the layering procedure and the choice of coupling fluxes, which is established in terms of upwind considerations. The "2.5D" system is discretized via a WENO-TVD scheme based in a flux limiter centered approach. We study four tests cases related to atmospheric phenomena to analyze the physical validity of the model.

  5. Mesoscale Modeling Framework Design: Subcontract Report | SciTech...

    Office of Scientific and Technical Information (OSTI)

    Mesoscale Modeling Framework Design: Subcontract Report Citation Details In-Document Search Title: Mesoscale Modeling Framework Design: Subcontract Report You are accessing a...

  6. STATISTICAL MECHANICS MODELING OF MESOSCALE DEFORMATION IN METALS...

    Office of Scientific and Technical Information (OSTI)

    STATISTICAL MECHANICS MODELING OF MESOSCALE DEFORMATION IN METALS Anter El-Azab 36 MATERIALS SCIENCE dislocation dynamics; mesoscale deformation of metals; crystal mechanics...

  7. Analytical mesoscale modeling of aeolian sand transport

    E-Print Network [OSTI]

    Marc Lämmel; Anne Meiwald; Klaus Kroy

    2014-05-03

    We analyze the mesoscale structure of aeolian sand transport, based on a recently developed two-species continuum model. The calculated sand flux and important average characteristics of the grain trajectories are found to be in remarkable agreement with field and wind-tunnel data. We conclude that the essential mesoscale physics is insensitive to unresolved details on smaller scales and well captured by the coarse-grained analytical model, thus providing a sound basis for precise and numerically efficient mesoscale modeling of aeolian structure formation.

  8. Ocean color and atmospheric dimethyl sulfide: On their mesoscale variability

    E-Print Network [OSTI]

    Matrai, Patricia A; Balch, William M; Cooper, David J; Saltzman, Eric S

    1993-01-01

    periods of' time, covering mesoscale Campbell, J. W. and W.Dimethyl Sulfide' On Their Mesoscale Variability PATRICIA A.Miami, Miami, Florida The mesoscale variability of dimethyl

  9. Mesoscale circulations and atmospheric CO2 variations in the Tapajos Region, Para, Brazil

    E-Print Network [OSTI]

    Collett Jr., Jeffrey L.

    Mesoscale circulations and atmospheric CO2 variations in the Tapajo´s Region, Para´, Brazil Lixin; published 2 November 2005. [1] We have investigated mesoscale circulations and atmospheric CO2 variations over a heterogeneous landscape of forests, pastures, and large rivers during the Santare´m Mesoscale

  10. Satellite observations of mesoscale ocean features and copropagating atmospheric surface fields in the tropical belt

    E-Print Network [OSTI]

    Xie, Shang-Ping

    Satellite observations of mesoscale ocean features and copropagating atmospheric surface fields speed and sea surface temperature (SST) over mesoscale ocean features in certain frontal regions. The aim of this study is to determine to what extent mesoscale ocean dynamics modifies the surface wind

  11. Heat transport and weakening of atmospheric stability induced by mesoscale flows

    E-Print Network [OSTI]

    Pielke, Roger A.

    Heat transport and weakening of atmospheric stability induced by mesoscale flows G. A. Dalu boundary layer (CBL) is transported upward into the midtroposphere by mesoscale flows, and how the air, and diffusion, associated with the mesoscale flow, is more clearly shown when the forcing is periodic in time

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

    E-Print Network [OSTI]

    WIND ATLAS FOR EGYPT: MEASUREMENTS, MICRO- AND MESOSCALE MODELLING Niels G. Mortensen1 , Jens atlas based on long-term reanalysis data and a mesoscale model (KAMM). The mean absolute error comparing atlas based on long-term reanalysis data and a mesoscale model, KAMM. The observations have been

  13. Effects of urban land cover modifications in a mesoscale meteorological model on surface temperature and heat fluxes in the Phoenix metropolitan area.

    E-Print Network [OSTI]

    Hall, Sharon J.

    Effects of urban land cover modifications in a mesoscale meteorological model on surface between the two simulations. Mesoscale atmospheric models such as the Pennsylvania State University for the Phoenix metropolitan area was implemented in the fifth- generation PSU/NCAR mesoscale meteorological model

  14. A Mesoscale Diffusion Model in Population Genetics with

    E-Print Network [OSTI]

    O'Leary, Michael

    ' & $ % A Mesoscale Diffusion Model in Population Genetics with Dynamic Fitness Mike O'Leary Towson University Judith R. Miller Georgetown University 1 #12;A mesoscale diffusion model in population genetics that dominance and epistasis are absent. April 28, 2005 Mike O'Leary and Judith Miller Slide 2 #12;A mesoscale

  15. Identification of a mesoscale model with multiscale experimental observations

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Identification of a mesoscale model with multiscale experimental observations M.T. Nguyen, C and at mesoscale within the framework of a heterogeneous microstruc- ture which is modeled by a random elastic measurements of the displacement fields at macroscale and at mesoscale performed with only a single specimen

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

    E-Print Network [OSTI]

    Raman, Sethu

    in Air Pollution, Vol 9, p. 424. Chapter 9 Numerical modeling of gas deposition and bi- directional surface­atmosphere exchanges in mesoscale air pollution systems Devdutta S. Niyogi & Sethu Raman North to develop deposition flux estimates in air pollution models. An interesting scenario also develops when

  17. STATISTICAL MECHANICS MODELING OF MESOSCALE DEFORMATION IN METALS...

    Office of Scientific and Technical Information (OSTI)

    and computational modeling of dislocation dynamics of mesoscale deformation of metal single crystals. Specifically, the work aimed to implement a continuum statistical...

  18. Mesoscale Modeling of Fuel Swelling and Restructuring: Coupling...

    Office of Scientific and Technical Information (OSTI)

    Conference: Mesoscale Modeling of Fuel Swelling and Restructuring: Coupling Microstructure evolution and Mechanical Localization. Citation Details In-Document Search Title:...

  19. A study of mesoscale gravity waves over the North Atlantic with satellite observations and a mesoscale model

    E-Print Network [OSTI]

    A study of mesoscale gravity waves over the North Atlantic with satellite observations and a mesoscale model Dong L. Wu Jet Propulsion Laboratory, California Institute of Technology, Pasadena and compare AMSU-A observations to simulations from a mesoscale model (MM5). The simulated gravity waves

  20. Nighttime atmospheric stability changes and their effects on the temporal intensity of a mesoscale convective complex 

    E-Print Network [OSTI]

    Hovis, Jeffrey Scott

    1988-01-01

    NIGHTTIME ATMOSPHERIC STABILITY CHANGES AND THEIR EFFECTS ON THE TEMPORAL INTENSITY OF A MESOSCALE CONVECTIVE COMPLEX A Thesis JEFFREY SCOTT HOVIS Submitted to the Graduate College of Texas A&M University in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE May 1988 Major Subject: Meteorology NIGHTTIME ATMOSPHERIC STABILITY CHANGES AND THEIR EFFECTS ON THE TEMPORAL INTENSITY OF A MESOSCALE CONVECTIVE COMPLEX A Thesis JEFFREY SCOTT HOVIS Approved as to style...

  1. Mesoscale modelling of polyelectrolyte electrophoresis

    E-Print Network [OSTI]

    Kai Grass; Christian Holm

    2009-02-11

    The electrophoretic behaviour of flexible polyelectrolyte chains ranging from single monomers up to long fragments of hundred repeat units is studied by a mesoscopic simulation approach. Abstracting from the atomistic details of the polyelectrolyte and the fluid, a coarse-grained molecular dynamics model connected to a mesoscopic fluid described by the Lattice Boltzmann approach is used to investigate free-solution electrophoresis. Our study demonstrates the importance of hydrodynamic interactions for the electrophoretic motion of polyelectrolytes and quantifies the influence of surrounding ions. The length-dependence of the electrophoretic mobility can be understood by evaluating the scaling behavior of the effective charge and the effective friction. The perfect agreement of our results with experimental measurements shows that all chemical details and fluid structure can be safely neglected, and a suitable coarse-grained approach can yield an accurate description of the physics of the problem, provided that electrostatic and hydrodynamic interactions between all entities in the system, i.e., the polyelectrolyte, dissociated counterions, additional salt and the solvent, are properly accounted for. Our model is able to bridge the single molecule regime of a few nm up to macromolecules with contour lengths of more than 100 nm, a length scale that is currently not accessible to atomistic simulations.

  2. Impact of Agricultural Practice on Regional Climate in a Coupled Land Surface Mesoscale Model

    E-Print Network [OSTI]

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

    2004-01-01

    winter wheat belt on the mesoscale environment, Monthlygeneration Penn State/NCAR mesoscale model (MM5), NCAR,in a Coupled Land Surface Mesoscale Model H.S. Cooley Energy

  3. Constructing Irregular Surfaces to Enclose Macromolecular Complexes for Mesoscale Modeling Using the Discrete

    E-Print Network [OSTI]

    Schlick, Tamar

    Constructing Irregular Surfaces to Enclose Macromolecular Complexes for Mesoscale Modeling Using proteins. DiSCO is generally applicable to other interesting macromolecular systems for which mesoscale

  4. Microscale and mesoscale discrete models for dynamic fracture of structures built of brittle material

    E-Print Network [OSTI]

    Microscale and mesoscale discrete models for dynamic fracture of structures built of brittle are derived either at microscale with random distribution of material properties or at a mesoscale

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

    SciTech Connect (OSTI)

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

    2014-06-01

    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.

  6. Mesoscale Spectra of Mars's Atmosphere Derived from MGS TES Infrared Radiances TAKESHI IMAMURA

    E-Print Network [OSTI]

    and potential energy spectra as a function of horizontal wavenumber. Each spectrum has two different wave spectra of the atmospheric potential energy of Mars at mesoscales (wavelengths of 64­957 km) were obtained-scale ends, the spectra sometimes show prominent steepening with slopes from 2 to 3. The power peaks

  7. Mesoscale Variations of the Atmospheric Snow Line over the Northern Sierra Nevada: Multiyear Statistics, Case Study, and Mechanisms

    E-Print Network [OSTI]

    Minder, Justin

    Mesoscale Variations of the Atmospheric Snow Line over the Northern Sierra Nevada: Multiyear to rainfall, the snow line, can intersect the terrain at an elevation hundreds of meters below its elevation in the free air upwind. This mesoscale lowering of the snow line affects both the accumulation of mountain

  8. Modeling of Alpine Atmospheric Dynamics II

    E-Print Network [OSTI]

    Gohm, Alexander

    Modeling of Alpine Atmospheric Dynamics II 707.424, VU 2, SS2005 Unit 7: Model code structure: mesoscale convective system 17-18 April 2004: Sierra hydraulic jump case 21 January 2005: the "Universiade) Introduction (brief description of the phenomenon and a description of the model and of the measurements

  9. Intercomparison of mesoscale meteorological models for precipitation forecasting Hydrology and Earth System Sciences, 7(6), 799811 (2003) EGU

    E-Print Network [OSTI]

    Boyer, Edmond

    2003-01-01

    Intercomparison of mesoscale meteorological models for precipitation forecasting 799 Hydrology and Earth System Sciences, 7(6), 799811 (2003) © EGU Intercomparison of mesoscale meteorological models

  10. Author's personal copy Mesoscale modeling of electric double layer capacitors with three-dimensional

    E-Print Network [OSTI]

    Pilon, Laurent

    Author's personal copy Mesoscale modeling of electric double layer capacitors with three Mesoscale modeling Mesoporous electrodes a b s t r a c t This paper presents general mathematical

  11. THE APPLICATION OF AN EVOLUTIONARY ALGORITHM TO THE OPTIMIZATION OF A MESOSCALE METEOROLOGICAL MODEL

    SciTech Connect (OSTI)

    Werth, D.; O'Steen, L.

    2008-02-11

    We show that a simple evolutionary algorithm can optimize a set of mesoscale atmospheric model parameters with respect to agreement between the mesoscale simulation and a limited set of synthetic observations. This is illustrated using the Regional Atmospheric Modeling System (RAMS). A set of 23 RAMS parameters is optimized by minimizing a cost function based on the root mean square (rms) error between the RAMS simulation and synthetic data (observations derived from a separate RAMS simulation). We find that the optimization can be efficient with relatively modest computer resources, thus operational implementation is possible. The optimization efficiency, however, is found to depend strongly on the procedure used to perturb the 'child' parameters relative to their 'parents' within the evolutionary algorithm. In addition, the meteorological variables included in the rms error and their weighting are found to be an important factor with respect to finding the global optimum.

  12. Segmentation and Tracking of Mesoscale Eddies in Numeric Ocean Models Vishal Sood, Bin John, Ramprasad Balasubramanian and Amit Tandon*

    E-Print Network [OSTI]

    Tandon, Amit

    Segmentation and Tracking of Mesoscale Eddies in Numeric Ocean Models Vishal Sood, Bin John suggested that the mesoscale eddies and mesoscale features play a strong role in carrying heat poleward oceanographers an invaluable tool to assess mesoscale eddies and the Lagrangian characteristics of this mesoscale

  13. Modeled biogeochemical responses to mesoscale eddies in the South China Sea

    E-Print Network [OSTI]

    Xiu, Peng

    Modeled biogeochemical responses to mesoscale eddies in the South China Sea Peng Xiu1 and Fei Chai1] Mesoscale eddies are observed each year in the South China Sea (SCS); however, their contributions physicalbiogeochemical model to evaluate the eddy impact. We first track the modeled mesoscale eddies in the SCS

  14. Development of the Flux-Adjusting Surface Data Assimilation System for Mesoscale Models

    E-Print Network [OSTI]

    Niyogi, Dev

    Development of the Flux-Adjusting Surface Data Assimilation System for Mesoscale Models KIRAN and temperature and for surface air temperature and water vapor mixing ratio for mesoscale models. In the FASDAS-field variables. The FASDAS is coupled to a land surface submodel in a three-dimensional mesoscale model and tests

  15. 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]

    Schlegel, Nicole-Jeanne

    2011-01-01

    ice sheet model with a mesoscale climate model By Nicole-ice sheet model with a mesoscale climate model Copyrightice sheet model with a mesoscale climate model by Nicole-

  16. Mass and charge flow in nanopores: numerical simulation via mesoscale models

    E-Print Network [OSTI]

    Cecconi, Fabio

    Mass and charge flow in nanopores: numerical simulation via mesoscale models Mauro Chinappi1 at nanoscale is here addressed via a recent developed mesoscale approach. In particular the flow

  17. Mesoscale Modeling of a Li-Ion Polymer Cell Chia-Wei Wanga,

    E-Print Network [OSTI]

    Sastry, Ann Marie

    Mesoscale Modeling of a Li-Ion Polymer Cell Chia-Wei Wanga, * and Ann Marie Sastrya,b,c, *,z, the study reported critical data required for mesoscale numerical simulation, including ionic con- ductivity

  18. Mesoscale modeling of electrical percolation in fiber-filled systems Sameer S. Rahatekar and Marc Hamm

    E-Print Network [OSTI]

    Elliott, James

    Mesoscale modeling of electrical percolation in fiber-filled systems Sameer S. Rahatekar and Marc online 4 October 2005 The research described in this paper primarily involves mesoscale simulations

  19. Wind resource assessment with a mesoscale non-hydrostatic model

    E-Print Network [OSTI]

    Boyer, Edmond

    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

  20. A Diagnostic Suite of Models for the Evaluation of Oceanic Mesoscale Eddy Parameterizations

    E-Print Network [OSTI]

    Fox-Kemper, Baylor

    A Diagnostic Suite of Models for the Evaluation of Oceanic Mesoscale Eddy Parameterizations by S. D of Oceanic Mesoscale Eddy Parameterizations written by S. D. Bachman has been approved for the Department and Oceanic Sciences) A Diagnostic Suite of Models for the Evaluation of Oceanic Mesoscale Eddy

  1. Atomistic and Mesoscale Modeling of Dislocation B.S., Huazhong University of Science and Technology (1995)

    E-Print Network [OSTI]

    Cai, Wei

    1995-01-01

    Atomistic and Mesoscale Modeling of Dislocation Mobility by Wei Cai B.S., Huazhong University by . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Sow-Hsin Chen Chairman, Department Committee on Graduate Students #12;2 #12;Atomistic and Mesoscale theories and simulations of dislocations in Si and BCC transition metals, with emphasis on the atomistic-mesoscale

  2. DETECTING AND TRACKING OF MESOSCALE OCEANIC FEATURES IN THE MIAMI ISOPYCNIC CIRCULATION OCEAN MODEL

    E-Print Network [OSTI]

    Tandon, Amit

    DETECTING AND TRACKING OF MESOSCALE OCEANIC FEATURES IN THE MIAMI ISOPYCNIC CIRCULATION OCEAN MODEL developed to automatically detect, locate and track mesoscale eddies spatially and temporally. Using an invaluable tool to assess mesoscale oceanic features. Key Words ­ Scientific Visualization, Eddy Detection

  3. Mesoscale Modeling of LX-17 Under Isentropic Compression

    SciTech Connect (OSTI)

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

    2010-03-06

    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.

  4. Mesoscale modeling of metal-loaded high explosives

    SciTech Connect (OSTI)

    Bdzil, John Bohdan [Los Alamos National Laboratory; Lieberthal, Brandon [UNIV OF ILLINOIS; Srewart, Donald S [UNIV OF ILLINOIS

    2010-01-01

    We describe a 3D approach to modeling multi-phase blast explosive, which is primarily condensed explosive by volume with inert embedded particles. These embedded particles are uniform in size and placed on the array of a regular lattice. The asymptotic theory of detonation shock dynamics governs the detonation shock propagation in the explosive. Mesoscale hydrodynamic simulations are used to show how the particles are compressed, deformed, and accelerated by the high-speed detonation products flow.

  5. The Retrieval of Ice Water Content from Radar Reflectivity Factor and Temperature and Its Use in Evaluating a Mesoscale Model

    E-Print Network [OSTI]

    Hogan, Robin

    in Evaluating a Mesoscale Model ROBIN J. HOGAN, MARION P. MITTERMAIER,* AND ANTHONY J. ILLINGWORTH Department-GHz radar with the values held in the Met Office mesoscale forecast model, for eight precipitating

  6. Mesoscale modeling of colloidal suspensions with adsorbing solutes

    E-Print Network [OSTI]

    Rei Tatsumi; Osamu Koike; Yukio Yamaguchi

    2015-01-14

    We construct a mesoscale model of colloidal suspensions that contain solutes reversibly adsorbing onto the colloidal particle surfaces. The present model describes the coupled dynamics of the colloidal particles, the host fluid, and the solutes through the Newton-Euler equations of motion, the hydrodynamic equations, and the advection-diffusion equation, respectively. The solute adsorption is modeled through a square-well potential, which represents a short-range attractive interaction between a particle and a solute molecule. The present model is formulated to be solved through direct numerical simulations. Some numerical results are presented to validate the simulations. The present model enables investigations of solute adsorption effects in the presence of a fluid flow and an inhomogeneous solute concentration distribution.

  7. Coupled Mesoscale-Large-Eddy Modeling of Realistic Stable Boundary Layer Turbulence

    E-Print Network [OSTI]

    Wang, Yao; Manuel, Lance

    2013-01-01

    Site-specific flow and turbulence information are needed for various practical applications, ranging from aerodynamic/aeroelastic modeling for wind turbine design to optical diffraction calculations. Even though highly desirable, collecting on-site meteorological measurements can be an expensive, time-consuming, and sometimes a challenging task. In this work, we propose a coupled mesoscale-large-eddy modeling framework to synthetically generate site-specific flow and turbulence data. The workhorses behind our framework are a state-of-the-art, open-source atmospheric model called the Weather Research and Forecasting (WRF) model and a tuning-free large-eddy simulation (LES) model. Using this coupled framework, we simulate a nighttime stable boundary layer (SBL) case from the well-known CASES-99 field campaign. One of the unique aspects of this work is the usage of a diverse range of observations for characterization and validation. The coupled models reproduce certain characteristics of observed low-level jets....

  8. New Efficient Sparse SpaceTime Algorithms for Superparameterization on Mesoscales

    E-Print Network [OSTI]

    Xing, Yulong

    New Efficient Sparse Space­Time Algorithms for Superparameterization on Mesoscales YULONG XING-scale and mesoscale processes provided by a cloud-resolving model (CRM) embedded in each column of a large-scale model for limited-area mesoscale ensemble forecasting. 1. Introduction Atmospheric processes of weather and climate

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

    E-Print Network [OSTI]

    Niyogi, Dev

    (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 model (GEM) as a land surface scheme for mesoscale weather forecasting model applications. The GEM

  10. Modeling mesoscale eddies V.M. Canuto a,b,*, M.S. Dubovikov a,c

    E-Print Network [OSTI]

    Modeling mesoscale eddies V.M. Canuto a,b,*, M.S. Dubovikov a,c a Goddard Institute for Spaces November 2003 Available online 6 December 2003 Abstract Mesoscale eddies are not resolved in coarse, no generally accepted model exists for the former; in the latter case, mesoscales are modeled with a bolus

  11. An implicit finite-element model for 3D non-hydrostatic mesoscale ocean M.A. Maidana1

    E-Print Network [OSTI]

    Politècnica de Catalunya, Universitat

    An implicit finite-element model for 3D non-hydrostatic mesoscale ocean flows M.A. Maidana1 , J-dimensional, non-hydrostatic mesoscale ocean flows. The model considered here incorporates surface wind stress and the idea of using unstructured grids for modelling mesoscale ocean dynamics sounds very attractive given

  12. Strain in the mesoscale kinetic Monte Carlo model for sintering

    E-Print Network [OSTI]

    Bjørk, R; Tikare, V; Olevsky, E; Pryds, N

    2014-01-01

    Shrinkage strains measured from microstructural simulations using the mesoscale kinetic Monte Carlo (kMC) model for solid state sintering are discussed. This model represents the microstructure using digitized discrete sites that are either grain or pore sites. The algorithm used to simulate densification by vacancy annihilation removes an isolated pore site at a grain boundary and collapses a column of sites extending from the vacancy to the surface of sintering compact, through the center of mass of the nearest grain. Using this algorithm, the existing published kMC models are shown to produce anisotropic strains for homogeneous powder compacts with aspect ratios different from unity. It is shown that the line direction biases shrinkage strains in proportion the compact dimension aspect ratios. A new algorithm that corrects this bias in strains is proposed; the direction for collapsing the column is determined by choosing a random sample face and subsequently a random point on that face as the end point for...

  13. The effect of shear on heat budgets in a simulated Mesoscale Convective System 

    E-Print Network [OSTI]

    Shaw, Justin David

    2000-01-01

    The evolution and structure of simulated Mesoscale Convective Systems (MCS) were examined using the Collaborative Model for Multiscale Atmospheric Simulations. Three numerical simulations were performed, with the amount ...

  14. The impact of agricultural intensification and irrigation on landatmosphere interactions and Indian monsoon precipitation --A mesoscale modeling perspective

    E-Print Network [OSTI]

    Douglas, Ellen M.

    and Indian monsoon precipitation -- A mesoscale modeling perspective E.M. Douglas a, , A. Beltrán-Przekurat b and regional convergence, mesoscale convection, and precipitation patterns over the Indian monsoon region. Four circulation pattern and changes in mesoscale precipitation. These agricultural changes, including irrigation

  15. Multiscale models for synoptic-mesoscale interactions in the ocean1 , K. Shafer Smith, Andrew J. Majda2

    E-Print Network [OSTI]

    Majda, Andrew J.

    Multiscale models for synoptic-mesoscale interactions in the ocean1 Ian Grooms , K. Shafer Smith of the midlatitude oceanic synoptic scale -- where coherent features such as jets and rings form -- and the mesoscale, defined by the internal deformation scale. The synoptic scale and mesoscale overlap at low and mid

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

    E-Print Network [OSTI]

    Smith, K. Shafer

    Mesoscale Eddy Energy Locality in an Idealized Ocean Model IAN GROOMS, LOUIS-PHILIPPE NADEAU, AND K investigates the energy budget of mesoscale eddies in wind-driven two-layer quasigeostrophic simulations of eddy energy are ``nonlocal.'' Many mesoscale parameterizations assume that statistics of the unresolved

  17. Isolating the role of mesoscale eddies in mixing of a passive tracer in an eddy resolving model

    E-Print Network [OSTI]

    Miami, University of

    Isolating the role of mesoscale eddies in mixing of a passive tracer in an eddy resolving model February 2008; published 16 May 2008. [1] This study examines the role of mesoscale eddies in distribution was replaced by a down-gradient diffusive parameterization. Our results demonstrate that advection by mesoscale

  18. The impact of agricultural intensification and irrigation on landatmosphere interactions and Indian monsoon precipitation --A mesoscale modeling perspective

    E-Print Network [OSTI]

    Niyogi, Dev

    and Indian monsoon precipitation -- A mesoscale modeling perspective E.M. Douglas a, , A. Beltrán-Przekurat b convergence, mesoscale convection, and precipitation patterns over the Indian monsoon region. Four experiments pattern and changes in mesoscale precipitation. These agricultural changes, including irrigation modify

  19. Numerical modeling of roll structures in mesoscale vortexes over the Black Sea

    E-Print Network [OSTI]

    Iarova, D A

    2014-01-01

    This paper is a case study of horizontal atmospheric rolls that formed over the Black Sea on 16 August 2007. The rolls were discovered in WRF modeling results for a mesoscale cyclone that originated over the sea on 15 August 2007. The roll formation mechanisms, such as Rayleigh-Benard convective instability, dynamic instability, advection and stretching of vertical velocity field inhomogeneities, are considered. It is shown that indeed convective instability played an important role in the roll formation but dynamic instability did not occur. In order to distinguish other possible mechanisms of the roll formation numerical experiments were performed. In these experiments sea surface temperature in the initial conditions was decreased in order to prevent convective instability. Even though convective instability was suppressed roll-like structures still appeared in the modeling results, although their height and circulation velocity were smaller than in the control run. It was found that these structures were ...

  20. Modeling of passive microwave responses in convective situations using output from mesoscale models

    E-Print Network [OSTI]

    Chaboureau, Jean-Pierre

    Modeling of passive microwave responses in convective situations using output from mesoscale models 2003; revised 27 January 2004; accepted 5 February 2004; published 30 March 2004. [1] Passive microwave, which essentially sense cloud tops. Therefore passive microwave observations are a very promising tool

  1. Mesoscale environmental models accompanying convection in the Texas HIPLEX region / by Mark Edward Humbert 

    E-Print Network [OSTI]

    Humbert, Mark Edward

    1980-01-01

    MESOSCALE ENVIRONMENTAL MODELS ACCOMPANYING CONVECTION IN THE TEXAS HIPLEX REGION A Thesis by MARK EDWARD HUMBERT Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER... OF SCIENCE May 1980 Major Subject: Meteorology MESOSCALE ENVIRONMENTAL MODELS ACCOMPANYING CONVECTION IN THE TEXAS HIPLEX REGION A Thesis by MARK EDWARD HUMBERT Approved as to style and content by: (Chairman of Co ttee) (Head of Department) (Member...

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

    E-Print Network [OSTI]

    Walters, Michael Kent

    1985-01-01

    DEVELOPMENT AND VALIDATION OF A VERTICALLY TWO-DIMENSIONAL MESOSCALE NUMERICAL MODEL A Thesis by MICHAEL KENT WALTERS Submitted to the Graduate College of Texas AsM University in partial fulfillment of the requirement for the degree of MASTER... OF SCIENCE August 1985 Major Subject: Meteorology DEVELOPMENT AND VALIDATION OF A VERTICALLY TWO-DIMENSIONAL MESOSCALE NUMERICAL MODEL A Thesis by MICHAEL KENT WALTERS Approved as to style and content by: Dusan Djuric (Chair of Committee) WP...

  3. Moist processes and the quasi-hydrostatic approximation in a mesoscale numerical model 

    E-Print Network [OSTI]

    Kennedy, Charles Joseph

    1987-01-01

    MOIST PROCESSES AND THE QUASI-HYDROSTATIC APPROXIMATION IN A MESOSCALE NUMERICAL MODEL A Thesis by CHARLES JOSEPH KENNEDY Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree... of MASTER OF SCIENCE December 1987 Major Subject: Meteorology MOIST PROCESSES AND THE QUASI-HYDROSTATIC APPROXIMATION IN A MESOSCALE NUMERICAL MODEL A Thesis by CHARLES JOSEPH KENNEDY Approved as to style and content by: Dusan Djuric (Chair...

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

    E-Print Network [OSTI]

    winds. The two model types presented above are used in urban climatology in order to comprehend townA PHYSICALLY-BASED SCHEME FOR THE URBAN ENERGY BUDGET IN ATMOSPHERIC MODELS VALÉRY MASSON Centre) Abstract. An urban surface scheme for atmospheric mesoscale models is presented. A generaliz- ation

  5. Ensemble Atmospheric Dispersion Modeling

    SciTech Connect (OSTI)

    Addis, R.P.

    2002-06-24

    Prognostic atmospheric dispersion models are used to generate consequence assessments, which assist decision-makers in the event of a release from a nuclear facility. Differences in the forecast wind fields generated by various meteorological agencies, differences in the transport and diffusion models, as well as differences in the way these models treat the release source term, result in differences in the resulting plumes. Even dispersion models using the same wind fields may produce substantially different plumes. This talk will address how ensemble techniques may be used to enable atmospheric modelers to provide decision-makers with a more realistic understanding of how both the atmosphere and the models behave.

  6. Synoptic and mesoscale controls on the isotopic composition of individual storms systems striking the western US

    E-Print Network [OSTI]

    Johnson, KR; Berkelhammer, M; Stott, L; Kei, Y

    2012-01-01

    011-1262-3 Synoptic and mesoscale controls on the isotopicet al. : Synoptic and mesoscale controls on the isotopicrecord of syn- optic and mesoscale atmospheric processes. In

  7. The Impacts of Indirect Soil Moisture Assimilation and Direct Surface Temperature and Humidity Assimilation on a Mesoscale Model Simulation of an Indian

    E-Print Network [OSTI]

    Niyogi, Dev

    Assimilation on a Mesoscale Model Simulation of an Indian Monsoon Depression VINODKUMAR AND A. CHANDRASEKAR-generation Pennsylvania State University­NCAR Mesoscale Model (MM5) simulation utilized the humidity and temperature

  8. Bull. Disas. Prey. Res. Inst., Kyoto Univ., Vol. 45, Part 2,3 No. 391, February, 1996 61 A Simple Water Balance Model for a Mesoscale Catchment

    E-Print Network [OSTI]

    Takada, Shoji

    A Simple Water Balance Model for a Mesoscale Catchment Based on Heterogeneous Soil Water Storage Capacity, for the mesoscale catchments of Japan and Thailand. Sensitivity analysis of the model parameters has been conducted

  9. 4, 497545, 2011 atmosphere-wildland

    E-Print Network [OSTI]

    Mandel, Jan

    by the coupling of a mesoscale weather 498 #12;GMDD 4, 497­545, 2011 Coupled atmosphere-wildland model WRF-Fire 3

  10. Dynamical model of mesoscales in z-coordinates V.M. Canuto a,b,*, M.S. Dubovikov a,c

    E-Print Network [OSTI]

    Dynamical model of mesoscales in z-coordinates V.M. Canuto a,b,*, M.S. Dubovikov a,c a NASA Abstract Using the equations of the dynamical mesoscale model developed previously [Ocean Modell. (2004) 8, 1­ 30], we derive a mesoscale model in z-coordinates to be used in coarse resolution OGCMs. We

  11. Macroscale modeling and mesoscale observations of plasma density structures in the polar cap

    SciTech Connect (OSTI)

    Basu, S. [Phillips Lab., Hanscom Air Force Base, MA (United States)] [Phillips Lab., Hanscom Air Force Base, MA (United States); Basu, S. [National Science Foundation, Arlington, VA (United States)] [National Science Foundation, Arlington, VA (United States); Sojka, J.J. [Utah State Univ., Logan, UT (United States)] [and others] [Utah State Univ., Logan, UT (United States); and others

    1995-04-15

    The seasonal and UT variation of mesoscale structures (10 km - 100 m) in the central polar cap has been obtained from an analysis of 250-MHz intensity scintillation observations made at Thule, Greenland. It has been established earlier that mesoscale structures causing scintillations of satellite signals may develop at the edges of macroscale structures (several hundred km) such as discrete polar cap plasma density enhancements or patches through the gradient drift instability process. As such, the authors examined the seasonal and UT variation of polar cap patches simulated by using the USU Time Dependent Ionospheric Model (TDIM) under conditions of southward B{sub z}. A fairly remarkable similarity is found between the scintillation observations and the model predictions of patch occurrence. For instance, both the patch and scintillation occurrences are minimized during the winter solstice (northern hemisphere) between 0800-1200 UT while also having their largest seasonal intensity between 2000-2400 UT. Little UT dependence of patches and scintillations is seen at equinox with high intensity being observed throughout the day, while during local summer the intensity of macroscale patches and mesoscale irregularities are found to be a minimum at all UT. These results indicate that macroscale features in the polar cap are routinely associated with plasma instabilities giving rise to smaller scale structures and that the specific patch formation mechanism assumed in the simulation is consistent with the observations. This ability to bridge between macroscale modeling and mesoscale observations provides a natural framework for the modeling of mesoscale structures themselves. This mesoscale modeling, in turn, can be utilized in a variety of radar and communication systems applications in the polar region. 25 refs., 3 figs.

  12. Extended self-similarity of atmospheric boundary layer wind fields in mesoscale regime: Is it real?

    E-Print Network [OSTI]

    Kiliyanpilakkil, V P

    2015-01-01

    In this letter, we study the scaling properties of multi-year observed and atmospheric model-generated wind time series. We have found that the extended self-similarity holds for the observed series, and remarkably, the scaling exponents corresponding to the meoscale range closely match the well-accepted inertial-range turbulence values. However, the scaling results from the simulated time series are significantly different.

  13. Analysis and Simulation of a Meso-scale Model of Diffusive Resistance of Bacterial Biofilms to

    E-Print Network [OSTI]

    Demaret, Laurent

    Analysis and Simulation of a Meso-scale Model of Diffusive Resistance of Bacterial Biofilms Most bacteria live in biofilm communities, which offer protection against harmful external impacts mathematical model that focuses on the diffusive resistance that a growing biofilm exerts against penetration

  14. Buoyancy Effects on the Scaling Characteristics of Atmospheric Boundary Layer Wind Fields in the Mesoscale Range

    E-Print Network [OSTI]

    Kiliyanpilakkil, V P; Ruiz-Columbié, A; Araya, G; Castillo, L; Hirth, B; Burgett, W

    2015-01-01

    We have analyzed long-term wind speed time-series from five field sites up to a height of 300 m from the ground. Structure function-based scaling analysis has revealed that the scaling exponents in the mesoscale regime systematically depend on height. This anomalous behavior is shown to be caused by the buoyancy effects. In the framework of the extended self-similarity, the relative scaling exponents portray quasi-universal behavior.

  15. Steering in computational science: mesoscale modelling and J. CHIN{, J. HARTING{, S. JHA{, P. V. COVENEY{, A. R. PORTER{ and S. M. PICKLES{{

    E-Print Network [OSTI]

    Harting, Jens

    Steering in computational science: mesoscale modelling and simulation J. CHIN{, J. HARTING{, S. JHA steering for high performance computing applications. Lattice-Boltzmann mesoscale fluid simulations, there is currently considerable interest in mesoscale models. These models coarse grain most of the atomic

  16. 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

  17. Some Effects of Model Resolution on Simulated Gravity Waves Generated by Deep, Mesoscale Convection

    E-Print Network [OSTI]

    Knievel, Jason Clark

    Some Effects of Model Resolution on Simulated Gravity Waves Generated by Deep, Mesoscale Convection. Introduction Gravity waves generated by deep convective clouds play an important role in the momentum budget scales: short gravity waves generated by individual con- vective systems and cells on the meso- and meso

  18. 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]

    Chaboureau, Jean-Pierre

    Mesoscale model cloud scheme assessment using satellite observations Jean-Pierre Chaboureau, Jean of the mesoscale nonhydrostatic (Meso-NH) model has been conducted by comparing synthetic METEOSAT brightness combines the output from a bulk explicit cloud scheme routinely used in mesoscale simulations

  19. Mesoscale & Microscale Meteorological Division / NCAR WRF Nature Run

    E-Print Network [OSTI]

    Michalakes, John

    Mesoscale & Microscale Meteorological Division / NCAR WRF Nature Run John Michalakes Josh Hacker overview and petascale issues Nature run methodology Results and conclusion #12;Mesoscale & Microscale's atmosphere #12;Mesoscale & Microscale Meteorological Division / NCAR Description of Science · Kinetic energy

  20. A STUDY OF ICE ACCUMULATION AND STABILITY IN MARTIAN CRATERS UNDER PAST ORBITAL CONDITIONS USING THE LMD MESOSCALE MODEL. J.-B. Madeleine1

    E-Print Network [OSTI]

    Madeleine, Jean-Baptiste

    THE LMD MESOSCALE MODEL. J.-B. Madeleine1 , J. W. Head1 , A. Spiga2 , J. L. Dickson1 and F. Forget2 , 1 formed, using geolog- ical observations [e.g., 1-4] and mesoscale climate simulations [5 provide essential constraints on the mesoscale climate which prevailed during their formation

  1. MESO-SCALE MODELING OF THE INFLUENCE OF INTERGRANULAR GAS BUBBLES ON EFFECTIVE THERMAL CONDUCTIVITY

    SciTech Connect (OSTI)

    Paul C. Millett; Michael Tonks

    2011-06-01

    Using a mesoscale modeling approach, we have investigated how intergranular fission gas bubbles, as observed in high-burnup nuclear fuel, modify the effective thermal conductivity in a polycrystalline material. The calculations reveal that intergranular porosity has a significantly higher resistance to heat transfer compared to randomly-distributed porosity. A model is developed to describe this conductivity reduction that considers an effective grain boundary Kapitza resistance as a function of the fractional coverage of grain boundaries by bubbles.

  2. Automatic Parameter Estimation in a Mesoscale Model Without Ensembles

    E-Print Network [OSTI]

    Duane, Gregory S.

    . Hacker National Center for Atmospheric Research, Boulder, CO gduane,hacker@ucar.edu In numerical as extra state variables, and applying standard data assimilation methods that use ensembles to rep- resent, it is argued that the approach to parameter estimation can be extended to a more general scheme for machine

  3. Macroscale modeling and mesoscale observations of plasma density structures in the polar cap

    SciTech Connect (OSTI)

    Basu, S.; Basu, S.; Sojka, J.J.; Schunk, R.W.; MacKenzie, E.

    1995-04-15

    The seasonal and UT variation of mesoscale structures (10 km - 100 m) in the central polar cap has been obtained from an analysis of 250-MHz intensity scintillation observations made at Thule, Greenland. It has been established earlier that mesoscale structures causing scintillations of satellite signals may develop at the edges of macroscale structures (several hundred km) such as discrete polar cap plasma density enhancements or patches through the gradient drift instability process. As such, the authrs examined the seasonal and UT variation of polar cap patches simulated by using the USU Time Dependent Ionospheric Model (TDIM) under conditions of southward B(sub z). A fairly remarkable similarity is found between the scintillation observations and the model predictions of patch occurrence. For instance, both the patch and scintillation occurrences are minimized during the winter solstice (northern hemisphere) between 0800-1200 UT while also having their largest seasonal intensity between 2000-2400 UT. Little UT dependence of patches and scintillations is seen at equinox with high intensity being observed throughout the day, while during local summer the intensity of macroscale patches and mesoscale irregularities are found to be a minimum at all UT. These results indicate that macroscale features in the polar cap are routinely associated with plasma instabilities giving rise to smaller scale structures and that the specific patch formation mechanism assumed in the simulation is consistent with the observations.

  4. Coupling the high-complexity land surface model ACASA to the mesoscale model WRF

    E-Print Network [OSTI]

    Pyles, R. D.

    In this study, the Weather Research and Forecasting (WRF) model 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 ...

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

    E-Print Network [OSTI]

    Xu, L.

    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 ...

  6. Screening properties of four mesoscale smoothed charge models, with application to dissipative particle dynamics

    E-Print Network [OSTI]

    Patrick B. Warren; Andrey Vlasov

    2014-02-25

    We extend our previous study [J. Chem. Phys. 138, 204907 (2013)] to quantify the screening properties of four mesoscale smoothed charge models used in dissipative particle dynamics. Using a combination of the hypernetted chain integral equation closure and the random phase approximation, we identify regions where the models exhibit a real-valued screening length, and the extent to which this agrees with the Debye length in the physical system. We find that the second moment of the smoothed charge distribution is a good predictor of this behaviour. We are thus able to recommend a consistent set of parameters for the models.

  7. A wildland fire modeling and visualization environment , Jonathan D. Beezley

    E-Print Network [OSTI]

    Utah, University of

    : · The wildland fire simulation code SFIRE coupled with a mesoscale atmospheric simulation code, the Weather by the coupling of a mesoscale weather model with a simple 2D fire spread model (Clark et al. 1996a,b, 2004; Coen

  8. MESOSCALE CONVECTIVE SYSTEMS Robert A. Houze Jr.

    E-Print Network [OSTI]

    Houze Jr., Robert A.

    MESOSCALE CONVECTIVE SYSTEMS Robert A. Houze Jr. Department of Atmospheric Sciences University; published 31 December 2004. [1] Mesoscale convective systems (MCSs) have regions of both convective and stratiform precipitation, and they develop mesoscale circulations as they mature. The upward motion takes

  9. The lipid bilayer at the mesoscale: a physical continuum model

    E-Print Network [OSTI]

    Phillip L. Wilson; Huaxiong Huang; Shu Takagi

    2008-02-26

    We study a continuum model of the lipid bilayer based on minimizing the free energy of a mixture of water and lipid molecules. This paper extends previous work by Blom & Peletier (2004) in the following ways. (a) It formulates a more physical model of the hydrophobic effect to facilitate connections with microscale simulations. (b) It clarifies the meaning of the model parameters. (c) It outlines a method for determining parameter values so that physically-realistic bilayer density profiles can be obtained, for example for use in macroscale simulations. Points (a)-(c) suggest that the model has potential to robustly connect some micro- and macroscale levels of multiscale blood flow simulations. The mathematical modelling in point (a) is based upon a consideration of the underlying physics of inter-molecular forces. The governing equations thus obtained are minimized by gradient flows via a novel numerical approach; this enables point (b). The numerical results are shown to behave physically in terms of the effect of background concentration, in contrast to the earlier model which is shown here to not display the expected behaviour. A "short-tail" approximation of the lipid molecules also gives an analytical tool which yields critical values of some parameters under certain conditions. Point (c) involves the first quantitative comparison of the numerical data with physical experimental results.

  10. The Importance of Mesoscale Circulations Generated by SubgridScale Landscape Heterogeneities in General Circulations Models

    E-Print Network [OSTI]

    Fridlind, Ann

    jcl92c.tex The Importance of Mesoscale Circulations Generated by Subgrid­Scale Landscape Oceanography, Cook Campus, Rutgers University, New Brunswick, NJ 08903, USA. #12; Abstract A mesoscale. These results emphasize the need to parameterize mesoscale processes induced by landscape discontinuities

  11. Mesoscale modeling of phase transition dynamics of thermoresponsive polymers

    E-Print Network [OSTI]

    Li, Zhen; Li, Xuejin; Karniadakis, George Em

    2015-01-01

    We present a non-isothermal mesoscopic model for investigation of the phase transition dynamics of thermoresponsive polymers. Since this model conserves energy in the simulations, it is able to correctly capture not only the transient behavior of polymer precipitation from solvent, but also the energy variation associated with the phase transition process. Simulations provide dynamic details of the thermally induced phase transition and confirm two different mechanisms dominating the phase transition dynamics. A shift of endothermic peak with concentration is observed and the underlying mechanism is explored.

  12. Dynamic mesoscale model of dipolar fluids via fluctuating hydrodynamics

    SciTech Connect (OSTI)

    Persson, Rasmus A. X.; Chu, Jhih-Wei, E-mail: jwchu@nctu.edu.tw [Institute of Bioinformatics and Systems Biology, National Chiao Tung University, Hsinchu 30068, Taiwan (China); Department of Biological Science and Technology, National Chiao Tung University, Hsinchu 30068, Taiwan (China); Voulgarakis, Nikolaos K. [Department of Mathematics, Washington State University, Richland, Washington 99372 (United States)

    2014-11-07

    Fluctuating hydrodynamics (FHD) is a general framework of mesoscopic modeling and simulation based on conservational laws and constitutive equations of linear and nonlinear responses. However, explicit representation of electrical forces in FHD has yet to appear. In this work, we devised an Ansatz for the dynamics of dipole moment densities that is linked with the Poisson equation of the electrical potential ? in coupling to the other equations of FHD. The resulting ?-FHD equations then serve as a platform for integrating the essential forces, including electrostatics in addition to hydrodynamics, pressure-volume equation of state, surface tension, and solvent-particle interactions that govern the emergent behaviors of molecular systems at an intermediate scale. This unique merit of ?-FHD is illustrated by showing that the water dielectric function and ion hydration free energies in homogeneous and heterogenous systems can be captured accurately via the mesoscopic simulation. Furthermore, we show that the field variables of ?-FHD can be mapped from the trajectory of an all-atom molecular dynamics simulation such that model development and parametrization can be based on the information obtained at a finer-grained scale. With the aforementioned multiscale capabilities and a spatial resolution as high as 5 Å, the ?-FHD equations represent a useful semi-explicit solvent model for the modeling and simulation of complex systems, such as biomolecular machines and nanofluidics.

  13. Mesoscale Eddies in the Gulf of Alaska: Observations and Implications

    E-Print Network [OSTI]

    Rovegno, Peter

    2012-01-01

    Chao, Y. 2012. Modeling the mesoscale eddy field in the GulfShriver, J. F. 2001. Mesoscale variability in the boundaryof the Gulf of Alaska mesoscale circulation. Progress in

  14. Calibrated Probabilistic Mesoscale Weather Field Forecasting: The Geostatistical Output Perturbation

    E-Print Network [OSTI]

    Raftery, Adrian

    Calibrated Probabilistic Mesoscale Weather Field Forecasting: The Geostatistical Output. This is typically not feasible for mesoscale weather prediction carried out locally by organizations without by simulating realizations of the geostatistical model. The method is applied to 48-hour mesoscale forecasts

  15. Diagnosis of Ocean Mesoscale Eddy Tracer Fluxes

    E-Print Network [OSTI]

    Fox-Kemper, Baylor

    Diagnosis of Ocean Mesoscale Eddy Tracer Fluxes Baylor Fox-Kemper U. Colorado-Boulder, with Scott - 10,000 km, yrs->centuries) => resolved · Mesoscale variability (10 - 100 km, mo -> yrs) => resolved) => parameterized Boundary Layer Models Mesoscale resolving models Climate models Submesoscale variability Coupling

  16. A creep-damage model for mesoscale simulations of concrete expansion-degradation phenomena

    SciTech Connect (OSTI)

    Giorla, Alain B; Le Pape, Yann

    2015-01-01

    Long-term performance of aging concrete in nuclear power plants (NPPs) requires a careful examination of the physical phenomena taking place in the material. Concrete under high neutron irradiation is subjected to large irreversible deformations as well as mechanical damage, caused by a swelling of the aggregates. However, these results, generally obtained in accelerated conditions in test reactors, cannot be directly applied to NPP irradiated structures, i.e., the biological shield, operating conditions due to difference in time scale and environmental conditions (temperature, humidity). Mesoscale numerical simulations are performed to separate the underlying mechanisms and their interactions. The cement paste creep-damage model accounts for the effect of the loading rate on the apparent damage properties of the material and uses an event-based approach to capture the competition between creep and damage. The model is applied to the simulation of irradiation experiments from the literature and shows a good agreement with the experimental data.

  17. TENURE-TRACK FACULTY POSITION Mesoscale Meteorology

    E-Print Network [OSTI]

    Birner, Thomas

    TENURE-TRACK FACULTY POSITION ­ Mesoscale Meteorology Colorado State University The Department or associate level faculty position specializing in mesoscale meteorology. Exceptionally qualified candidates in linking models and/or theory with observations for the study of mesoscale processes. The successful

  18. Implementation and assessment of turbine wake models in the Weather Research and Forecasting model for both mesoscale and large-eddy simulation

    SciTech Connect (OSTI)

    Singer, M; Mirocha, J; Lundquist, J; Cleve, J

    2010-03-03

    Flow dynamics in large wind projects are influenced by the turbines located within. The turbine wakes, regions characterized by lower wind speeds and higher levels of turbulence than the surrounding free stream flow, can extend several rotor diameters downstream, and may meander and widen with increasing distance from the turbine. Turbine wakes can also reduce the power generated by downstream turbines and accelerate fatigue and damage to turbine components. An improved understanding of wake formation and transport within wind parks is essential for maximizing power output and increasing turbine lifespan. Moreover, the influence of wakes from large wind projects on neighboring wind farms, agricultural activities, and local climate are all areas of concern that can likewise be addressed by wake modeling. This work describes the formulation and application of an actuator disk model for studying flow dynamics of both individual turbines and arrays of turbines within wind projects. The actuator disk model is implemented in the Weather Research and Forecasting (WRF) model, which is an open-source atmospheric simulation code applicable to a wide range of scales, from mesoscale to large-eddy simulation. Preliminary results demonstrate the applicability of the actuator disk model within WRF to a moderately high-resolution large-eddy simulation study of a small array of turbines.

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

    E-Print Network [OSTI]

    Ismael Hernández-Carrasco; Vincent Rossi; Emilio Hernández-García; Veronique Garçon; Cristóbal López

    2013-11-05

    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.

  20. MOSE: a feasibility study for optical turbulence forecasts with the Meso-Nh mesoscale model to support AO facilities at ESO sites (Paranal and Armazones)

    E-Print Network [OSTI]

    Masciadri, E; 10.1117/12.925924

    2012-01-01

    We present very encouraging preliminary results obtained in the context of the MOSE project, an on-going study aiming at investigating the feasibility of the forecast of the optical turbulence and meteorological parameters (in the free atmosphere as well as in the boundary and surface layer) at Cerro Paranal (site of the Very Large Telescope - VLT) and Cerro Armazones (site of the European Extremely Large Telescope - E-ELT), both in Chile. The study employs the Meso-Nh atmospheric mesoscale model and aims at supplying a tool for optical turbulence forecasts to support the scheduling of the scientific programs and the use of AO facilities at the VLT and the E-ELT. In this study we take advantage of the huge amount of measurements performed so far at Paranal and Armazones by ESO and the TMT consortium in the context of the site selection for the E-ELT and the TMT to constraint/validate the model. A detailed analysis of the model performances in reproducing the atmospheric parameters (T, V, p, H, ...) near the g...

  1. The Power of Mesoscale Modeling... Mul$physics mesoscale simula$on provides a powerful tool for designing materials to

    E-Print Network [OSTI]

    Chen, Long-Qing

    , neutronics, geomechanics, reac+ve transport, microstructure modeling, computa+onal fluid in verba+m from Schwen, D., E. Mar/nez, and A. Caro, J. Nuclear Mater (cv) in UO2 fuel. Also shown are the switching func+on h, the order

  2. The Regional Atmospheric Modeling System (RAMS): Development for Parallel Processing Computer

    E-Print Network [OSTI]

    Cirne, Walfredo

    on the mesoscale (horizontal scales from 2 km to 2000 km) for purposes ranging from operational weather forecasting and simulating convective clouds, mesoscale convective systems, cirrus clouds, and precipitating weather systems models that had a great deal of overlap, the CSU cloud/mesoscale mode (Tripoli and Cotton, 1982

  3. Simulations of Clouds and Sensitivity Study by Weather Research and Forecast Model for Atmospheric Radiation Measurement Case 4

    SciTech Connect (OSTI)

    Wu, J.; Zhang, M.

    2005-03-18

    One of the large errors in general circulation models (GCMs) cloud simulations is from the mid-latitude, synoptic-scale frontal cloud systems. Now, with the availability of the cloud observations from Atmospheric Radiation Measurement (ARM) 2000 cloud Intensive Operational Period (IOP) and other observational datasets, the community is able to document the model biases in comparison with the observations and make progress in development of better cloud schemes in models. Xie et al. (2004) documented the errors in midlatitude frontal cloud simulations for ARM Case 4 by single-column models (SCMs) and cloud resolving models (CRMs). According to them, the errors in the model simulated cloud field might be caused by following reasons: (1) lacking of sub-grid scale variability; (2) lacking of organized mesoscale cyclonic advection of hydrometeors behind a moving cyclone which may play important role to generate the clouds there. Mesoscale model, however, can be used to better under stand these controls on the subgrid variability of clouds. Few studies have focused on applying mesoscale models to the forecasting of cloud properties. Weaver et al. (2004) used a mesoscale model RAMS to study the frontal clouds for ARM Case 4 and documented the dynamical controls on the sub-GCM-grid-scale cloud variability.

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

    E-Print Network [OSTI]

    Jochum, Markus

    horizontal SST gradients in the ocean, developing in response to the southwest monsoon winds. This summertime of the ocean. The observed relationship between the near-surface winds and mesoscale SSTs generate Ekman pump by seasonally reversing monsoonal winds, which drive an in- tense oceanic response off the coast of Africa

  5. Mesoscale simulation of polymer reaction equilibrium: Combining dissipative particle dynamics with reaction ensemble Monte Carlo.

    E-Print Network [OSTI]

    Lisal, Martin

    Mesoscale simulation of polymer reaction equilibrium: Combining dissipative particle dynamics a mesoscale simulation technique, called the reaction ensemble dissipative particle dynamics RxDPD method. Coarse-grained, particle- based mesoscale models that retain only the most essential features

  6. Effect of mesoscale topography over the Tibetan Plateau on summer precipitation in China: A regional model study

    E-Print Network [OSTI]

    Wang, Yuqing

    Effect of mesoscale topography over the Tibetan Plateau on summer precipitation in China 2008; accepted 27 August 2008; published 8 October 2008. [1] The effect of mesoscale topography over and topography. In the sensitivity simulation, the mesoscale feature in topography over the TP was smoothed out

  7. Simulation and characterization of the Adriatic Sea mesoscale variability

    E-Print Network [OSTI]

    Cushman-Roisin, Benoit

    Simulation and characterization of the Adriatic Sea mesoscale variability Benoit Cushman-Roisin,1 resolve the mesoscale variability because the grid size falls below the first baroclinic deformation in two larger-scale models. The present simulations demonstrate that the DieCAST model allows mesoscale

  8. Report on the use of stability parameters and mesoscale

    E-Print Network [OSTI]

    Report on the use of stability parameters and mesoscale modelling in short-term prediction Jake Nielsen, Henrik Madsen, John Tøfting Title: Report on the use of stability parameters and mesoscale. Mesoscale modelling has been carried out using KAMM at this location. The characteristics of the measured

  9. Penetrative turbulence associated with mesoscale surface heat flux variations

    E-Print Network [OSTI]

    Alam, Jahrul M

    2015-01-01

    This article investigates penetrative turbulence in the atmospheric boundary layer. Using a large eddy simulation approach, we study characteristics of the mixed layer with respect to surface heat flux variations in the range from 231.48 W/m$^2$ to 925.92 W/m$^2$, and observe that the surface heterogeneity on a spatial scale of $20$ km leads to downscale turbulent kinetic energy cascade. Coherent fluctuations of mesoscale horizontal wind is observed at 100m above the ground. Such a surface induced temporal oscillations in the horizontal wind suggest a rapid jump in mesocale wind forecasts, which is difficult to parameterize using traditional one-dimensional ensemble-mean models. Although the present work is idealized at a typical scale (20km) of surface heterogeneity, the results help develop effective subgrid scale parameterization schemes for classical weather forecasting mesoscale models.

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

    SciTech Connect (OSTI)

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

    2004-07-01

    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.

  11. CORIOLIS EFFECTS IN MESOSCALE SHALLOW LAYER FLOWS J. C. R. Hunt

    E-Print Network [OSTI]

    Hunt, Julian

    CORIOLIS EFFECTS IN MESOSCALE SHALLOW LAYER FLOWS J. C. R. Hunt ¢¡ £ ,A. Orr , D. Cresswell layer or inversion layer, is developed for idealised and steady, but typical, mesoscale atmospheric estimates for a wide range of perturbed mesoscale flows, especially where the surface conditions change

  12. Elements of comparison between Martian and terrestrial mesoscale meteorological phenomena: Katabatic winds and boundary layer convection

    E-Print Network [OSTI]

    Spiga, Aymeric

    Elements of comparison between Martian and terrestrial mesoscale meteorological phenomena Keywords: Mesoscale meteorology Katabatic winds Boundary layer convection Comparative planetology a b s t r a c t Terrestrial and Martian atmospheres are both characterised by a large variety of mesoscale

  13. MESOSCALE ANALYSIS OF A CAROLINA COASTAL FRONT SETHU RAMAN, NEERAJA C. REDDY and DEVDUTTA S. NIYOGI

    E-Print Network [OSTI]

    Niyogi, Dev

    MESOSCALE ANALYSIS OF A CAROLINA COASTAL FRONT SETHU RAMAN, NEERAJA C. REDDY and DEVDUTTA S. NIYOGI the shore. Key words: GALE, Coastal front, Atmospheric boundary layer, Gulf Stream, Mesoscale analysis turbulent heat fluxes. These strong gradients in heat fluxes enhance mesoscale circulation

  14. A Community Atmosphere Model with Superparameterized Clouds

    SciTech Connect (OSTI)

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

    2013-06-18

    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.

  15. 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)

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

    2013-03-14

    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

  16. MOSE: zooming on the Meso-NH mesoscale model performances at the surface layer at ESO sites (Paranal and Armazones)

    E-Print Network [OSTI]

    Lascaux, Franck; di Arcetri, INAF / Osservatorio Astrofisico; 10.1117/12.925934

    2012-01-01

    In the context of the MOSE project, in this contribution we present a detailed analysis of the Meso-NH mesoscale model performances and their dependency on the model and orography horizontal resolutions in proximity of the ground. The investigated sites are Cerro Paranal (site of the ESO Very Large Telescope - VLT) and Cerro Armazones (site of the ESO European Extremely Large Telescope - E-ELT), in Chile. At both sites, data from a rich statistical sample of different nights are available - from AWS (Automated Weather Stations) and masts - giving access to wind speed, wind direction and temperature at different levels near the ground (from 2 m to 30 m above the ground). In this study we discuss the use of a very high horizontal resolution (dX=0.1 km) numerical configuration that overcomes some specific limitations put in evidence with a standard configuration with dX=0.5 km. In both sites results are very promising. The study is co-funded by ESO and INAF.

  17. Mixed Layer Mesoscales for OGCMs: Model development and assessment with T/P, WOCE and Drifter data

    E-Print Network [OSTI]

    Canuto, V M; Leboissetier, A

    2011-01-01

    We present a model for mixed layer (ML) mesoscale (M) fluxes of an arbitrary tracer in terms of the resolved fields (mean tracer and mean velocity). The treatment of an arbitrary tracer, rather than only buoyancy, is necessary since OGCMs time step T, S, CO2, etc and not buoyancy. The particular case of buoyancy is used to assess the model results. The paper contains three parts: derivation of the results, discussion of the results and assessment of the latter using, among others, WOCE, T/P and Drifter data. Derivation. To construct the M fluxes, we first solve the ML M dynamic equations for the velocity and tracer M fields. The goal of the derivation is to emphasize the different treatments of the non-linear terms in the adiabatic vs. diabatic ocean (deep ocean vs. mixed layer). Results. We derive analytic expressions for the following variables: a) vertical and horizontal M fluxes of an arbitrary tracer, b) M diffusivity in terms of the EKE, c) surface value of the EKE in terms of the vertical M buoyancy fl...

  18. Search for: mesoscale | DOE PAGES

    Office of Scientific and Technical Information (OSTI)

    mesoscale Find + Advanced Search Advanced Search All Fields: mesoscale Title: Full Text: Bibliographic Data: Creator Author: Name Name ORCID Search Authors Type: All Accepted...

  19. SciTech Connect: mesoscale

    Office of Scientific and Technical Information (OSTI)

    mesoscale Find + Advanced Search Term Search Semantic Search Advanced Search All Fields: mesoscale Semantic Semantic Term Title: Full Text: Bibliographic Data: Creator Author:...

  20. From deterministic to stochastic, from mesoscale to macroscopic

    E-Print Network [OSTI]

    Title: From deterministic to stochastic, from mesoscale to macroscopic: multiscale modeling of grain growth Abstract: Many problems in science and engineering ...

  1. Atmospheric Environment ] (

    E-Print Network [OSTI]

    Bornstein, Robert

    Mesoscale Model (CSUMM) to simulate summertime flows in SoCAB. Simulated daytime onshore, upslope winds were-consistent wind model of Douglas and Kessler (1991) used SCCCAMP data to analyze SoCAB mesoscale flow patterns input into the photochemical Urban Airshed Model (UAM). Results showed that an increased albedo lowered

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

    E-Print Network [OSTI]

    Reich, Brian J.

    values. We use spatial logistic regression to model the probability of rain for both sources of data modelling, spatial logistic regression, spatial temporal models. 1 #12;and allows the temporal evolution detailed spatial structure of rain fields is costly and their maintenance is time-consuming. Remote sensing

  3. Urban and land surface effects on the 30 July 2003 mesoscale convective system event observed in the southern Great Plains

    E-Print Network [OSTI]

    Niyogi, Dev

    Urban and land surface effects on the 30 July 2003 mesoscale convective system event observed/Atmosphere Mesoscale Prediction System (COAMPS 1 ) to investigate the impact of urban and land vegetation processes on the prediction of the mesoscale convective system (MCS) observed on 30 July 2003 in the vicinity of Oklahoma City

  4. Simulating the Transition from Drizzling Marine Stratocumulus to Boundary Layer Cumulus with a Mesoscale Model

    E-Print Network [OSTI]

    Mechem, David B.; Kogan, Yefim L.

    2003-10-01

    variability is analogous to the drizzle-induced cloud breakup produced in large eddy simulation studies. The dynamics of the pure stratocumulus cloud are dictated by the model's subgrid parameterization, while the more convective regime exhibits appreciable...

  5. The reduction of biological production induced by mesoscale mixing: a modelling study in the Benguela upwelling

    E-Print Network [OSTI]

    Hernández-Carrasco, Ismael; Hernández-García, Emilio; Garçon, Veronique; López, Cristóbal

    2013-01-01

    Recent studies, both based on remote sensed data and coupled models, showed a reduction of biological productivity due to vigorous horizontal mixing in upwelling systems. In order to better understand this phenomenon, we have considered a system of oceanic flow in 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 computed 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 seems to be the dominant process involved. In the northern area, other factors not taken into account in our simulation are influencing the ecosyst...

  6. Simulation of Indentation Fracture in Crystalline Materials Using Mesoscale Self-Assembly

    E-Print Network [OSTI]

    Hutchinson, John W.

    Simulation of Indentation Fracture in Crystalline Materials Using Mesoscale Self-Assembly Venkat R Abstract: A new physical model based on mesoscale self-assembly is developed to simulate indentation

  7. Mesoscale Phase-Field Modeling of Charge Transport in Nanocomposite Electrodes for Lithium-ion Batteries

    SciTech Connect (OSTI)

    Hu, Shenyang Y.; Li, Yulan; Rosso, Kevin M.; Sushko, Maria L.

    2013-01-10

    A phase-field model is developed to investigate the influence of microstructure, thermodynamic and kinetic properties, and charging conditions on charged particle transport in nanocomposite electrodes. Two sets of field variables are used to describe the microstructure. One is comprised of the order parameters describing size, orientation and spatial distributions of nanoparticles, and the other is comprised of the concentrations of mobile species. A porous nanoparticle microstructure filled with electrolyte is taken as a model system to test the phase-field model. Inhomogeneous and anisotropic dielectric constants and mobilities of charged particles, and stresses associated with lattice deformation due to Li-ion insertion/extraction are considered in the model. Iteration methods are used to find the elastic and electric fields in an elastically and electrically inhomogeneous medium. The results demonstrate that the model is capable of predicting charge separation associated with the formation of a double layer at the electrochemical interface between solid and electrolyte, and the effect of microstructure, inhomogeneous and anisotropic thermodynamic and kinetic properties, charge rates, and stresses on voltage versus current density and capacity during charging and discharging.

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

    E-Print Network [OSTI]

    Menon, Govind

    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

  9. Fluid-particle flow modelling and validation using two-way-coupled mesoscale SPH-DEM

    E-Print Network [OSTI]

    Robinson, Martin; Ramaioli, Marco

    2013-01-01

    We present a meshless simulation method for multiphase fluid-particle flows coupling Smoothed Particle Hydrodynamics (SPH) and the Discrete Element Method (DEM). Rather than fully resolving the interstitial fluid, which is often infeasible, the unresolved fluid model is based on the locally averaged Navier Stokes equations, which are coupled with a DEM model for the solid phase. In contrast to similar mesh-based Discrete Particle Methods (DPMs), this is a purely particle-based method and enjoys the flexibility that comes from the lack of a prescribed mesh. It is suitable for problems such as free surface flow or flow around complex, moving and/or intermeshed geometries. It can be used for both one and two-way coupling and is applicable to both dilute and dense particle flows. A comprehensive validation procedure for fluid-particle simulations is presented and applied to the SPH-DEM method, using simulations of single and multiple particle sedimentation in a 3D fluid column and comparison with analytical model...

  10. Lipid-Based Nanodiscs as Models for Studying Mesoscale Coalescence A Transport Limited Case

    SciTech Connect (OSTI)

    Hu, Andrew; Fan, Tai-Hsi; Katsaras, John; Xia, Yan; Li, Ming; Nieh, Mu-Ping

    2014-01-01

    Lipid-based nanodiscs (bicelles) are able to form in mixtures of long- and short-chain lipids. Initially, they are of uniform size but grow upon dilution. Previously, nanodisc growth kinetics have been studied using time-resolved small angle neutron scattering (SANS), a technique which is not well suited for probing their change in size immediately after dilution. To address this, we have used dynamic light scattering (DLS), a technique which permits the collection of useful data in a short span of time after dilution of the system. The DLS data indicate that the negatively charged lipids in nanodiscs play a significant role in disc stability and growth. Specifically, the charged lipids are most likely drawn out from the nanodiscs into solution, thereby reducing interparticle repulsion and enabling the discs to grow. We describe a population balance model, which takes into account Coulombic interactions and adequately predicts the initial growth of nanodiscs with a single parameter i.e., surface potential. The results presented here strongly support the notion that the disc coalescence rate strongly depends on nanoparticle charge density. The present system containing low-polydispersity lipid nanodiscs serves as a good model for understanding how charged discoidal micelles coalesce.

  11. Atmospheric transmittance model for photosynthetically active radiation

    SciTech Connect (OSTI)

    Paulescu, Marius; Stefu, Nicoleta; Gravila, Paul; Paulescu, Eugenia; Boata, Remus; Pacurar, Angel; Mares, Oana; Pop, Nicolina; Calinoiu, Delia

    2013-11-13

    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, Ångström'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.

  12. Mesoscale ensemble-based data assimilation and parameter estimation 

    E-Print Network [OSTI]

    Aksoy, Altug

    2005-11-01

    -1 MESOSCALE ENSEMBLE-BASED DATA ASSIMILATION AND PARAMETER ESTIMATION A Dissertation by ALTUG AKSOY Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of DOCTOR... OF PHILOSOPHY August 2005 Major Subject: Atmospheric Sciences MESOSCALE ENSEMBLE-BASED DATA ASSIMILATION AND PARAMETER ESTIMATION A Dissertation by ALTUG AKSOY Submitted to the Office of Graduate Studies of Texas A...

  13. Distribution and Habitat Associations of Billfish and Swordfish Larvae across Mesoscale Features in the Gulf

    E-Print Network [OSTI]

    Rooker, Jay R.

    Distribution and Habitat Associations of Billfish and Swordfish Larvae across Mesoscale Features additive models (GAMs). Mesoscale features in the NGoM affected the distribution and abundance of billfish and Swordfish Larvae across Mesoscale Features in the Gulf of Mexico. PLoS ONE 7(4): e34180. doi:10.1371/journal

  14. Mesoscale-resolving simulations of summer and winter bora events in the Adriatic Sea

    E-Print Network [OSTI]

    Cushman-Roisin, Benoit

    Mesoscale-resolving simulations of summer and winter bora events in the Adriatic Sea Benoit CushmanCAST model on a 1.2-min grid (about 2-km resolution) and resolve the mesoscale variability because the grid-Roisin, B., and K. A. Korotenko (2007), Mesoscale-resolving simulations of summer and winter bora events

  15. AcceptedArticleThe effect of moist convection on thermally induced mesoscale circulations

    E-Print Network [OSTI]

    Gentine, Pierre

    AcceptedArticleThe effect of moist convection on thermally induced mesoscale circulations Malte of thermally induced mesoscale circulations rests primarily on observations and model studies of dry convection-eddy simulations are used to investigate the effect of moist convection on an idealized mesoscale circulation

  16. CONVERGENCE AND STABILITY IN UPSCALING OF FLOW WITH INERTIA FROM PORESCALE TO MESOSCALE

    E-Print Network [OSTI]

    Peszynska, Malgorzata

    CONVERGENCE AND STABILITY IN UPSCALING OF FLOW WITH INERTIA FROM PORESCALE TO MESOSCALE MAl with inertia from porescale (microscale) to Darcy scale (lab scale, mesoscale). In particular, we solve Navier-Darcy model with inertia at mesoscale. 1. Introduction. In [1] we presented a proof-of-concept algorithm

  17. Large-Scale Errors and Mesoscale Predictability in Pacific Northwest Snowstorms DALE R. DURRAN

    E-Print Network [OSTI]

    Large-Scale Errors and Mesoscale Predictability in Pacific Northwest Snowstorms DALE R. DURRAN The development of mesoscale numerical weather prediction (NWP) models over the last two decades has made- search communities. Nevertheless, the predictability of the mesoscale features captured in such forecasts

  18. Nesting large-eddy simulations within mesoscale simulations for wind energy applications

    SciTech Connect (OSTI)

    Lundquist, J K; Mirocha, J D; Chow, F K; Kosovic, B; Lundquist, K A

    2008-09-08

    With increasing demand for more accurate atmospheric simulations for wind turbine micrositing, for operational wind power forecasting, and for more reliable turbine design, simulations of atmospheric flow with resolution of tens of meters or higher are required. These time-dependent large-eddy simulations (LES), which resolve individual atmospheric eddies on length scales smaller than turbine blades and account for complex terrain, are possible with a range of commercial and open-source software, including the Weather Research and Forecasting (WRF) model. In addition to 'local' sources of turbulence within an LES domain, changing weather conditions outside the domain can also affect flow, suggesting that a mesoscale model provide boundary conditions to the large-eddy simulations. Nesting a large-eddy simulation within a mesoscale model requires nuanced representations of turbulence. Our group has improved the Weather and Research Forecasting model's (WRF) LES capability by implementing the Nonlinear Backscatter and Anisotropy (NBA) subfilter stress model following Kosovic (1997) and an explicit filtering and reconstruction technique to compute the Resolvable Subfilter-Scale (RSFS) stresses (following Chow et al, 2005). We have also implemented an immersed boundary method (IBM) in WRF to accommodate complex terrain. These new models improve WRF's LES capabilities over complex terrain and in stable atmospheric conditions. We demonstrate approaches to nesting LES within a mesoscale simulation for farms of wind turbines in hilly regions. Results are sensitive to the nesting method, indicating that care must be taken to provide appropriate boundary conditions, and to allow adequate spin-up of turbulence in the LES domain.

  19. MESOSCALE DESCRIPTION OF DEFECTED MATERIALS

    E-Print Network [OSTI]

    Vinals, Jorge

    MESOSCALE DESCRIPTION OF DEFECTED MATERIALS Jorge Vi~nals School of Physics and Astronomy. Laughlin) Small but finite wavenumber and finite frequency ("mesoscale") response functions and transport;MESOSCALE DESCRIPTION B B B B B B B A B A B A A B B A A A A BB A B Microscopic Mesoscopic Macroscopic vn

  20. Mesoscale Dynamics Spring Semester 2014

    E-Print Network [OSTI]

    Collett Jr., Jeffrey L.

    ATS 735 Mesoscale Dynamics (3 cr) Spring Semester 2014 Instructor: Richard H. Johnson, Room ATS 305: There are no required texts. The recent book Mesoscale Meteorology in Midlatitudes by Markowski and Richardson covers with mesoscale-related research. A set of notes will be made available for the course, although we will not cover

  1. Mesoscale Dynamics Spring Semester 2012

    E-Print Network [OSTI]

    Birner, Thomas

    ATS 735 Mesoscale Dynamics (3 cr) Spring Semester 2012 Instructor: Richard H. Johnson, Room ATS 305: There are no required texts. The recent book Mesoscale Meteorology in Midlatitudes by Markowski and Richardson covers with mesoscale-related research. A set of notes will be made available for the course, although we will not cover

  2. 7, 1043910465, 2007 Mesoscale inversion

    E-Print Network [OSTI]

    Boyer, Edmond

    ACPD 7, 10439­10465, 2007 Mesoscale inversion T. Lauvaux et al. Title Page Abstract Introduction Discussions Mesoscale inversion: first results from the CERES campaign with synthetic data T. Lauvaux 1,2 , M.lauvaux@lsce.ipsl.fr) 10439 #12;ACPD 7, 10439­10465, 2007 Mesoscale inversion T. Lauvaux et al. Title Page Abstract

  3. Seabird associations with mesoscale eddies: the subtropical Indian Ocean

    E-Print Network [OSTI]

    Hyrenbach, KD; Veit, RR; Weimerskirch, H; Jr, HGL

    2006-01-01

    Seabird associations with mesoscale eddies: the subtropicalsur- hydrographic fronts and mesoscale eddies (Haney & veyedclimatologies. J Clim mesoscale variability across ocean

  4. Aeras: A next generation global atmosphere model

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Spotz, William F.; Smith, Thomas M.; Demeshko, Irina P.; Fike, Jeffrey A.

    2015-06-01

    Sandia National Laboratories is developing a new global atmosphere model named Aeras that is performance portable and supports the quantification of uncertainties. These next-generation capabilities are enabled by building Aeras on top of Albany, a code base that supports the rapid development of scientific application codes while leveraging Sandia's foundational mathematics and computer science packages in Trilinos and Dakota. Embedded uncertainty quantification (UQ) is an original design capability of Albany, and performance portability is a recent upgrade. Other required features, such as shell-type elements, spectral elements, efficient explicit and semi-implicit time-stepping, transient sensitivity analysis, and concurrent ensembles, were not componentsmore »of Albany as the project began, and have been (or are being) added by the Aeras team. We present early UQ and performance portability results for the shallow water equations.« less

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

    SciTech Connect (OSTI)

    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.

    2011-10-31

    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.

  6. 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)

    Houze, Jr., Robert A.

    2013-11-13

    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.

  7. Generated using version 3.2 of the official AMS LATEX template Mesoscale Predictability and Initial-Condition Error Growth in1

    E-Print Network [OSTI]

    Generated using version 3.2 of the official AMS LATEX template Mesoscale Predictability and Initial;ABSTRACT5 Early investigations suggested that mesoscale atmospheric motions would have very limited6 cascade. In contrast, subsequent studies proposed that many mesoscale cir-8 culations inherit

  8. Q. J. R. Meteorol. Soc. (2006), 132, pp. 709736 doi: 10.1256/qj.04.141 Momentum transport processes in the stratiform regions of mesoscale

    E-Print Network [OSTI]

    Houze Jr., Robert A.

    2006-01-01

    processes in the stratiform regions of mesoscale convective systems over the western Pacific warm pool By DAVID B. MECHEM1, SHUYI S. CHEN2 and ROBERT A. HOUZE, Jr.3 1Cooperative Institute for Mesoscale of mesoscale convective systems (MCSs) during the Tropical Ocean­Global Atmosphere Coupled Ocean

  9. HIGH-RESOLUTION ATMOSPHERIC ENSEMBLE MODELING AT SRNL

    SciTech Connect (OSTI)

    Buckley, R.; Werth, D.; Chiswell, S.; Etherton, B.

    2011-05-10

    The High-Resolution Mid-Atlantic Forecasting Ensemble (HME) is a federated effort to improve operational forecasts related to precipitation, convection and boundary layer evolution, and fire weather utilizing data and computing resources from a diverse group of cooperating institutions in order to create a mesoscale ensemble from independent members. Collaborating organizations involved in the project include universities, National Weather Service offices, and national laboratories, including the Savannah River National Laboratory (SRNL). The ensemble system is produced from an overlapping numerical weather prediction model domain and parameter subsets provided by each contributing member. The coordination, synthesis, and dissemination of the ensemble information are performed by the Renaissance Computing Institute (RENCI) at the University of North Carolina-Chapel Hill. This paper discusses background related to the HME effort, SRNL participation, and example results available from the RENCI website.

  10. Mesoscale hybrid calibration artifact

    SciTech Connect (OSTI)

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

    2010-09-07

    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.

  11. Chapter 8: Modelling Sediment Records of Atmospherically Deposited Contaminants

    E-Print Network [OSTI]

    Short, Daniel

    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

  12. MESOSCALE SIMULATIONS OF POWDER COMPACTION

    SciTech Connect (OSTI)

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

    2009-12-28

    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.

  13. Mesoscale Simulations of Coarsening in GB Networks

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

    Mukul Kumar is the Principal Investigator for Mesoscale Simulations of Coarsening in GB Networks LLNL BES Programs Highlight Mesoscale Simulations of Coarsening in GB Networks The...

  14. Spatial Intermittency of Surface Layer Wind Fluctuations at Mesoscale Range Rachel Baile* and Jean-Francois Muzy

    E-Print Network [OSTI]

    Boyer, Edmond

    Spatial Intermittency of Surface Layer Wind Fluctuations at Mesoscale Range Rachel Bai¨le* and Jean and to confirm an intermittent nature of mesoscale fluctuations similar to the one observed in fully developed involving a wide range of spatiotemporal scales. The modeling of wind speed behavior in the mesoscale range

  15. Mesoscale variability in time series data: Satellite-based estimates for the U.S. JGOFS Bermuda Atlantic

    E-Print Network [OSTI]

    Mesoscale variability in time series data: Satellite-based estimates for the U.S. JGOFS Bermuda TOPEX/Poseidon­ERS-1/2) are used to characterize, statistically, the mesoscale variability about the U to better understand the contribution of mesoscale eddies to the time series record and the model- data

  16. Sensitivity of Mesoscale Gravity Waves to the Baroclinicity of Jet-Front Systems SHUGUANG WANG AND FUQING ZHANG

    E-Print Network [OSTI]

    Sensitivity of Mesoscale Gravity Waves to the Baroclinicity of Jet-Front Systems SHUGUANG WANG of mesoscale gravity waves to the baroclinicity of the background jet-front systems by simulating different life cycles of baroclinic waves with a high-resolution mesoscale model. Four simulations are made

  17. Atmospheric Chemistry, Modeling, and Biogeochemistry of Mercury

    E-Print Network [OSTI]

    activities that release mercury to the atmosphere include coal burning, industrial processes, waste incine and climate projections; critically and quantitatively analyze environmental management and policy proposals mercury research. Global Budget of Mercury Prior to the onset of human industrial activities, the amount

  18. On Adaptive Mesh Refinement for Atmospheric Pollution Models

    E-Print Network [OSTI]

    Sandu, Adrian

    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

  19. Computer support to run models of the atmosphere. Final report

    SciTech Connect (OSTI)

    Fung, I.

    1996-08-30

    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.

  20. Atmospheric Tides in the Latest Generation of Climate Models

    E-Print Network [OSTI]

    Covey, Curt

    For atmospheric tides driven by solar heating, the database of climate model output used in the most recent assessment report of the Intergovernmental Panel on Climate Change (IPCC) confirms and extends the authors’ earlier ...

  1. METR 4433, Mesoscale Meteorology Spring 2011

    E-Print Network [OSTI]

    Droegemeier, Kelvin K.

    METR 4433, Mesoscale Meteorology Spring 2011 Instructor Dr. Kelvin K. Droegemeier Office: Three, 1:00 ­ 2:30 pm Required Text Markowski, P. and Y. Richardson: Mesoscale Meteorology in Midlatitudes and physical analysis techniques to mesoscale phenomena. Topics include definition of the term "mesoscale

  2. ATS 641: Mesoscale Meteorology Spring 2014

    E-Print Network [OSTI]

    ATS 641: Mesoscale Meteorology Spring 2014 TR, 1:00-2:50 PM, ATS Room 101 Course Description and Prerequisites This course will cover the theory and application of mesoscale meteorology, and how mesoscale, students will be able to: · Describe the basic theories describing mesoscale weather phenomena · Understand

  3. METR 4433, Mesoscale Meteorology Spring 2013

    E-Print Network [OSTI]

    Droegemeier, Kelvin K.

    METR 4433, Mesoscale Meteorology Spring 2013 Instructor Dr. Kelvin K. Droegemeier (kkd Text Markowski, P. and Y. Richardson: Mesoscale Meteorology in Midlatitudes. Wiley-Blackwell, 430pp to mesoscale phenomena. Topics include definition of the term "mesoscale," radar principles and interpretation

  4. ANALYTICAL MODELS OF EXOPLANETARY ATMOSPHERES. I. ATMOSPHERIC DYNAMICS VIA THE SHALLOW WATER SYSTEM

    SciTech Connect (OSTI)

    Heng, Kevin; Workman, Jared E-mail: jworkman@coloradomesa.edu

    2014-08-01

    Within the context of exoplanetary atmospheres, we present a comprehensive linear analysis of forced, damped, magnetized shallow water systems, exploring the effects of dimensionality, geometry (Cartesian, pseudo-spherical, and spherical), rotation, magnetic tension, and hydrodynamic and magnetic sources of friction. Across a broad range of conditions, we find that the key governing equation for atmospheres and quantum harmonic oscillators are identical, even when forcing (stellar irradiation), sources of friction (molecular viscosity, Rayleigh drag, and magnetic drag), and magnetic tension are included. The global atmospheric structure is largely controlled by a single key parameter that involves the Rossby and Prandtl numbers. This near-universality breaks down when either molecular viscosity or magnetic drag acts non-uniformly across latitude or a poloidal magnetic field is present, suggesting that these effects will introduce qualitative changes to the familiar chevron-shaped feature witnessed in simulations of atmospheric circulation. We also find that hydrodynamic and magnetic sources of friction have dissimilar phase signatures and affect the flow in fundamentally different ways, implying that using Rayleigh drag to mimic magnetic drag is inaccurate. We exhaustively lay down the theoretical formalism (dispersion relations, governing equations, and time-dependent wave solutions) for a broad suite of models. In all situations, we derive the steady state of an atmosphere, which is relevant to interpreting infrared phase and eclipse maps of exoplanetary atmospheres. We elucidate a pinching effect that confines the atmospheric structure to be near the equator. Our suite of analytical models may be used to develop decisively physical intuition and as a reference point for three-dimensional magnetohydrodynamic simulations of atmospheric circulation.

  5. Mesoscale and Large-Eddy Simulations for Wind Energy

    SciTech Connect (OSTI)

    Marjanovic, N

    2011-02-22

    Operational wind power forecasting, turbine micrositing, and turbine design require high-resolution simulations of atmospheric flow over complex terrain. The use of both Reynolds-Averaged Navier Stokes (RANS) and large-eddy (LES) simulations is explored for wind energy applications using the Weather Research and Forecasting (WRF) model. To adequately resolve terrain and turbulence in the atmospheric boundary layer, grid nesting is used to refine the grid from mesoscale to finer scales. This paper examines the performance of the grid nesting configuration, turbulence closures, and resolution (up to as fine as 100 m horizontal spacing) for simulations of synoptically and locally driven wind ramping events at a West Coast North American wind farm. Interestingly, little improvement is found when using higher resolution simulations or better resolved turbulence closures in comparison to observation data available for this particular site. This is true for week-long simulations as well, where finer resolution runs show only small changes in the distribution of wind speeds or turbulence intensities. It appears that the relatively simple topography of this site is adequately resolved by all model grids (even as coarse as 2.7 km) so that all resolutions are able to model the physics at similar accuracy. The accuracy of the results is shown in this paper to be more dependent on the parameterization of the land-surface characteristics such as soil moisture rather than on grid resolution.

  6. Mesoscale Coupled Ocean-Atmosphere Interaction

    E-Print Network [OSTI]

    Seo, Hyodae

    2007-01-01

    curl) and downwind (crosswind) SST gradient, similar to theal. (2001). Downwind and crosswind SST gradient are computedcurl) and downwind (crosswind) SST gradient appear to be

  7. Mesoscale coupled ocean-atmosphere interaction

    E-Print Network [OSTI]

    Seo, Hyodae

    2007-01-01

    curl) and downwind (crosswind) SST gradient, similar to theal. (2001). Downwind and crosswind SST gradient are computedcurl) and downwind (crosswind) SST gradient appear to be

  8. Mesoscale coupled ocean-atmosphere interaction

    E-Print Network [OSTI]

    Seo, Hyodae

    2007-01-01

    surface currents on wind stress, heat flux, and wind powerflux components (wind stress, heat flux and fresh-waterWest Coast Surface Heat Fluxes, Wind Stress, and Wind Stress

  9. Mesoscale Coupled Ocean-Atmosphere Interaction

    E-Print Network [OSTI]

    Seo, Hyodae

    2007-01-01

    surface currents on wind stress, heat flux, and wind powerflux components (wind stress, heat flux and fresh-waterWest Coast Surface Heat Fluxes, Wind Stress, and Wind Stress

  10. Mesoscale coupled ocean-atmosphere interaction

    E-Print Network [OSTI]

    Seo, Hyodae

    2007-01-01

    coastal ocean to strong offshore winds: With application toand R. L. Smith, 1995: Offshore wind forcing in the Gulf ofwind stress maximum and CCS SST front located roughly 200 km further offshore

  11. Mesoscale Coupled Ocean-Atmosphere Interaction

    E-Print Network [OSTI]

    Seo, Hyodae

    2007-01-01

    coastal ocean to strong offshore winds: With application toand R. L. Smith, 1995: Offshore wind forcing in the Gulf ofwind stress maximum and CCS SST front located roughly 200 km further offshore

  12. Mesoscale Coupled Ocean-Atmosphere Interaction

    E-Print Network [OSTI]

    Seo, Hyodae

    2007-01-01

    Offshore wind forcing in the Gulf of Tehuantepec, Mexico:low-level winds blowing from the Gulf of Mexico and theover the Gulf of Mexico. The gap-forced wind jets are well

  13. Mesoscale coupled ocean-atmosphere interaction

    E-Print Network [OSTI]

    Seo, Hyodae

    2007-01-01

    Offshore wind forcing in the Gulf of Tehuantepec, Mexico:low-level winds blowing from the Gulf of Mexico and theover the Gulf of Mexico. The gap-forced wind jets are well

  14. Evaluation of the Atmospheric Transport Model in the MACCS2 Code...

    Office of Environmental Management (EM)

    Terrain effects (CALPUFF) Gaussian Plume Model Lagrangian Puff Model Turbulence Characterization - Atmospheric Stability Classical GP models use a classification...

  15. Adaptive Grids for Atmospheric General Circulation Models

    E-Print Network [OSTI]

    Jablonowski, Christiane

    the wind speed OMEGA model Courtesy of A. Sarma (SAIC, NC, USA) #12;Two Adaptive Shallow Water Models AMR the vertical resolutions adds another factor of 2 We need to increase our computational power by a factor

  16. The role of land surface processes on the mesoscale simulation of the July 26, 2005 heavy rain event over Mumbai, India

    E-Print Network [OSTI]

    Niyogi, Dev

    The role of land surface processes on the mesoscale simulation of the July 26, 2005 heavy rain Mesoscale convection Weather research and forecast model Indian summer monsoon Land surface processes

  17. Bull. Disas. Prey. Res. Inst., Kyoto Univ., Vol. 45, Part 2,3 No 390, February, 1996 39 Mesoscale Numerical Study over the HEIFE Area

    E-Print Network [OSTI]

    Takada, Shoji

    Mesoscale Numerical Study over the HEIFE Area Part 1: Three Dimensional Wind Field By Zhong CHEN1),Jiayi, 1996) Abstract In this study the three dimensional mesoscale model, which is based on the Peking University Mesoscale Model, was used to simulate the wind field in the HEIFE experimental region. Simulations

  18. Mesoscale Simulations of Power Compaction

    SciTech Connect (OSTI)

    Lomov, I; Fujino, D; Antoun, T; Liu, B

    2009-08-06

    Mesoscale 3D simulations of metal and ceramic powder compaction in shock waves have been performed with an Eulerian hydrocode GEODYN. The approach was validated by simulating shock compaction of porous well-characterized ductile metal using Steinberg material model. Results of the simulations with handbook values for parameters of solid 2024 aluminum have good agreement with experimental compaction curves and wave profiles. Brittle ceramic materials are not so well studied as metals, so material model for ceramic (tungsten carbide) has been fitted to shock compression experiments of non-porous samples and further calibrated to match experimental compaction curves. Direct simulations of gas gun experiments with ceramic powder have been performed and showed good agreement with experimental data. Numerical shock wave profile has same character and thickness as measured with VISAR. Numerical results show reshock states above the single-shock Hugoniot line also observed in experiments. They found that to receive good quantitative agreement with experiment it is essential to perform 3D simulations.

  19. Soft X-ray techniques to study mesoscale magnetism

    E-Print Network [OSTI]

    Kortright, Jeffrey B.

    2003-01-01

    X-Ray Techniques to Study Mesoscale Magnetism Jeffrey B.X-Ray Techniques to Study Mesoscale Magnetism Jeffrey B.

  20. Modeled atmospheric radon concentrations from uranium mines

    SciTech Connect (OSTI)

    Droppo, J.G.

    1985-04-01

    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.

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

    E-Print Network [OSTI]

    Wang, Shuguang

    2006-04-12

    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...

  2. THE LOS ALAMOS NATIONAL LABORATORY ATMOSPHERIC TRANSPORT AND DIFFUSION MODELS

    SciTech Connect (OSTI)

    M. WILLIAMS

    1999-08-01

    The LANL atmospheric transport and diffusion models are composed of two state-of-the-art computer codes. The first is an atmospheric wind model called HOThlAC, Higher Order Turbulence Model for Atmospheric circulations. HOTMAC generates wind and turbulence fields by solving a set of atmospheric dynamic equations. The second is an atmospheric diffusion model called RAPTAD, Random Particle Transport And Diffusion. RAPTAD uses the wind and turbulence output from HOTMAC to compute particle trajectories and concentration at any location downwind from a source. Both of these models, originally developed as research codes on supercomputers, have been modified to run on microcomputers. Because the capability of microcomputers is advancing so rapidly, the expectation is that they will eventually become as good as today's supercomputers. Now both models are run on desktop or deskside computers, such as an IBM PC/AT with an Opus Pm 350-32 bit coprocessor board and a SUN workstation. Codes have also been modified so that high level graphics, NCAR Graphics, of the output from both models are displayed on the desktop computer monitors and plotted on a laser printer. Two programs, HOTPLT and RAPLOT, produce wind vector plots of the output from HOTMAC and particle trajectory plots of the output from RAPTAD, respectively. A third CONPLT provides concentration contour plots. Section II describes step-by-step operational procedures, specifically for a SUN-4 desk side computer, on how to run main programs HOTMAC and RAPTAD, and graphics programs to display the results. Governing equations, boundary conditions and initial values of HOTMAC and RAPTAD are discussed in Section III. Finite-difference representations of the governing equations, numerical solution procedures, and a grid system are given in Section IV.

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

    E-Print Network [OSTI]

    Meng, Zhiyong

    2007-09-17

    This dissertation examines the performance of an ensemble Kalman filter (EnKF) implemented in a mesoscale model in increasingly realistic contexts from under a perfect model assumption and in the presence of significant model error with synthetic...

  4. Journal of the Meteorological Society of Japan, Vol. 82, No. 5, pp. 1389--1397, 2004 1389 Mesoscale Assimilation of TMI Rainfall Data with 4DVAR

    E-Print Network [OSTI]

    Pu, Zhaoxia

    Journal of the Meteorological Society of Japan, Vol. 82, No. 5, pp. 1389--1397, 2004 1389 Mesoscale rainfall data into a mesoscale model, using a four-dimensional variational data assimilation (4DVAR on mesoscale forecasts (e.g., Supertyphoon Paka in 1997 (Pu et al. 2002)), as the global analysis provide

  5. Mesoscale Predictability of an Extreme Warm-Season Precipitation Event FUQING ZHANG, ANDREW M. ODINS, AND JOHN W. NIELSEN-GAMMON

    E-Print Network [OSTI]

    Mesoscale Predictability of an Extreme Warm-Season Precipitation Event FUQING ZHANG, ANDREW M Station, Texas (Manuscript received 22 November 2004, in final form 28 August 2005) ABSTRACT A mesoscale model is used to investigate the mesoscale predictability of an extreme precipitation event over central

  6. Graduate Opportunities in Atmospheric Modeling to Understand Greenhouse Gas Emissions

    E-Print Network [OSTI]

    Lin, John Chun-Han

    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

  7. Adjoint modeling for atmospheric pollution process sensitivity at regional scale

    E-Print Network [OSTI]

    Menut, Laurent

    , a strong pollution event was documented over Paris as part of the Etude et Simulation de la Qualite´ de l'airAdjoint modeling for atmospheric pollution process sensitivity at regional scale Laurent Menut 1998 the pollution event changes from a well-marked ozone plume issued from Paris to a more general

  8. From Multi-Sensor Tracking of Sea Surface Films to Mesoscale and Sub-Mesoscale Sea Surface Current Fields

    E-Print Network [OSTI]

    Hamburg,.Universität

    From Multi-Sensor Tracking of Sea Surface Films to Mesoscale and Sub-Mesoscale Sea Surface Current, Bundesstr. 53, 20146 Hamburg, Germany ABSTRACT The knowledge about mesoscale and sub-mesoscale sea surface to investigate mesoscale and sub-mesoscale turbulent features like eddies, particularly in coastal waters

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

    E-Print Network [OSTI]

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

    2013-01-01

    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...

  10. Experiences with the Application of the Non-Hydrostatic Mesoscale Model GESIMA for assessing Wind Potential in

    E-Print Network [OSTI]

    Heinemann, Detlev

    .physik.uni-oldenburg.de/ehf *GKSS Research Center Geesthacht, Max-Planck-Straße 1, D-21494 Geesthacht, Germany To asses wind are lim- ited. Especially the accuracy of predictions with these models for wind energy applications Introduction After an enormous growth of wind energy use in Ger- manys coastal regions the inland becomes more

  11. Implementation of the Immersed Boundary Method in the Weather Research and Forecasting model

    SciTech Connect (OSTI)

    Lundquist, K A

    2006-12-07

    Accurate simulations of atmospheric boundary layer flow are vital for predicting dispersion of contaminant releases, particularly in densely populated urban regions where first responders must react within minutes and the consequences of forecast errors are potentially disastrous. Current mesoscale models do not account for urban effects, and conversely urban scale models do not account for mesoscale weather features or atmospheric physics. The ultimate goal of this research is to develop and implement an immersed boundary method (IBM) along with a surface roughness parameterization into the mesoscale Weather Research and Forecasting (WRF) model. IBM will be used in WRF to represent the complex boundary conditions imposed by urban landscapes, while still including forcing from regional weather patterns and atmospheric physics. This document details preliminary results of this research, including the details of three distinct implementations of the immersed boundary method. Results for the three methods are presented for the case of a rotation influenced neutral atmospheric boundary layer over flat terrain.

  12. Acoustic Characterization of Mesoscale Objects

    SciTech Connect (OSTI)

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

    2007-03-13

    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.

  13. Mesoscale Metallic Pyramids with Nanoscale Tips

    E-Print Network [OSTI]

    Odom, Teri W.

    Mesoscale Metallic Pyramids with Nanoscale Tips Joel Henzie, Eun-Soo Kwak, and Teri W. Odom generate free-standing mesoscale metallic pyramids composed of one or more materials and having nanoscale tips (radii of curvature of less than 2 nm). Mesoscale holes (100-300 nm) in a chromium film are used

  14. Engineering mesoscale structures with distinct dynamical implications

    E-Print Network [OSTI]

    Engineering mesoscale structures with distinct dynamical implications Anne-Ly Do1 , Johannes H that there are certain mesoscale subgraphs that have precise and distinct consequences for the system-level dynamics. In particular, if mesoscale symmetries are present then eigenvectors of the Jacobian localise on the symmetric

  15. space/time and modeling formalisms; extensions: Multilevel modeling in CA

    E-Print Network [OSTI]

    Utrecht, Universiteit

    expectation (attractors, mesoscale patterns) · Exploration what happens if we assume.... emergent behaviour MESOSCALE ENTITIES: - discovery and description - modeling these entities -'beyond' dynamical systems (IBM models) PREDEFINED MULTIPLE LEVEL - e.g. predefined cells as mesoscale - multiple timescales

  16. Review of structure representation and reconstruction on mesoscale and microscale

    SciTech Connect (OSTI)

    Li, Dongsheng

    2014-05-01

    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.

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

    E-Print Network [OSTI]

    Reichler, Thomas

    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 as the atmospheric component of a coupled modeling system. The present version of the coupled system, the MPI Earth

  18. Ph.D. DISSERTATION MODELING PLANT-SOIL-ATMOSPHERE CARBON DIOXIDE EXCHANGE

    E-Print Network [OSTI]

    Tu, Kevin

    Ph.D. DISSERTATION MODELING PLANT-SOIL-ATMOSPHERE CARBON DIOXIDE EXCHANGE USING OPTIMALITY...............................................................................................1 I. A REVIEW OF REMOTE SENSING MODELS........................................................7...............................................................7 Remote Sensing Models

  19. A multiple-scale simulation of variations in atmospheric carbon dioxide using a coupled biosphere-atmospheric model

    E-Print Network [OSTI]

    Collett Jr., Jeffrey L.

    A multiple-scale simulation of variations in atmospheric carbon dioxide using a coupled biosphere, carbon dioxide, biosphere, regional-scale modeling, missing sink, carbon dioxide fluxes Citation), A multiple-scale simulation of variations in atmospheric carbon dioxide using a coupled biosphere

  20. The role of environmental factors that influence atmospheric propagation of sound originating from freeway noise sources is studied with a combination of field experiments and numerical simulations. Acoustic

    E-Print Network [OSTI]

    for mesoscale applications. This method was implemented and evaluated within the environmental modeling

  1. Thermal shallow water models of geostrophic turbulence in Jovian atmospheres

    SciTech Connect (OSTI)

    Warneford, Emma S. Dellar, Paul J.

    2014-01-15

    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.

  2. Regional forecasting with global atmospheric models; Third year report

    SciTech Connect (OSTI)

    Crowley, T.J.; North, G.R.; Smith, N.R.

    1994-05-01

    This report was prepared by the Applied Research Corporation (ARC), College Station, Texas, under subcontract to Pacific Northwest Laboratory (PNL) as part of a global climate studies task. The task supports site characterization work required for the selection of a potential high-level nuclear waste repository and is part of the Performance Assessment Scientific Support (PASS) Program at PNL. The work is under the overall direction of the Office of Civilian Radioactive Waste Management (OCRWM), US Department of Energy Headquarters, Washington, DC. The scope of the report is to present the results of the third year`s work on the atmospheric modeling part of the global climate studies task. The development testing of computer models and initial results are discussed. The appendices contain several studies that provide supporting information and guidance to the modeling work and further details on computer model development. Complete documentation of the models, including user information, will be prepared under separate reports and manuals.

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

    E-Print Network [OSTI]

    Lin, John Chun-Han

    is essential for atmospheric transport and chemistry models. Eule- rian treatments are generally plagued- proving atmospheric transport and chemistry models (Rood 1987; Wang and Hutter 2001). The growing interestToward a Fully Lagrangian Atmospheric Modeling System JAHRUL M. ALAM AND JOHN C. LIN Department

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

    E-Print Network [OSTI]

    Hoofard, Michael Eugene

    1986-01-01

    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... fulfillment of the requirements for the degree of MASTER OF SCIENCE August 1986 Major Subj ect: Meteorology MESOSCALE CONVECTIVE COMPLEX VS. NON-MESOSCALE CONVECTIVE COMPLEX THUNDERSTORMS: A COMPARISON OF SELECTED METEOROLOGICAL VARIABLES A Thesis...

  5. Computing Limb Darkening Coefficients from Stellar Atmosphere Models

    E-Print Network [OSTI]

    David Heyrovsky

    2006-10-24

    We explore the sensitivity of limb darkening coefficients computed from stellar atmosphere models to different least-squares fitting methods. We demonstrate that conventional methods are strongly biased to fitting the stellar limb. Our suggested method of fitting by minimizing the radially integrated squared residual yields improved fits with better flux conservation. The differences of the obtained coefficients from commonly used values are observationally significant. We show that the new values are in better agreement with solar limb darkening measurements as well as with coefficients reported from analyses of eclipsing binary light curves.

  6. Fingering convection and cloudless models for cool brown dwarf atmospheres

    E-Print Network [OSTI]

    Tremblin, P; Mourier, P; Baraffe, I; Chabrier, G; Drummond, B; Homeier, D; Venot, O

    2015-01-01

    This work aims to improve the current understanding of the atmospheres of brown dwarfs, especially cold ones with spectral type T and Y, whose modeling is a current challenge. Silicate and iron clouds are believed to disappear at the photosphere at the L/T transition, but cloudless models fail to reproduce correctly the spectra of T dwarfs, advocating for the addition of more physics, e.g. other types of clouds or internal energy transport mechanisms. We use a one-dimensional (1D) radiative/convective equilibrium code ATMO to investigate this issue. This code includes both equilibrium and out-of-equilibrium chemistry and solves consistently the PT structure. Included opacity sources are H2-H2, H2-He, H2O, CO, CO2, CH4, NH3, K, Na, and TiO, VO if they are present in the atmosphere. We show that the spectra of Y dwarfs can be accurately reproduced with a cloudless model if vertical mixing and NH3 quenching are taken into account. T dwarf spectra still have some reddening in e.g. J - H compared to cloudless mode...

  7. Atmospheric Dispersion Modeling: Challenges of the Fukushima Daiichi Response

    SciTech Connect (OSTI)

    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

    2012-05-01

    The U.S. Department of Energy’s (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 NARAC’s 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.

  8. MESOSCALE THEORY OF GRAINS AND CELLS: POLYCRYSTALS & PLASTICITY

    E-Print Network [OSTI]

    Sethna, James P.

    MESOSCALE THEORY OF GRAINS AND CELLS: POLYCRYSTALS & PLASTICITY A Dissertation Presented RIGHTS RESERVED #12;MESOSCALE THEORY OF GRAINS AND CELLS: POLYCRYSTALS & PLASTICITY Surachate Limkumnerd, continuum explanation for the evolution of dislocations into sharp walls. We present here a mesoscale theory

  9. Dynamic Filtering and Mining Triggers in Mesoscale Meteorology Forecasting

    E-Print Network [OSTI]

    Plale, Beth

    Dynamic Filtering and Mining Triggers in Mesoscale Meteorology Forecasting Nithya N. Vijayakumar {rramachandran, xli}@itsc.uah.edu Abstract-- Mesoscale meteorology forecasting as a data driven application Triggers, Data Mining, Stream Processing, Meteorology Forecasting I. INTRODUCTION Mesoscale meteorologists

  10. Optically Directed Assembly of Continuous Mesoscale Filaments...

    Office of Scientific and Technical Information (OSTI)

    Optically Directed Assembly of Continuous Mesoscale Filaments Bahns, J. T.; Sankaranarayanan, S. K. R. S.; Gray, S. K.; Chen, L. Not Available American Physical Society None USDOE...

  11. A discrete forward-modeling method for characterizing occultation lightcurves of tenuous planetary atmospheres

    E-Print Network [OSTI]

    Siu, Ho Chit

    2015-01-01

    We present a discrete numerical approach for forward-modeling lightcurves from stellar occultations by planetary atmospheres. Our discrete approach provides a way to arbitrarily set atmospheric properties at any radius ...

  12. Model formalisms, continued; CA, ODE, Boolean networks

    E-Print Network [OSTI]

    Utrecht, Universiteit

    ­ Mesoscale patterns ­ Zoo QUESTIONS? TODAY · CA as modeling tool: common generalisations · alternative

  13. Ecospace: Prediction of Mesoscale Spatial Patterns in Trophic

    E-Print Network [OSTI]

    Pauly, Daniel

    Ecospace: Prediction of Mesoscale Spatial Patterns in Trophic Relationships of Exploited Ecosystems Springer-Verlag 539 Walters, C., D. Pauly and V. Christensen. 1999. Ecospace: Prediction of mesoscale

  14. Mesoscale Simulations of Particulate Flows with Parallel Distributed...

    Office of Scientific and Technical Information (OSTI)

    Mesoscale Simulations of Particulate Flows with Parallel Distributed Lagrange Multiplier Technique Citation Details In-Document Search Title: Mesoscale Simulations of Particulate...

  15. Mesoscale simulations of particulate flows with parallel distributed...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Mesoscale simulations of particulate flows with parallel distributed Lagrange multiplier technique Citation Details In-Document Search Title: Mesoscale simulations...

  16. P h y s i c a l O c e a n o g r a p h y D i v i s i o n Role of Mesoscale Eddies on Decadal Variability of the South

    E-Print Network [OSTI]

    P h y s i c a l O c e a n o g r a p h y D i v i s i o n Role of Mesoscale Eddies on Decadal representation of mesoscale eddies in the ocean. Therefore, the impact of mesoscale eddies on climate variability the mesoscale eddies are properly parameterized in CMIP5 models. Our overall goal is to explore the impact

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

    E-Print Network [OSTI]

    Knievel, Jason Clark

    Temporal Changes in Wind as Objects for Evaluating Mesoscale Numerical Weather Prediction DARAN L changes in simulated and observed 10-m (AGL) winds. The method is demon- strated on a 1-yr collection of 1-day simulations by the fifth-generation Pennsylvania State University­ National Center for Atmospheric

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

    SciTech Connect (OSTI)

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

    2012-04-11

    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.

  19. Mesoscale Elucidation of Biofilm Shear Behavior

    E-Print Network [OSTI]

    Barai, Pallab; Mukherjee, Partha P

    2015-01-01

    Formation of bacterial colonies as biofilm on the surface/interface of various objects has the potential to impact not only human health and disease but also energy and environmental considerations. Biofilms can be regarded as soft materials, and comprehension of their shear response to external forces is a key element to the fundamental understanding. A mesoscale model has been presented in this article based on digitization of a biofilm microstructure. Its response under externally applied shear load is analyzed. Strain stiffening type behavior is readily observed under high strain loads due to the unfolding of chains within soft polymeric substrate. Sustained shear loading of the biofilm network results in strain localization along the diagonal direction. Rupture of the soft polymeric matrix can potentially reduce the intercellular interaction between the bacterial cells. Evolution of stiffness within the biofilm network under shear reveals two regions: a) initial increase in stiffness due to strain stiffe...

  20. Mesoscale Characterization of Coupled Hydromechanical Behavior of a Fractured Porous Slope in Response to Free Water-Surface Movement

    E-Print Network [OSTI]

    Guglielmi, Y.

    2008-01-01

    Mesoscale Characterization of Coupled Hydromechanicalinstrumented for mesoscale hydraulic and mechanicalwords: Fracture; Rock slope; Mesoscale; In situ poroelastic

  1. An adaptive reduction algorithm for efficient chemical calculations in global atmospheric chemistry models

    E-Print Network [OSTI]

    Santillana, Mauricio

    An adaptive reduction algorithm for efficient chemical calculations in global atmospheric chemistry: Atmospheric chemistry Multi-scale analysis Time-scale separation Reduction of chemical kinetics a b s t r a c of the concentrations of chemical species in global 3-D models of atmospheric chemistry. Our strategy consists

  2. Mesoscale flows in large aspect ratio simulations of turbulent compressible convection

    E-Print Network [OSTI]

    F. Rincon; F. Lignieres; M. Rieutord

    2006-11-28

    We present the results of a very large aspect ratio (42.6) numerical simulation of fully compressible turbulent convection in a polytropic atmosphere, and focus on the properties of large-scale flows. Mesoscale patterns dominate the turbulent energy spectrum. We show that these structures, which had already been observed in Boussinesq simulations by Cattaneo et al. (2001), have a genuine convective origin and do not result directly from collective interactions of the smaller scales of the flow, even though their growth is strongly affected by nonlinear transfers. If this result is relevant to the solar photosphere, it suggests that the dominant convective mode below the Sun's surface may be at mesoscales.

  3. Molecule-Mimetic Chemistry and Mesoscale Self-Assembly

    E-Print Network [OSTI]

    Prentiss, Mara

    Molecule-Mimetic Chemistry and Mesoscale Self-Assembly NED B. BOWDEN, MARCUS WECK, INSUNG S. CHOI, and possible uses for these processes and assemblies.6-22 Mesoscale Self-Assembly (MESA) Mesoscale Self technically, and especially in physics, a mesoscale object is one whose dimensions are comparable to the scale

  4. 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

  5. Models of neutron star atmospheres enriched with nuclear burning ashes

    E-Print Network [OSTI]

    Nättilä, Joonas; Kajava, Jari J E; Poutanen, Juri

    2015-01-01

    Low-mass X-ray binaries hosting neutron stars (NS) exhibit thermonuclear (type-I) X-ray bursts, which are powered by unstable nuclear burning of helium and/or hydrogen into heavier elements deep in the NS "ocean". In some cases the burning ashes may rise from the burning depths up to the NS photosphere by convection, leading to the appearance of the metal absorption edges in the spectra, which then force the emergent X-ray burst spectra to shift toward lower energies. These effects may have a substantial impact on the color correction factor $f_c$ and the dilution factor $w$, the parameters of the diluted blackbody model $F_E \\approx w B_E(f_c T_{eff})$ that is commonly used to describe the emergent spectra from NSs. The aim of this paper is to quantify how much the metal enrichment can change these factors. We have developed a new NS atmosphere modeling code, which has a few important improvements compared to our previous code required by inclusion of the metals. The opacities and the internal partition func...

  6. Mapping mesoscale heterogeneity in the plastic deformation of a copper single crystal

    E-Print Network [OSTI]

    Magid, K. R.

    2009-01-01

    619. page 18 Mapping mesoscale heterogeneity in a deformedthese planes. page 36 Mapping mesoscale heterogeneity in aJanuary 2009, 77–107 Mapping mesoscale heterogeneity in the

  7. Effect of ocean mesoscale variability on the mean state of tropical Atlantic climate

    E-Print Network [OSTI]

    Seo, H; Jochum, M; Murtugudde, R; Miller, A J

    2006-01-01

    Effect of Ocean Mesoscale Variability on the Mean State ofthe effect of oceanic mesoscale features on the mean climatemodel, resolving oceanic mesoscale variability leads to a

  8. Linking atomistic and mesoscale simulations of nanocrystalline materials : quantitative validation for the case of grain growth.

    SciTech Connect (OSTI)

    Moldovan, D.; Wolf, D.; Phillpot, S. R.; Materials Science Division; Louisiana State Univ.

    2003-11-01

    Using grain growth in nanocrystalline palladium as a simple case study, we demonstrate how a novel mesoscale approach for simulating microstructural evolution in polycrystalline materials can be validated directly against atomic-level simulations of the same system. We first describe molecular dynamics simulations of grain growth in a columnar model microstructure. The atomic-level insights into the grain-growth mechanism gained from these simulations, particularly in the role of grain rotations, are captured theoretically for incorporation into the mesoscale approach, in which the objects evolving in space and time are the grain boundaries and grain junctions rather than the atoms. With all the input parameters to the mesoscale being physically well defined and obtained directly from the atomic-level simulations, the mesoscale simulations are fully prescribed. We find that the morphology of the mesoscale system evolves in an almost identical manner with that of the molecular dynamics simulation, demonstrating that the length- and time-scale linking has been performed correctly. When applied to systems containing large numbers of grains, the now validated mesoscale simulation approach allows the growth topology and long-time growth kinetics to be determined. As an outlook, we describe how the effects of applied stress can be incorporated.

  9. Energy considerations in the Community Atmosphere Model (CAM)

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Williamson, David L.; Olson, Jerry G.; Hannay, Cécile; Toniazzo, Thomas; Yudin, Valery; Taylor, Mark

    2015-06-30

    An error in the energy formulation in the Community Atmosphere Model (CAM) is identified and corrected. Ten year AMIP simulations are compared using the correct and incorrect energy formulations. Statistics of selected primary variables all indicate physically insignificant differences between the simulations, comparable to differences with simulations initialized with rounding sized perturbations. The two simulations are so similar mainly because of an inconsistency in the application of the incorrect energy formulation in the original CAM. CAM used the erroneous energy form to determine the states passed between the parameterizations, but used a form related to the correct formulation for themore »state passed from the parameterizations to the dynamical core. If the incorrect form is also used to determine the state passed to the dynamical core the simulations are significantly different. In addition, CAM uses the incorrect form for the global energy fixer, but that seems to be less important. The difference of the magnitude of the fixers using the correct and incorrect energy definitions is very small.« less

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

    E-Print Network [OSTI]

    Jablonowski, Christiane

    Three Dimensional Adaptive Mesh Refinement on a Spherical Shell for Atmospheric Models for Atmospheric Research 1. Introduction One of the most important advances needed in global climate models of this project is a parallel adaptive grid library, which is currently under development at the University

  11. The Tropospheric Jet Response to Prescribed Zonal Forcing in an Idealized Atmospheric Model

    E-Print Network [OSTI]

    Chen, Gang

    The Tropospheric Jet Response to Prescribed Zonal Forcing in an Idealized Atmospheric Model GANG 2007, in final form 19 November 2007) ABSTRACT This paper explores the tropospheric jet shift to a prescribed zonal torque in an idealized dry atmospheric model with high stratospheric resolution. The jet

  12. Postulated Mesoscale Quantum of Internal Friction Hysteresis

    E-Print Network [OSTI]

    Randall D. Peters

    2004-05-27

    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.

  13. On the Cool Side: Modeling the Atmospheres of Brown Dwarfs and Giant Planets

    E-Print Network [OSTI]

    Marley, Mark S

    2014-01-01

    The atmosphere of a brown dwarf or extrasolar giant planet controls the spectrum of radiation emitted by the object and regulates its cooling over time. While the study of these atmospheres has been informed by decades of experience modeling stellar and planetary atmospheres, the distinctive characteristics of these objects present unique challenges to forward modeling. In particular, complex chemistry arising from molecule-rich atmospheres, molecular opacity line lists (sometimes running to 10 billion absorption lines or more) multiple cloud-forming condensates, and disequilibrium chemical processes all combine to create a challenging task for any modeling effort. This review describes the process of incorporating these complexities into one-dimensional radiative-convective equilibrium models of sub-stellar objects. We discuss the underlying mathematics as well as the techniques used to model the physics, chemistry, radiative transfer, and other processes relevant to understanding these atmospheres. The revi...

  14. A scalable high-order discontinuous Galerkin method for global atmospheric modeling Hae-Won Choia

    E-Print Network [OSTI]

    Nair, Ramachandran D.

    system model will require a highly scalable and accurate flux-form formulation of atmospheric dynamics supercomputers. 1. INTRODUCTION The future evolution of the Community Climate System Model (CCSM) into an Earth

  15. PHOTOCHEMISTRY IN TERRESTRIAL EXOPLANET ATMOSPHERES. I. PHOTOCHEMISTRY MODEL AND BENCHMARK CASES

    E-Print Network [OSTI]

    Hu, Renyu

    We present a comprehensive photochemistry model for exploration of the chemical composition of terrestrial exoplanet atmospheres. The photochemistry model is designed from the ground up to have the capacity to treat all ...

  16. Preindustrial to present-day changes in tropospheric hydroxyl radical and methane lifetime from the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP)

    E-Print Network [OSTI]

    2013-01-01

    hindcasts of atmospheric chemistry: the role of meteorology,J. : Introduction to atmospheric chemistry, Princeton Uni-and Zeng, G. : The Atmospheric Chemistry and Climate Model

  17. Laboratory measurements and modeling of trace atmospheric species

    E-Print Network [OSTI]

    Sheehy, Philip M. (Philip Michael)

    2005-01-01

    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, ...

  18. Meso-scale turbulence in living fluids

    E-Print Network [OSTI]

    Henricus H. Wensink; Jörn Dunkel; Sebastian Heidenreich; Knut Drescher; Raymond E. Goldstein; Hartmut Löwen; Julia M. Yeomans

    2012-08-21

    Turbulence is ubiquitous, from oceanic currents to small-scale biological and quantum systems. Self-sustained turbulent motion in microbial suspensions presents an intriguing example of collective dynamical behavior amongst the simplest forms of life, and is important for fluid mixing and molecular transport on the microscale. The mathematical characterization of turbulence phenomena in active non-equilibrium fluids proves even more difficult than for conventional liquids or gases. It is not known which features of turbulent phases in living matter are universal or system-specific, or which generalizations of the Navier-Stokes equations are able to describe them adequately. Here, we combine experiments, particle simulations, and continuum theory to identify the statistical properties of self-sustained meso-scale turbulence in active systems. To study how dimensionality and boundary conditions affect collective bacterial dynamics, we measured energy spectra and structure functions in dense Bacillus subtilis suspensions in quasi-2D and 3D geometries. Our experimental results for the bacterial flow statistics agree well with predictions from a minimal model for self-propelled rods, suggesting that at high concentrations the collective motion of the bacteria is dominated by short-range interactions. To provide a basis for future theoretical studies, we propose a minimal continuum model for incompressible bacterial flow. A detailed numerical analysis of the 2D case shows that this theory can reproduce many of the experimentally observed features of self-sustained active turbulence.

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

    E-Print Network [OSTI]

    Wang, Chien.; Prinn, Ronald G.

    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. ...

  20. Measurement and Modeling of Shortwave Irradiance Components in Cloud-Free Atmospheres

    E-Print Network [OSTI]

    Measurement and Modeling of Shortwave Irradiance Components in Cloud-Free Atmospheres Rangasayi to classify the earth-atmospheric solar radiation into several components - direct solar surface irradiance (Edirect), diffuse-sky downward surface irradiance (Ediffuse), total surface irradiance, and upwelling flux

  1. High resolution transmission spectroscopy as a diagnostic for Jovian exoplanet atmospheres: constraints from theoretical models

    SciTech Connect (OSTI)

    Kempton, Eliza M.-R.; Perna, Rosalba; Heng, Kevin

    2014-11-01

    We present high resolution transmission spectra of giant planet atmospheres from a coupled three-dimensional (3D) atmospheric dynamics and transmission spectrum model that includes Doppler shifts which arise from winds and planetary motion. We model Jovian planets covering more than two orders of magnitude in incident flux, corresponding to planets with 0.9-55 day orbital periods around solar-type stars. The results of our 3D dynamical models reveal certain aspects of high resolution transmission spectra that are not present in simple one-dimensional (1D) models. We find that the hottest planets experience strong substellar to anti-stellar (SSAS) winds, resulting in transmission spectra with net blueshifts of up to 3 km s{sup –1}, whereas less irradiated planets show almost no net Doppler shifts. We find only minor differences between transmission spectra for atmospheres with temperature inversions and those without. Compared to 1D models, peak line strengths are significantly reduced for the hottest atmospheres owing to Doppler broadening from a combination of rotation (which is faster for close-in planets under the assumption of tidal locking) and atmospheric winds. Finally, high resolution transmission spectra may be useful in studying the atmospheres of exoplanets with optically thick clouds since line cores for very strong transitions should remain optically thick to very high altitude. High resolution transmission spectra are an excellent observational test for the validity of 3D atmospheric dynamics models, because they provide a direct probe of wind structures and heat circulation. Ground-based exoplanet spectroscopy is currently on the verge of being able to verify some of our modeling predictions, most notably the dependence of SSAS winds on insolation. We caution that interpretation of high resolution transmission spectra based on 1D atmospheric models may be inadequate, as 3D atmospheric motions can produce a noticeable effect on the absorption signatures.

  2. ATMOSPHERIC TURBULENCE MODELING AND IMPLICATIONS FOR WIND ENERGY

    E-Print Network [OSTI]

    Chow, Fotini Katopodes

    @berkeley.edu Abstract The near-surface structure of atmospheric turbu- lence affects the design and operation of wind may pro- vide untapped resources for wind power extraction. This study uses large-eddy simulation (LES- ameters of 80-120 m. Current operational practices for wind farm operation and siting rely on power law

  3. Lesson Summary Students will use models of Earth's atmosphere

    E-Print Network [OSTI]

    Mojzsis, Stephen J.

    to Do Scientific Inquiry Physical Science Transfer of Energy Earth and Space Science Structure the greenhouse from the captured solar energy. Certain gases in Earth's atmosphere ­ especially water vapor by storing and releasing energy from the sun. Materials: Large pickle jars, smaller jelly jar, laboratory

  4. 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]

    Daniels, Megan Hanako

    2010-01-01

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

  5. Glider Path-Planning for Optimal Sampling of Mesoscale Eddies

    E-Print Network [OSTI]

    Smith, Ryan N.

    Glider Path-Planning for Optimal Sampling of Mesoscale Eddies Daniel Hernandez1 , Ryan Smith2 these, mesoscale eddies are of particular interest due to the relevance they have in many oceano

  6. On the Forecasting of Orogenic Mesoscale Convective Complexes

    E-Print Network [OSTI]

    Tucker, Donna F.; Zentmire, Kristine S.

    1999-12-01

    ., 1980: Mesoscale convective complexes. Bull. Amer. Meteor. Soc., 61, 1374–1387. , 1983: Large-scale meteorological conditions associated with midlatitude mesoscale convective complexes. Mon. Wea. Rev., 111, 1475–1493. , D. M. Rodgers, and K. W. Howard..., 1982: Mesoscale convective complexes over the United States during 1981—Annual sum- mary. Mon. Wea. Rev., 110, 1501–1514. , K. W. Howard, D. L. Bartels, and D. M. Rodgers, 1986: Me- soscale convective complexes in the middle latitudes. Mesoscale...

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

    E-Print Network [OSTI]

    Covey, Curt

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

  8. Accelerated Iterative Method for Solving Steady Solutions of Linearized Atmospheric Models

    E-Print Network [OSTI]

    Watanabe, Masahiro

    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

  9. HIGH-ORDER FINITE VOLUME SCHEMES FOR LAYERED ATMOSPHERIC MODELS

    E-Print Network [OSTI]

    of use of layered models are: air pollution models (see for example the early study in [1]), moisture

  10. A Coupling Methodology for Mesoscale-informed Nuclear Fuel Performance Codes

    SciTech Connect (OSTI)

    Michael Tonks; Derek Gaston; Cody Permann; Paul Millett; Glen Hansen; Dieter Wolf

    2010-10-01

    This study proposes an approach for capturing the effect of microstructural evolution on reactor fuel performance by coupling a mesoscale irradiated microstructure model with a finite element fuel performance code. To achieve this, the macroscale system is solved in a parallel, fully coupled, fully-implicit manner using the preconditioned Jacobian-free Newton Krylov (JFNK) method. Within the JFNK solution algorithm, microstructure-influenced material parameters are calculated by the mesoscale model and passed back to the macroscale calculation. Due to the stochastic nature of the mesoscale model, a dynamic fitting technique is implemented to smooth roughness in the calculated material parameters. The proposed methodology is demonstrated on a simple model of a reactor fuel pellet. In the model, INL’s BISON fuel performance code calculates the steady-state temperature profile in a fuel pellet and the microstructure-influenced thermal conductivity is determined with a phase field model of irradiated microstructures. This simple multiscale model demonstrates good nonlinear convergence and near ideal parallel scalability. By capturing the formation of large mesoscale voids in the pellet interior, the multiscale model predicted the irradiation-induced reduction in the thermal conductivity commonly observed in reactors.

  11. Mesoscale morphologies in polymer thin films.

    SciTech Connect (OSTI)

    Ramanathan, M.; Darling, S. B. (Center for Nanoscale Materials)

    2011-06-01

    In the midst of an exciting era of polymer nanoscience, where the development of materials and understanding of properties at the nanoscale remain a major R&D endeavor, there are several exciting phenomena that have been reported at the mesoscale (approximately an order of magnitude larger than the nanoscale). In this review article, we focus on mesoscale morphologies in polymer thin films from the viewpoint of origination of structure formation, structure development and the interaction forces that govern these morphologies. Mesoscale morphologies, including dendrites, holes, spherulites, fractals and honeycomb structures have been observed in thin films of homopolymer, copolymer, blends and composites. Following a largely phenomenological level of description, we review the kinetic and thermodynamic aspects of mesostructure formation outlining some of the key mechanisms at play. We also discuss various strategies to direct, limit, or inhibit the appearance of mesostructures in polymer thin films as well as an outlook toward potential areas of growth in this field of research.

  12. Mesoscale analysis of segmental dynamics in microphase-segregated polyurea

    E-Print Network [OSTI]

    Grujicic, Mica

    Mesoscale analysis of segmental dynamics in microphase- segregated polyurea M. Grujicic · B-atom molecular dynamics techniques. To overcome this problem, mesoscale coarse-grain simulation methods of constituent atom-size particles. Within the mesoscale methods, on the other hand, this atomistic description

  13. Computational upscaling of inertia effects from porescale to mesoscale

    E-Print Network [OSTI]

    Peszynska, Malgorzata

    Computational upscaling of inertia effects from porescale to mesoscale Malgorzata Peszy´nska1 for computational upscaling of flow from porescale (microscale) to lab scale (mesoscale). In particular, we solve laboratory for porous me- dia which delivers data needed for mesoscale simulations by performing microscale

  14. MPO 663 -Convective and Mesoscale Meteorology Brian Mapes, Spring 2008

    E-Print Network [OSTI]

    Miami, University of

    MPO 663 - Convective and Mesoscale Meteorology Brian Mapes, Spring 2008 I intend for students and mesoscale phenomena. 2. Working understanding of several of these tools, cultivated via homework, including. A sense of how convective and mesoscale phenomena fit into larger scales, gained via short current

  15. GLOBAL PATTERN OF MESOSCALE VARIABILITY IN SEA SURFACE HEIGHT

    E-Print Network [OSTI]

    Kaplan, Alexey

    GLOBAL PATTERN OF MESOSCALE VARIABILITY IN SEA SURFACE HEIGHT AND ITS DYNAMICAL CAUSES Alexey separate the mesoscale variability of sea surface heights into its spatial and temporal components of mesoscale variability in different areas to dynamical causes. Major portion of it can be explained

  16. A system of launchable mesoscale robots for distributed sensing

    E-Print Network [OSTI]

    Voyles, Richard

    A system of launchable mesoscale robots for distributed sensing Kemal B. Yesina , Bradley J technologies to develop active vision modules for the mesoscale robot. A single chip CMOS video sensor is used- log video signals from the camera. Keywords: launchable, mobile, mesoscale, camera, pan-tilt 1

  17. MESOSCALE EDDIES Peter B. Rhines, University of Washington,

    E-Print Network [OSTI]

    MESOSCALE EDDIES Peter B. Rhines, University of Washington, School of Oceanography, Box 357940, Seattle, WA 98195 7940, USA Copyright ^ 2001 Academic Press doi:10.1006/rwos.2001.0143 Mesoscale eddies that strongly feel viscosity, to `mesoscale eddies' that strongly feel the Earth's rota- tion, to great `gyres

  18. Accessing biology's toolbox for the mesoscale biofabrication of soft matter

    E-Print Network [OSTI]

    Raghavan, Srinivasa

    Accessing biology's toolbox for the mesoscale biofabrication of soft matter Gregory F. Payne,bf James N. Culverag and William E. Bentley*ab Biology is a master of mesoscale science, possessing will provide a biocompatible approach to mesoscale science and yield products that are safe, sustainable

  19. HYBRID DECADE-MEAN GLOBAL SEA LEVEL WITH MESOSCALE RESOLUTION

    E-Print Network [OSTI]

    HYBRID DECADE-MEAN GLOBAL SEA LEVEL WITH MESOSCALE RESOLUTION Nikolai A. Maximenko1 and Pearn P of twin-satellite mission GRACE and mesoscale sea level tilt derived from the momentum balance as seen 55 #12;sea level exhibits excellent accuracy on mesoscale, but may contain significant systematic

  20. Particle-Based Mesoscale Hydrodynamic Techniques

    E-Print Network [OSTI]

    Hiroshi Noguchi; Norio Kikuchi; Gerhard Gompper

    2006-10-31

    Dissipative particle dynamics (DPD) and multi-particle collision (MPC) dynamics are powerful tools to study mesoscale hydrodynamic phenomena accompanied by thermal fluctuations. To understand the advantages of these types of mesoscale simulation techniques in more detail, we propose new two methods, which are intermediate between DPD and MPC -- DPD with a multibody thermostat (DPD-MT), and MPC-Langevin dynamics (MPC-LD). The key features are applying a Langevin thermostat to the relative velocities of pairs of particles or multi-particle collisions, and whether or not to employ collision cells. The viscosity of MPC-LD is derived analytically, in very good agreement with the results of numerical simulations.

  1. A comparison of chemistry and dust cloud formation in ultracool dwarf model atmospheres

    E-Print Network [OSTI]

    Ch. Helling; A. Ackerman; F. Allard; M. Dehn; P. Hauschildt; D. Homeier; K. Lodders; M. Marley; F. Rietmeijer; T. Tsuji; P. Woitke

    2008-09-24

    The atmospheres of substellar objects contain clouds of oxides, iron, silicates, and other refractory condensates. Water clouds are expected in the coolest objects. The opacity of these `dust' clouds strongly affects both the atmospheric temperature-pressure profile and the emergent flux. Thus any attempt to model the spectra of these atmospheres must incorporate a cloud model. However the diversity of cloud models in atmospheric simulations is large and it is not always clear how the underlying physics of the various models compare. Likewise the observational consequences of different modeling approaches can be masked by other model differences, making objective comparisons challenging. In order to clarify the current state of the modeling approaches, this paper compares five different cloud models in two sets of tests. Test case 1 tests the dust cloud models for a prescribed L, L--T, and T-dwarf atmospheric (temperature T, pressure p, convective velocity vconv)-structures. Test case 2 compares complete model atmosphere results for given (effective temperature Teff, surface gravity log g). All models agree on the global cloud structure but differ in opacity-relevant details like grain size, amount of dust, dust and gas-phase composition. Comparisons of synthetic photometric fluxes translate into an modelling uncertainty in apparent magnitudes for our L-dwarf (T-dwarf) test case of 0.25 < \\Delta m < 0.875 (0.1 < \\Delta m M 1.375) taking into account the 2MASS, the UKIRT WFCAM, the Spitzer IRAC, and VLT VISIR filters with UKIRT WFCAM being the most challenging for the models. (abr.)

  2. NOAA's Office of Oceanic and Atmospheric Research Roundtable: Earth System Modeling

    E-Print Network [OSTI]

    Summary NOAA's Office of Oceanic and Atmospheric Research Roundtable: Earth System Modeling in Environmental Sciences at the University of Colorado, centered on Earth System Modeling and OAR's role develop and/or can use accurate and timely predictions of the Earth system that come from modeling. The 18

  3. Modeling the Exchanges of Energy, Water, and Carbon Between Continents and the Atmosphere

    E-Print Network [OSTI]

    Collett Jr., Jeffrey L.

    Modeling the Exchanges of Energy, Water, and Carbon Between Continents and the Atmosphere P. J circulation models used for climate simulation and weather fore- casting require the fluxes of radiation, heat incorporate bio- geochemical and ecological knowledge and, when coupled with advanced climate and ocean models

  4. PHOTOCHEMISTRY IN TERRESTRIAL EXOPLANET ATMOSPHERES. I. PHOTOCHEMISTRY MODEL AND BENCHMARK CASES

    SciTech Connect (OSTI)

    Hu Renyu; Seager, Sara; Bains, William

    2012-12-20

    We present a comprehensive photochemistry model for exploration of the chemical composition of terrestrial exoplanet atmospheres. The photochemistry model is designed from the ground up to have the capacity to treat all types of terrestrial planet atmospheres, ranging from oxidizing through reducing, which makes the code suitable for applications for the wide range of anticipated terrestrial exoplanet compositions. The one-dimensional chemical transport model treats up to 800 chemical reactions, photochemical processes, dry and wet deposition, surface emission, and thermal escape of O, H, C, N, and S bearing species, as well as formation and deposition of elemental sulfur and sulfuric acid aerosols. We validate the model by computing the atmospheric composition of current Earth and Mars and find agreement with observations of major trace gases in Earth's and Mars' atmospheres. We simulate several plausible atmospheric scenarios of terrestrial exoplanets and choose three benchmark cases for atmospheres from reducing to oxidizing. The most interesting finding is that atomic hydrogen is always a more abundant reactive radical than the hydroxyl radical in anoxic atmospheres. Whether atomic hydrogen is the most important removal path for a molecule of interest also depends on the relevant reaction rates. We also find that volcanic carbon compounds (i.e., CH{sub 4} and CO{sub 2}) are chemically long-lived and tend to be well mixed in both reducing and oxidizing atmospheres, and their dry deposition velocities to the surface control the atmospheric oxidation states. Furthermore, we revisit whether photochemically produced oxygen can cause false positives for detecting oxygenic photosynthesis, and find that in 1 bar CO{sub 2}-rich atmospheres oxygen and ozone may build up to levels that have conventionally been accepted as signatures of life, if there is no surface emission of reducing gases. The atmospheric scenarios presented in this paper can serve as the benchmark atmospheres for quickly assessing the lifetime of trace gases in reducing, weakly oxidizing, and highly oxidizing atmospheres on terrestrial exoplanets for the exploration of possible biosignature gases.

  5. Global 3-D model analysis of the seasonal cycle of atmospheric carbonyl sulfide: Implications for terrestrial vegetation uptake

    E-Print Network [OSTI]

    Jacob, Daniel J.

    Global 3-D model analysis of the seasonal cycle of atmospheric carbonyl sulfide: Implications of atmospheric carbonyl sulfide (COS) to interpret observations at a network of surface sites. We aim to identify, and D. J. Jacob (2008), Global 3-D model analysis of the seasonal cycle of atmospheric carbonyl sulfide

  6. The sensitivity of the PSU-NCAR model (MM5) to cumulus parameterization in simulating the mesoscale environment associated with 2 June 1995 West Texas tornado outbreak 

    E-Print Network [OSTI]

    Han, Sang-Ok

    1998-01-01

    important role in producing tornadic supercedes. This study presents observational features of the event, performs model simulations with three disparate cumulus parameterization schemes, and does a careful comparison between the simulations and observations...

  7. Mesoscale coupled ocean-atmosphere feedbacks in boundary current systems

    E-Print Network [OSTI]

    Putrasahan, Dian Ariyani

    2012-01-01

    productive oceanic eastern boundary current, providing anCurrent System and the Kuroshio Extension uses OFES products for their oceanic

  8. Mesoscale coupled ocean-atmosphere feedbacks in boundary current systems

    E-Print Network [OSTI]

    Putrasahan, Dian Ariyani

    2012-01-01

    N/m 2 per 10000km) against crosswind SST gradients ( ? C peroverlaid with contours crosswind SST gradients ( ? C perpositive (negative) crosswind SST gradients at 0.4 ? C per

  9. Mesoscale coupled ocean-atmosphere feedbacks in boundary current systems

    E-Print Network [OSTI]

    Putrasahan, Dian Ariyani

    2012-01-01

    a shifted maximum wind stress offshore when compare to Fig.strengthening winds while extending offshore. A seasonalthe shift of wind stress peak offshore (Fig. 3.30) changes

  10. Mesoscale coupled ocean-atmosphere feedbacks in boundary current systems

    E-Print Network [OSTI]

    Putrasahan, Dian Ariyani

    2012-01-01

    to about 600km offshore, beyond which wind stress curla shifted maximum wind stress offshore when compare to Fig.strengthening winds while extending offshore. A seasonal

  11. ESA White paper: Atmospheric modeling: Setting Biomarkers in context

    E-Print Network [OSTI]

    L. Kaltenegger; F. Selsis

    2008-09-23

    Motivation: ESAs goal to detect biomarkers in Earth-like exoplanets in the Habitable Zone requires theoretical groundwork that needs to be done to model the influence of different parameters on the detectable biomarkers. We need to model a wide parameter space (chemical composition, pressure, evolution, interior structure and outgassing, clouds) to generate a grid of models that inform our detection strategy as well as can help characterize the spectra of the small rocky planets detected.

  12. Investigation of the Summer Climate of the Contiguous United States and Mexico Using the Regional Atmospheric Modeling System (RAMS).

    E-Print Network [OSTI]

    Castro, Christopher L.

    to observations. The Great Plains low-level jet (LLJ) is also well represented in both RAMS and NARR, but the Baja Atmospheric Modeling System (RAMS). Part I: Model Climatology (1950­2002) CHRISTOPHER L. CASTRO* Department downscaled using the Regional Atmospheric Modeling System (RAMS) to generate a regional climate model (RCM

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

    E-Print Network [OSTI]

    Aneja, Viney P.

    . Keywords: ammonia, emission, mass transfer, modelling, swine waste storage and treatment system 1MEASUREMENT AND MODELLING OF AMMONIA EMISSIONS AT WASTE TREATMENT LAGOON-ATMOSPHERIC INTERFACE of ammonia are approximately 75 Tg N/yr (1 Tg = 1012g). The major global source is excreta from domestic

  14. Interpretation of AIRS Data in Thin Cirrus Atmospheres Based on a Fast Radiative Transfer Model

    E-Print Network [OSTI]

    Liou, K. N.

    Interpretation of AIRS Data in Thin Cirrus Atmospheres Based on a Fast Radiative Transfer Model of California, Los Angeles, Los Angeles, California B. H. KAHN Jet Propulsion Laboratory, California Institute radiative transfer model has been developed for application to cloudy satellite data assimilation

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

    E-Print Network [OSTI]

    Holmes, Christopher D.

    by atomic bromine (Br) in the tropo- sphere by combining kinetic data for the Hg-Br system with modeledMultiscale models of atmospheric mercury: bromine chemistry, air-sea exchange, and global transport rights reserved. #12;iii Dissertation Advisor Author Professor Daniel J. Jacob Christopher D. Holmes

  16. A Data System for Visualizing 4-D Atmospheric CO2 Models and Data

    E-Print Network [OSTI]

    Michalak, Anna M.

    A Data System for Visualizing 4-D Atmospheric CO2 Models and Data Tyler A. Erickson Michigan Tech CO2 Models and Data Abstract This paper describes a geospatial data system that produces KML.michalak@umich.edu John C. Lin Department of Earth and Environmental Sciences University of Waterloo 200 University Avenue

  17. Proceedings of the 51st Anniversary Conference of KSME PHYSICAL MODELING OF ATMOSPHERIC FLOW

    E-Print Network [OSTI]

    White, Bruce

    a model house in a small wind tunnel to measure wind pressure against the model. Since then, many attempts over tall buildings. The temperature differences within the atmospheric boundary layer affect both wind is discussed with special emphasis on wind-tunnel simulation techniques. The governing equations of motion

  18. Land Surface Model Data Assimilation for Atmospheric Prediction

    E-Print Network [OSTI]

    Walker, Jeff

    predictions from different models even when using the same parameters, inputs, and initial conditions (Houser remote sensing studies, using visible, thermal infrared (surface temperature) and microwave (passive and active) electromagnetic radiation. Of these, passive microwave soil moisture measurement has been

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

    E-Print Network [OSTI]

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

    2013-01-01

    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.

  20. MODELING ATMOSPHERIC RELEASES OF TRITIUM FROM NUCLEAR INSTALLATIONS

    SciTech Connect (OSTI)

    Okula, K

    2007-01-17

    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.

  1. A Flexible Atmospheric Modeling Framework for the CESM

    SciTech Connect (OSTI)

    Randall, David; Heikes, Ross; Konor, Celal

    2014-11-12

    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.

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

    E-Print Network [OSTI]

    Thomas Rauch

    2003-03-20

    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.

  3. A mesoscale analysis of the Rayleigh-Plateau instability.

    SciTech Connect (OSTI)

    Pao, Wenxiao (BU); Soteriou, Marios (UTRC); Li, Xiaoyi (UTRC); Karniadakis, George (BU); Arienti, Marco

    2010-11-01

    Capillary pinch-off results carried out with the Many-Body Dissipative Particle Dynamics (MDPD) method are compared with the two-phase continuum discretization of hydrodynamics. The MDPD method provides a mesoscale description of the liquid-gas interface -- molecules can be thought of as grouped in particles with modeled Brownian and dissipative effects. No liquid-gas interface is explicitly defined; surface properties, such as surface tension, result from the MDPD interaction parameters. In side-to-side comparisons, the behavior of the MDPD liquid is demonstrated to replicate the macroscale behavior (thin interface assumption) calculated by the Combined Level Set-Volume of Fluid (CLSVOF) method. For instance, in both the continuum and mesoscale discretizations the most unstable wavelength perturbation leads to pinch-off, whereas a smaller wavelength-to-diameter ratio, as expected, does not. The behavior of the virial pressure in MDPD will be discussed in relation to the hydrodynamic capillary pressure that results from the thin interface assumption.

  4. Geosci. Model Dev., 6, 12751298, 2013 www.geosci-model-dev.net/6/1275/2013/

    E-Print Network [OSTI]

    Boyer, Edmond

    for the 3-D cloud-resolving mesoscale model Meso-NH with application to idealized cases M. Leriche, J-dimensional cloud resolv- ing mesoscale model. This module includes gaseous- and aqueous-phase chemical reactions

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

    E-Print Network [OSTI]

    Friedman, Carey

    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 model’s ability to simulate PAHs with different volatilities, ...

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

    SciTech Connect (OSTI)

    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

    2014-01-01

    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.

  7. Mesoscale harmonic analysis of homogenous dislocation nucleation

    E-Print Network [OSTI]

    Asad Hasan; Craig E. Maloney

    2012-05-08

    We perform atomistic computer simulations to study the mechanism of homogeneous dislocation nucleation in two dimensional (2D) hexagonal crystalline films during indentation with a circular nanoindenter. The nucleation process is governed by the vanishing of the energy associated with a single normal mode. This critical mode is largely confined to a single plane of adjacent atoms. For fixed film thickness, L, the spatial extent, \\xi, of the critical mode grows with indenter radius, R. For fixed R/L, the spatial extent \\xi, grows roughly as \\xi ~ L^0.4. We, furthermore, perform a mesoscale analysis to determine the lowest energy normal mode for mesoscale regions of varying radius, r_{meso}, centered on the critical mode's core. The energy, \\lambda_{meso}, of the lowest normal mode in the meso-region decays very rapidly with r_{meso} and \\lambda_{meso} ~= 0 for r_{meso} >~ \\xi. The lowest normal mode shows a spatial extent, \\xi_{meso}, which has a sublinear power-law increase with r_{meso} for r_{meso} mesoscale analysis gives good estimates for the energy and spatial extent of the critical mode \\emph{only} for r_{meso} >~ 1.5 \\xi. In this sense homogeneous dislocation nucleation should be understood as a quasi-local phenomenon.

  8. Observational Analysis of the Predictability of Mesoscale Convective Systems ISRAEL L. JIRAK AND WILLIAM R. COTTON

    E-Print Network [OSTI]

    Observational Analysis of the Predictability of Mesoscale Convective Systems ISRAEL L. JIRAK (Manuscript received 30 December 2005, in final form 4 October 2006) ABSTRACT Mesoscale convective systems of usefulness in operational forecasting. 1. Introduction Mesoscale convective systems (MCSs) frequently de

  9. MESOSCALE OCEANOGRAPHY Instructors: Igor Kamenkovich, Arthur Mariano and Donald B. Olson, with other contributions

    E-Print Network [OSTI]

    Miami, University of

    MESOSCALE OCEANOGRAPHY Instructors: Igor Kamenkovich, Arthur Mariano and Donald B. Olson of ocean mesoscale variability, including its properties in different oceanic regimes, the dynamics will learn basic concepts on ocean mesoscale processes and perspectives on current research topics from

  10. Detecting and characterizing mesoscale and submesoscale structures of Mediterranean water from joint seismic

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Click Here for Full Article Detecting and characterizing mesoscale and submesoscale structures mesoscale and submesoscale structures of Mediterranean water from joint seismic and hydrographic the imaged structures in terms of mesoscale and submesoscale eddies, of homogeneous layers and of lateral

  11. Modeling Activities in the Department of Energy’s Atmospheric Sciences Program

    SciTech Connect (OSTI)

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

    2009-03-01

    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.

  12. ATMOSPHERIC MODELING IN SUPPORT OF A ROADWAY ACCIDENT

    SciTech Connect (OSTI)

    Buckley, R.; Hunter, C.

    2010-10-21

    The United States Forest Service-Savannah River (USFS) routinely performs prescribed fires at the Savannah River Site (SRS), a Department of Energy (DOE) facility located in southwest South Carolina. This facility covers {approx}800 square kilometers and is mainly wooded except for scattered industrial areas containing facilities used in managing nuclear materials for national defense and waste processing. Prescribed fires of forest undergrowth are necessary to reduce the risk of inadvertent wild fires which have the potential to destroy large areas and threaten nuclear facility operations. This paper discusses meteorological observations and numerical model simulations from a period in early 2002 of an incident involving an early-morning multicar accident caused by poor visibility along a major roadway on the northern border of the SRS. At the time of the accident, it was not clear if the limited visibility was due solely to fog or whether smoke from a prescribed burn conducted the previous day just to the northwest of the crash site had contributed to the visibility. Through use of available meteorological information and detailed modeling, it was determined that the primary reason for the low visibility on this night was fog induced by meteorological conditions.

  13. From Quanta to the Continuum: Opportunities for Mesoscale Science...

    Office of Scientific and Technical Information (OSTI)

    Quanta to the Continuum: Opportunities for Mesoscale Science Crabtree, George Argonne National Lab. (ANL), Argonne, IL (United States); Sarrao, John Los Alamos National Lab....

  14. Challenge of Dynamic Mesoscale Imaging Barnes, Cris William ...

    Office of Scientific and Technical Information (OSTI)

    The Matter-Radiation Interactions in Extremes Project, and the Challenge of Dynamic Mesoscale Imaging Barnes, Cris William Los Alamos National Laboratory; Barber, John L. Los...

  15. Quanta to the Continuum: Opportunities for Mesoscale Science...

    Office of Scientific and Technical Information (OSTI)

    Quanta to the Continuum: Opportunities for Mesoscale Science Sarrao, John L Los Alamos National Laboratory; Crabtree, George Argonne National Laboratory 36 MATERIALS SCIENCE;...

  16. Meso-Scale during Electron Beam Additive Manufacturing Chen,...

    Office of Scientific and Technical Information (OSTI)

    Thermal Properties and Beam-Particle Interaction at Meso-Scale during Electron Beam Additive Manufacturing Chen, Jian ORNL ORNL; Zheng, Lili ORNL ORNL; Feng, Zhili...

  17. Numerical Simulation in Applied Geophysics. From the Mesoscale to ...

    E-Print Network [OSTI]

    Local variations in the fluid and solid matrix properties, fine layering, fractures and craks at the mesoscale (on the order of centimeters) are common in the earth's ...

  18. Radio frequency induced ionized collisional flow model for application at atmospheric pressures

    E-Print Network [OSTI]

    Roy, Subrata

    Radio frequency induced ionized collisional flow model for application at atmospheric pressures and radio frequency (rf) induced plasma-sheath dynamics, using multifluid equations. For the former, argon inherent in nonequilibrium discharges such as obtained through radio frequency (rf) or microwave excitation

  19. Observations and modelling of the global distribution and long-term trend of atmospheric 14

    E-Print Network [OSTI]

    (IWR), University of Heidelberg, INF 368, D-69120 Heidelberg, Germany, now at Electrical Engineering for Australian Weather and Climate Research / CSIRO Marine and Atmospheric Research (CMAR), Private Bag No. 1 and sinks, using the coarse-grid carbon cycle model GRACE. Dedicated simulations of global trends and inter

  20. Atmospheric Environment 39 (2005) 13731382 A hierarchical Bayesian model to estimate and forecast ozone

    E-Print Network [OSTI]

    Irwin, Mark E.

    2005-01-01

    conditional on observed (or forecasted) meteorology including temperature, humidity, pressure, and wind speed, defining the spatial­temporal extent of episodes of dangerous air quality, forecasting urban and areaAtmospheric Environment 39 (2005) 1373­1382 A hierarchical Bayesian model to estimate and forecast

  1. Modeling atmospheric effects of the September 1859 solar flare B. C. Thomas,1

    E-Print Network [OSTI]

    Jackman, Charles H.

    Modeling atmospheric effects of the September 1859 solar flare B. C. Thomas,1 C. H. Jackman,2 and A. Melott(2007),ModelingatmosphericeffectsoftheSeptember1859 solar flare, Geophys. Res. Lett., 34, L06810 of the work in this area. [3] The solar flare of 1 September 1859 was one of the most intense white

  2. Measurements and Modeling of Atmospheric Pollution over the Paris Area: An Overview of the ESQUIF Project

    E-Print Network [OSTI]

    Menut, Laurent

    project As in many big cities throughout the world, pollution levels in the Paris area due to concentratedMeasurements and Modeling of Atmospheric Pollution over the Paris Area: An Overview of the ESQUIF) project is the first integrated project dedicated to the study of the processes leading to air pollution

  3. MODELLING MODIFIED ATMOSPHERE PACKAGING FOR FRUITS AND VEGETABLES USING MEMBRANE SYSTEMS

    E-Print Network [OSTI]

    Hinze, Thomas

    of polymeric film in or- der to modify the O2 and CO2 concentrations inside the package, reducing metabolic are not fully under- stood. As examples we can refer to the little knowl- edge about the effect of CO2MODELLING MODIFIED ATMOSPHERE PACKAGING FOR FRUITS AND VEGETABLES USING MEMBRANE SYSTEMS Gabi

  4. Comparison of model estimates of the effects of aviation emissions on atmospheric ozone and methane

    E-Print Network [OSTI]

    Jacobson, Mark

    of the world econ- omy and demand for aviation and its emissions are expected to increase in the future from aviation (mainly carbon dioxide (CO2), water vapor (H2O), nitrogen oxides (NOx = NO + NO2), VOCsComparison of model estimates of the effects of aviation emissions on atmospheric ozone and methane

  5. Mesoscale polycrystal calculations of damage in spallation in metals

    SciTech Connect (OSTI)

    Tonks, Davis L [Los Alamos National Laboratory; Bingert, John F [Los Alamos National Laboratory; Livescu, Veronica [Los Alamos National Laboratory; Luo, Shengnian [Los Alamos National Laboratory; Bronkhorst, C A [Los Alamos National Laboratory

    2010-01-01

    The goal of this project is to produce a damage model for spallation in metals informed by the polycrystalline grain structure at the mesoscale. Earlier damage models addressed the continuwn macroscale in which these effects were averaged out. In this work we focus on cross sections from recovered samples examined with EBSD (electron backscattered diffraction), which reveal crystal grain orientations and voids. We seek to understand the loading histories of specific sample regions by meshing up the crystal grain structure of these regions and simulating the stress, strain, and damage histories in our hydro code, FLAG. The stresses and strain histories are the fundamental drivers of damage and must be calculated. The calculated final damage structures are compared with those from the recovered samples to validate the simulations.

  6. Lagrangian study of transport and mixing in a mesoscale eddy street

    E-Print Network [OSTI]

    S. V. Prants; M. V. Budyansky; V. I. Ponomarev; M. Yu. Uleysky

    2012-02-02

    We use dynamical systems approach and Lagrangian tools to study surface transport and mixing of water masses in a selected coastal region of the Japan Sea with moving mesoscale eddies associated with the Primorskoye Current. Lagrangian trajectories are computed for a large number of particles in an interpolated velocity field generated by a numerical regional multi-layer eddy-resolving circulation model. We compute finite-time Lyapunov exponents for a comparatively long period of time by the method developed and plot the Lyapunov synoptic map quantifying surface transport and mixing in that region. This map uncovers the striking flow structures along the coast with a mesoscale eddy street and repelling material lines. We propose new Lagrangian diagnostic tools --- the time of exit of particles off a selected box, the number of changes of the sign of zonal and meridional velocities --- to study transport and mixing by a pair of strongly interacting eddies often visible at sea-surface temperature satellite images in that region. We develop a technique to track evolution of clusters of particles, streaklines and material lines. The Lagrangian tools used allow us to reveal mesoscale eddies and their structure, to track different phases of the coastal flow, to find inhomogeneous character of transport and mixing on mesoscales and submesoscales and to quantify mixing by the values of exit times and the number of times particles wind around the eddy's center.

  7. Nano- and mesoscale modeling of cement matrix

    E-Print Network [OSTI]

    Yu, Zechuan

    Atomistic simulations of cementitious material can enrich our understanding of its structural and mechanical properties, whereas current computational capacities restrict the investigation length scale within 10 nm. In ...

  8. Atomistic and mesoscale modeling of dislocation mobility

    E-Print Network [OSTI]

    Cai, Wei, 1977-

    2001-01-01

    Dislocation is a line defect in crystalline materials, and a microscopic carrier of plastic deformation. Because dislocation has both a localized core and a long-range stress field, linking atomistic and meso scales is ...

  9. Mesoscale Modeling Framework Design: Subcontract Report Chen...

    Office of Scientific and Technical Information (OSTI)

    Tang, M; Heo, T W; Wood, B C 36 MATERIALS SCIENCE; 77 NANOSCIENCE AND NANOTECHNOLOGY; 25 ENERGY STORAGE Abstract not provided Lawrence Livermore National Laboratory (LLNL),...

  10. Mesoscale regulation comes from the bottom-up: intertidal interactions between consumers

    E-Print Network [OSTI]

    Nielsen, Karina J.

    REPORT Mesoscale regulation comes from the bottom-up: intertidal interactions between consumers variation in nutrient supply to shift community structure over mesoscales. Keywords Macroalgae, upwelling

  11. Mesoscale simulation of polymer reaction equilibrium: Combining dissipative particle dynamics with reaction

    E-Print Network [OSTI]

    Lisal, Martin

    Mesoscale simulation of polymer reaction equilibrium: Combining dissipative particle dynamics. R. Smith, J. Chem. Phys. 125, 16490 2006 , a mesoscale simulation technique for studying polymer

  12. NASA-TM-III642 Design of Inielligent Mesoscale Periodic Array

    E-Print Network [OSTI]

    Asher, Sanford A.

    i" /} , NASA-TM-III642 Design of Inielligent Mesoscale Periodic Array Structures Utilizing Smart *National Research Council hitrodoetion Mesoscale Periodic Arlay Structures (MPAS, also known as crystalline

  13. A unified morphological description of Nafion membranes from SAXS and mesoscale simulations

    E-Print Network [OSTI]

    Elliott, James

    A unified morphological description of Nafion membranes from SAXS and mesoscale simulations James A with mesoscale simulations of the morphology of Nafion using Dissipative Particle Dynamics (DPD) parameterized

  14. Mesoscale Theory of Grains and Cells: Crystal Plasticity and Coarsening Surachate Limkumnerd* and James P. Sethna

    E-Print Network [OSTI]

    Sethna, James P.

    Mesoscale Theory of Grains and Cells: Crystal Plasticity and Coarsening Surachate Limkumnerd a mesoscale theory of dislocation motion. It provides a quantitative description of deformation and rotation

  15. Atmospheric Modelling for Neptune's Methane D/H Ratio - Preliminary Results

    E-Print Network [OSTI]

    Cotton, Daniel V; Bott, Kimberly; Bailey, Jeremy

    2015-01-01

    The ratio of deuterium to hydrogen (D/H ratio) of Solar System bodies is an important clue to their formation histories. Here we fit a Neptunian atmospheric model to Gemini Near Infrared Spectrograph (GNIRS) high spectral resolution observations and determine the D/H ratio in methane absorption in the infrared H-band ($\\sim$ 1.6 {\\mu}m). The model was derived using our radiative transfer software VSTAR (Versatile Software for the Transfer of Atmospheric Radiation) and atmospheric fitting software ATMOF (ATMOspheric Fitting). The methane line list used for this work has only become available in the last few years, enabling a refinement of earlier estimates. We identify a bright region on the planetary disc and find it to correspond to an optically thick lower cloud. Our preliminary determination of CH$_{\\rm 3}$D/CH$_{\\rm 4}$ is 3.0$\\times10^{-4}$, which is in line with the recent determination of Irwin et al. (2014) of 3.0$^{+1.0}_{-0.9}\\sim\\times10^{-4}$, made using the same model parameters and line list but...

  16. Evaluation of dynamical parameters with a three-dimensional mechanistic model of the middle atmosphere

    SciTech Connect (OSTI)

    Kouker, W. [Institut fuer Meteorologie und Klimaforschung, Karlsruhe (Germany)

    1993-12-01

    A three-dimensional model of the middle atmosphere is introduced. The model is based on the full set of the primitive equations. It is designed to simulate a yearly cycle of the middle atmosphere. Results are presented for the solstice and equinox conditions. The model reproduces the main observed features of the middle atmospheric circulation: the stratospheric-mesospheric jet streams and the cold summer mesopause region at solstice with reversed zonal wind especially in the summer mesosphere, and the weak westerly circulation at equinox. The parameterized effects of breaking gravity waves in the mesosphere drive the atmosphere out of radiative balance. They lead to a meridional circulation with a one-cell structure at solstice with upward (downward) motion over the summer (winter) pole and a meridional flow towards the winter hemisphere and a two-cell structure at equinox with upward motion over the tropics and downward motion over the polar regions. Potential fields are presented for horizontal vector fields. They suggest that the stratospheric circulation can is dominated by horizontally nondivergent flow. This is modified by the results of a more quantitative view at the interaction of planetary waves on the zonal mean flow, which clearly identifies the essential role of horizontal divergence on the stratospheric circulation.

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

    SciTech Connect (OSTI)

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

    2014-09-01

    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.

  18. Simulation of polar stratospheric clouds in the specified dynamics version of the whole atmosphere community climate model

    E-Print Network [OSTI]

    Wegner, T.

    We evaluate the simulation of polar stratospheric clouds (PSCs) in the Specified Dynamics version of the Whole Atmosphere Community Climate Model for the Antarctic winter 2005. In this model, PSCs are assumed to form ...

  19. Edinburgh Research Explorer A simulator for spatially extended kappa models

    E-Print Network [OSTI]

    Millar, Andrew J.

    ., 2003) to the Kappa framework. This positions SK among other meso-scale modelling techniques, e.g. Meso

  20. Generation of mesoscale convective structures in tokamak edge plasma

    SciTech Connect (OSTI)

    Krasheninnikov, S. I.; Smolyakov, A. I. [University of California at San Diego, 9500 Gilman Drive, La Jolla, California 92093 (United States); University of Saskatchewan, 116 Science Place, Saskatoon, Saskatchewan S7N 5E2 (Canada)

    2007-10-15

    It is shown that the interplay of the interchange drive and nonlinear effects of Reynolds stress and inverse cascade of drift wave turbulence select a range of plasma parameters (plasma pressure), for which mesoscale perturbations of a certain transverse length scale become unstable. It is suggested that the blob formation is a result of these mesoscale instabilities.

  1. THE GREAT OXIDATION OF EARTH'S ATMOSPHERE: CONTESTING THE YOYO MODEL VIA TRANSITION STABILITY ANALYSIS

    SciTech Connect (OSTI)

    Cuntz, M.; Roy, D.; Musielak, Z. E., E-mail: cuntz@uta.ed, E-mail: dipanjan.roy@etumel.univmed.f, E-mail: zmusielak@uta.ed [Department of Physics, University of Texas at Arlington, Arlington, TX 76019 (United States)

    2009-11-20

    A significant controversy regarding the climate history of the Earth and its relationship to the development of complex life forms concerns the rise of oxygen in the early Earth's atmosphere. Geological records show that this rise occurred about 2.4 Gyr ago, when the atmospheric oxygen increased from less than 10{sup -5} present atmospheric level (PAL) to more than 0.01 PAL and possibly above 0.1 PAL. However, there is a debate whether this rise happened relatively smoothly or with well-pronounced ups and downs (the Yoyo model). In our study, we explore a simplified atmospheric chemical system consisting of oxygen, methane, and carbon that is driven by the sudden decline of the net input of reductants to the surface as previously considered by Goldblatt et al. Based on the transition stability analysis for the system equations, constituting a set of non-autonomous and non-linear differential equations, as well as the inspection of the Lyapunov exponents, it is found that the equations do not exhibit chaotic behavior. In addition, the rise of oxygen occurs relative smoothly, possibly with minor bumps (within a factor of 1.2), but without major jumps. This result clearly argues against the Yoyo model in agreement with recent geological findings.

  2. 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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 OutreachProductswsicloudwsiclouddenDVA N C E D B L O O DBiomass and BiofuelsPhysicist47 Industrial1 -AtDust as

  3. 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]

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

    2015-01-01

    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 ...

  4. Estimating Bacteria Emissions from Inversion of Atmospheric Transport: Sensitivity to Modelled Particle Characteristics

    SciTech Connect (OSTI)

    Burrows, Susannah M.; Rayner, Perter; Butler, T.; Lawrence, M.

    2013-06-04

    Model-simulated transport of atmospheric trace components can be combined with observed concentrations to obtain estimates of ground-based sources using various inversion techniques. These approaches have been applied in the past primarily to obtain source estimates for long-lived trace gases such as CO2. We consider the application of similar techniques to source estimation for atmospheric aerosols, by using as a case study the estimation of bacteria emissions from different ecosystem regions in the global atmospheric chemistry and climate model ECHAM5/MESSy-Atmospheric Chemistry (EMAC). Simulated particle concentrations in the tropopause region and at high latitudes, as well as transport of particles to tundra and land ice regions are shown to be highly sensitive to scavenging in mixed-phase clouds, which is poorly characterized in most global climate models. This may be a critical uncertainty in correctly simulating the transport of aerosol particles to the Arctic. Source estimation via Monte Carlo Markov Chain is applied to a suite of sensitivity simulations and the global mean emissions are estimated. We present an analysis of the partitioning of uncertainties in the global mean emissions that are attributable to particle size, CCN activity, the ice nucleation scavenging ratios for mixed-phase and cold clouds, and measurement error. Uncertainty due to CCN activity or to a 1 um error in particle size is typically between 10% and 40% of the uncertainty due to data uncertainty, as measured by the 5%-ile to 95%-ile range of the Monte Carlo ensemble. Uncertainty attributable to the ice nucleation scavenging ratio in mized-phase clouds is as high as 10% to 20% of the data uncertainty. Taken together, the four model 20 parameters examined contribute about half as much to the uncertainty in the estimated emissions as do the measurements. This was a surprisingly large contribution from model uncertainty in light of the substantial data uncertainty, which ranges from 81% to 870% for each of ten ecosystems for this case study. The effects of these and other model parameters in contributing to the uncertainties in the transport of atmospheric aerosol particles should be treated explicitly and systematically in both forward and inverse modelling studies.

  5. 3D cut-cell modelling for high-resolution atmospheric simulations

    E-Print Network [OSTI]

    Yamazaki, H; Nikiforakis, N

    2015-01-01

    With the recent, rapid development of computer technology, the resolution of atmospheric numerical models has increased substantially. As a result, steep gradients in mountainous terrain are now being resolved in high-resolution models. This results in large truncation errors in those models using terrain-following coordinates. In this study, a new 3D Cartesian coordinate non-hydrostatic atmospheric model is developed. A cut-cell representation of topography based on finite-volume discretization is combined with a cell-merging approach, in which small cut-cells are merged with neighboring cells either vertically or horizontally. In addition, a block-structured mesh-refinement technique achieves a variable resolution on the model grid with the finest resolution occurring close to the terrain surface. The model successfully reproduces a flow over a 3D bell-shaped hill that shows a good agreement with the flow predicted by the linear theory. The ability of the model to simulate flows over steep terrain is demons...

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

    SciTech Connect (OSTI)

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

    2014-09-08

    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.

  7. A moist aquaplanet variant of the Held–Suarez test for atmospheric model dynamical cores

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Thatcher, D. R.; Jablonowski, C.

    2015-09-29

    A moist idealized test case (MITC) for atmospheric model dynamical cores is presented. The MITC is based on the Held–Suarez (HS) test that was developed for dry simulations on a flat Earth and replaces the full physical parameterization package with a Newtonian temperature relaxation and Rayleigh damping of the low-level winds. This new variant of the HS test includes moisture and thereby sheds light on the non-linear dynamics-physics moisture feedbacks without the complexity of full physics parameterization packages. In particular, it adds simplified moist processes to the HS forcing to model large-scale condensation, boundary layer mixing, and the exchange ofmore »latent and sensible heat between the atmospheric surface and an ocean-covered planet. Using a variety of dynamical cores of NCAR's Community Atmosphere Model (CAM), this paper demonstrates that the inclusion of the moist idealized physics package leads to climatic states that closely resemble aquaplanet simulations with complex physical parameterizations. This establishes that the MITC approach generates reasonable atmospheric circulations and can be used for a broad range of scientific investigations. This paper provides examples of two application areas. First, the test case reveals the characteristics of the physics-dynamics coupling technique and reproduces coupling issues seen in full-physics simulations. In particular, it is shown that sudden adjustments of the prognostic fields due to moist physics tendencies can trigger undesirable large-scale gravity waves, which can be remedied by a more gradual application of the physical forcing. Second, the moist idealized test case can be used to intercompare dynamical cores. These examples demonstrate the versatility of the MITC approach and suggestions are made for further application areas. The new moist variant of the HS test can be considered a test case of intermediate complexity.« less

  8. Hubble Space Telescope Observations of SV Cam: II. First Derivative Lightcurve Modelling using PHOENIX and ATLAS Model Atmospheres

    E-Print Network [OSTI]

    S. V. Jeffers; J. P. Aufdenberg; G. A. J. Hussain; A. Collier Cameron; V. R. Holzwarth

    2006-02-02

    The variation of the specific intensity across the stellar disc is essential input parameter in surface brightness reconstruction techniques such as Doppler imaging, where the relative intensity contributions of different surface elements are important in detecting starspots. We use PHOENIX and ATLAS model atmospheres to model lightcurves derived from high precision (S/N ~ 5000) HST data of the eclipsing binary SV Cam (F9V + K4V), where the variation of specific intensity across the stellar disc will determine the contact points of the binary system lightcurve. For the first time we use chi^2 comparison fits to the first derivative profiles to determine the best-fitting model atmosphere. We show the wavelength dependence of the limb darkening and that the first derivative profile is sensitive to the limb-darkening profile very close to the limb of the primary star. It is concluded that there is only a marginal difference (< 1sigma) between the chi^2 comparison fits of the two model atmospheres to the HST lightcurve at all wavelengths. The usefulness of the second derivative of the light-curve for measuring the sharpness of the primary's limb is investigated, but we find that the data are too noisy to permit a quantitative analysis.

  9. A probabilistic model for bounded elasticity tensor random fields with application to polycrystalline

    E-Print Network [OSTI]

    Boyer, Edmond

    -bounded positive-definite matrix-valued random fields in the context of mesoscale modeling of heterogeneous elastic; Heterogeneous materials; Apparent elasticity tensor; Mesoscale modeling; Random field; Non-Gaussian. $ J

  10. Modeling Stellar Atmospheres with a Spherically Symmetric Version of the Atlas Code: Testing the Code by Comparisons to Interferometric Observations and PHOENIX Models

    E-Print Network [OSTI]

    Hilding R. Neilson; John B. Lester

    2008-09-01

    One of the current opportunities for stellar atmospheric modeling is the interpretation of optical interferometric data of stars. Starting from the robust, open source ATLAS atmospheric code (Kurucz, 1979), we have developed a spherically symmetric code, SATLAS, as a new option for modeling stellar atmospheres of low gravity stars. The SATLAS code is tested against both interferometric observations of M giants by Wittkowski and collaborators, and spherically symmetric M giant NextGen models from the PHOENIX code. The SATLAS models predict interferometric visibilities that agree with the observed visibilities and with predicted visibilities, and the SATLAS atmospheric structures also agree with those from spherical PHOENIX models, with just small differences in temperature and pressure at large depths in the atmospheres.

  11. Aerosol specification in single-column Community Atmosphere Model version 5

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Lebassi-Habtezion, B.; Caldwell, P. M.

    2015-03-27

    Single-column model (SCM) capability is an important tool for general circulation model development. In this study, the SCM mode of version 5 of the Community Atmosphere Model (CAM5) is shown to handle aerosol initialization and advection improperly, resulting in aerosol, cloud-droplet, and ice crystal concentrations which are typically much lower than observed or simulated by CAM5 in global mode. This deficiency has a major impact on stratiform cloud simulations but has little impact on convective case studies because aerosol is currently not used by CAM5 convective schemes and convective cases are typically longer in duration (so initialization is less important).more »By imposing fixed aerosol or cloud-droplet and crystal number concentrations, the aerosol issues described above can be avoided. Sensitivity studies using these idealizations suggest that the Meyers et al. (1992) ice nucleation scheme prevents mixed-phase cloud from existing by producing too many ice crystals. Microphysics is shown to strongly deplete cloud water in stratiform cases, indicating problems with sequential splitting in CAM5 and the need for careful interpretation of output from sequentially split climate models. Droplet concentration in the general circulation model (GCM) version of CAM5 is also shown to be far too low (~ 25 cm?3) at the southern Great Plains (SGP) Atmospheric Radiation Measurement (ARM) site.« less

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

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Scanza, R. A.; Mahowald, N.; Ghan, S.; Zender, C. S.; Kok, J. F.; Liu, X.; Zhang, Y.

    2014-07-02

    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 componentsmore »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 +0.05 W m?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 +0.17 W m?2) and of dust with optimized optical properties, wet scavenging and particle size distribution in CAM4 and CAM5, ?0.05 and ?0.17 W m?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.« less

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

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

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

    2015-01-01

    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 componentsmore »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 + 0.05 Wm?² for both CAM4 and CAM5 simulations with mineralogy. We compare this to the radiative forcing from simulations of dust in release versions of CAM4 and CAM5 (+0.08 and +0.17 Wm?²) and of dust with optimized optical properties, wet scavenging and particle size distribution in CAM4 and CAM5, -0.05 and -0.17 Wm?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.« less

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

    SciTech Connect (OSTI)

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

    2015-01-01

    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 + 0.05 Wm?² for both CAM4 and CAM5 simulations with mineralogy. We compare this to the radiative forcing from simulations of dust in release versions of CAM4 and CAM5 (+0.08 and +0.17 Wm?²) and of dust with optimized optical properties, wet scavenging and particle size distribution in CAM4 and CAM5, -0.05 and -0.17 Wm?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.

  15. 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]

    Dutkiewicz, Stephanie.

    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 ...

  16. Lagrangian study of transport and mixing in a mesoscale eddy street

    E-Print Network [OSTI]

    Prants, S V; Ponomarev, V I; Uleysky, M Yu; 10.1016/j.ocemod.2011.02.008

    2012-01-01

    We use dynamical systems approach and Lagrangian tools to study surface transport and mixing of water masses in a selected coastal region of the Japan Sea with moving mesoscale eddies associated with the Primorskoye Current. Lagrangian trajectories are computed for a large number of particles in an interpolated velocity field generated by a numerical regional multi-layer eddy-resolving circulation model. We compute finite-time Lyapunov exponents for a comparatively long period of time by the method developed and plot the Lyapunov synoptic map quantifying surface transport and mixing in that region. This map uncovers the striking flow structures along the coast with a mesoscale eddy street and repelling material lines. We propose new Lagrangian diagnostic tools --- the time of exit of particles off a selected box, the number of changes of the sign of zonal and meridional velocities --- to study transport and mixing by a pair of strongly interacting eddies often visible at sea-surface temperature satellite imag...

  17. Engineering mesoscale structures with distinct dynamical implications in networks of delay-coupled delay oscillators

    E-Print Network [OSTI]

    Anne-Ly Do; Johannes Höfener; Thilo Gross

    2012-07-05

    The dynamics of networks of interacting systems depends intricately on the interaction topology. When the dynamics is explored, generally the whole topology has to be considered. However, we show that there are certain mesoscale subgraphs that have precise and distinct consequences for the system-level dynamics. In particular, if meso-scale symmetries are present then eigenvectors of the Jacobian localise on the symmetric subgraph and the corresponding eigenvalues become insensitive to the topology outside the subgraph. Hence, dynamical instabilities associated with these eigenvalues can be analyzed without considering the topology outside the subgraph. While such instabilities are thus generated entirely in small network subgraphs, they generally do not remain confined to the subgraph once the instability sets in and thus have system-level consequences. Here we illustrate the analytical investigation of such instabilities in an ecological meta-population model consisting of a network of delay-coupled delay oscillators.

  18. Mathematical model of influence of topography on the large atmospheric vortex motion

    E-Print Network [OSTI]

    Rozanova, Olga; Hu, Chin-Kun

    2015-01-01

    We show that the complex behavior of the tropical cyclone approaching the land can be explained in the frame of two dimensional barotropic model obtained by averaging over the height of the primitive system of equations of the atmosphere dynamics. In particular, this behavior includes a significant track deflection, sudden decay and intensification. In contrast to other models, where first the additional physically reasonable simplifications are made, we deal with special classes of solutions to the full system. This allows us not to lose the symmetries of the model and to catch the complicated features of the full model. Our theoretical considerations are in a good compliance with the experimental data. In particular, our method is able to explain the phenomenon of attraction of the cyclone to the land and interaction of the cyclone with an island.

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

    E-Print Network [OSTI]

    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.

    2009-01-01

    Abstract. Inclusion of fundamental ecological interactions between carbon and nitrogen cycles in the land component of an atmosphere-ocean general circulation model (AOGCM) leads to decreased carbon uptake associated ...

  20. Volume xx (200y), Number z, pp. 115 A Framework for Interactive Hypertexture Modeling

    E-Print Network [OSTI]

    Dischler, Jean-Michel

    , smoke, clouds or fire balls by adding "meso-scale" details to coarsely defined volumetric models. Some

  1. Meso-scale turbulence in living fluids

    E-Print Network [OSTI]

    Wensink, Henricus H; Heidenreich, Sebastian; Drescher, Knut; Goldstein, Raymond E; Löwen, Hartmut; Yeomans, Julia M

    2012-01-01

    Turbulence is ubiquitous, from oceanic currents to small-scale biological and quantum systems. Self-sustained turbulent motion in microbial suspensions presents an intriguing example of collective dynamical behavior amongst the simplest forms of life, and is important for fluid mixing and molecular transport on the microscale. The mathematical characterization of turbulence phenomena in active non-equilibrium fluids proves even more difficult than for conventional liquids or gases. It is not known which features of turbulent phases in living matter are universal or system-specific, or which generalizations of the Navier-Stokes equations are able to describe them adequately. Here, we combine experiments, particle simulations, and continuum theory to identify the statistical properties of self-sustained meso-scale turbulence in active systems. To study how dimensionality and boundary conditions affect collective bacterial dynamics, we measured energy spectra and structure functions in dense Bacillus subtilis su...

  2. Mesoscale Quantization and Self-Organized Stability

    E-Print Network [OSTI]

    Randall D. Peters

    2005-06-16

    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.

  3. Mesoscale Engineering of Nanocomposite Nonlinear Optical Materials

    SciTech Connect (OSTI)

    Afonso, C.N.; Feldman, L.C.; Gonella, F.; Haglund, R.F.; Luepke, G.; Magruder, R.H.; Mazzoldi, P.; Osborne, D.H.; Solis, J.; Zuhr, R.A.

    1999-11-01

    Complex nonlinear optical materials comprising elemental, compound or alloy quantum dots embedded in appropriate dielectric or semiconducting hosts may be suitable for deployment in photonic devices. Ion implantation, ion exchange followed by ion implantation, and pulsed laser deposition have ail been used to synthesize these materials. However, the correlation between the parameters of energetic-beam synthesis and the nonlinear optical properties is still very rudimentary when one starts to ask what is happening at nanoscale dimensions. Systems integration of complex nonlinear optical materials requires that the mesoscale materials science be well understood within the context of device structures. We discuss the effects of beam energy and energy density on quantum-dot size and spatial distribution, thermal conductivity, quantum-dot composition, crystallinity and defects - and, in turn, on the third-order optical susceptibility of the composite material. Examples from recent work in our laboratories are used to illustrate these effects.

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

    SciTech Connect (OSTI)

    Prusa, Joseph

    2012-05-08

    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.

  5. VALDRIFT 1.0: A valley atmospheric dispersion model with deposition

    SciTech Connect (OSTI)

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

    1995-05-01

    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.

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

    SciTech Connect (OSTI)

    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.

    2013-02-07

    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.

  7. Assessment of model estimates of land-atmosphere CO2 exchange across Northern Eurasia

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Rawlins, M. A.; McGuire, A. D.; Kimball, J. S.; Dass, P.; Lawrence, D.; Burke, E.; Chen, X.; Delire, C.; Koven, C.; MacDougall, A.; et al

    2015-07-28

    A warming climate is altering land-atmosphere exchanges of carbon, with a potential for increased vegetation productivity as well as the mobilization of permafrost soil carbon stores. Here we investigate land-atmosphere carbon dioxide (CO2) cycling through analysis of net ecosystem productivity (NEP) and its component fluxes of gross primary productivity (GPP) and ecosystem respiration (ER) and soil carbon residence time, simulated by a set of land surface models (LSMs) over a region spanning the drainage basin of Northern Eurasia. The retrospective simulations cover the period 1960–2009 at 0.5° resolution, which is a scale common among many global carbon and climate modelmore »simulations. Model performance benchmarks were drawn from comparisons against both observed CO2 fluxes derived from site-based eddy covariance measurements as well as regional-scale GPP estimates based on satellite remote-sensing data. The site-based comparisons depict a tendency for overestimates in GPP and ER for several of the models, particularly at the two sites to the south. For several models the spatial pattern in GPP explains less than half the variance in the MODIS MOD17 GPP product. Across the models NEP increases by as little as 0.01 to as much as 0.79 g C m?² yr?², equivalent to 3 to 340 % of the respective model means, over the analysis period. For the multimodel average the increase is 135 % of the mean from the first to last 10 years of record (1960–1969 vs. 2000–2009), with a weakening CO2 sink over the latter decades. Vegetation net primary productivity increased by 8 to 30 % from the first to last 10 years, contributing to soil carbon storage gains. The range in regional mean NEP among the group is twice the multimodel mean, indicative of the uncertainty in CO2 sink strength. The models simulate that inputs to the soil carbon pool exceeded losses, resulting in a net soil carbon gain amid a decrease in residence time. Our analysis points to improvements in model elements controlling vegetation productivity and soil respiration as being needed for reducing uncertainty in land-atmosphere CO2 exchange. These advances will require collection of new field data on vegetation and soil dynamics, the development of benchmarking data sets from measurements and remote-sensing observations, and investments in future model development and intercomparison studies.« less

  8. Researchers are working to develop a mesoscopic theoretical model that captures the physico-chemistry of DNA hybridization.

    E-Print Network [OSTI]

    Bustamante, Fabián E.

    in medical diagnosis. Approach: Meso-scale models that capture the features necessary for predicting physical as the function of atom positions only. Several groups have recently developed meso-scale models to study long

  9. Atomic-Scale Observations Aid Mesoscale Catalyst Design | ornl...

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

    Materials Characterization Atomic-Scale Observations Aid Mesoscale Catalyst Design April 08, 2015 Fig.1. Z-contrast STEM image shows the Mo-V-Te-Ta oxide catalyst. (a) "M1-like"...

  10. Phase Effects on Mesoscale Object X-ray Absorption Images

    SciTech Connect (OSTI)

    Martz, Jr., H E; Aufderheide, M B; Barty, A; Lehman, S K; Kozioziemski, B J; Schneberk, D J

    2004-09-24

    At Lawrence Livermore National Laboratory particular emphasis is being placed on the nondestructive characterization (NDC) of 'mesoscale' objects.[Martz and Albrecht 2003] We define mesoscale objects as objects that have mm extent with {micro}m features. Here we confine our discussions to x-ray imaging methods applicable to mesoscale object characterization. The goal is object recovery algorithms including phase to enable emerging high-spatial resolution x-ray imaging methods to ''see'' inside or image mesoscale-size materials and objects. To be successful our imaging characterization effort must be able to recover the object function to one micrometer or better spatial resolution over a few millimeters field-of-view with very high contrast.

  11. Analysis of azimuthal mode dynamics of mesoscale eddies 

    E-Print Network [OSTI]

    McCalpin, John David

    1984-01-01

    ANALYSIS OF AZIMUTHAL MODE DYNAMICS OF MESOSCALE EDDIES A Thesis by UOHN DAVID MCCALPIN Submitted to the Graduate College of Texas ASM University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE August 1984... Major Subject: Oceanography ANALYSIS OF AZIMUTHAL MODE DYNAMICS OF MESOSCALE EDDIES A Thesis by JOHN DAVID MCCALPIN Approved as to style and content by: rew . as ano (Chairman of Committee) o ert . ei (Member) uy . rancesc &ni (Member) Robert...

  12. 3D Model Atmospheres for Extremely Low-Mass White Dwarfs

    E-Print Network [OSTI]

    Tremblay, P -E; Kilic, M; Ludwig, H -G; Steffen, M; Freytag, B; Hermes, J J

    2015-01-01

    We present an extended grid of mean three-dimensional (3D) spectra for low-mass, pure-hydrogen atmosphere DA white dwarfs (WDs). We use CO5BOLD radiation-hydrodynamics 3D simulations covering Teff = 6000-11,500 K and logg = 5-6.5 (cgs units) to derive analytical functions to convert spectroscopically determined 1D temperatures and surface gravities to 3D atmospheric parameters. Along with the previously published 3D models, the 1D to 3D corrections are now available for essentially all known convective DA WDs (i.e., logg = 5-9). For low-mass WDs, the correction in temperature is relatively small (a few per cent at the most), but the surface gravities measured from the 3D models are lower by as much as 0.35 dex. We revisit the spectroscopic analysis of the extremely low-mass (ELM) WDs, and demonstrate that the 3D models largely resolve the discrepancies seen in the radius and mass measurements for relatively cool ELM WDs in eclipsing double WD and WD + milli-second pulsar binary systems. We also use the 3D cor...

  13. Results of an emergency response atmospheric dispersion model comparison using a state accepted statistical protocol

    SciTech Connect (OSTI)

    Ciolek, J.T. Jr.

    1993-10-01

    The Rocky Flats Plant, located approximately 26 km northwest of downtown Denver, Colorado, has developed an emergency response atmospheric dispersion model for complex terrain applications. Plant personnel would use the model, known as the Terrain-Responsive Atmospheric Code (TRAC) (Hodgin 1985) to project plume impacts and provide off-site protective action recommendations to the State of Colorado should a hazardous material release occur from the facility. The Colorado Department of Health (CDH) entered into an interagency agreement with the Rocky Flats Plant prime contractor, EG&G Rocky Flats, and the US Department of Energy to evaluate TRAC as an acceptable emergency response tool. After exhaustive research of similar evaluation processes from other emergency response and regulatory organizations, the interagency committee devised a formal acceptance process. The process contains an evaluation protocol (Hodgin and Smith 1992), descriptions of responsibilities, an identified experimental data set to use in the evaluation, and judgment criteria for model acceptance. The evaluation protocol is general enough to allow for different implementations. This paper explains one implementation, shows protocol results for a test case, and presents results of a comparison between versions of TRAC with different wind Field codes: a two dimensional mass consistent code called WINDS (Fosberg et al. 1976) that has been extended to three dimensions, and a fully 3 dimensional mass conserving code called NUATMOS (Ross and Smith 1987, Ross et al. 1988).

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

    SciTech Connect (OSTI)

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

    2012-05-08

    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

  15. Boundaries of the Peruvian Oxygen Minimum Zone shaped by coherent mesoscale dynamics

    E-Print Network [OSTI]

    Bettencourt, João H; García, Emilio Hernández; Montes, Ivonne; Sudre, Joël; Dewitte, Boris; Paulmier, Aurélien; Garçon, Véronique

    2015-01-01

    Dissolved oxygen in sea water is a major factor affecting marine habitats and biogeochemical cycles. Oceanic zones with oxygen deficits represent significant portions of the area and volume of the oceans and are thought to be expanding. The Peruvian oxygen minimum zone is one of the most pronounced and lies in a region of strong mesoscale activity in the form of vortices and frontal regions, whose effect in the dynamics of the oxygen minimum zone is largely unknown. Here, we study this issue from a modeling approach and a Lagrangian point of view, using a coupled physical-biogeochemical simulation of the Peruvian oxygen minimum zone and finite-size Lyapunov exponent fields to understand the link between mesoscale dynamics and oxygen variations. Our results show that, at depths between 380 and 600 meters, mesoscale structures have a relevant dual role. First, their mean positions and paths delimit and maintain the oxygen minimum zone boundaries. Second, their high frequency fluctuations entrain oxygen across t...

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

    E-Print Network [OSTI]

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

    2013-08-22

    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.

  17. Fully-coupled engineering and mesoscale simulations of thermal conductivity in UO2 fuel using an implicit multiscale approach

    SciTech Connect (OSTI)

    Michael Tonks; Derek Gaston; Cody Permann; Paul Millett; Glen Hansen; Chris Newman

    2009-08-01

    Reactor fuel performance is sensitive to microstructure changes during irradiation (such as fission gas and pore formation). This study proposes an approach to capture microstructural changes in the fuel by a two-way coupling of a mesoscale phase field irradiation model to an engineering scale, finite element calculation. This work solves the multiphysics equation system at the engineering-scale in a parallel, fully-coupled, fully-implicit manner using a preconditioned Jacobian-free Newton Krylov method (JFNK). A sampling of the temperature at the Gauss points of the coarse scale is passed to a parallel sequence of mesoscale calculations within the JFNK function evaluation phase of the calculation. The mesoscale thermal conductivity is calculated in parallel, and the result is passed back to the engineering-scale calculation. As this algorithm is fully contained within the JFNK function evaluation, the mesoscale calculation is nonlinearly consistent with the engineering-scale calculation. Further, the action of the Jacobian is also consistent, so the composite algorithm provides the strong nonlinear convergence properties of Newton's method. The coupled model using INL's \\bison\\ code demonstrates quadratic nonlinear convergence and good parallel scalability. Initial results predict the formation of large pores in the hotter center of the pellet, but few pores on the outer circumference. Thus, the thermal conductivity is is reduced in the center of the pellet, leading to a higher internal temperature than that in an unirradiated pellet.

  18. Non-LTE model atmosphere analysis of the early ultraviolet spectra of nova OS Andromedae 1986

    E-Print Network [OSTI]

    Greg Schwarz; Peter H. Hauschildt; Sumner Starrfield; Eddie Baron; France Allard; Steve Shore; George Sonneborn

    1996-08-29

    We have analyzed the early optically thick ultraviolet spectra of Nova OS And 1986 using a grid of spherically symmetric, non-LTE, line-blanketed, expanding model atmospheres and synthetic spectra with the following set of parameters: $5,000\\le$ T$_{model}$ $\\le 60,000$K, solar abundances, $\\rho \\propto r^{-3}$, $\\v_{max} = 2000\\kms$, $L=6 \\times 10^{4}\\Lsun$, and a statistical or microturbulent velocity of 50 $\\kms$. We used the synthetic spectra to estimate the model parameters corresponding to the observed {\\it IUE} spectra. The fits to the observations were then iteratively improved by changing the parameters of the model atmospheres, in particular T$_{model}$ and the abundances, to arrive at the best fits to the optically thick pseudo-continuum and the features found in the {\\it IUE} spectra. The {\\it IUE} spectra show two different optically thick subphases. The earliest spectra, taken a few days after maximum optical light, show a pseudo-continuum created by overlapping absorption lines. The later observations, taken approximately 3 weeks after maximum light, show the simultaneous presence of allowed, semi-forbidden, and forbidden lines in the observed spectra. Analysis of these phases indicate that OS And 86 had solar metallicities except for Mg which showed evidence of being underabundant by as much as a factor of 10. We determine a distance of 5.1 kpc to OS And 86 and derive a peak bolometric luminosity of $\\sim$ 5 $\\times$ 10$^4$ L$_{\\odot}$. The computed nova parameters provide insights into the physics of the early outburst and explain the spectra seen by {\\it IUE}. Lastly, we find evidence in the later observations for large non-LTE effects of Fe{\\sc ii} which, when included, lead to much better agreement with the observations.

  19. Planar Fabrication of a Mesoscale Voice Coil Actuator Benjamin Goldberg, Michael Karpelson, Onur Ozcan, and Robert J. Wood

    E-Print Network [OSTI]

    Wood, Robert

    Planar Fabrication of a Mesoscale Voice Coil Actuator Benjamin Goldberg, Michael Karpelson, Onur, USA Abstract-- Mesoscale robots are devices with characteristic dimensions in the centimeter limited. We present a mesoscale voice coil actuator (VCA) with favorable scaling characteristics

  20. C H A P T E R E I G H T E E N Modeling of Growth Factor-Receptor

    E-Print Network [OSTI]

    Popel, Aleksander S.

    -specific receptor binding 472 3. Mesoscale Single-Tissue 3D Models: Simulation of In Vivo Tissue Regions 474 3­receptor interactions at and near the endothelial cell surface; mesoscale single-tissue 3D models can simulate

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

    E-Print Network [OSTI]

    Wu, Xueran; Jacob, Birgit

    2015-01-01

    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...

  2. Towards Direct Simulation of Future Tropical Cyclone Statistics in a High-Resolution Global Atmospheric Model

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Wehner, Michael F.; Bala, G.; Duffy, Phillip; Mirin, Arthur A.; Romano, Raquel

    2010-01-01

    We present a set of high-resolution global atmospheric general circulation model (AGCM) simulations focusing on the model's ability to represent tropical storms and their statistics. We find that the model produces storms of hurricane strength with realistic dynamical features. We also find that tropical storm statistics are reasonable, both globally and in the north Atlantic, when compared to recent observations. The sensitivity of simulated tropical storm statistics to increases in sea surface temperature (SST) is also investigated, revealing that a credible late 21st century SST increase produced increases in simulated tropical storm numbers and intensities in all ocean basins. Whilemore »this paper supports previous high-resolution model and theoretical findings that the frequency of very intense storms will increase in a warmer climate, it differs notably from previous medium and high-resolution model studies that show a global reduction in total tropical storm frequency. However, we are quick to point out that this particular model finding remains speculative due to a lack of radiative forcing changes in our time-slice experiments as well as a focus on the Northern hemisphere tropical storm seasons.« less

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

    SciTech Connect (OSTI)

    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

    2011-10-27

    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.

  4. The Lagrangian particle dispersion model FLEXPART-WRF VERSION 3.1

    SciTech Connect (OSTI)

    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.

    2013-11-01

    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.

  5. Adjusting to policy expectations in climate change modeling : an interdiciplinary study of flux adjustments in coupled atmosphere-ocean general circulation models

    E-Print Network [OSTI]

    Shackley, Simon.; Risbey, James; Stone, Peter H.; Wynne, Brian

    This paper surveys and interprets the attitudes of scientists to the use of flux adjustments in climate projections with coupled Atmosphere Ocean General Circulation Models. The survey is based largely on the responses of ...

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

    SciTech Connect (OSTI)

    Hanna, G; Chang, J.C.; Zhang, J.X.; Bloom, S.G.; Goode, W.D. Jr; Lombardi, D.A.; Yambert, M.W.

    1998-08-01

    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.

  7. Thermospheric tides simulated by the national center for atmospheric research thermosphere-ionosphere general circulation model at equinox

    SciTech Connect (OSTI)

    Fesen, C.G. (Dartmouth College, Hanover, NH (United States)); Roble, R.G.; Ridley, E.C. (National Center for Atmospheric Research, Boulder, CO (United States))

    1993-05-01

    The authors use the National Center for Atmospheric Research (NCAR) thermosphere/ionosphere general circulation model (TIGCM) to model tides and dynamics in the thermosphere. This model incorporates the latest advances in the thermosphere general circulation model. Model results emphasized the 70[degree] W longitude region to overlap a series of incoherent radar scatter installations. Data and the model are available on data bases. The results of this theoretical modeling are compared with available data, and with prediction of more empirical models. In general there is broad agreement within the comparisons.

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

    E-Print Network [OSTI]

    Reif, Rafael

    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

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

    E-Print Network [OSTI]

    V. S. Imshennik; K. V. Manukovskii

    2004-11-16

    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.

  10. A unified parameterization of clouds and turbulence using CLUBB and subcolumns in the Community Atmosphere Model

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Thayer-Calder, K.; Gettelman, A.; Craig, C.; Goldhaber, S.; Bogenschutz, P. A.; Chen, C.-C.; Morrison, H.; Höft, J.; Raut, E.; Griffin, B. M.; et al

    2015-12-01

    Most global climate models parameterize separate cloud types using separate parameterizations. This approach has several disadvantages, including obscure interactions between parameterizations and inaccurate triggering of cumulus parameterizations. Alternatively, a unified cloud parameterization uses one equation set to represent all cloud types. Such cloud types include stratiform liquid and ice cloud, shallow convective cloud, and deep convective cloud. Vital to the success of a unified parameterization is a general interface between clouds and microphysics. One such interface involves drawing Monte Carlo samples of subgrid variability of temperature, water vapor, cloud liquid, and cloud ice, and feeding the sample points intomore »a microphysics scheme. This study evaluates a unified cloud parameterization and a Monte Carlo microphysics interface that has been implemented in the Community Atmosphere Model (CAM) version 5.3. Model computational expense is estimated, and sensitivity to the number of subcolumns is investigated. Results describing the mean climate and tropical variability from global simulations are presented. The new model shows a degradation in precipitation skill but improvements in shortwave cloud forcing, liquid water path, long-wave cloud forcing, precipitable water, and tropical wave simulation.« less

  11. Predicting reptile distributions at the mesoscale: relation to climate and topography

    E-Print Network [OSTI]

    Richner, Heinz

    Predicting reptile distributions at the mesoscale: relation to climate and topography Antoine at a mesoscale level. A more detailed knowledge of these relationships, in combination with maps of the potential

  12. Course: Numerical Simulation in Applied Geophysics. From the Mesoscale to the Macroscale

    E-Print Network [OSTI]

    Santos, Juan

    Course: Numerical Simulation in Applied Geophysics. From the Mesoscale to the Macroscale Professor variations in the fluid and solid matrix properties, fine layering, frac- tures and craks at the mesoscale

  13. DOI: 10.1002/adma.200601882 Spontaneous Formation of Mesoscale Polymer Patterns

    E-Print Network [OSTI]

    Lin, Zhiqun

    DOI: 10.1002/adma.200601882 Spontaneous Formation of Mesoscale Polymer Patterns in an Evaporating of intriguing, ordered structures. Herein, we report on the spontaneous formation of well-or- ganized mesoscale

  14. A distributional approach to the geometry of 2D dislocations at the mesoscale

    E-Print Network [OSTI]

    Lisbon, University of

    A distributional approach to the geometry of 2D dislocations at the mesoscale Part A: General introduce the meso-scale as defined by some average distance between the dislocations. The laws governing

  15. Atomic Force Microscopy of Photosystem II and Its Unit Cell Clustering Quantitatively Delineate the Mesoscale

    E-Print Network [OSTI]

    Geissler, Phillip

    the Mesoscale Variability in Arabidopsis Thylakoids Bibiana Onoa1 , Anna R. Schneider2 , Matthew D. Brooks3 Quantitatively Delineate the Mesoscale Variability in Arabidopsis Thylakoids. PLoS ONE 9(7): e101470. doi:10

  16. Structure of polyamidoamide dendrimers up to limiting generations: A mesoscale description

    E-Print Network [OSTI]

    Goddard III, William A.

    Structure of polyamidoamide dendrimers up to limiting generations: A mesoscale description Prabal K, while reducing the degrees of freedom by tenfold. This mesoscale description has allowed us to study

  17. Zxodes scapularis (Acari:Ixodidae) Deer Tick Mesoscale Populations in Natural Areas: Effects of Deer, Area,

    E-Print Network [OSTI]

    Duffy, David Cameron

    Zxodes scapularis (Acari:Ixodidae) Deer Tick Mesoscale Populations in Natural Areas: Effects al. 1990al) and macroscales (eastern United States [Daniels et al. 19931).We examined the mesoscale

  18. Development of the first nonhydrostatic nested-grid grid-point global atmospheric modeling system on parallel machines

    SciTech Connect (OSTI)

    Kao, C.Y.J.; Langley, D.L.; Reisner, J.M.; Smith, W.S.

    1998-11-01

    This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). Evaluating the importance of global and regional climate response to increasing atmospheric concentrations of greenhouse gases requires a comprehensive global atmospheric modeling system (GAMS) capable of simulations over a wide range of atmospheric circulations, from complex terrain to continental scales, on high-performance computers. Unfortunately, all of the existing global circulation models (GCMs) do not meet this requirements, because they suffer from one or more of the following three shortcomings: (1) use of the hydrostatic approximation, which makes the models potentially ill-posed; (2) lack of a nested-grid (or multi-grid) capability, which makes it difficult to consistently evaluate the regional climate response to the global warming, and (3) spherical spectral (opposed to grid-point finite-difference) representation of model variables, which hinders model performance for parallel machine applications. The end product of the research is a highly modularized, multi-gridded, self-calibratable (for further parameterization development) global modeling system with state-of-the-science physics and chemistry. This system will be suitable for a suite of atmospheric problems: from local circulations to climate, from thunderstorms to global cloud radiative forcing, from urban pollution to global greenhouse trace gases, and from the guiding of field experiments to coupling with ocean models. It will also provide a unique testbed for high-performance computing architecture.

  19. Statistical modelling of discharge behavior of atmospheric pressure dielectric barrier discharge

    SciTech Connect (OSTI)

    Tay, W. H.; Kausik, S. S.; Wong, C. S. Yap, S. L.; Muniandy, S. V.

    2014-11-15

    In this work, stochastic behavior of atmospheric pressure dielectric barrier discharge (DBD) has been investigated. The experiment is performed in a DBD reactor consisting of a pair of stainless steel parallel plate electrodes powered by a 50?Hz ac high voltage source. Current pulse amplitude distributions for different space gaps and the time separation between consecutive current pulses are studied. A probability distribution function is proposed to predict the experimental distribution function for the current pulse amplitudes and the occurrence of the transition regime of the pulse distribution. Breakdown voltage at different positions on the dielectric surface is suggested to be stochastic in nature. The simulated results based on the proposed distribution function agreed well with the experimental results and able to predict the regime of transition voltage. This model would be useful for the understanding of stochastic behaviors of DBD and the design of DBD device for effective operation and applications.

  20. Disaggregation of spatial rainfall fields for hydroloigcal modelling Hydrology and Earth System Sciences, 5(2), 165173 (2001) EGS

    E-Print Network [OSTI]

    Boyer, Edmond

    2001-01-01

    to investigate the evolution of the climate (DOE, 1996) while at the regional scale, mesoscale models are weather. In the case of rainfall forecasting, some combination of the mesoscale forecast and a finer scale advection

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

    SciTech Connect (OSTI)

    Hoffman, Forrest M; Randerson, Jim; Thornton, Peter E; Mahowald, Natalie; Bonan, Gordon; Running, Steven; Fung, Inez

    2009-01-01

    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.

  2. Global energy and water balance: Characteristics from finite-volume atmospheric model of the IAP/LASG (FAMIL1)

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Zhou, Linjiong; Bao, Qing; Liu, Yimin; Wu, Guoxiong; Wang, Wei-Chyung; Wang, Xiaocong; He, Bian; Yu, Haiyang; Li, Jiandong

    2015-03-01

    This paper documents version 1 of the Finite-volume Atmospheric Model of the IAP/LASG (FAMIL1), which has a flexible horizontal resolution up to a quarter of 1°. The model, currently running on the ‘‘Tianhe 1A’’ supercomputer, is the atmospheric component of the third-generation Flexible Global Ocean-Atmosphere-Land climate System model (FGOALS3) which will participate in the Coupled Model Intercomparison Project Phase 6 (CMIP6). In addition to describing the dynamical core and physical parameterizations of FAMIL1, this paper describes the simulated characteristics of energy and water balances and compares them with observational/reanalysis data. The comparisons indicate that the model simulates well the seasonalmore »and geographical distributions of radiative fluxes at the top of the atmosphere and at the surface, as well as the surface latent and sensible heat fluxes. A major weakness in the energy balance is identified in the regions where extensive and persistent marine stratocumulus is present. Analysis of the global water balance also indicates realistic seasonal and geographical distributions with the global annual mean of evaporation minus precipitation being approximately 10?? mm d?¹. We also examine the connections between the global energy and water balance and discuss the possible link between the two within the context of the findings from the reanalysis data. Finally, the model biases as well as possible solutions are discussed.« less

  3. A unified parameterization of clouds and turbulence using CLUBB and subcolumns in the Community Atmosphere Model

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Thayer-Calder, K.; Gettelman, A.; Craig, C.; Goldhaber, S.; Bogenschutz, P. A.; Chen, C.-C.; Morrison, H.; Höft, J.; Raut, E.; Griffin, B. M.; et al

    2015-06-30

    Most global climate models parameterize separate cloud types using separate parameterizations. This approach has several disadvantages, including obscure interactions between parameterizations and inaccurate triggering of cumulus parameterizations. Alternatively, a unified cloud parameterization uses one equation set to represent all cloud types. Such cloud types include stratiform liquid and ice cloud, shallow convective cloud, and deep convective cloud. Vital to the success of a unified parameterization is a general interface between clouds and microphysics. One such interface involves drawing Monte Carlo samples of subgrid variability of temperature, water vapor, cloud liquid, and cloud ice, and feeding the sample points into amore »microphysics scheme. This study evaluates a unified cloud parameterization and a Monte Carlo microphysics interface that has been implemented in the Community Atmosphere Model (CAM) version 5.3. Results describing the mean climate and tropical variability from global simulations are presented. The new model shows a degradation in precipitation skill but improvements in short-wave cloud forcing, liquid water path, long-wave cloud forcing, precipitable water, and tropical wave simulation. Also presented are estimations of computational expense and investigation of sensitivity to number of subcolumns.« less

  4. A unified parameterization of clouds and turbulence using CLUBB and subcolumns in the Community Atmosphere Model

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Thayer-Calder, K.; Gettelman, A.; Craig, C.; Goldhaber, S.; Bogenschutz, P. A.; Chen, C.-C.; Morrison, H.; Höft, J.; Raut, E.; Griffin, B. M.; et al

    2015-06-30

    Most global climate models parameterize separate cloud types using separate parameterizations. This approach has several disadvantages, including obscure interactions between parameterizations and inaccurate triggering of cumulus parameterizations. Alternatively, a unified cloud parameterization uses one equation set to represent all cloud types. Such cloud types include stratiform liquid and ice cloud, shallow convective cloud, and deep convective cloud. Vital to the success of a unified parameterization is a general interface between clouds and microphysics. One such interface involves drawing Monte Carlo samples of subgrid variability of temperature, water vapor, cloud liquid, and cloud ice, and feeding the sample points intomore »a microphysics scheme. This study evaluates a unified cloud parameterization and a Monte Carlo microphysics interface that has been implemented in the Community Atmosphere Model (CAM) version 5.3. Results describing the mean climate and tropical variability from global simulations are presented. The new model shows a degradation in precipitation skill but improvements in short-wave cloud forcing, liquid water path, long-wave cloud forcing, precipitable water, and tropical wave simulation. Also presented are estimations of computational expense and investigation of sensitivity to number of subcolumns.« less

  5. Mesoscale symmetries explain dynamical equivalence of food webs

    E-Print Network [OSTI]

    Aufderheide, Helge; Gross, Thilo

    2012-01-01

    A present challenge in complex systems is to identify mesoscale structures that have distinct dynamical implications. In this paper we present a detailed investigation of a previously observed dynamical equivalence of certian ecological food webs. We show that this equivalence is rooted in mesoscale symmetries that exist in these webs. Certain eigenvectors of the Jacobian describing dynamical modes of the system, such as specific instabilities or responses to perturbations, localize on these symmetric motifs. On the one hand this means that by removing a symmetry from the network one obtains a system which has identical dynamics except for the removal of the localized mode. This explains the previously observed equivalence. On the other hand it means that we can identify dynamical modes that only depend on the symmetric motif. Symmetric structures thus provide an example for mesoscale network motifs having distinct and exact implications for the dynamics.

  6. Copyright (to be inserted by the publisher ) Mesoscale simulation of grain growth

    E-Print Network [OSTI]

    Citation & Copyright (to be inserted by the publisher ) Mesoscale simulation of grain growth David, USA Keywords: grain growth, mesoscale, algorithm, dissipative system, Mullins Equation, Herring. Here we exhibit a consistent variational approach to the mesoscale simulation of large systems of grain

  7. Real-Time Forecasting for the Antarctic: An Evaluation of the Antarctic Mesoscale Prediction System (AMPS)*

    E-Print Network [OSTI]

    Howat, Ian M.

    Real-Time Forecasting for the Antarctic: An Evaluation of the Antarctic Mesoscale Prediction System. MANNING AND JORDAN G. POWERS Mesoscale and Microscale Meteorology Division, National Center.S. Antarctic Program's field operations, the Antarctic Mesoscale Prediction System (AMPS) was implemented in Oc

  8. Practical and Intrinsic Predictability of Severe and Convective Weather at the Mesoscales

    E-Print Network [OSTI]

    Practical and Intrinsic Predictability of Severe and Convective Weather at the Mesoscales at the mesoscales using convection-permitting ensemble simulations of a squall line and bow echo event during the Bow Echo and Mesoscale Convective Vortex (MCV) Experiment (BAMEX) on 9­10 June 2003. Although most

  9. Mixed Layer Cooling in Mesoscale Oceanic Eddies during Hurricanes Katrina and Rita

    E-Print Network [OSTI]

    Miami, University of

    Mixed Layer Cooling in Mesoscale Oceanic Eddies during Hurricanes Katrina and Rita BENJAMIN JAIMES. Introduction Isotherm topography and energetic geostrophic flow in mesoscale oceanic features in the Gulf. 2000; Shay et al. 2000). The dependence of hurricane-induced OML cooling on the presence of mesoscale

  10. Charge rearrangement by sprites over a north Texas mesoscale convective system

    E-Print Network [OSTI]

    Cummer, Steven A.

    Charge rearrangement by sprites over a north Texas mesoscale convective system William W. Hager,1 is analyzed for a mesoscale convective system (MCS) situated in north Texas and east New Mexico on 15 July. Lapierre (2012), Charge rearrangement by sprites over a north Texas mesoscale convective system, J. Geophys

  11. ATM678, Mesoscale Dynamics, Spring 2014 Class time: TR 11:30am to 1pm

    E-Print Network [OSTI]

    Moelders, Nicole

    ATM678, Mesoscale Dynamics, Spring 2014 Class time: TR 11:30am to 1pm Classroom: Elvy auditorium, Akasofu 319 Course Description: The class provides a comprehensive explanation of mesoscale air motions ­ their phenology, basic physics and mechanisms, why they build and how mesoscale motions interact with the micro

  12. Near-Inertial Wave Wake of Hurricanes Katrina and Rita over Mesoscale Oceanic Eddies

    E-Print Network [OSTI]

    Miami, University of

    Near-Inertial Wave Wake of Hurricanes Katrina and Rita over Mesoscale Oceanic Eddies BENJAMIN; Jaimes and Shay 2009, hereafter JS09). These robust mesoscale oceanic features are present at any time (Jaimes 2009). This mesoscale ocean variability imposed important dynamical constraints on the OML

  13. Asymmetric Catalysis at the Mesoscale: Gold Nanoclusters Embedded in Chiral Self-Assembled Monolayer as Heterogeneous

    E-Print Network [OSTI]

    Asymmetric Catalysis at the Mesoscale: Gold Nanoclusters Embedded in Chiral Self of the catalytically active metallic sites and the surrounding chiral SAM for the formation of a mesoscale the catalytically active site from the nanoscale to the mesoscale, which implies a principle of operating systems

  14. Analysis of a mesoscale infiltration and water seepage test in unsaturated fractured rock: Spatial variabilities

    E-Print Network [OSTI]

    Zhou, Quanlin

    Analysis of a mesoscale infiltration and water seepage test in unsaturated fractured rock: Spatial 2006 Abstract A mesoscale (21 m in flow distance) infiltration and seepage test was recently conducted flow in fractured rock at mesoscale or a larger scale is not necessarily conditional explicitly

  15. Mesoscale eddies northeast of the Hawaiian archipelago from satellite altimeter observations

    E-Print Network [OSTI]

    Qiu, Bo

    Mesoscale eddies northeast of the Hawaiian archipelago from satellite altimeter observations; published 16 March 2010. [1] Enhanced mesoscale eddy activity northeast of the Hawaiian archipelago by 5° longitude subregions revealed the dominant mesoscale periods ranging from 90 days near 18°N

  16. On the role of mesoscale eddies in the ventilation of Antarctic intermediate water

    E-Print Network [OSTI]

    Fischlin, Andreas

    On the role of mesoscale eddies in the ventilation of Antarctic intermediate water Zouhair Lachkar Mesoscale eddies CFC-11 Ventilation Southern Ocean a b s t r a c t The spatial distribution of Antarctic and ventilation are substantially affected by mesoscale eddies. To diagnose the role of eddies, we made global CFC

  17. Small and mesoscale properties of a substorm onset auroral arc H. U. Frey,1

    E-Print Network [OSTI]

    California at Berkeley, University of

    Small and mesoscale properties of a substorm onset auroral arc H. U. Frey,1 O. Amm,2 C. C. Chaston; revised 22 June 2010; accepted 28 June 2010; published 7 October 2010. [1] We present small and mesoscale. Good agreement could be reached for the mesoscale arc properties. A qualitative analysis

  18. Seasonal Mesoscale and Submesoscale Eddy Variability along the North Pacific Subtropical Countercurrent

    E-Print Network [OSTI]

    Qiu, Bo

    Seasonal Mesoscale and Submesoscale Eddy Variability along the North Pacific Subtropical abundant in mesoscale eddies, but also exhibits prominent submesoscale eddy features. Output from a 1 the seasonal STCC variability in the mesoscale versus submesoscale ranges. Resolving the eddy scales of .150 km

  19. Deriving Mesoscale Surface Current Fields from Multi-Sensor Satellite Data , B. Seppke b

    E-Print Network [OSTI]

    Hamburg,.Universität

    Deriving Mesoscale Surface Current Fields from Multi-Sensor Satellite Data M. Gade a , B. Seppke b of mesoscale surface currents in the southestern Baltic Sea (Southern Baltic Proper). Marine surface films of the two-dimensional data sets may therefore allow for the calculation of mesoscale ocean current fields

  20. Sensitivity of Mesoscale Surface Dynamics to Surface Soil and Vegetation Contrasts over the Carolina Sandhills

    E-Print Network [OSTI]

    Raman, Sethu

    Sensitivity of Mesoscale Surface Dynamics to Surface Soil and Vegetation Contrasts over in mesoscale summertime precipitation over this region. Numerical simulations are analyzed to investigate the relationships between mesoscale surface dynamics and the transition from clay to sandy soils over this region

  1. Global Observations of Nonlinear Mesoscale Eddies Dudley B. Chelton, Michael G. Schlax and Roger M. Samelson

    E-Print Network [OSTI]

    Kurapov, Alexander

    Global Observations of Nonlinear Mesoscale Eddies Dudley B. Chelton, Michael G. Schlax and Roger M mesoscale variability in the global ocean. The prevalence of eddy-like structures with scales of O(100 km mesoscale features based on their SSH signatures yields 35,891 eddies with lifetimes 16 weeks. These long

  2. Mesoscale and clusters of synchrony in networks of bursting neurons Igor Belykh1

    E-Print Network [OSTI]

    Belykh, Igor

    Mesoscale and clusters of synchrony in networks of bursting neurons Igor Belykh1 and Martin Hasler2 with relatively large clusters, leading potentially to cluster synchronization at the mesoscale network level. We represent the microscale level, cooperative rhythms of neuronal subpopulations define the mesoscale level

  3. Numerical Simulation of Mesoscale Circulations in a Region of Contrasting Soil Types

    E-Print Network [OSTI]

    Raman, Sethu

    Numerical Simulation of Mesoscale Circulations in a Region of Contrasting Soil Types SETHU RAMAN,1 AARON SIMS,1,2 ROBB ELLIS,1 and RYAN BOYLES 1 Abstract--Mesoscale processes that form due to changes on mesoscale processes are examined. Climatological analyses indicate increased convective precipitation

  4. ach year across the US, mesoscale weather events--flash floods, tornadoes, hail,

    E-Print Network [OSTI]

    Plale, Beth

    E ach year across the US, mesoscale weather events--flash floods, tornadoes, hail, strong winds of mesoscale weather research; its disparate, high-volume data sets and streams; or the tremendous urgent need for a comprehensive national cyberinfrastructure in mesoscale meteorology--particularly one

  5. Mesoscale simulations of gravity waves during the 20082009 major stratospheric sudden warming

    E-Print Network [OSTI]

    Limpasuvan, Varavut

    Mesoscale simulations of gravity waves during the 2008­2009 major stratospheric sudden warming September 2011. [1] A series of 24 h mesoscale simulations (of 10 km horizontal and 400 m vertical. Yamashita (2011), Mesoscale simulations of gravity waves during the 2008­2009 major stratospheric sudden

  6. PHYSICAL REVIEW A 83, 043827 (2011) Quantum fluctuations and saturable absorption in mesoscale lasers

    E-Print Network [OSTI]

    Levi, Anthony F. J.

    2011-01-01

    PHYSICAL REVIEW A 83, 043827 (2011) Quantum fluctuations and saturable absorption in mesoscale in mesoscale lasers. The time evolution of the density matrix is obtained from numerical integration and field behavior of mesoscale lasers. Using only semiclassical master equations and specific device parameters

  7. Influence of mesoscale eddies on ichthyoplankton assemblages in the Gulf of Alaska

    E-Print Network [OSTI]

    Influence of mesoscale eddies on ichthyoplankton assemblages in the Gulf of Alaska ELIZABETH ATWOOD 98115, USA ABSTRACT Mesoscale eddies (100­200 km in diameter) propa- gating along the shelf in these eddies was examined using data from a cruise in 2005 that sampled three eastern Gulf of Alaska mesoscale

  8. Melting and crystallization in Ni nanoclusters: The mesoscale regime Yue Qi and Tahir C agin

    E-Print Network [OSTI]

    Goddard III, William A.

    Melting and crystallization in Ni nanoclusters: The mesoscale regime Yue Qi and Tahir C¸ agin to a mesoscale nanocrystal regime well-defined bulk and surface properties above 750 atoms 2.7 nm . We find that the mesoscale nanocrystals melt via surface processes, leading to Tm,N Tm,bulk N 1/3 , dropping from Tm

  9. THE ROLE OF CLOUD MICROPHYSICS PARAMETERIZATION IN THE SIMULATION OF MESOSCALE CONVECTIVE SYSTEMS AND ANVIL

    E-Print Network [OSTI]

    THE ROLE OF CLOUD MICROPHYSICS PARAMETERIZATION IN THE SIMULATION OF MESOSCALE CONVECTIVE SYSTEMS in the Simulation of Mesoscale Convective Systems and Anvil Clouds in the Tropical Western Pacific K. Van Weverberg1 cloud microphysics in the simulation of mesoscale convective systems (MCSs) in the tropical western

  10. PROBCAST: A Web-Based Portal to Mesoscale Probabilistic Forecasts Clifford Mass1

    E-Print Network [OSTI]

    Mass, Clifford F.

    1 PROBCAST: A Web-Based Portal to Mesoscale Probabilistic Forecasts Clifford Mass1 , Susan Joslyn over the Pacific Northwest. PROBCAST products are derived from the output of a mesoscale ensemble-processing of mesoscale, short-range ensembles. The NAS report also noted current deficiencies in the communication

  11. A Climatology of Midlatitude Mesoscale Convective Vortices in the Rapid Update Cycle

    E-Print Network [OSTI]

    Johnson, Richard H.

    A Climatology of Midlatitude Mesoscale Convective Vortices in the Rapid Update Cycle ERIC P. JAMES of mesoscale convective vortices (MCVs) occurring in the state of Oklahoma during the late spring and summer, true MCVs represent only about 20% of the mesoscale relative vorticity maxima detected by the algorithm

  12. Author , Short title EFFECTS OF MESOSCALE TEXTURE ON APPARENT SURFACE GLOSS

    E-Print Network [OSTI]

    Ferwerda, James A.

    Author , Short title 1 EFFECTS OF MESOSCALE TEXTURE ON APPARENT SURFACE GLOSS James A. Ferwerda to it. We first measure both the microscale reflectance properties and mesoscale texture of flat, latex these images as stimuli in perceptual experiments to systematically study how surface mesoscale properties

  13. Patterns of Precipitation and Mesolow Evolution in Midlatitude Mesoscale Convective Vortices

    E-Print Network [OSTI]

    Johnson, Richard H.

    Patterns of Precipitation and Mesolow Evolution in Midlatitude Mesoscale Convective Vortices ERIC P manifestations of mesoscale convective vortices (MCVs) that traversed Oklahoma during the periods May­August 2002 Profiler Network data. Forty-five MCVs that developed from mesoscale convective systems (MCSs) have been

  14. Development of a Piezoelectrically-Actuated Mesoscale Robot Quadruped Michael Goldfarb, Michael Gogola, Gregory Fischer

    E-Print Network [OSTI]

    Simaan, Nabil

    Development of a Piezoelectrically-Actuated Mesoscale Robot Quadruped Michael Goldfarb, Michael approach that offers a high locomotive efficiency, and is therefore well suited to mesoscale robot design actuated mesoscale robot quadruped. The design described utilizes a lightly damped skeletal structure

  15. Persistence of iron limitation in the western subarctic Pacific SEEDS II mesoscale fertilization experiment

    E-Print Network [OSTI]

    Cochlan, William P.

    Persistence of iron limitation in the western subarctic Pacific SEEDS II mesoscale fertilization t The cumulative evidence from more than a dozen mesoscale iron-enrichment studies in high nitrate low chlorophyll diatoms, vary greatly among these mesoscale experiments even though similar amounts of iron were added

  16. Transient luminous events above two mesoscale convective systems: Charge moment change analysis

    E-Print Network [OSTI]

    Cummer, Steven A.

    Transient luminous events above two mesoscale convective systems: Charge moment change analysis. A. Rutledge, and D. R. MacGorman (2011), Transient luminous events above two mesoscale convective in the stratiform region of a mesoscale convective system (MCS) [Houze et al., 1990] by energetic positive CG (+CG

  17. Deep-Sea Research I 53 (2006) 321332 Effects of mesoscale phytoplankton variability on the copepods

    E-Print Network [OSTI]

    Thomas, Andrew

    2006-01-01

    Deep-Sea Research I 53 (2006) 321­332 Effects of mesoscale phytoplankton variability encompassing the spring phytoplankton bloom. Satellite imagery indicates high mesoscale variability hypothesized that phytoplankton ingestion by N. flemingeri and N. plumchrus would vary in response to mesoscale

  18. Studies on non-premixed flame streets in a mesoscale channel

    E-Print Network [OSTI]

    Ju, Yiguang

    Studies on non-premixed flame streets in a mesoscale channel Bo Xu *, Yiguang Ju Department of channel width, wall temperature, and flow rate on the dynamics of non-premix flames in a mesoscale The Combustion Institute. Published by Elsevier Inc. All rights reserved. Keywords: Mesoscale combustion; Non

  19. Segmentation of mesoscale ocean surface dynamics using satellite SST and SSH observations

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 Segmentation of mesoscale ocean surface dynamics using satellite SST and SSH observations Pierre about ocean circulation, espe- cially mesoscale ocean dynamics which may involve strong spatio- temporal to which mesoscale ocean dynamics may be decomposed into a mixture of dynamical modes, characterized

  20. Mesoscale Simulation of Grain David Kinderlehrer, Jeehyun Lee, Irene Livshits and Shlomo Ta'asan

    E-Print Network [OSTI]

    Mesoscale Simulation of Grain Growth David Kinderlehrer, Jeehyun Lee, Irene Livshits and Shlomo Ta'asan WILEY-VCH Verlag Berlin GmbH September 4, 2003 #12;2 0.1 Introduction The mesoscale simulation of grain of the statistics it provides, we are led to the companion issue of coarse graining in mesoscale simulations. We

  1. Mesoscale energetics and ows induced by sea-land and mountain-valley contrasts

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Mesoscale energetics and ¯ows induced by sea-land and mountain-valley contrasts S. Federico1 , G. A in determining the development of thermally forced mesoscale circula- tions (TFMCs) over a mountainous peninsula dynamics (climatology; mesoscale meteorology) 1 Introduction In the early hours of the morning the sun

  2. Mesoscale transport properties induced by near critical resistive pressure-gradient-driven turbulence in toroidal geometry

    E-Print Network [OSTI]

    Martín-Solís, José Ramón

    Mesoscale transport properties induced by near critical resistive pressure diffusive equation for mesoscale tracer-particle transport. The indices of the fractional derivates a mesoscale regime. That is, for time scales above the fluctuation scales reaching to the trans- port scales

  3. Draft Chapter from Mesoscale Dynamic Meteorology By Prof. Yu-lang Lin, North Carolina State University

    E-Print Network [OSTI]

    Droegemeier, Kelvin K.

    1 Draft Chapter from Mesoscale Dynamic Meteorology By Prof. Yu-lang Lin, North Carolina State University Chapter 1 Overview 1.1 Introduction The so-called mesometeorology or mesoscale meteorology as mesoscale phenomena by others (e.g. Orlanski 1975; Thunis and Bornstein 1996). Therefore, a more precise

  4. Mesoscale eddies in the northeastern Pacific tropical-subtropical transition zone: Statistical characterization from satellite altimetry

    E-Print Network [OSTI]

    Mesoscale eddies in the northeastern Pacific tropical-subtropical transition zone: Statistical February 2012; revised 24 August 2012; accepted 6 September 2012; published 24 October 2012. [1] Mesoscale cycle. Although mesoscale eddies in these areas have been previously reported, this study provides

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

    E-Print Network [OSTI]

    Prentiss, Mara

    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-assembly from the molecular to the mesoscale, (ii) the demonstration of a system in which small objects can

  6. Mesoscale Simulation of Tropical Cyclones in the South Pacific: Climatology and Interannual Variability

    E-Print Network [OSTI]

    Mesoscale Simulation of Tropical Cyclones in the South Pacific: Climatology and Interannual is shown to reproduce a wide range of mesoscale convective systems. Tropical cyclones grow from the most related to mesoscale in- teractions, which also affect TC tracks and the resulting occurrence. 1

  7. Mesoscale distribution of zooplankton biomass in the northeast Atlantic Ocean determined with an Optical Plankton Counter

    E-Print Network [OSTI]

    Mesoscale distribution of zooplankton biomass in the northeast Atlantic Ocean determined Available online 2 June 2009 Keywords: Zooplankton Biomass Size distribution Mesoscale eddies Optical plankton counter Pelagic environment Northeast Atlantic Ocean a b s t r a c t We examined the mesoscale

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

    E-Print Network [OSTI]

    2008-01-01

    1960 through 2001, Carbon Dioxide Inf. Anal. Cent. , OakAtmospheric and oceanic carbon dioxide models, Science, 282,Data on Global Change, Carbon Dioxide Inf. Anal. Cent. , Oak

  9. Eddy heat fluxes at Drake Passage due to mesoscale motions 

    E-Print Network [OSTI]

    Rojas Recabal, Ricardo Luis

    1982-01-01

    EDDY HEAT FLUKES AT DRAKE PASSAGE DUE TO MESOSCALE MOTIONS A Thesis by RICARDO LUIS ROJAS RECABAL Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE May... 1982 Major Subject: Oceanography EDDY HEAT FLUXES AT DRAKE PASSAGE DUE TO MESOSCALE NOTIONS A Thesis by RICARDO LUIS ROJAS RECABAL Approved as to style and content by: was )W-~ Member em er May 1982 ABSTRACT Eddy Heat Fluxes at Drake Passage...

  10. 3D modeling of GJ1214b's atmosphere: vertical mixing driven by an anti-Hadley circulation

    E-Print Network [OSTI]

    Charnay, Benjamin; Leconte, Jérémy

    2015-01-01

    GJ1214b is a warm sub-Neptune transiting in front of a nearby M dwarf star. Recent observations indicate the presence of high and thick clouds or haze whose presence requires strong atmospheric mixing. In order to understand the transport and distribution of such clouds/haze, we study the atmospheric circulation and the vertical mixing of GJ1214b with a 3D General Circulation Model for cloud-free hydrogen-dominated atmospheres (metallicity of 1, 10 and 100 times the solar value) and for a water-dominated atmosphere. We analyze the effect of the atmospheric metallicity on the thermal structure and zonal winds. We also analyze the zonal mean meridional circulation and show that it corresponds to an anti-Hadley circulation in most of the atmosphere with upwelling at mid-latitude and downwelling at the equator in average. This circulation must be present on a large range of synchronously rotating exoplanets with strong impact on cloud formation and distribution. Using simple tracers, we show that vertical winds o...

  11. Model atmospheres and X-ray spectra of iron-rich bursting neutron stars. II. Iron rich Comptonized Spectra

    E-Print Network [OSTI]

    A. Majczyna; J. Madej; P. C. Joss; A. Rozanska

    2004-12-28

    This paper presents the set of plane-parallel model atmosphere equations for a very hot neutron star (X-ray burst source). The model equations assume both hydrostatic and radiative equilibrium, and the equation of state of an ideal gas in local thermodynamic equilibrium (LTE). The equation of radiative transfer includes terms describing Compton scattering of photons on free electrons in fully relativistic thermal motion, for photon energies approaching m_e *c^2. Model equations take into account many bound-free and free-free energy-dependent opacities of hydrogen, helium, and the iron ions, and also a dozen bound-bound opacities for the highest ions of iron. We solve model equations by partial linearisation and the technique of variable Eddington factors. Large grid of H-He-Fe model atmospheres of X-ray burst sources has been computed for 10^7 neutron stars from observational data.

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

    E-Print Network [OSTI]

    Johnson, Richard H.

    October 1986 R. H. Johnson 721 Lower-Tropospheric Warming and Drying in Tropical Mesoscale components of tropical mesoscale convective systems. It is found that while the apparent heat source Q1 of mesoscale downdrafts within the mesoscale convective systems. The warming and drying at low levels

  13. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Calibrated Probabilistic Mesoscale Weather Field Forecasting: The Geostatist...

    E-Print Network [OSTI]

    Raftery, Adrian

    permission. Calibrated Probabilistic Mesoscale Weather Field Forecasting: The Geostatist... Yulia Gel; Adrian

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

    SciTech Connect (OSTI)

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

    2012-04-09

    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.

  15. 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)

    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

    2013-11-08

    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.

  16. Tracking Atmospheric Ducts Using Radar Clutter: II. Surface-based Duct Tracking Using Multiple Model

    E-Print Network [OSTI]

    Gerstoft, Peter

    Tracking Atmospheric Ducts Using Radar Clutter: II. Surface-based Duct Tracking Using Multiple variability in tracking surface-based ducts in marine and coastal environments. The method tracks of the problem and evaporation duct tracking has been introduced in [1]. In previous studies, atmospheric

  17. Characterization of Caribbean Meso-Scale Eddies Jose M. Lopez

    E-Print Network [OSTI]

    Gilbes, Fernando

    Characterization of Caribbean Meso-Scale Eddies Jose M. Lopez Department of Marine Sciences, P will be subjected to 3-D spectrofluorometry and scanning spectrophotometry for CDOM characterization (J. Corredor, J. Morell). Current structure across fronts and eddies will be characterized by means of ship-lowered ADCP

  18. Numerical Simulation in Applied Geophysics. From the Mesoscale to the

    E-Print Network [OSTI]

    Santos, Juan

    Seismic wave propagation is a common technique used in hydrocarbon exploration geophysics, mining's crust and induce attenuation, dispersion and anisotropy of the seismic waves observed at the macroscale process. Numerical Simulation in Applied Geophysics. From the Mesoscale to the Macroscale ­ p. #12

  19. 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

  20. Mesoscale simulations of surfactant dissolution and mesophase formation

    E-Print Network [OSTI]

    P. Prinsen; P. B. Warren; M. A. J. Michels

    2002-04-22

    The evolution of the contact zone between pure surfactant and solvent has been studied by mesoscale simulation. It is found that mesophase formation becomes diffusion controlled and follows the equilibrium phase diagram adiabatically almost as soon as individual mesophases can be identified, corresponding to times in real systems of order 10 microseconds.

  1. Precipitation hydrometeor type relative to the mesoscale airflow in mature

    E-Print Network [OSTI]

    Houze Jr., Robert A.

    Precipitation hydrometeor type relative to the mesoscale airflow in mature oceanic deep convection systems whose contiguous precipitation spans at least ~100 km in one direction [Houze 2004]. These cloud systems are composed of small, intensely precipitating convective regions and expansive stratiform regions

  2. A nonsteady one-dimensional theoretical model of Mars' neutral atmospheric composition between 30 and 200 km

    SciTech Connect (OSTI)

    Rodrigo, R.; Garcia-Alvarez, E.; Lopez-Gonzalez, M.J.; Lopez-Moreno, J.J. (Instituto de Astrofisica de Andalucia, Granada (Spain))

    1990-08-30

    There has been a big advance in the knowledge of the composition of the atmosphere of the planet Mars since its exploration by different missions in the 1970s, and this will be deeply increased in the following years as the upcoming programs to Mars develop. In this context, the authors have elaborated a model of the Mars' neutral atmosphere including the following compounds: O({sup 3}P), O({sup 1}D), O{sub 2}, O{sub 3}, H, H{sub 2}, OH, H{sub 2}O, HO{sub 2}, H{sub 2}O{sub 2}, CO, and CO{sub 2}, between 30 and 200 km of altitude. The model is carried out for middle latitudes in equinox conditions and with moderate solar activity and provides the day-to-night evolution of the atmosphere. The scarcity of observations corresponding to the nightside of the planet has made it necessary to calculate the atmospheric temperature profile based on the available observations and on theoretical estimations. The model includes a detailed treatment of both the photochemical and the dynamical processes. In this sense, the most recent values of the reaction rates and photodissociation cross sections have been used, and a new height profile of the eddy diffusion coefficient has been computed which is able to explain the vertical distribution of carbon monoxide. The concentration profiles obtained show, in general, a very good agreement with the available experimental measurements.

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

    SciTech Connect (OSTI)

    Keene, William C.; Long, Michael S.

    2013-05-20

    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 Chemistryâ??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 Earthâ??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.

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

    SciTech Connect (OSTI)

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

    2014-11-27

    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.

  5. Atmospheric Environment ] (

    E-Print Network [OSTI]

    Raman, Sethu

    that the influence of the urban region on wind patterns and atmospheric stability could be studied. HeightAtmospheric Environment ] (

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

    SciTech Connect (OSTI)

    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

    2009-10-01

    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.

  7. Modeling of the optical properties of nonspherical particles in the atmosphere 

    E-Print Network [OSTI]

    Chen, Guang

    2009-05-15

    The single scattering properties of atmospheric particles are fundamental to radiative simulations and remote sensing applications. In this study, an efficient technique, namely, the pseudo-spectral time-domain (PSTD) ...

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

    E-Print Network [OSTI]

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

    2008-03-25

    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.

  9. A global view of gravity waves in the Martian atmosphere inferred from a high-resolution general circulation model

    E-Print Network [OSTI]

    Kuroda, Takeshi; Yi?it, Erdal; Hartogh, Paul

    2015-01-01

    Global characteristics of the small-scale gravity wave (GW) field in the Martian atmosphere obtained from a high-resolution general circulation model (GCM) are presented for the first time. The simulated GW-induced temperature variances are in a good agreement with available radio occultation data in the lower atmosphere between 10 and 30 km. The model reveals a latitudinal asymmetry with stronger wave generation in the winter hemisphere, and two distinctive sources of GWs: mountainous regions and the meandering winter polar jet. Orographic GWs are filtered while propagating upward, and the mesosphere is primarily dominated by harmonics with faster horizontal phase velocities. Wave fluxes are directed mainly against the local wind. GW dissipation in the upper mesosphere generates body forces of tens of m~s$^{-1}$~sol$^{-1}$, which tend to close the simulated jets. The results represent a realistic surrogate for missing observations, which can be used for constraining GW parameterizations and validating GCM si...

  10. Atmospheric Properties from the 2006 Niamey Deployment and Climate Simulation with a Geodesic Grid Coupled Climate Model

    SciTech Connect (OSTI)

    Jensen, M; Johnson, K; Mather, J; Randall, D

    2008-03-01

    In 2008, the Atmospheric Radiation Measurement (ARM) Program and the Climate Change Prediction Program (CCPP) have been asked to produce joint science metrics. For CCPP, the metrics will deal with a decade-long control simulation using geodesic grid-coupled climate model. For ARM, the metrics will deal with observations associated with the 2006 deployment of the ARM Mobile Facility (AMF) to Niamey, Niger. Specifically, ARM has been asked to deliver data products for Niamey that describe cloud, aerosol, and dust properties.

  11. Mesoscale simulation of shocked poly-(4-methyl-1-pentene) (PMP) foams.

    SciTech Connect (OSTI)

    Schroen, Diana Grace; Flicker, Dawn G.; Haill, Thomas A.; Root, Seth; Mattsson, Thomas Kjell Rene

    2011-06-01

    Hydrocarbon foams are commonly used in HEDP experiments, and are subject to shock compression from tens to hundreds of GPa. Modeling foams is challenging due to the heterogeneous character of the foam. A quantitative understanding of foams under strong dynamic compression is sought. We use Sandia's ALEGRA-MHD code to simulate 3D mesoscale models of pure poly(4-methyl-1-petene) (PMP) foams. We employ two models of the initial polymer-void structure of the foam and analyze the statistical properties of the initial and shocked states. We compare the simulations to multi-Mbar shock experiments at various initial foam densities and flyer impact velocities. Scatter in the experimental data may be a consequence of the initial foam inhomogeneity. We compare the statistical properties the simulations with the scatter in the experimental data.

  12. MARCS-Model Stellar Atmospheres, and Their Application to the Photometric Calibration of the Spitzer-IRS

    E-Print Network [OSTI]

    L. Decin; P. W. Morris; P. N. Appleton; V. Charmandaris; L. Armus; J. R. Houck

    2004-06-03

    We describe state-of-the-art MARCS-code model atmospheres generated for a group of A dwarf, G dwarf, and late-G to mid-K giant standard stars, selected to photometrically calibrate the Spitzer-IRS, and compare the synthetic spectra to observations of HR 6688, HR 6705, and HR 7891. The general calibration processes and uncertainties are briefly described, and the differences between various templated composite spectra of the standards are addressed. In particular, a contrast between up-to-date model atmospheres and previously published composite and synthetic spectra is illustrated for wavelength ranges around 8um (where the SiO Delta(v) = 1 band occurs for the cooler standards) and lambda greater than 20um, where the use of the Engelke function will lead to increasingly large discrepancies due to the neglect of gravity in cool stars. At this point, radiometric requirements are being met, absolute flux calibration uncertainties (1-sigma) are ~20% in the SH and LH, and ~15% in the SL and LL data, and order-to-order flux uncertainties are ~10% or less. Iteration between the MARCS model atmosphere inputs and the data processing will improve the S/N ratios and calibration accuracies.

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

    SciTech Connect (OSTI)

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

    2014-09-01

    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 6.8×1014 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 1.2×1016 to 2.5×1016 Bq and estimates for the facility in Indonesia vary from 6.1×1013 to 3.6×1014 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.

  14. Thermodynamic properties of mesoscale convective systems observed during BAMEX

    SciTech Connect (OSTI)

    Correia, James; Arritt, R.

    2008-11-01

    Dropsonde observations from the Bow-echo and Mesoscale convective vortex EXperiment (BAMEX) are used to document the spatio-temporal variability of temperature, moisture and wind within mesoscale convective systems (MCSs). Onion type sounding structures are found throughout the stratiform region of MCSs but the temperature and moisture variability is large. Composite soundings were constructed and statistics of thermodynamic variability were generated within each sub-region of the MCS. The calculated air vertical velocity helped identify subsaturated downdrafts. We found that lapse rates within the cold pool varied markedly throughout the MCS. Layered wet bulb potential temperature profiles seem to indicate that air within the lowest several km comes from a variety of source regions. We also found that lapse rate transitions across the 0 C level were more common than isothermal, melting layers. We discuss the implications these findings have and how they can be used to validate future high resolution numerical simulations of MCSs.

  15. Quantum fluctuations and saturable absorption in mesoscale lasers

    SciTech Connect (OSTI)

    Roy-Choudhury, Kaushik [Department of Physics and Astronomy, University of Southern California, Los Angeles, California 90089-0484 (United States); Levi, A. F. J. [Department of Physics and Astronomy, University of Southern California, Los Angeles, California 90089-0484 (United States); Department of Electrical Engineering, University of Southern California, Los Angeles, California 90089-2533 (United States)

    2011-04-15

    We present a quantum-mechanical treatment of fluctuations and saturable absorption in mesoscale lasers. The time evolution of the density matrix is obtained from numerical integration and field-field and intensity-intensity correlations are calculated to obtain steady-state linewidth and photon statistics. Inclusion of a saturable absorber in the otherwise homogeneous medium is shown to suppress lasing, increase fluctuations, and enhance spontaneous emission near threshold.

  16. The effect of horizontal resolution on simulation quality in the Community Atmospheric Model, CAM5.1

    SciTech Connect (OSTI)

    Wehner, Michael F.; Reed, Kevin A.; Li, Fuyu; Prabhat, -; Bacmeister, Julio; Chen, Cheng -Ta; Paciorek, Christopher; Gleckler, Peter J.; Sperber, Kenneth R.; Collins, William D.; Gettelman, Andrew; Jablonowski, Christiane

    2014-11-05

    We present an analysis of version 5.1 of the Community Atmospheric Model (CAM5.1) at a high horizontal resolution. Intercomparison of this global model at approximately 0.25°, 1°, and 2° is presented for extreme daily precipitation as well as for a suite of seasonal mean fields. In general, extreme precipitation amounts are larger in high resolution than in lower-resolution configurations. In many but not all locations and/or seasons, extreme daily precipitation rates in the high-resolution configuration are higher and more realistic. The high-resolution configuration produces tropical cyclones up to category 5 on the Saffir-Simpson scale and a comparison to observations reveals both realistic and unrealistic model behavior. In the absence of extensive model tuning at high resolution, simulation of many of the mean fields analyzed in this study is degraded compared to the tuned lower-resolution public released version of the model.

  17. The effect of horizontal resolution on simulation quality in the Community Atmospheric Model, CAM5.1

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Wehner, Michael F.; Reed, Kevin A.; Li, Fuyu; Prabhat, -; Bacmeister, Julio; Chen, Cheng -Ta; Paciorek, Christopher; Gleckler, Peter J.; Sperber, Kenneth R.; Collins, William D.; et al

    2014-11-05

    We present an analysis of version 5.1 of the Community Atmospheric Model (CAM5.1) at a high horizontal resolution. Intercomparison of this global model at approximately 0.25°, 1°, and 2° is presented for extreme daily precipitation as well as for a suite of seasonal mean fields. In general, extreme precipitation amounts are larger in high resolution than in lower-resolution configurations. In many but not all locations and/or seasons, extreme daily precipitation rates in the high-resolution configuration are higher and more realistic. The high-resolution configuration produces tropical cyclones up to category 5 on the Saffir-Simpson scale and a comparison to observations revealsmore »both realistic and unrealistic model behavior. In the absence of extensive model tuning at high resolution, simulation of many of the mean fields analyzed in this study is degraded compared to the tuned lower-resolution public released version of the model.« less

  18. Computational Modeling of Self-organization of Dislocations and...

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

    Computational Modeling of Self-organization of Dislocations and Mesoscale Deformation of Metals Event Sponsor: Mathematics and Computing Science - LANS Seminar Start Date: Jun 19...

  19. is typical of atmospheric chemistry. Years of field, laboratory and modelling studies indi-

    E-Print Network [OSTI]

    Shoubridge, Eric

    that, in the atmosphere, particle nuclea- tion and growth might involve both gas and condensed happenswhenotheratmosphericcomponents, such as anthropogenic hydrocarbons and nitrogen oxides, are added to the mix, as these compounds­41 (2008). 2. Kiendler-Scharr, A. etal. Nature 461, 381­384 (2009). 3. Tunved, P. etal. Science 312, 261

  20. A Hydrogen Atmosphere Spectral Model Applied to the Neutron Star X7 in the Globular Cluster 47 Tucanae

    E-Print Network [OSTI]

    Craig O. Heinke; George B. Rybicki; Ramesh Narayan; Jonathan E. Grindlay

    2006-03-01

    Current X-ray missions are providing high-quality X-ray spectra from neutron stars (NSs) in quiescent low-mass X-ray binaries (qLMXBs). This has motivated us to calculate new hydrogen-atmosphere models, including opacity due to free-free absorption and Thomson scattering, thermal electron conduction, and self-irradiation by photons from the compact object. We have constructed a self-consistent grid of neutron star models covering a wide range of surface gravities as well as effective temperatures, which we make available to the scientific community. We present multi-epoch Chandra X-ray observations of the qLMXB X7 in the globular cluster 47 Tuc, which is remarkably nonvariable on timescales from minutes to years. Its high-quality X-ray spectrum is adequately fit by our hydrogen-atmosphere model without any hard power-law component or narrow spectral features. If a mass of 1.4 Msol is assumed, our spectral fits require that its radius be in the range R=14.5^{+1.8}_{-1.6} km (90% confidence), larger than expected from currently preferred models of NS interiors. If its radius is assumed to be 10 km, then a mass of M=2.20^{+0.03}_{-0.16} Msol is required. Using models with the appropriate surface gravity for each value of the mass and radius becomes important for interpretation of the highest quality data.

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

    E-Print Network [OSTI]

    2014-01-01

    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.

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

    E-Print Network [OSTI]

    2015-01-01

    K. : THE COMMUNITY EARTH SYSTEM MODEL, B. Am. Meteor. Soc. ,M. : The Community Earth System Model: A Framework forin the Community Earth System Model, Geo- scientific Model

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

    E-Print Network [OSTI]

    Thompson, R. L.

    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, ...

  4. A case study of the mesoscale and synoptic-scale heat and moisture budgets in the vicinity of a mesoscale convective complex 

    E-Print Network [OSTI]

    Dial, Greg Leander

    1990-01-01

    A CASE STUDY OF THE MESOSCALE AND SYNOPTIC-SCALE HEAT AND MOISTURE BUDGETS IN THE VICINITY OF A MESOSCALE CONVECTIVE COMPLEX A Thesis by GREG LEANDER DIAL Submitted to the Office of Graduate Studies of Texas A8 M University in partial...&j Leandor Dial Approved as lo style and content by: Kcnnctt& C, ftrunrti&lgc (Ctn&i& ol' Co&nn&ittcc) (I tcn&l&c&) Norman W. Na glc (Mcmbcr) E ar . ipscr (I les&I of Dcpartmcnt) I 1 a y I 9 &3 0 ABSTRACT A Case Study of the Mesoscale and Synoptic...

  5. 14th Conference on Harmonisation within Atmospheric Dispersion Modelling for Regulatory Purposes 2-6 October 2011, Kos, Greece THE "VOTRE AIR" PROJECT : DEVELOPMENT OF A MODELLING TOOL TO ASSESS THE REAL

    E-Print Network [OSTI]

    Mallet, Vivien

    resolution modelling tools like Urban'Air well reproduce the spatial distribution of atmospheric pollutants OF THE SYSTEM The "Votre Air" project has been designed to monitor the atmospheric pollution over Paris center of pollutants concentrations computed by the air dispersion model are immediately corrected by the assimilation

  6. Evolutionary games defined at the network mesoscale: The Public Jesus Gomez-Garden~es,1,2,3,a)

    E-Print Network [OSTI]

    Sánchez, Angel "Anxo"

    Evolutionary games defined at the network mesoscale: The Public Goods game Jesu´s Go on the mesoscale level of large social systems, that promotes cooperation. Moreover, we fur- ther show

  7. TextureCam: A Smart Camera for Microscale, Mesoscale, and Deep Space Applications. David R. Thomp-, William Abbey2

    E-Print Network [OSTI]

    Wagstaff, Kiri L.

    TextureCam: A Smart Camera for Microscale, Mesoscale, and Deep Space Applications. David R. Thomp variable illumination. #12;Mesoscale Geologic Surface Classification: Re- cent tests on images collected

  8. Analysis of 11 june 2003 mesoscale convective vortex genesis using weather surveillance radar ??88 doppler (wsr-88d) 

    E-Print Network [OSTI]

    Reynolds, Amber Elizabeth

    2009-05-15

    Mesoscale convective vortices (MCVs), which typically form within the stratiform rain of some mesoscale convective systems (MCSs), may persist for days, often regenerating convection daily. Long-lived MCVs can produce as much precipitation as a...

  9. NATURE |VOL 407 |12 OCTOBER 2000 |www.nature.com 695 A mesoscale phytoplankton bloom in the

    E-Print Network [OSTI]

    Kudela, Raphael M.

    NATURE |VOL 407 |12 OCTOBER 2000 |www.nature.com 695 articles A mesoscale phytoplankton bloom report the results of a mesoscale iron fertilization experiment in the polar Southern Ocean, where

  10. NEW ATLAS9 AND MARCS MODEL ATMOSPHERE GRIDS FOR THE APACHE POINT OBSERVATORY GALACTIC EVOLUTION EXPERIMENT (APOGEE)

    SciTech Connect (OSTI)

    Meszaros, Sz.; Allende Prieto, C.; De Vicente, A.; Edvardsson, B.; Gustafsson, B.; Castelli, F.; Garcia Perez, A. E.; Majewski, S. R.; Plez, B.; Schiavon, R.; Shetrone, M.

    2012-10-01

    We present a new grid of model photospheres for the SDSS-III/APOGEE survey of stellar populations of the Galaxy, calculated using the ATLAS9 and MARCS codes. New opacity distribution functions were generated to calculate ATLAS9 model photospheres. MARCS models were calculated based on opacity sampling techniques. The metallicity ([M/H]) spans from -5 to 1.5 for ATLAS and -2.5 to 0.5 for MARCS models. There are three main differences with respect to previous ATLAS9 model grids: a new corrected H{sub 2}O line list, a wide range of carbon ([C/M]) and {alpha} element [{alpha}/M] variations, and solar reference abundances from Asplund et al. The added range of varying carbon and {alpha}-element abundances also extends the previously calculated MARCS model grids. Altogether, 1980 chemical compositions were used for the ATLAS9 grid and 175 for the MARCS grid. Over 808,000 ATLAS9 models were computed spanning temperatures from 3500 K to 30,000 K and log g from 0 to 5, where larger temperatures only have high gravities. The MARCS models span from 3500 K to 5500 K, and log g from 0 to 5. All model atmospheres are publicly available online.

  11. Atmospheric Environment 38 (2004) 44274436 Statistical comparison of observed and CMAQ modeled daily

    E-Print Network [OSTI]

    Jun, Mikyoung

    2004-01-01

    2004 Abstract New statistical procedures to evaluate the Models-3/Community Multiscale Air Quality reserved. Keywords: Air quality model; Model evaluation; Space­time process; Separable covariance function 1. Introduction The Models-3/Community Multiscale Air Quality (CMAQ) modeling system has been

  12. Atmospheric Properties from the 2006 Niamey Deployment and Climate Simulation with a Geodesic Grid Coupled Climate Model Third Quarter 2008

    SciTech Connect (OSTI)

    JH Mather; DA Randall; CJ Flynn

    2008-06-30

    In 2008, the Atmospheric Radiation Measurement (ARM) Program and the Climate Change Prediction Program (CCPP) have been asked to produce joint science metrics. For CCPP, the metrics will deal with a decade-long control simulation using geodesic grid-coupled climate model. For ARM, the metrics will deal with observations associated with the 2006 deployment of the ARM Mobile Facility (AMF) to Niamey, Niger. Specifically, ARM has been asked to deliver data products for Niamey that describe cloud, aerosol, and dust properties. This report describes the aerosol optical depth (AOD) product.

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

    SciTech Connect (OSTI)

    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

    2014-11-27

    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.

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

    E-Print Network [OSTI]

    2014-01-01

    2013), The Community Earth System Model: A framework forcycle in the CMIP5 Earth System Models, J. Clim. , 26(18),feedbacks in CMIP5 Earth System Models, J. Clim. , 26(15),

  15. Changing the Climate Sensitivity of an Atmospheric General Circulation Model through Cloud Radiative Adjustment

    E-Print Network [OSTI]

    Sokolov, Andrei P.

    Conducting probabilistic climate projections with a particular climate model requires the ability to vary the model’s characteristics, such as its climate sensitivity. In this study, the authors implement and validate a ...

  16. Mesoscale simulations of shock initiation in energetic materials characterized by three-dimensional nanotomography.

    SciTech Connect (OSTI)

    Long, Gregory T.; Brundage, Aaron L.; Wixom, Ryan R.; Tappan, Alexander Smith

    2009-08-01

    Three-dimensional shock simulations of energetic materials have been conducted to improve our understanding of initiation at the mesoscale. Vapor-deposited films of PETN and pressed powders of HNS were characterized with a novel three-dimensional nanotomographic technique. Detailed microstructures were constructed experimentally from a stack of serial electron micrographs obtained by successive milling and imaging in a dual-beam FIB/SEM. These microstructures were digitized and imported into a multidimensional, multimaterial Eulerian shock physics code. The simulations provided insight into the mechanisms of pore collapse in PETN and HNS samples with distinctly different three-dimensional pore morphology and distribution. This modeling effort supports investigations of microscale explosive phenomenology and elucidates mechanisms governing initiation of secondary explosives.

  17. Inferring the mesoscale structure of layered, edge-valued and time-varying networks

    E-Print Network [OSTI]

    Peixoto, Tiago P

    2015-01-01

    Many network systems are composed of interdependent but distinct types of interactions, which cannot be fully understood in isolation. These different types of interactions are often represented as layers, attributes on the edges or as a time-dependence of the network structure. Although they are crucial for a more comprehensive scientific understanding, these representations offer substantial challenges. Namely, it is an open problem how to precisely characterize the large or mesoscale structure of network systems in relation to these additional aspects. Furthermore, the direct incorporation of these features invariably increases the effective dimension of the network description, and hence aggravates the problem of overfitting, i.e. the use of overly-complex characterizations that mistake purely random fluctuations for actual structure. In this work, we propose a robust and principled method to tackle these problems, by constructing generative models of modular network structure, incorporating layered, attr...

  18. Atmospheric Test Models and Numerical Experiments for the Simulation of the Global Distributions of Weather Data Transponders III. Horizontal Distributions

    SciTech Connect (OSTI)

    Molenkamp, C.R.; Grossman, A.

    1999-12-20

    A network of small balloon-borne transponders which gather very high resolution wind and temperature data for use by modern numerical weather predication models has been proposed to improve the reliability of long-range weather forecasts. The global distribution of an array of such transponders is simulated using LLNL's atmospheric parcel transport model (GRANTOUR) with winds supplied by two different general circulation models. An initial study used winds from CCM3 with a horizontal resolution of about 3 degrees in latitude and longitude, and a second study used winds from NOGAPS with a 0.75 degree horizontal resolution. Results from both simulations show that reasonable global coverage can be attained by releasing balloons from an appropriate set of launch sites.

  19. 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

  20. Phase behavior and mesoscale solubilization in aqueous solutions of hydrotropes

    E-Print Network [OSTI]

    Deepa Subramanian; Mikhail A. Anisimov

    2013-09-27

    Hydrotropes are amphiphilic molecules that are too small to spontaneously form equilibrium structures in aqueous solutions, but form dynamic, noncovalent assemblies, referred to as clusters. In the presence of a hydrophobic compound, these clusters seem to get stabilized leading to the formation of long-lived, highly stable mesoscopic droplets, a phenomenon that we call mesoscale solubilization. In this work, we focus on the unusual mesoscopic properties of aqueous solutions of a nonionic hydrotrope, namely tertiary butyl alcohol (TBA), on addition of various hydrophobic compounds. Aqueous TBA solutions, in about 3 to 8 mol percent TBA concentration range and about 0 to 25 deg. C temperature range, show the presence of short-ranged (0.5 nm), short-lived (tens of picoseconds) molecular clusters which result in anomalies of the thermodynamic properties. These clusters are transient but do not relax by diffusion, thus distinctly different from conventional concentration fluctuations. In this concentration and temperature range, upon the addition of a third (more hydrophobic) component to TBA-water solutions, long-lived mesoscopic droplets of about 100 nm size are observed. In this work, we clarify the ambiguity behind the definition of solubility and elucidate the phenomenon of mesoscale solubilization. A systematic study of the macro and meso phase behavior of three ternary systems TBA-water-propylene oxide, TBA-water-isobutyl alcohol, and TBA-water-cyclohexane has been carried out. We differentiate between molecular solubility, mesoscale solubilization, and macroscopic phase separation. We have confirmed that practically stable aqueous colloids can be created from small molecules, without addition of surfactants or polymers. Such kind of novel materials may find applications in the design of various processes and products, ranging from pharmaceuticals to cosmetics and agrochemicals.