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1

The Mixed-Phase Arctic Cloud Experiment  

Science Conference Proceedings (OSTI)

The Mixed-Phase Arctic Cloud Experiment (M-PACE) was conducted from 27 September through 22 October 2004 over the Department of Energy's Atmospheric Radiation Measurement (ARM) Climate Research Facility (ACRF) on the North Slope of Alaska. The ...

J. Verlinde; J. Y. Harrington; V. T. Yannuzzi; A. Avramov; S. Greenberg; S. J. Richardson; C. P. Bahrmann; G. M. McFarquhar; G. Zhang; N. Johnson; M. R. Poellot; J. H. Mather; D. D. Turner; E. W. Eloranta; D. C. Tobin; R. Holz; B. D. Zak; M. D. Ivey; A. J. Prenni; P. J. DeMott; J. S. Daniel; G. L. Kok; K. Sassen; D. Spangenberg; P. Minnis; T. P. Tooman; M. Shupe; A. J. Heymsfield; R. Schofield

2007-02-01T23:59:59.000Z

2

Mesoscale Modeling During Mixed-Phase Arctic Cloud Experiment  

SciTech Connect

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

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

2005-03-18T23:59:59.000Z

3

Retrieval of Cloud Phase Using the Moderate Resolution Imaging Spectroradiometer Data during the Mixed-Phase Arctic Cloud Experiment  

SciTech Connect

Improving climate model predictions over Earth's polar regions requires a comprehensive knowledge of polar cloud microphysics. Over the Arctic, there is minimal contrast between the clouds and background snow surface, making it difficult to detect clouds and retrieve their phase from space. Snow and ice cover, temperature inversions, and the predominance of mixed-phase clouds make it even more difficult to determine cloud phase. Also, since determining cloud phase is the first step toward analyzing cloud optical depth, particle size, and water content, it is vital that the phase be correct in order to obtain accurate microphysical and bulk properties. Changes in these cloud properties will, in turn, affect the Arctic climate since clouds are expected to play a critical role in the sea ice albedo feedback. In this paper, the IR trispectral technique (IRTST) is used as a starting point for a WV and 11-{micro}m brightness temperature (T11) parameterization (WVT11P) of cloud phase using MODIS data. In addition to its ability to detect mixed-phase clouds, the WVT11P also has the capability to identify thin cirrus clouds overlying mixed or liquid phase clouds (multiphase ice). Results from the Atmospheric Radiation Measurement (ARM) MODIS phase model (AMPHM) are compared to the surface-based cloud phase retrievals over the ARM North Slope of Alaska (NSA) Barrow site and to in-situ data taken from University of North Dakota Citation (CIT) aircraft which flew during the Mixed-Phase Arctic Cloud Experiment (MPACE). It will be shown that the IRTST and WVT11P combined to form the AMPHM can achieve a relative high accuracy of phase discrimination compared to the surface-based retrievals. Since it only uses MODIS WV and IR channels, the AMPHM is robust in the sense that it can be applied to daytime, twilight, and nighttime scenes with no discontinuities in the output phase.

Spangenberg, D.; Minnis, P.; Shupe, M.; Uttal, T.; Poellot, M.

2005-03-18T23:59:59.000Z

4

Ice properties of single-layer stratocumulus during the Mixed-Phase Arctic Cloud Experiment  

E-Print Network (OSTI)

Ice properties of single-layer stratocumulus during the Mixed-Phase Arctic Cloud Experiment: 2 opportunity to study poorly understood ice formation processes in mixed-phase stratocumulus. Using, were not significant sources of ice based on parameterizations from existing studies. After surveying

5

Intercomparison of model simulations of mixed-phase clouds observed during the ARM Mixed-Phase Arctic Cloud Experiment. Part II: Multi-layered cloud  

SciTech Connect

Results are presented from an intercomparison of single-column and cloud-resolving model simulations of a deep, multi-layered, mixed-phase cloud system observed during the ARM Mixed-Phase Arctic Cloud Experiment. This cloud system was associated with strong surface turbulent sensible and latent heat fluxes as cold air flowed over the open Arctic Ocean, combined with a low pressure system that supplied moisture at mid-level. The simulations, performed by 13 single-column and 4 cloud-resolving models, generally overestimate the liquid water path and strongly underestimate the ice water path, although there is a large spread among the models. This finding is in contrast with results for the single-layer, low-level mixed-phase stratocumulus case in Part I of this study, as well as previous studies of shallow mixed-phase Arctic clouds, that showed an underprediction of liquid water path. The overestimate of liquid water path and underestimate of ice water path occur primarily when deeper mixed-phase clouds extending into the mid-troposphere were observed. These results suggest important differences in the ability of models to simulate Arctic mixed-phase clouds that are deep and multi-layered versus shallow and single-layered. In general, models with a more sophisticated, two-moment treatment of the cloud microphysics produce a somewhat smaller liquid water path that is closer to observations. The cloud-resolving models tend to produce a larger cloud fraction than the single-column models. The liquid water path and especially the cloud fraction have a large impact on the cloud radiative forcing at the surface, which is dominated by the longwave flux for this case.

Morrison, H; McCoy, R B; Klein, S A; Xie, S; Luo, Y; Avramov, A; Chen, M; Cole, J; Falk, M; Foster, M; Genio, A D; Harrington, J; Hoose, C; Khairoutdinov, M; Larson, V; Liu, X; McFarquhar, G; Poellot, M; Shipway, B; Shupe, M; Sud, Y; Turner, D; Veron, D; Walker, G; Wang, Z; Wolf, A; Xu, K; Yang, F; Zhang, G

2008-02-27T23:59:59.000Z

6

ARM - Field Campaign - FIRE-Arctic Cloud Experiment/SHEBA  

NLE Websites -- All DOE Office Websites (Extended Search)

g-meter, the Pilewskie Solar Spectral Flux Radiometer (SSFR), the NASA-GoddardU. of Wash. Spectral Scanning Radiometer, and the SPEC Inc. Cloud Particle Imager. This was the...

7

LES Simulations of Roll Clouds Observed During Mixed- Phase Arctic Cloud Experiment  

SciTech Connect

Roll clouds, and associated roll convection, are fairly common features of the atmospheric boundary layer. While these organized cumuliform clouds are found over many regions of the planet, they are quite ubiquitous near the edge of the polar ice sheets. In particular, during periods of off-ice flow, when cold polar air flows from the ice pack over the relatively warm ocean water, strong boundary layer convection develops along with frequent rolls. According to Bruemmer and Pohlman (2000), most of the total cloud cover in the Arctic is due to roll clouds. In an effort to examine the influences of mixed-phase microphysics on the boundary layer evolution of roll clouds during off-ice flow, Olsson and Harrington (2000) used a 2D mesoscale model coupled to a bulk microphysical scheme (see Section 2). Their results showed that mixed-phase clouds produced more shallow boundary layers with weaker turbulence than liquid-phase cases. Furthermore, their results showed that because of th e reduced turbulent drag on the atmosphere in the mixed-phase case, regions of mesoscale divergence in the marginal ice-zone were significantly affected. A follow-up 2D study (Harrington and Olsson 2001) showed that the reduced turbulent intensity in mixed-phase cases was due to precipitation. Ice precipitation caused downdraft stabilization which fed back and caused a reduction in the surface heat fluxes. In this work, we extend the work of Olsson and Harrington (2000) and Harrington and Olsson (2001) by examining the impacts of ice microphysics on roll convection. We will present results that illustrate how microphysics alters roll cloud structure and dynamics.

Greenberg, S.D.; Harrington, J.Y.; Prenni, A.; DeMott, P.

2005-03-18T23:59:59.000Z

8

Vertical Motions in Arctic Mixed-Phase Stratiform Clouds  

Science Conference Proceedings (OSTI)

The characteristics of Arctic mixed-phase stratiform clouds and their relation to vertical air motions are examined using ground-based observations during the Mixed-Phase Arctic Cloud Experiment (MPACE) in Barrow, Alaska, during fall 2004. The ...

Matthew D. Shupe; Pavlos Kollias; P. Ola G. Persson; Greg M. McFarquhar

2008-04-01T23:59:59.000Z

9

Intercomparison of model simulations of mixed-phase clouds observed during the ARM Mixed-Phase Arctic Cloud Experiment. Part I: Single layer cloud  

SciTech Connect

Results are presented from an intercomparison of single-column and cloud-resolving model simulations of a cold-air outbreak mixed-phase stratocumulus cloud observed during the Atmospheric Radiation Measurement (ARM) program's Mixed-Phase Arctic Cloud Experiment. The observed cloud occurred in a well-mixed boundary layer with a cloud top temperature of -15 C. The observed liquid water path of around 160 g m{sup -2} was about two-thirds of the adiabatic value and much greater than the mass of ice crystal precipitation which when integrated from the surface to cloud top was around 15 g m{sup -2}. The simulations were performed by seventeen single-column models (SCMs) and nine cloud-resolving models (CRMs). While the simulated ice water path is generally consistent with the observed values, the median SCM and CRM liquid water path is a factor of three smaller than observed. Results from a sensitivity study in which models removed ice microphysics indicate that in many models the interaction between liquid and ice-phase microphysics is responsible for the large model underestimate of liquid water path. Despite this general underestimate, the simulated liquid and ice water paths of several models are consistent with the observed values. Furthermore, there is some evidence that models with more sophisticated microphysics simulate liquid and ice water paths that are in better agreement with the observed values, although considerable scatter is also present. Although no single factor guarantees a good simulation, these results emphasize the need for improvement in the model representation of mixed-phase microphysics. This case study, which has been well observed from both aircraft and ground-based remote sensors, could be a benchmark for model simulations of mixed-phase clouds.

Klein, S A; McCoy, R B; Morrison, H; Ackerman, A; Avramov, A; deBoer, G; Chen, M; Cole, J; DelGenio, A; Golaz, J; Hashino, T; Harrington, J; Hoose, C; Khairoutdinov, M; Larson, V; Liu, X; Luo, Y; McFarquhar, G; Menon, S; Neggers, R; Park, S; Poellot, M; von Salzen, K; Schmidt, J; Sednev, I; Shipway, B; Shupe, M; Spangenberg, D; Sud, Y; Turner, D; Veron, D; Falk, M; Foster, M; Fridlind, A; Walker, G; Wang, Z; Wolf, A; Xie, S; Xu, K; Yang, F; Zhang, G

2008-02-27T23:59:59.000Z

10

Intercomparison of model simulations of mixed-phase clouds observed during the ARM Mixed-Phase Arctic Cloud Experiment. Part I: Single layer cloud  

SciTech Connect

Results are presented from an intercomparison of single-column and cloud-resolving model simulations of a cold-air outbreak mixed-phase stratocumulus cloud observed during the Atmospheric Radiation Measurement (ARM) program's Mixed-Phase Arctic Cloud Experiment. The observed cloud occurred in a well-mixed boundary layer with a cloud top temperature of -15 C. The observed average liquid water path of around 160 g m{sup -2} was about two-thirds of the adiabatic value and much greater than the average mass of ice crystal precipitation which when integrated from the surface to cloud top was around 15 g m{sup -2}. The simulations were performed by seventeen single-column models (SCMs) and nine cloud-resolving models (CRMs). While the simulated ice water path is generally consistent with the observed values, the median SCM and CRM liquid water path is a factor of three smaller than observed. Results from a sensitivity study in which models removed ice microphysics suggest that in many models the interaction between liquid and ice-phase microphysics is responsible for the large model underestimate of liquid water path. Despite this general underestimate, the simulated liquid and ice water paths of several models are consistent with the observed values. Furthermore, there is evidence that models with more sophisticated microphysics simulate liquid and ice water paths that are in better agreement with the observed values, although considerable scatter is also present. Although no single factor guarantees a good simulation, these results emphasize the need for improvement in the model representation of mixed-phase microphysics.

Klein, Stephen A.; McCoy, Renata B.; Morrison, Hugh; Ackerman, Andrew S.; Avramov, Alexander; de Boer, Gijs; Chen, Mingxuan; Cole, Jason N.S.; Del Genio, Anthony D.; Falk, Michael; Foster, Michael J.; Fridlind, Ann; Golaz, Jean-Christophe; Hashino, Tempei; Harrington, Jerry Y.; Hoose, Corinna; Khairoutdinov, Marat F.; Larson, Vincent E.; Liu, Xiaohong; Luo, Yali; McFarquhar, Greg M.; Menon, Surabi; Neggers, Roel A. J.; Park, Sungsu; Poellot, Michael R.; Schmidt, Jerome M.; Sednev, Igor; Shipway, Ben J.; Shupe, Matthew D.; Spangenberg, Douglas A.; Sud, Yogesh C.; Turner, David D.; Veron, Dana E.; von Salzen, Knut; Walker, Gregory K.; Wang, Zhien; Wolf, Audrey B.; Xie, Shaocheng; Xu, Kuan-Man; Yang, Fanglin; Zhang, Gong

2009-02-02T23:59:59.000Z

11

Evaluation of Mixed-Phase Cloud Parameterizations in Short-Range Weather Forecasts with CAM3 and AM2 for Mixed-Phase Arctic Cloud Experiment  

SciTech Connect

By making use of the in-situ data collected from the recent Atmospheric Radiation Measurement Mixed-Phase Arctic Cloud Experiment, we have tested the mixed-phase cloud parameterizations used in the two major U.S. climate models, the National Center for Atmospheric Research Community Atmosphere Model version 3 (CAM3) and the Geophysical Fluid Dynamics Laboratory climate model (AM2), under both the single-column modeling framework and the U.S. Department of Energy Climate Change Prediction Program-Atmospheric Radiation Measurement Parameterization Testbed. An improved and more physically based cloud microphysical scheme for CAM3 has been also tested. The single-column modeling tests were summarized in the second quarter 2007 Atmospheric Radiation Measurement metric report. In the current report, we document the performance of these microphysical schemes in short-range weather forecasts using the Climate Chagne Prediction Program Atmospheric Radiation Measurement Parameterizaiton Testbest strategy, in which we initialize CAM3 and AM2 with realistic atmospheric states from numerical weather prediction analyses for the period when Mixed-Phase Arctic Cloud Experiment was conducted.

Xie, S; Boyle, J; Klein, S; Liu, X; Ghan, S

2007-06-01T23:59:59.000Z

12

A FIRE-ACE/SHEBA Case Study of Mixed-Phase Arctic Boundary Layer Clouds: Entrainment Rate Limitations on Rapid Primary Ice Nucleation Processes  

Science Conference Proceedings (OSTI)

Observations of long-lived mixed-phase Arctic boundary layer clouds on 7 May 1998 during the First International Satellite Cloud Climatology Project (ISCCP) Regional Experiment (FIRE)–Arctic Cloud Experiment (ACE)/Surface Heat Budget of the Arctic ...

Ann M. Fridlind; Bastiaan van Diedenhoven; Andrew S. Ackerman; Alexander Avramov; Agnieszka Mrowiec; Hugh Morrison; Paquita Zuidema; Matthew D. Shupe

2012-01-01T23:59:59.000Z

13

Overview of Arctic Cloud and Radiation Characteristics  

Science Conference Proceedings (OSTI)

To provide a background for ARM's activities at the North Slope of Alaska/Adjacent Arctic Ocean sites, an overview is given of our current state of knowledge of Arctic cloud and radiation properties and processes. The authors describe the Arctic ...

Judith A. Curry; Julie L. Schramm; William B. Rossow; David Randall

1996-08-01T23:59:59.000Z

14

Observational and Theoretical Studies of Solar Radiation in Arctic Stratus Clouds  

Science Conference Proceedings (OSTI)

A series of clouds-radiation experiments was carried out in June 1980 in Arctic stratus clouds occurring over the Beaufort Sea using the NCAR Electra aircraft. This paper is an analysis of the hemispheric radiation fields obtained with Eppley ...

G. F. Herman; J. A. Curry

1984-01-01T23:59:59.000Z

15

Clouds at Arctic Atmospheric Observatories. Part II: Thermodynamic Phase Characteristics  

Science Conference Proceedings (OSTI)

Cloud phase defines many cloud properties and determines the ways in which clouds interact with other aspects of the climate system. The occurrence fraction and characteristics of clouds distinguished by their phase are examined at three Arctic ...

Matthew D. Shupe

2011-03-01T23:59:59.000Z

16

Investigation of Microphysical Parameterizations of Snow and Ice in Arctic Clouds during M-PACE through ModelObservation Comparisons  

E-Print Network (OSTI)

Investigation of Microphysical Parameterizations of Snow and Ice in Arctic Clouds during M the microphysical properties of Arctic mixed-phase stratocumulus. Intensive measurements taken during the Department of Energy Atmospheric Radiation Measurement Program Mixed-Phase Arctic Cloud Experiment (M

Solomon, Amy

17

Intercomparison of model simulations of mixed-phase clouds observed during the ARM Mixed-Phase Arctic Cloud Experiment. Part I: Single layer cloud  

E-Print Network (OSTI)

simulation that is in the ice-phase. Note that the y-axis isradiative properties of ice and mixed-phase clouds. Quart.include liquid-phase only, ice-phase only, and mixed-phase.

Klein, Stephen A.

2009-01-01T23:59:59.000Z

18

Dynamical and Microphysical Characteristics of Arctic Clouds during BASE  

Science Conference Proceedings (OSTI)

In this study, observations from aircraft, Doppler radar, and LANDSAT are used to better understand dynamical and microphysical characteristics of low-level Arctic clouds for climate change studies. Observations during the Beaufort and Arctic ...

I. Gultepe; G. Isaac; D. Hudak; R. Nissen; J. W. Strapp

2000-04-01T23:59:59.000Z

19

Turbulence Structure of Arctic Stratus Clouds Derived from Measurements and Calculations  

Science Conference Proceedings (OSTI)

Results are presented from a detailed case study of an Arctic stratus cloud over the Fram Strait that is based on aircraft measurements and model calculations. The measurements have been performed during MIZEX 1984 (Marginal Ice Zone Experiment) ...

Jörg E. Finger; Peter Wendling

1990-06-01T23:59:59.000Z

20

Nighttime Cloud Detection Over the Arctic Using AVHRR Data  

NLE Websites -- All DOE Office Websites (Extended Search)

Cloud Detection Over the Arctic Cloud Detection Over the Arctic Using AVHRR Data D. A. Spangenberg, D. R. Doelling, and V. Chakrapani Analytical Services & Materials, Inc. Hampton, Virginia P. Minnis National Aeronautics and Space Administration Hampton, Virginia T. Uttal National Oceanic and Atmospheric Administration Boulder, Colorado Introduction Clouds play an important role in the Arctic energy budget. The magnitude and significance of the radiative impact of polar clouds, however, are not well known. Polar nocturnal clouds are often warmer or at the same temperature as the background snow surface, complicating cloud detection. Also, these clouds tend to be thin, with lower emittances than clouds occurring during the summer. Using only the infrared (IR) channels of satellite data to characterize cloud amount and distribution in the Arctic is

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


21

Observed Relationships between Arctic Longwave Cloud Forcing and Cloud Parameters Using a Neural Network  

Science Conference Proceedings (OSTI)

A neural network technique is used to quantify relationships involved in cloud–radiation feedbacks based on observations from the Surface Heat Budget of the Arctic (SHEBA) project. Sensitivities of longwave cloud forcing (CFL) to cloud parameters ...

Yonghua Chen; Filipe Aires; Jennifer A. Francis; James R. Miller

2006-08-01T23:59:59.000Z

22

Towards a Characterization of Arctic Mixed-Phase Clouds  

NLE Websites -- All DOE Office Websites (Extended Search)

Towards a Characterization of Arctic Mixed-Phase Clouds Towards a Characterization of Arctic Mixed-Phase Clouds Shupe, Matthew CIRES/NOAA/ETL Kollias, Pavlos Brookhaven National Laboratory Category: Cloud Properties Mixed-phase clouds play a unique role in the Arctic, where the delicate balance of phases in these clouds can have a profound impact on the surface radiation balance and various cloud-atmosphere-radiation-surface feedback processes. A better understanding of these clouds is clearly important and has been a recent objective of the ARM program. To this end, multiple sensors including radar, lidar, and temperature soundings, have been utilized in an automated cloud type classification scheme for clouds observed at the North Slope of Alaska site. The performance of this new algorithm at identifying mixed-phase cloud conditions is compared with an

23

Relationships between Arctic Sea Ice and Clouds during Autumn  

Science Conference Proceedings (OSTI)

The connection between sea ice variability and cloud cover over the Arctic seas during autumn is investigated by analyzing the 40-yr ECMWF Re-Analysis (ERA-40) products and the Television and Infrared Observation Satellite (TIROS) Operational ...

Axel J. Schweiger; Ron W. Lindsay; Steve Vavrus; Jennifer A. Francis

2008-09-01T23:59:59.000Z

24

Cirriform Rotor Cloud Observed on a Canadian Arctic Ice Cap  

Science Conference Proceedings (OSTI)

A thin rotor cloud was observed on the lee side of Penny Ice Cap in the Canadian Arctic on 21 April 1996. The cloud consisted of thin cirriform layers, so that its motion was clearly observed. By means of time-lapse camera photography, the ...

Hisashi Ozawa; Kumiko Goto-Azuma; Koyuru Iwanami; Roy M. Koerner

1998-06-01T23:59:59.000Z

25

On the Relationship between Thermodynamic Structure and Cloud Top, and Its Climate Significance in the Arctic  

Science Conference Proceedings (OSTI)

Cloud and thermodynamic characteristics from three Arctic observation sites are investigated to understand the collocation between low-level clouds and temperature inversions. A regime where cloud top was 100–200 m above the inversion base [cloud ...

Joseph Sedlar; Matthew D. Shupe; Michael Tjernström

2012-04-01T23:59:59.000Z

26

Arctic Ocean Radiative Fluxes and Cloud Forcing Estimated from the ISCCP C2 Cloud Dataset, 1983?1990  

Science Conference Proceedings (OSTI)

Radiative fluxes and cloud forcings for the ocean areas of the Arctic are computed from the monthly cloud product of the International Satellite Cloud Climatology Project (ISCCP) for 1983?90. Spatially averaged short-wave fluxes compare well with ...

Axel J. Schweiger; Jeffrey R. Key

1994-08-01T23:59:59.000Z

27

Microphysical Properties of Single and Mixed-Phase Arctic Clouds Derived from AERI Observations  

SciTech Connect

A novel new approach to retrieve cloud microphysical properties from mixed-phase clouds is presented. This algorithm retrieves cloud optical depth, ice fraction, and the effective size of the water and ice particles from ground-based, high-resolution infrared radiance observations. The theoretical basis is that the absorption coefficient of ice is stronger than that of liquid water from 10-13 mm, whereas liquid water is more absorbing than ice from 16-25 um. However, due to strong absorption in the rotational water vapor absorption band, the 16-25 um spectral region becomes opaque for significant water vapor burdens (i.e., for precipitable water vapor amounts over approximately 1 cm). The Arctic is characterized by its dry and cold atmosphere, as well as a preponderance of mixed-phase clouds, and thus this approach is applicable to Arctic clouds. Since this approach uses infrared observations, cloud properties are retrieved at night and during the long polar wintertime period. The analysis of the cloud properties retrieved during a 7 month period during the Surface Heat Budget of the Arctic (SHEBA) experiment demonstrates many interesting features. These results show a dependence of the optical depth on cloud phase, differences in the mode radius of the water droplets in liquid-only and mid-phase clouds, a lack of temperature dependence in the ice fraction for temperatures above 240 K, seasonal trends in the optical depth with the clouds being thinner in winter and becoming more optically thick in the late spring, and a seasonal trend in the effective size of the water droplets in liquid-only and mixed-phase clouds that is most likely related to aerosol concentration.

Turner, David D.

2003-06-01T23:59:59.000Z

28

Major Cloud Plumes in the Arctic and Their Relation to Fronts and Ice Movement  

Science Conference Proceedings (OSTI)

A study of the movement of orographic cloud plumes from one island to another in the Svalbard-Novaya Zemlya region of the Barents Sea revealed a close association with similar movements of arctic fronts. Strong northerly winds behind arctic ...

Robert W. Fett

1992-06-01T23:59:59.000Z

29

The Influence of Changes in Cloud Cover on Recent Surface Temperature Trends in the Arctic  

Science Conference Proceedings (OSTI)

A method is presented to assess the influence of changes in Arctic cloud cover on the surface temperature trend, allowing for a more robust diagnosis of causes for surface warming or cooling. Seasonal trends in satellite-derived Arctic surface ...

Yinghui Liu; Jeffrey R. Key; Xuanji Wang

2008-02-01T23:59:59.000Z

30

Intercomparison of Bulk Cloud Microphysics Schemes in Mesoscale Simulations of Springtime Arctic Mixed-Phase Stratiform Clouds  

Science Conference Proceedings (OSTI)

A persistent, weakly forced, horizontally extensive mixed-phase boundary layer cloud observed on 4–5 May 1998 during the Surface Heat Budget of the Arctic Ocean (SHEBA)/First International Satellite Cloud Climatology Project (ISCCP) Regional ...

H. Morrison; J. O. Pinto

2006-07-01T23:59:59.000Z

31

TOWARDS A CHARACTERIZATION OF ARCTIC MIXED-PHASE CLOUDS CIRES/NOAA/ETL  

E-Print Network (OSTI)

, radar-based retrieval methods. On average, mixed-phase cloud ice particle mean diameters increase fromTOWARDS A CHARACTERIZATION OF ARCTIC MIXED-PHASE CLOUDS Shupe, M. CIRES/NOAA/ETL Kollias, P Laboratory P.O. Box, Upton, NY www.bnl.gov ABSTRACT Mixed-phase clouds play a unique role in the Arctic

32

Indirect and Semi-Direct Aerosol Campaign: The Impact of Arctic Aerosols on Clouds  

SciTech Connect

A comprehensive dataset of microphysical and radiative properties of aerosols and clouds in the arctic boundary layer in the vicinity of Barrow, Alaska was collected in April 2008 during the Indirect and Semi-Direct Aerosol Campaign (ISDAC) sponsored by the Department of Energy Atmospheric Radiation Measurement (ARM) and Atmospheric Science Programs. The primary aim of ISDAC was to examine indirect effects of aerosols on clouds that contain both liquid and ice water. The experiment utilized the ARM permanent observational facilities at the North Slope of Alaska (NSA) in Barrow. These include a cloud radar, a polarized micropulse lidar, and an atmospheric emitted radiance interferometer as well as instruments specially deployed for ISDAC measuring aerosol, ice fog, precipitation and spectral shortwave radiation. The National Research Council of Canada Convair-580 flew 27 sorties during ISDAC, collecting data using an unprecedented 42 cloud and aerosol instruments for more than 100 hours on 12 different days. Data were obtained above, below and within single-layer stratus on 8 April and 26 April 2008. These data enable a process-oriented understanding of how aerosols affect the microphysical and radiative properties of arctic clouds influenced by different surface conditions. Observations acquired on a heavily polluted day, 19 April 2008, are enhancing this understanding. Data acquired in cirrus on transit flights between Fairbanks and Barrow are improving our understanding of the performance of cloud probes in ice. Ultimately the ISDAC data will be used to improve the representation of cloud and aerosol processes in models covering a variety of spatial and temporal scales, and to determine the extent to which long-term surface-based measurements can provide retrievals of aerosols, clouds, precipitation and radiative heating in the Arctic.

McFarquhar, Greg; Ghan, Steven J.; Verlinde, J.; Korolev, Alexei; Strapp, J. Walter; Schmid, Beat; Tomlinson, Jason M.; Wolde, Mengistu; Brooks, Sarah D.; Cziczo, Daniel J.; Dubey, Manvendra K.; Fan, Jiwen; Flynn, Connor J.; Gultepe, Ismail; Hubbe, John M.; Gilles, Mary K.; Laskin, Alexander; Lawson, Paul; Leaitch, W. R.; Liu, Peter S.; Liu, Xiaohong; Lubin, Dan; Mazzoleni, Claudio; Macdonald, A. M.; Moffet, Ryan C.; Morrison, H.; Ovchinnikov, Mikhail; Shupe, Matthew D.; Turner, David D.; Xie, Shaocheng; Zelenyuk, Alla; Bae, Kenny; Freer, Matthew; Glen, Andrew

2011-02-01T23:59:59.000Z

33

Intercomparison of cloud model simulations of Arctic mixed-phase boundary layer clouds observed during SHEBA/FIRE-ACE  

SciTech Connect

An intercomparison of six cloud-resolving and large-eddy simulation models is presented. This case study is based on observations of a persistent mixed-phase boundary layer cloud gathered on 7 May, 1998 from the Surface Heat Budget of Arctic Ocean (SHEBA) and First ISCCP Regional Experiment - Arctic Cloud Experiment (FIRE-ACE). Ice nucleation is constrained in the simulations in a way that holds the ice crystal concentration approximately fixed, with two sets of sensitivity runs in addition to the baseline simulations utilizing different specified ice nucleus (IN) concentrations. All of the baseline and sensitivity simulations group into two distinct quasi-steady states associated with either persistent mixed-phase clouds or all-ice clouds after the first few hours of integration, implying the existence of multiple equilibria. These two states are associated with distinctly different microphysical, thermodynamic, and radiative characteristics. Most but not all of the models produce a persistent mixed-phase cloud qualitatively similar to observations using the baseline IN/crystal concentration, while small increases in the IN/crystal concentration generally lead to rapid glaciation and conversion to the all-ice state. Budget analysis indicates that larger ice deposition rates associated with increased IN/crystal concentrations have a limited direct impact on dissipation of liquid in these simulations. However, the impact of increased ice deposition is greatly enhanced by several interaction pathways that lead to an increased surface precipitation flux, weaker cloud top radiative cooling and cloud dynamics, and reduced vertical mixing, promoting rapid glaciation of the mixed-phase cloud for deposition rates in the cloud layer greater than about 1-2x10-5 g kg-1 s-1. These results indicate the critical importance of precipitation-radiative-dynamical interactions in simulating cloud phase, which have been neglected in previous fixed-dynamical parcel studies of the cloud phase parameter space. Large sensitivity to the IN/crystal concentration also suggests the need for improved understanding of ice nucleation and its parameterization in models.

Morrison, H.; Zuidema, Paquita; Ackerman, Andrew; Avramov, Alexander; de Boer, Gijs; Fan, Jiwen; Fridlind, Ann; Hashino, Tempei; Harrington, Jerry Y.; Luo, Yali; Ovchinnikov, Mikhail; Shipway, Ben

2011-06-16T23:59:59.000Z

34

Clouds at Arctic Atmospheric Observatories. Part I: Occurrence and Macrophysical Properties  

Science Conference Proceedings (OSTI)

Cloud observations over the past decade from six Arctic atmospheric observatories are investigated to derive estimates of cloud occurrence fraction, vertical distribution, persistence in time, diurnal cycle, and boundary statistics. Each ...

Matthew D. Shupe; Von P. Walden; Edwin Eloranta; Taneil Uttal; James R. Campbell; Sandra M. Starkweather; Masataka Shiobara

2011-03-01T23:59:59.000Z

35

Simulations of Arctic Mixed-Phase Clouds in Forecasts with CAM3 and AM2 for M-PACE  

SciTech Connect

Simulations of mixed-phase clouds in short-range forecasts with the National Center for Atmospheric Research Community Atmosphere Model version 3 (CAM3) and the Geophysical Fluid Dynamics Laboratory (GFDL) climate model (AM2) for the Mixed-Phase Arctic Cloud Experiment (M-PACE) are performed under the DOE CCPP-ARM Parameterization Testbed (CAPT), which initializes the climate models with analysis data produced from numerical weather prediction (NWP) centers. It is shown that CAM3 significantly underestimates the observed boundary layer mixed-phase clouds and cannot realistically simulate the variations with temperature and cloud height of liquid water fraction in the total cloud condensate based an oversimplified cloud microphysical scheme. In contrast, AM2 reasonably reproduces the observed boundary layer clouds while its clouds contain much less cloud condensate than CAM3 and the observations. Both models underestimate the observed cloud top and base for the boundary layer clouds. The simulation of the boundary layer mixed-phase clouds and their microphysical properties is considerably improved in CAM3 when a new physically based cloud microphysical scheme is used. The new scheme also leads to an improved simulation of the surface and top of the atmosphere longwave radiative fluxes in CAM3. It is shown that the Bergeron-Findeisen process, i.e., the ice crystal growth by vapor deposition at the expense of coexisting liquid water, is important for the models to correctly simulate the characteristics of the observed microphysical properties in mixed-phase clouds. Sensitivity tests show that these results are not sensitive to the analysis data used for model initializations. Increasing model horizontal resolution helps capture the subgrid-scale features in Arctic frontal clouds but does not help improve the simulation of the single-layer boundary layer clouds. Ice crystal number density has large impact on the model simulated mixed-phase clouds and their microphysical properties and needs to be accurately represented in climate models.

Xie, Shaocheng; Boyle, James; Klein, Stephen A.; Liu, Xiaohong; Ghan, Steven J.

2008-02-29T23:59:59.000Z

36

Simulating mixed-phase Arctic stratus clouds: Sensitivity to ice initiationmechanisms  

SciTech Connect

The importance of Arctic mixed-phase clouds on radiation and the Arctic climate is well known. However, the development of mixed-phase cloud parameterization for use in large scale models is limited by lack of both related observations and numerical studies using multidimensional models with advanced microphysics that provide the basis for understanding the relative importance of different microphysical processes that take place in mixed-phase clouds. To improve the representation of mixed-phase cloud processes in the GISS GCM we use the GISS single-column model coupled to a bin resolved microphysics (BRM) scheme that was specially designed to simulate mixed-phase clouds and aerosol-cloud interactions. Using this model with the microphysical measurements obtained from the DOE ARM Mixed-Phase Arctic Cloud Experiment (MPACE) campaign in October 2004 at the North Slope of Alaska, we investigate the effect of ice initiation processes and Bergeron-Findeisen process (BFP) on glaciation time and longevity of single-layer stratiform mixed-phase clouds. We focus on observations taken during October 9th-10th, which indicated the presence of a single-layer mixed-phase clouds. We performed several sets of 12-hour simulations to examine model sensitivity to different ice initiation mechanisms and evaluate model output (hydrometeors concentrations, contents, effective radii, precipitation fluxes, and radar reflectivity) against measurements from the MPACE Intensive Observing Period. Overall, the model qualitatively simulates ice crystal concentration and hydrometeors content, but it fails to predict quantitatively the effective radii of ice particles and their vertical profiles. In particular, the ice effective radii are overestimated by at least 50%. However, using the same definition as used for observations, the effective radii simulated and that observed were more comparable. We find that for the single-layer stratiform mixed-phase clouds simulated, process of ice phase initiation due to freezing of supercooled water in both saturated and subsaturated (w.r.t. water) environments is as important as primary ice crystal origination from water vapor. We also find that the BFP is a process mainly responsible for the rates of glaciation of simulated clouds. These glaciation rates cannot be adequately represented by a water-ice saturation adjustment scheme that only depends on temperature and liquid and solid hydrometeors contents as is widely used in bulk microphysics schemes and are better represented by processes that also account for supersaturation changes as the hydrometeors grow.

Sednev, I.; Menon, S.; McFarquhar, G.

2009-04-10T23:59:59.000Z

37

Simulating mixed-phase Arctic stratus clouds: sensitivity to ice initiation mechanisms  

SciTech Connect

The importance of Arctic mixed-phase clouds on radiation and the Arctic climate is well known. However, the development of mixed-phase cloud parameterization for use in large scale models is limited by lack of both related observations and numerical studies using multidimensional models with advanced microphysics that provide the basis for understanding the relative importance of different microphysical processes that take place in mixed-phase clouds. To improve the representation of mixed-phase cloud processes in the GISS GCM we use the GISS single-column model coupled to a bin resolved microphysics (BRM) scheme that was specially designed to simulate mixed-phase clouds and aerosol-cloud interactions. Using this model with the microphysical measurements obtained from the DOE ARM Mixed-Phase Arctic Cloud Experiment (MPACE) campaign in October 2004 at the North Slope of Alaska, we investigate the effect of ice initiation processes and Bergeron-Findeisen process (BFP) on glaciation time and longevity of single-layer stratiform mixed-phase clouds. We focus on observations taken during 9th-10th October, which indicated the presence of a single-layer mixed-phase clouds. We performed several sets of 12-h simulations to examine model sensitivity to different ice initiation mechanisms and evaluate model output (hydrometeors concentrations, contents, effective radii, precipitation fluxes, and radar reflectivity) against measurements from the MPACE Intensive Observing Period. Overall, the model qualitatively simulates ice crystal concentration and hydrometeors content, but it fails to predict quantitatively the effective radii of ice particles and their vertical profiles. In particular, the ice effective radii are overestimated by at least 50%. However, using the same definition as used for observations, the effective radii simulated and that observed were more comparable. We find that for the single-layer stratiform mixed-phase clouds simulated, process of ice phase initiation due to freezing of supercooled water in both saturated and undersaturated (w.r.t. water) environments is as important as primary ice crystal origination from water vapor. We also find that the BFP is a process mainly responsible for the rates of glaciation of simulated clouds. These glaciation rates cannot be adequately represented by a water-ice saturation adjustment scheme that only depends on temperature and liquid and solid hydrometeors contents as is widely used in bulk microphysics schemes and are better represented by processes that also account for supersaturation changes as the hydrometeors grow.

Sednev, Igor; Sednev, I.; Menon, S.; McFarquhar, G.

2008-02-18T23:59:59.000Z

38

The Western Arctic Linkage Experiment (WALE): Overview and Synthesis  

Science Conference Proceedings (OSTI)

The primary goal of the Western Arctic Linkage Experiment (WALE) was to better understand uncertainties of simulated hydrologic and ecosystem dynamics of the western Arctic in the context of 1) uncertainties in the data available to drive the ...

A. D. McGuire; J. E. Walsh; J. S. Kimball; J. S. Clein; S. E. Euskirchen; S. Drobot; U. C. Herzfeld; J. Maslanik; R. B. Lammers; M. A. Rawlins; C. J. Vorosmarty; T. S. Rupp; W. Wu; M. Calef

2008-06-01T23:59:59.000Z

39

Influence of parameterized ice habit on simulated mixed phase Arctic clouds  

E-Print Network (OSTI)

Influence of parameterized ice habit on simulated mixed phase Arctic clouds Alexander Avramov1 12 February 2010. [1] The phase partitioning of cloud mass between liquid and ice in mixed phase clouds and its dependence on ambient ice nuclei (IN) concentrations and ice habit parameterizations

40

Ice Formation in Arctic Mixed-Phase Clouds: Insights from a 3-D Cloud-Resolving Model with Size-Resolved Aerosol and Cloud Microphysics  

SciTech Connect

The single-layer mixed-phase clouds observed during the Atmospheric Radiation Measurement (ARM) program’s Mixed-Phase Arctic Cloud Experiment (MPACE) are simulated with a 3-dimensional cloud-resolving model the System for Atmospheric Modeling (SAM) coupled with an explicit bin microphysics scheme and a radar-lidar simulator. Two possible ice enhancement mechanisms – activation of droplet evaporation residues by condensation-followed-by-freezing and droplet freezing by contact freezing inside-out, are scrutinized by extensive comparisons with aircraft and radar and lidar measurements. The locations of ice initiation associated with each mechanism and the role of ice nuclei (IN) in the evolution of mixed-phase clouds are mainly addressed. Simulations with either mechanism agree well with the in-situ and remote sensing measurements on ice microphysical properties but liquid water content is slightly underpredicted. These two mechanisms give very similar cloud microphysical, macrophysical, dynamical, and radiative properties, although the ice nucleation properties (rate, frequency and location) are completely different. Ice nucleation from activation of evaporation nuclei is most efficient near cloud top areas concentrated on the edges of updrafts, while ice initiation from the drop freezing process has no significant location preference (occurs anywhere that droplet evaporation is significant). Both enhanced nucleation mechanisms contribute dramatically to ice formation with ice particle concentration of 10-15 times higher relative to the simulation without either of them. The contribution of ice nuclei (IN) recycling from ice particle evaporation to IN and ice particle concentration is found to be very significant in this case. Cloud can be very sensitive to IN initially and form a nonquilibrium transition condition, but become much less sensitive as cloud evolves to a steady mixed-phase condition. The parameterization of Meyers et al. [1992] with the observed MPACE IN concentration is able to predict the observed mixed-phase clouds reasonably well. This validation may facilitate the application of this parameterization in the cloud and climate models to simulate Arctic clouds.

Fan, Jiwen; Ovtchinnikov, Mikhail; Comstock, Jennifer M.; McFarlane, Sally A.; Khain, Alexander

2009-02-27T23:59:59.000Z

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


41

Arctic Mixed-Phase Clouds Simulated by a Cloud-Resolving Model: Comparison with ARM Observations and Sensitivity to Microphysics Parameterizations  

Science Conference Proceedings (OSTI)

Single-layer mixed-phase stratiform (MPS) Arctic clouds, which formed under conditions of large surface heat flux combined with general subsidence during a subperiod of the Atmospheric Radiation Measurement (ARM) Program’s Mixed-Phase Arctic ...

Yali Luo; Kuan-Man Xu; Hugh Morrison; Greg McFarquhar

2008-04-01T23:59:59.000Z

42

Arctic Cloud Microphysics Retrievals from Surface-Based Remote Sensors at SHEBA  

Science Conference Proceedings (OSTI)

An operational suite of ground-based, remote sensing retrievals for producing cloud microphysical properties is described, assessed, and applied to 1 yr of observations in the Arctic. All measurements were made in support of the Surface Heat ...

Matthew D. Shupe; Taneil Uttal; Sergey Y. Matrosov

2005-10-01T23:59:59.000Z

43

Remote Sensing of Surface and Cloud Properties in the Arctic from AVHRR Measurements  

Science Conference Proceedings (OSTI)

Algorithms to retrieve cloud optical depth and effective radius in the Arctic using Advanced Very High Resolution Radiometer (AVHRR) data are developed, using a comprehensive radiative transfer model in which the atmosphere is coupled to the ...

W. Han; K. Stamnes; Dan Lubin

1999-07-01T23:59:59.000Z

44

Sensitivity of CAM5-Simulated Arctic Clouds and Radiation to Ice Nucleation Parameterization  

Science Conference Proceedings (OSTI)

Sensitivity of Arctic clouds and radiation in the Community Atmospheric Model, version 5, to the ice nucleation process is examined by testing a new physically based ice nucleation scheme that links the variation of ice nuclei (IN) number ...

Shaocheng Xie; Xiaohong Liu; Chuanfeng Zhao; Yuying Zhang

2013-08-01T23:59:59.000Z

45

Microphysical Properties of Single and Mixed-Phase Arctic Clouds...  

NLE Websites -- All DOE Office Websites (Extended Search)

Abstract A novel new approach to retrieve cloud microphysical properties from mixed-phase clouds is presented. This algorithm retrieves cloud optical depth, ice fraction, and...

46

A New Double-Moment Microphysics Parameterization for Application in Cloud and Climate Models. Part II: Single-Column Modeling of Arctic Clouds  

E-Print Network (OSTI)

of the arctic bound- ary layer, the presence of leads (cracks) in the sea ice surface, the persistence of mixed-phaseA New Double-Moment Microphysics Parameterization for Application in Cloud and Climate Models. Part- dicted cloud boundaries and total cloud fraction compare reasonably well with observations. Cloud phase

Zuidema, Paquita

47

The Tropical Warm Pool International Cloud Experiment  

Science Conference Proceedings (OSTI)

A comprehensive dataset describing tropical cloud systems and their environmental setting and impacts has been collected during the Tropical Warm Pool International Cloud Experiment (TWP-ICE) and Aerosol and Chemical Transport in Tropical ...

Peter T. May; James H. Mather; Geraint Vaughan; Keith N. Bower; Christian Jakob; Greg M. McFarquhar; Gerald G. Mace

2008-05-01T23:59:59.000Z

48

The dependence of ice microphysics on aerosol concentration in arctic mixed-phase stratus clouds during ISDAC and M-PACE  

SciTech Connect

Cloud and aerosol data acquired by the National Research Council of Canada (NRC) Convair-580 aircraft in, above, and below single-layer arctic stratocumulus cloud during the Indirect and Semi-Direct Aerosol Campaign (ISDAC) in April 2008 were used to test three aerosol indirect effects hypothesized to act in mixed-phase clouds: the riming indirect effect, the glaciation indirect effect, and the cold second indirect effect. The data showed a correlation of R= 0.75 between liquid drop number concentration, Nliq, inside cloud and ambient aerosol number concentration NPCASP below cloud. This, combined with increasing liquid water content LWC with height above cloud base and the nearly constant profile of Nliq, suggested that liquid drops were nucleated from aerosol at cloud base. No strong evidence of a riming indirect effect was observed, but a strong correlation of R = 0.69 between ice crystal number concentration Ni and NPCASP above cloud was noted. Increases in ice nuclei (IN) concentration with NPCASP above cloud combined with the subadiabatic LWC profiles suggest possible mixing of IN from cloud top consistent with the glaciation indirect effect. The higher Nice and lower effective radius rel for the more polluted ISDAC cases compared to data collected in cleaner single-layer stratocumulus conditions during the Mixed-Phase Arctic Cloud Experiment is consistent with the operation of the cold second indirect effect. However, more data in a wider variety of meteorological and surface conditions, with greater variations in aerosol forcing, are required to identify the dominant aerosol forcing mechanisms in mixed-phase arctic clouds.

Jackson, Robert C.; McFarquhar, Greg; Korolev, Alexei; Earle, Michael; Liu, Peter S.; Lawson, R. P.; Brooks, Sarah D.; Wolde, Mengistu; Laskin, Alexander; Freer, Matthew

2012-08-14T23:59:59.000Z

49

A Critical Examination of Satellite Cloud Retrieval from AVHRR in the Arctic Using SHEBA Data  

Science Conference Proceedings (OSTI)

This study examines the validity and limitations associated with retrieval of cloud optical depth ? and effective droplet size re in the Arctic from Advanced Very High Resolution Radiometer (AVHRR) channels 2 (0.725–1.10 ?m), 3 (3.55–3.93 ?m), ...

Xiaozhen Xiong; Dan Lubin; Wei Li; Knut Stamnes

2002-12-01T23:59:59.000Z

50

A Critical Review of the Australian Experience in Cloud Seeding  

Science Conference Proceedings (OSTI)

From 1947 to 1994 a number of cloud-seeding experiments were done in Australia based on the static cloud-seeding hypothesis. A critical analysis of these successive cloud-seeding experiments, coupled with microphysical observations of the clouds, ...

Brian F. Ryan; Warren D. King

1997-02-01T23:59:59.000Z

51

Distribution and Validation of Cloud Cover Derived from AVHRR Data Over the Arctic Ocean During the SHEBA Year  

NLE Websites -- All DOE Office Websites (Extended Search)

and Validation of Cloud Cover and Validation of Cloud Cover Derived from AVHRR Data Over the Arctic Ocean During the SHEBA Year P. Minnis National Aeronautics and Space Administration Langley Research Center Hampton, Virginia D. A. Spangenberg and V. Chakrapani Analytical Services and Materials, Inc. Hampton, Virginia Introduction Determination of cloud radiation interactions over large areas of the Arctic is possible only with the use of data from polar orbiting satellites. Cloud detection using satellite data is difficult in the Arctic due to the minimal contrast between clouds and the underlying snow surface in visible and infrared wavelengths. Polar clouds are frequently warmer or at the same brightness temperature as the background surface, complicating cloud detection. The brightness temperature differences between the

52

The Sensitivity of Springtime Arctic Mixed-Phase Stratocumulus Clouds to Surface Layer and Cloud-Top Inversion Layer Moisture Sources  

Science Conference Proceedings (OSTI)

In this study a series of idealized large eddy simulations is used to understand the relative impact of cloud top and subcloud layer sources of moisture on the microphysical-radiative-dynamical feedbacks in an Arctic mixed-phase stratocumulus (...

Amy Solomon; Matthew D. Shupe; Ola Persson; Hugh Morrison; Takanobu Yamaguchi; Peter M. Caldwell; Gijs de Boer

53

Simulating Arctic mixed-phase clouds: Sensitivity to environmental...  

NLE Websites -- All DOE Office Websites (Extended Search)

as well as aggregates to precipitation fluxes and radar reflectivity. Observations of icewater drop size distributions, cloud phase, etc., allow us to constrain model...

54

Mesoscale Modeling of Springtime Arctic Mixed-Phase Stratiform Clouds Using a New Two-Moment Bulk Microphysics Scheme  

Science Conference Proceedings (OSTI)

A new two-moment bulk microphysics scheme is implemented into the polar version of the fifth-generation Pennsylvania State University–NCAR Mesoscale Model (MM5) to simulate arctic mixed-phase boundary layer stratiform clouds observed during ...

H. Morrison; J. O. Pinto

2005-10-01T23:59:59.000Z

55

Arctic Cloud Characteristics as Derived from MODIS, CALIPSO, and CloudSat  

Science Conference Proceedings (OSTI)

The Moderate Resolution Imaging Spectroradiometer (MODIS), Cloud–Aerosol Lidar with Orthogonal Polarization (CALIOP), and CloudSat Cloud Profiling Radar (CPR) set of sensors, all in the Afternoon Constellation (A-Train), has been regarded as among ...

Mark Aaron Chan; Josefino C. Comiso

2013-05-01T23:59:59.000Z

56

The 1990 Valentine's Day Arctic Outbreak. Part I: Mesoscale and Microscale Structure and Evolution of a Colorado Front Range Shallow Upslope Cloud  

Science Conference Proceedings (OSTI)

The mesoscale and microscale structure and evolution of a shallow, upslope cloud is described using observations obtained during the Winter Icing and Storms Project (WISP) and model stimulations. The upslope cloud formed within a shallow arctic ...

Roy M. Rasmussen; Ben C. Bernstein; Masataka Murakami; Greg Stossmeister; Jon Reisner; Boba Stankov

1995-07-01T23:59:59.000Z

57

Short-Term Arctic Cloud Statistics at NSA from the Infrared Cloud...  

NLE Websites -- All DOE Office Websites (Extended Search)

J. A. Shaw and B. Thurairajah Department of Electrical and Computer Engineering Montana State University Bozeman, Montana Introduction The infrared cloud imager (ICI) is a...

58

Small Cloud Particle Shapes in Mixed-Phase Clouds  

Science Conference Proceedings (OSTI)

The shapes of cloud particles with maximum dimensions Dmax between 35 and 60 ?m in mixed-phase clouds were studied using high-resolution particle images collected by a cloud particle imager (CPI) during the Mixed-Phase Arctic Cloud Experiment (M-...

Greg M. McFarquhar; Junshik Um; Robert Jackson

2013-05-01T23:59:59.000Z

59

Representation of Arctic Mixed-Phase clouds and the Wegener-Bergeron-Findeisen Process in Climate Models: Perspectives from a Cloud-Resolving Study  

SciTech Connect

Two types of Arctic mixed-phase clouds observed during the ISDAC and M-PACE field campaigns are simulated using a 3-dimensional cloud-resolving model (CRM) with size-resolved cloud microphysics. The modeled cloud properties agree reasonably well with aircraft measurements and surface-based retrievals. Cloud properties such as the probability density function (PDF) of vertical velocity (w), cloud liquid and ice, the regime of ice growth at the expense of liquid water (i.e., Wegener-Bergeron-Findeisen (WBF) process), and the inherent relationships among cloud properties/processes in the mixed-phase layers are examined to gain insights for improving the representation of the mixed-phase processes in General Circulation Models (GCMs). We find that, the WBF process only occurs in about 50% of the mixed-phase regime with the vast majority occurring in the downdrafts. In updrafts both liquid and ice grow simultaneously. But in GCMs, it is not necessary to treat the WBF process at the subgrid scale. Our CRM results produce a w distribution well represented by a Gaussian normal function, validating, at least for arctic clouds, the subgrid treatment used in GCMs. Our CRM results also support the assumption frequently used in GCMs that mixed phase clouds maintain water vapor very near liquid saturation. A Gamma function with a fixed variance does not accurately represent the subgrid variability of cloud liquid. The PDFs of cloud liquid and cloud ice can be fitted with Gamma functions, and a normal function can be used for total water, but the variance should not be fixed. The relationship between the ice depositional growth rate and cloud ice strongly depends on the capacitance of ice particles. The assumption for the capacitance of ice particles (e.g., 1.0 for spheres) used in GCMs could lead to a large deviation in ice depositional growth. At large sales, the maximum overlap assumption looks appropriate.

Fan, Jiwen; Ghan, Steven J.; Ovchinnikov, Mikhail; Liu, Xiaohong; Rasch, Philip J.; Korolev, Alexei

2011-09-20T23:59:59.000Z

60

Arctic Stratus Cloud Properties and Radiative Forcing Derived from Ground-Based Data Collected at Barrow, Alaska  

Science Conference Proceedings (OSTI)

A record of single-layer and overcast low-level Arctic stratus cloud properties has been generated using data collected from May to September 2000 at the Atmospheric Radiation Measurement (ARM) North Slope of Alaska (NSA) (71.3°N, 156.6°W) site ...

Xiquan Dong; Gerald G. Mace

2003-02-01T23:59:59.000Z

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


61

Polar Stratospheric Cloud Observations in the 2006/07 Arctic Winter by Using an Improved Micropulse Lidar  

Science Conference Proceedings (OSTI)

The potential of a new improved version of micropulse lidar (MPL-4) on polar stratospheric cloud (PSC) detection is evaluated in the Arctic over Ny-Ĺlesund (79°N, 12°E), Norway. The campaign took place from January to February 2007 in the frame ...

Carmen Cordoba-Jabonero; Manuel Gil; Margarita Yela; Marion Maturilli; Roland Neuber

2009-10-01T23:59:59.000Z

62

The Retrieval of Stratus Cloud Droplet Effective Radius with Cloud Radars  

Science Conference Proceedings (OSTI)

In situ samples of cloud droplets by aircraft in Oklahoma in 1997, the Surface Heat Budget of the Arctic Ocean (SHEBA)/First ISCCP Regional Experiment (FIRE)-Arctic Cloud Experiment (ACE) in 1998, and various other locations around the world were ...

Shelby Frisch; Matthew Shupe; Irina Djalalova; Graham Feingold; Michael Poellot

2002-06-01T23:59:59.000Z

63

Experiment to Characterize Tropical Cloud Systems  

SciTech Connect

A major experiment to study tropical convective cloud systems and their impacts will take place around Darwin, Northern Australia in early 2006. The Tropical Warm Pool International Cloud Experiment (TWP-ICE) is a collaboration including the DOE ARM (Atmospheric Radiation Measurement) and ARM-UAV programs, NASA centers, the Australian Bureau of Meteorology, CSIRO, and universities in the USA, Australia, Japan, the UK, and Canada. TWP-ICE will be preceded in November/December 2004 by a collaborating European aircraft campaign involving the EU SCOUT-O3 and UK NERC ACTIVE projects. Detailed atmospheric measurements will be made in the Darwin area through the whole Austral summer, giving unprecedented coverage through the pre-monsoon and monsoon periods.

May, Peter T.; Mather, Jim H.; Jakob, Christian

2005-08-02T23:59:59.000Z

64

The 2004 North Slope of Alaska Arctic Winter Radiometric Experiment  

NLE Websites -- All DOE Office Websites (Extended Search)

2004 North Slope of Alaska 2004 North Slope of Alaska Arctic Winter Radiometric Experiment E. R. Westwater, M. A. Klein, and V. Leuski Cooperative Institute for Research in Environmental Sciences University of Colorado National Oceanic and Atmospheric Administration Environmental Technology Laboratory Boulder, Colorado A. J. Gasiewski, T. Uttal, and D. A. Hazen National Oceanic and Atmospheric Administration Environmental Technology Laboratory Boulder, Colorado D. Cimini Remote Sensing Division, CETEMPS Universita' dell'Aquila L'Aquila, Italy V. Mattioli Dipartimento di Ingegneria Elettronica e dell'Informazione Perugia, Italy B. L. Weber and S. Dowlatshahi Science Technology Corporation Boulder, Colorado J. A. Shaw Department of Electrical and Computer Engineering

65

Factors influencing the microphysics and radiative properties of liquid-dominated Arctic clouds: insight from observations of aerosol and clouds during ISDAC  

SciTech Connect

Aircraft measurements during the Indirect and Semi-Direct Aerosol Campaign (ISDAC) in April 2008 are used to investigate aerosol indirect effects in Arctic clouds. Two aerosol-cloud regimes are considered in this analysis: single-layer stratocumulus cloud with below-cloud aerosol concentrations (N{sub a}) below 300 cm{sup -3} on April 8 and April 26-27 (clean cases); and inhomogeneous layered cloud with N{sub a} > 500 cm{sup -3} below cloud base on April 19-20, concurrent with a biomass burning episode (polluted cases). Vertical profiles through cloud in each regime are used to determine average cloud microphysical and optical properties. Positive correlations between the cloud droplet effective radius (Re) and cloud optical depth ({tau}) are observed for both clean and polluted cases, which are characteristic of optically-thin, non-precipitating clouds. Average Re values for each case are {approx} 6.2 {mu}m, despite significantly higher droplet number concentrations (Nd) in the polluted cases. The apparent independence of Re and Nd simplifies the description of indirect effects, such that {tau} and the cloud albedo (A) can be described by relatively simple functions of the cloud liquid water path. Adiabatic cloud parcel model simulations show that the marked differences in Na between the regimes account largely for differences in droplet activation, but that the properties of precursor aerosol also play a role, particularly for polluted cases where competition for vapour amongst the more numerous particles limits activation to larger and/or more hygroscopic particles. The similarity of Re for clean and polluted cases is attributed to compensating droplet growth processes for different initial droplet size distributions.

Earle, Michael; Liu, Peter S.; Strapp, J. Walter; Zelenyuk, Alla; Imre, D.; McFarquhar, Greg; Shantz, Nicole C.; Leaitch, W. R.

2011-11-04T23:59:59.000Z

66

Ice in Clouds Experiment–Layer Clouds. Part II: Testing Characteristics of Heterogeneous Ice Formation in Lee Wave Clouds  

Science Conference Proceedings (OSTI)

Heterogeneous ice nucleation is a source of uncertainty in models that represent ice clouds. The primary goal of the Ice in Clouds Experiment–Layer Clouds (ICE-L) field campaign was to determine if a link can be demonstrated between ice ...

P. R. Field; A. J. Heymsfield; B. J. Shipway; P. J. DeMott; K. A. Pratt; D. C. Rogers; J. Stith; K. A. Prather

2012-03-01T23:59:59.000Z

67

ARM - Field Campaign - Midlatitude Continental Convective Clouds Experiment  

NLE Websites -- All DOE Office Websites (Extended Search)

Experiment (MC3E) Experiment (MC3E) Campaign Links Science Plan MC3E Website Related Campaigns Midlatitude Continental Convective Clouds Experiment: 2DVD Support 2011.04.22, Schwaller, SGP Midlatitude Continental Convective Clouds Experiment (MC3E): Airborne Instruments 2011.04.22, Poellot, AAF Midlatitude Continental Convective Clouds Experiment (MC3E): Multi-Frequency Profilers 2011.04.22, Williams, SGP Midlatitude Continental Convective Clouds Experiment: Parsivel Disdrometer Support 2011.04.22, Schwaller, SGP Midlatitude Continental Convective Clouds Experiment (MC3E): Inner Domain Thermodynamic Profiling during MC3E 2011.04.22, Turner, SGP Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Midlatitude Continental Convective Clouds Experiment (MC3E)

68

User experience of mobile photo sharing in the cloud  

Science Conference Proceedings (OSTI)

Cloud computing is a new paradigm for how applications and services are designed, implemented and accessed through Internet. In the cloud, the user can access services and his personal data real-time from any device. There are already services available ... Keywords: cloud computing, internet services, photo sharing, user experience

Elina Vartiainen; Kaisa Väänänen-Vainio-Mattila

2010-12-01T23:59:59.000Z

69

A New Look at the Israeli Cloud Seeding Experiments  

Science Conference Proceedings (OSTI)

Two statistical experiments, carried out in Israel, appeared for a time to have provided a unique demonstration of the ability of cloud seeding to increase rainfall. In this paper the authors examine the possibility that both experiments were ...

Arthur L. Rangno; Peter V. Robbs

1995-05-01T23:59:59.000Z

70

Midlatitude Continental Convective Clouds Experiment Science...  

NLE Websites -- All DOE Office Websites (Extended Search)

aircraft will fly above and within the clouds while radar systems scan through the storm from multiple locations. At the same time, additional ground-based instruments will...

71

Magellan: experiences from a Science Cloud  

E-Print Network (OSTI)

computing for science at the Argonne Leadership Computinghow the cloud computing business Argonne NationalLab Argonne, IL model can be used to serve the needs of mid-

Ramakrishnan, Lavanya

2013-01-01T23:59:59.000Z

72

Magellan: experiences from a science cloud  

Science Conference Proceedings (OSTI)

Cloud resources promise to be an avenue to address new categories of scientific applications including data-intensive science applications, on-demand/surge computing, and applications that require customized software environments. However, there is a ... Keywords: cloud computing, mapreduce, programming model, science, virtual machines

Lavanya Ramakrishnan; Piotr T. Zbiegel; Scott Campbell; Rick Bradshaw; Richard Shane Canon; Susan Coghlan; Iwona Sakrejda; Narayan Desai; Tina Declerck; Anping Liu

2011-06-01T23:59:59.000Z

73

Eastern Pacific Emitted Aerosol Cloud Experiment  

Science Conference Proceedings (OSTI)

Aerosol–cloud–radiation interactions are widely held to be the largest single source of uncertainty in climate model projections of future radiative forcing due to increasing anthropogenic emissions. The underlying causes of this uncertainty among modeled ...

Lynn M. Russell; Armin Sorooshian; John H. Seinfeld; Bruce A. Albrecht; Athanasios Nenes; Lars Ahlm; Yi-Chun Chen; Matthew Coggon; Jill S. Craven; Richard C. Flagan; Amanda A. Frossard; Haflidi Jonsson; Eunsil Jung; Jack J. Lin; Andrew R. Metcalf; Robin Modini; Johannes Mülmenstädt; Greg Roberts; Taylor Shingler; Siwon Song; Zhen Wang; Anna Wonaschütz

2013-05-01T23:59:59.000Z

74

Interannual Variations of Arctic Cloud Types in Relation to Sea Ice  

Science Conference Proceedings (OSTI)

Sea ice extent and thickness may be affected by cloud changes, and sea ice changes may in turn impart changes to cloud cover. Different types of clouds have different effects on sea ice. Visual cloud reports from land and ocean regions of the ...

Ryan Eastman; Stephen G. Warren

2010-08-01T23:59:59.000Z

75

Using A-Train Arctic cloud observations to constrain and improve...  

NLE Websites -- All DOE Office Websites (Extended Search)

radiation anomalies to the 2007 Arctic sea ice loss Jennifer E. Kay 1,2 Andrew Gettelman 1 , Tristan L'Ecuyer 2 ,Graeme Stephens 2 , and Chris O'Dell 2 1 National Center for...

76

Arctic mixed-phase cloud properties derived from surface-based sensors at SHEBA  

E-Print Network (OSTI)

Mixed-phase clouds are an understudied component of global cloudiness and are thus poorly represented in models at all scales, which typically partition cloud phase as a function of temperature. The proper partitioning of cloud phase is particularly important considering the unique radiative properties of liquid droplets and ice particles, the impact of phase on precipitation processes, and the sensitivity of phase

M. D. Shupe; S. Y. Matrosov; T. Uttal

2006-01-01T23:59:59.000Z

77

Testing cloud microphysics parameterizations in NCAR CAM5 with ISDAC and M-PACE observations  

E-Print Network (OSTI)

ice nucleation parameterization slightly improves the model performance for low-level mixed-phase ice loss by enhancing ice-albedo feedbacks [Kay et al., 2008]. Arctic clouds are often mixed-phase (i-Direct Aerosol Campaign (ISDAC) and Mixed-Phase Arctic Cloud Experiment (M-PACE), which were conducted at its

78

Atmospheric Radiation Measurement Tropical Warm Pool International Cloud Experiment  

NLE Websites -- All DOE Office Websites (Extended Search)

Tropical Warm Pool Tropical Warm Pool International Cloud Experiment General Description The Tropical Warm Pool - International Cloud Experiment (TWP-ICE) was a collaborative effort led by the U.S. Department of Energy's Atmospheric Radiation Measurement (ARM) Program and the Australian Bureau of Meteorology. Beginning January 21 and ending February 14, 2006, the experiment was conducted in the region near the ARM Climate Research Facility in Darwin, Northern Australia. This permanent facility is fully equipped with sophisticated instruments for measuring cloud and other atmospheric properties to provide a long-term record of continuous observational data. Measurements obtained from the other experiment components (explained below) will complement this dataset to provide a detailed description of the tropical atmosphere.

79

The Influence of Solar Zenith Angle and Cloud Type on Cloud Radiative Forcing at the Surface in the Arctic  

Science Conference Proceedings (OSTI)

Measurements of the long- and shortwave incident radiation taken from the USCGC Polar Sea during a research cruise to the Northeast Water Polynya during the summer of 1993 are analyzed together with observations of cloud type and amount to ...

Peter J. Minnett

1999-01-01T23:59:59.000Z

80

Use of ARM/NSA Data to Validate and Improve the Remote Sensing Retrieval of Cloud and Surface Properties in the Arctic from AVHRR Data  

NLE Websites -- All DOE Office Websites (Extended Search)

ARM/NSA Data to Validate and Improve the ARM/NSA Data to Validate and Improve the Remote Sensing Retrieval of Cloud and Surface Properties in the Arctic from AVHRR Data X. Xiong QSS Group, Inc. National Oceanic and Atmospheric Administration National Environmental Satellite, Data, and Information Service Office of Research and Applications Camp Springs, Maryland R. Storvold and C. Marty Geophysical Institute University of Alaska Fairbanks, Alaska K. H. Stamnes Stevens Institute of Technology Hoboken, New Jersey B. D. Zak Sandia National Laboratories Albuquerque, New Mexico Introduction Clouds in the Arctic have an important impact on the radiative energy balance. However, the effects of clouds still constitute one of the largest uncertainties in the study of climate change. Because the surface

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


81

ARM - Field Campaign - Complex Layered Cloud Experiment (CLEX)  

NLE Websites -- All DOE Office Websites (Extended Search)

govCampaignsComplex Layered Cloud Experiment (CLEX) govCampaignsComplex Layered Cloud Experiment (CLEX) Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Complex Layered Cloud Experiment (CLEX) 1996.06.20 - 1996.07.02 Lead Scientist : Graeme Stephens Data Availability TABLE 1 Locations and Status of Extended Facilitiesa SMOS(c) Comments Site Elevation(b) Latitude, Surface Flux SIROS(c) (m) Longitude Type Station(c) (deg) Larned, KS 632 38.202 N Wheat ECOR Yes Yes Power and communication center EF-1 99.316 W 9/95 9/95 9/95 installation planned for July 1995 Hillsboro, 450 38.306 N Pasture EBBR 8/95 No Yes 8/95 Power and communication center

82

Influence of Humidified Aerosol on Lidar Depolarization Measurements below Ice-Precipitating Arctic Stratus  

Science Conference Proceedings (OSTI)

Lidar measurements obtained during the Surface Heat Budget of the Arctic Ocean (SHEBA) experiment under a mixed-phase stratus cloud that was lightly precipitating ice show a range of surprisingly low depolarization ratios (4%–23%), despite an ...

Bastiaan van Diedenhoven; Ann M. Fridlind; Andrew S. Ackerman

2011-10-01T23:59:59.000Z

83

BNL | Midlatitude Continental Convective Clouds Experiment (MC3E)  

NLE Websites -- All DOE Office Websites (Extended Search)

Midlatitude Continental Convective Clouds Experiment Midlatitude Continental Convective Clouds Experiment Convective processes play a critical role in the Earth's energy balance through the redistribution of heat and moisture in the atmosphere and their link to the hydrological cycle. Accurate representation of convective processes in numerical models is vital towards improving current and future simulations of Earths climate system. Despite improvements in computing power, current operational weather and global climate models are unable to resolve the natural temporal and spatial scales important to convective processes and therefore must turn to parameterization schemes to represent these processes. In turn, parameterization schemes in cloud-resolving models need to be evaluated for their generality and application to a

84

ARM - Field Campaign - Midlatitude Continental Convective Clouds Experiment  

NLE Websites -- All DOE Office Websites (Extended Search)

Experiment Experiment (MC3E): Multi-Frequency Profilers Related Campaigns Midlatitude Continental Convective Clouds Experiment (MC3E) 2011.04.22, Jensen, SGP Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Midlatitude Continental Convective Clouds Experiment (MC3E): Multi-Frequency Profilers 2011.04.22 - 2011.06.06 Lead Scientist : Christopher Williams For data sets, see below. Description The scientific focus was to study the vertical structure of precipitation in a vertical column over the SGP Central Facility. These multi-frequency profiler observations enabled directly measuring the vertical air motion and retrieving the raindrop size distributions from near the surface to just under the freezing level. These profilers were deployed during MC3E

85

Aerosol Effects on Cloud Emissivity and Surface Longwave Heating in the Arctic  

Science Conference Proceedings (OSTI)

Increases in anthropogenic aerosols in the atmosphere tend to increase the reflectance of solar (shortwave) radiation from water clouds, which can lead to lower surface temperatures. Here an opposing effect whereby aerosols increase the longwave ...

Timothy J. Garrett; Lawrence F. Radke; Peter V. Hobbs

2002-02-01T23:59:59.000Z

86

Numerical Simulations of Observed Arctic Stratus Clouds Using a Second-Order Turbulence Closure Model  

Science Conference Proceedings (OSTI)

A high-resolution one-dimensional version of a second-order turbulence closure radiative-convective model, developed at Los Alamos National Laboratory, is used to simulate the interactions among turbulence, radiation, and bulk cloud parameters in ...

W. S. Smith; C-Y. J. Kao

1996-01-01T23:59:59.000Z

87

Simulating mixed-phase Arctic stratus clouds: sensitivity to ice initiation mechanisms  

E-Print Network (OSTI)

M. : Role of a parameterized ice-phase mi- crophysics in anof contact nucleation in ice phase initiation in clouds, J.simulated, process of ice phase initiation due to freezing

Sednev, I.

2008-01-01T23:59:59.000Z

88

Evaluation of an AVHRR Cloud Detection and Classification Method over the Central Arctic Ocean  

Science Conference Proceedings (OSTI)

A cloud classification method that uses both multispectral and textural features with a maximum likelihood discriminator is applied to full-resolution AVHRR (Advanced Very High Resolution Radiometer) data from 100 NOAA polar-orbiter overpasses ...

Dan Lubin; Esther Morrow

1998-02-01T23:59:59.000Z

89

An Improved Parameterization for Simulating Arctic Cloud Amount in the CCSM3 Climate Model  

Science Conference Proceedings (OSTI)

A simple alternative parameterization for predicting cloud fraction in the Community Climate System Model, version 3 (CCSM3) global climate model is presented. This formula, dubbed “freeezedry,” is designed to alleviate the bias of excessive low ...

Steve Vavrus; Duane Waliser

2008-11-01T23:59:59.000Z

90

Assessing the Potential for Rain Augmentation?The Nelspruit Randomized Convective Cloud Seeding Experiment  

Science Conference Proceedings (OSTI)

The experimental design, analyses, and results of the first Nelspruit randomized cloud seeding experiment are described. The experiment ran for three years, commencing in October 1984, and involved the on-top seeding of new cloud turrets growing ...

G. K. Mather; M. J. Dixon; J. M. de Jager

1996-09-01T23:59:59.000Z

91

A Cirrus-Cloud Experiment: Intensive Field Observations Planned for Fire  

Science Conference Proceedings (OSTI)

Plans for an intensive cirrus-cloud field experiment are described. The Cirrus Intensive Field Observations (Citrus IFO) is a major component of the First ISCCP (International Satellite Cloud Climatology Project) Regional Experiment (FIRE). The ...

David O'C. Starr

1987-02-01T23:59:59.000Z

92

Precipitation Features Observed by Doppler Radar at Tuktoyaktuk, Northwest Territories, Canada, during the Beaufort and Arctic Storms Experiment  

Science Conference Proceedings (OSTI)

In the fall of 1994, the Beaufort and Arctic Storms Experiment (BASE) was held to collect information on the structure and evolution of mesoscale weather systems over the southern Beaufort Sea and the Mackenzie River delta of the western Canadian ...

Yoshio Asuma; Soshi Iwata; Katsuhiro Kikuchi; G. W. Kent Moore; Ryuji Kimura; Kazuhisa Tsuboki

1998-09-01T23:59:59.000Z

93

How Well Do Regional Climate Models Reproduce Radiation and Clouds in the Arctic? An Evaluation of ARCMIP Simulations  

Science Conference Proceedings (OSTI)

Downwelling radiation in six regional models from the Arctic Regional Climate Model Intercomparison (ARCMIP) project is systematically biased negative in comparison with observations from the Surface Heat Budget of the Arctic Ocean (SHEBA) ...

Michael Tjernström; Joseph Sedlar; Matthew D. Shupe

2008-09-01T23:59:59.000Z

94

Midlatitude Continental Convective Clouds Experiment (MC3E)  

SciTech Connect

Convective processes play a critical role in the Earth’s energy balance through the redistribution of heat and moisture in the atmosphere and subsequent impacts on the hydrologic cycle. Global observation and accurate representation of these processes in numerical models is vital to improving our current understanding and future simulations of Earth’s climate system. Despite improvements in computing power, current operational weather and global climate models are unable to resolve the natural temporal and spatial scales that are associated with convective and stratiform precipitation processes; therefore, they must turn to parameterization schemes to represent these processes. In turn, the physical basis for these parameterization schemes needs to be evaluated for general application under a variety of atmospheric conditions. Analogously, space-based remote sensing algorithms designed to retrieve related cloud and precipitation information for use in hydrological, climate, and numerical weather prediction applications often rely on physical “parameterizations” that reliably translate indirectly related instrument measurements to the physical quantity of interest (e.g., precipitation rate). Importantly, both spaceborne retrieval algorithms and model convective parameterization schemes traditionally rely on field campaign data sets as a basis for evaluating and improving the physics of their respective approaches. The Midlatitude Continental Convective Clouds Experiment (MC3E) will take place in central Oklahoma during the April–May 2011 period. The experiment is a collaborative effort between the U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Climate Research Facility and the National Aeronautics and Space Administration’s (NASA) Global Precipitation Measurement (GPM) mission Ground Validation (GV) program. The field campaign leverages the unprecedented observing infrastructure currently available in the central United States, combined with an extensive sounding array, remote sensing and in situ aircraft observations, NASA GPM ground validation remote sensors, and new ARM instrumentation purchased with American Recovery and Reinvestment Act funding. The overarching goal is to provide the most complete characterization of convective cloud systems, precipitation, and the environment that has ever been obtained, providing constraints for model cumulus parameterizations and space-based rainfall retrieval algorithms over land that have never before been available. Several different components of convective cloud and precipitation processes tangible to both the convective parameterization and precipitation retrieval algorithm problem are targeted, such as preconvective environment and convective initiation, updraft/downdraft dynamics, condensate transport and detrainment, precipitation and cloud microphysics, spatial and temporal variability of precipitation, influence on the environment and radiation, and a detailed description of the large-scale forcing.

Jensen, MP; Petersen, WA; Del Genio, AD; Giangrande, SE; Heymsfield, A; Heymsfield, G; Hou, AY; Kollias, P; Orr, B; Rutledge, SA; Schwaller, MR; Zipser, E

2010-04-01T23:59:59.000Z

95

ARM - Field Campaign - Ground-based Cloud Tomography Experiment at SGP  

NLE Websites -- All DOE Office Websites (Extended Search)

govCampaignsGround-based Cloud Tomography Experiment at SGP govCampaignsGround-based Cloud Tomography Experiment at SGP Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Ground-based Cloud Tomography Experiment at SGP 2009.05.26 - 2009.07.17 Lead Scientist : Dong Huang For data sets, see below. Description Knowledge of 3D cloud properties is pressingly needed in many research fields. One of the problems encountered when trying to represent 3D cloud fields in numerical models is that the existing techniques cannot provide necessary observations at the required spatial scale and resolution. We tested a new promising technique for measuring 3D cloud microphysical structure, called cloud microwave tomography, at the Southern Great Plains (SGP) site for one month in late April 2009. Five microwave scanning

96

Simulating mixed-phase Arctic stratus clouds: Sensitivity to ice initiation mechanisms  

E-Print Network (OSTI)

M. : Role of a parameterized ice-phase micro- physics in anconcentration (N i ) for ice phase in experiments with icei L ?1 Table 8. Composite ice phase effective radius (R ei )

Sednev, I.

2009-01-01T23:59:59.000Z

97

Experiences with eucalyptus: deploying an open source cloud  

Science Conference Proceedings (OSTI)

With the recent trend of exploiting resources of the cloud, we have embarked on a journey to deploy an open source cloud using Eucalyptus. During the past year we have learned many lessons about the use of Eucalyptus and clouds in general. The area of ...

Rick Bradshaw; Piotr T. Zbiegiel

2010-11-01T23:59:59.000Z

98

Microphysics of Premonsoon and Monsoon Clouds as Seen from In Situ Measurements during the Cloud Aerosol Interaction and Precipitation Enhancement Experiment (CAIPEEX)  

Science Conference Proceedings (OSTI)

Analysis of the microphysical structure of deep convective clouds using in situ measurements during the Cloud Aerosol Interaction and Precipitation Enhancement Experiment (CAIPEEX) over the Indian peninsular region is presented. It is shown that ...

Thara V. Prabha; A. Khain; R. S. Maheshkumar; G. Pandithurai; J. R. Kulkarni; M. Konwar; B. N. Goswami

2011-09-01T23:59:59.000Z

99

Factors Influencing Simulated Changes in Future Arctic Cloudiness  

Science Conference Proceedings (OSTI)

This study diagnoses the changes in Arctic clouds simulated by the Community Climate System Model version 3 (CCSM3) in a transient 2 × CO2 simulation. Four experiments—one fully coupled and three with prescribed SSTs and/or sea ice cover—are used ...

Stephen J. Vavrus; Uma S. Bhatt; Vladimir A. Alexeev

2011-09-01T23:59:59.000Z

100

Arctic Surface, Cloud, and Radiation Properties Based on the AVHRR Polar Pathfinder Dataset. Part I: Spatial and Temporal Characteristics  

Science Conference Proceedings (OSTI)

With broad spectral coverage and high spatial and temporal resolutions, satellite sensors can provide the data needed for the analysis of spatial and temporal variations of climate parameters in data-sparse regions such as the Arctic and ...

Xuanji Wang; Jeffrey R. Key

2005-07-01T23:59:59.000Z

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


101

Analysis of Radiosonde and Ground-Based Remotely Sensed PWV Data from the 2004 North Slope of Alaska Arctic Winter Radiometric Experiment  

Science Conference Proceedings (OSTI)

During 9 March–9 April 2004, the North Slope of Alaska Arctic Winter Radiometric Experiment was conducted at the Atmospheric Radiation Measurement Program’s (ARM) “Great White” field site near Barrow, Alaska. The major goals of the experiment ...

V. Mattioli; E. R. Westwater; D. Cimini; J. C. Liljegren; B. M. Lesht; S. I. Gutman; F. J. Schmidlin

2007-03-01T23:59:59.000Z

102

Tropical Warm Pool International Cloud Experiment (TWP-ICE): Cloud and Rain Characteristics in the Australian Monsoon  

SciTech Connect

The impact of oceanic convection on its environment and the relationship between the characteristics of the convection and the resulting cirrus characteristics is still not understood. An intense airborne measurement campaign combined with an extensive network of ground-based observations is being planned for the region near Darwin, Northern Australia, during January-February, 2006, to address these questions. The Tropical Warm Pool – International Cloud Experiment (TWP-ICE) will be the first field program in the tropics that attempts to describe the evolution of tropical convection, including the large scale heat, moisture, and momentum budgets, while at the same time obtaining detailed observations of cloud properties and the impact of the clouds on the environment. The emphasis will be on cirrus for the cloud properties component of the experiment. Cirrus clouds are ubiquitous in the tropics and have a large impact on their environment but the properties of these clouds are poorly understood. A crucial product from this experiment will be a dataset suitable to provide the forcing and testing required by cloud-resolving models and parameterizations in global climate models. This dataset will provide the necessary link between cloud properties and the models that are attempting to simulate them. The experiment is a collaboration between the U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Program, the Bureau of Meteorology (BoM), the National Aeronautics and Space Administration (NASA), the European Commission DG RTD-1.2, and several United States, Australian, Canadian, and European Universities. This experiment will be undertaken over a 4-week period in early 2006. January and February corresponds to the wet phase of the Australia monsoon. This season has been selected because, despite Darwin’s coastal location, the convection that occurs over and near Darwin at this time is largely of maritime origin with a large fetch over water. Based on previous experiments, the convection appears typical of maritime convection with widespread convection that has complex organization, but is not as deep or as intense as continental or coastal convection. Therefore, it is expected that the convection and cloud characteristics will be representative of conditions typical for wide areas of the tropics.

PT May; C Jakob; JH Mather

2004-05-30T23:59:59.000Z

103

ARM - Field Campaign - WB57 Midlatitude Cirrus Cloud Experiment...  

NLE Websites -- All DOE Office Websites (Extended Search)

invested considerable effort in characterizing clouds with instruments ranging from passive remote sensors on board the EOS platforms, to active remote sensors on Cloudsat and...

104

Numerical Simulation of Dry Ice Cloud Seeding Experiments  

Science Conference Proceedings (OSTI)

The application of a two-dimensional, time-dependent cloud model to describe the effects of dry ice cloud seeding is demonstrated. A conservation equation and associated auxiliary equations for the mixing ratio of dry ice (CO2) are presented. The ...

Fred J. Kopp; Harold D. Orville; Richard D. Farley; John H. Hirsch

1983-09-01T23:59:59.000Z

105

An Automatic Recording Raingage Network for a Cloud-Seeding Experiment  

Science Conference Proceedings (OSTI)

The CSIRO Division of Cloud Physics has designed and built 103 automatic recording raingages, at a cost of about $US600 each, for use in a cloud-seeding experiment. Each unit consists of a siphoned tipping bucket interfaced to a monophonic ...

D. A. Parkin; W. D. King; D. E. Shaw

1982-02-01T23:59:59.000Z

106

ARM - Publications: Science Team Meeting Documents: An Arctic Springtime  

NLE Websites -- All DOE Office Websites (Extended Search)

An Arctic Springtime Mixed-Phase Cloudy Boundary Layer observed during An Arctic Springtime Mixed-Phase Cloudy Boundary Layer observed during SHEBA Zuidema, Paquita RSMAS/MPO University of Miami Han, Yong NASA Goddard Space Flight Center Intrieri, Janet NOAA/Environmental Technology Laboratory Key, Jeffrey Boston University Lawson, Paul SPEC Inc. Matrosov, Sergey NOAA/Environmental Technology Laboratory Shupe, Matthew CIRES/NOAA/ETL Uttal, Taneil NOAA/Environmental Technology Laboratory The microphysical characteristics, radiative impact, and lifecycle of a long-lived, surface-based mixed-layer, mixed-phase cloud with an average temperature of approximately -20 C are presented and discussed. The cloud was observed during the Surface Heat Budget of the Arctic experiment from May 1 through May 10, 1998. Vertically-resolved properties of the liquid

107

Ice in Clouds Experiment—Layer Clouds. Part I: Ice Growth Rates Derived from Lenticular Wave Cloud Penetrations  

Science Conference Proceedings (OSTI)

Lenticular wave clouds are used as a natural laboratory to estimate the linear and mass growth rates of ice particles at temperatures from ?20° to ?32°C and to characterize the apparent rate of ice nucleation at water saturation at a nearly ...

Andrew J. Heymsfield; Paul R. Field; Matt Bailey; Dave Rogers; Jeffrey Stith; Cynthia Twohy; Zhien Wang; Samuel Haimov

2011-11-01T23:59:59.000Z

108

Results of On-Top Glaciogenic Cloud Seeding in Thailand. Part I: The Demonstration Experiment  

Science Conference Proceedings (OSTI)

Randomized, cold-cloud, rain-enhancement experiments were carried out during 1991–98 in the Bhumibol catchment area in northwestern Thailand. Exploratory experimentation in 1991 and 1993 suggested increases in rainfall from seeding. A ...

William L. Woodley; Daniel Rosenfeld; Bernard A. Silverman

2003-07-01T23:59:59.000Z

109

Tests for Persistent Effects of Cloud Seeding in a Recent Australian Experiment  

Science Conference Proceedings (OSTI)

An analysis of cloud seeding experiments in Australia prior to 1984 that used silver iodide dispensed from aircraft as the seeding agent suggested that there were systematic aftereffects of seeding at least one month after a given seeded day, as ...

E. K. Bigg

1995-11-01T23:59:59.000Z

110

STORMTIPE: A Forecasting Experiment Using a Three-Dimensional Cloud Model  

Science Conference Proceedings (OSTI)

An experiment using a three-dimensional cloud-scale numerical model in an operational forecasting environment was carried out in the spring of 1991. It involved meteorologists generating forecast environmental conditions associated with ...

Harold E. Brooks; Charles A. Doswell III; Louis J. Wicker

1993-09-01T23:59:59.000Z

111

Summer Cumulus Cloud Seeding Experiments near Yellowknife and Thunder Bay, Canada  

Science Conference Proceedings (OSTI)

A summer (June and July) cumulus cloud seeding experiment was conducted in Canada near Yellowknife in 1975 and 1976, and Thunder Bay in 1977 and 1978. Microphysical and dynamical measurements were made with three instrumented aircraft, flying in ...

G. A. Isaac; J. W. Strapp; R. S. Schemenauer; J. I. Macpherson

1982-09-01T23:59:59.000Z

112

Clouds  

NLE Websites -- All DOE Office Websites (Extended Search)

heated by the sun, produces rising columns of air in which the moisture condenses into tall fleecy white clouds At night, when the sky is clear, the earth cools to give those...

113

Anvil Characteristics as Seen by C-POL during the Tropical Warm Pool International Cloud Experiment (TWP-ICE)  

Science Conference Proceedings (OSTI)

The Tropical Pacific Warm Pool International Cloud Experiment (TWP-ICE) took place in Darwin, Australia, in early 2006. C-band radar data were used to characterize tropical anvil (i.e., thick, nonprecipitating cloud associated with deep ...

Kaycee Frederick; Courtney Schumacher

2008-01-01T23:59:59.000Z

114

Estimations of Cloud Optical Thickness from Ground-Based Measurements of Incoming Solar Radiation in the Arctic  

Science Conference Proceedings (OSTI)

A technique for evaluation of cloud optical thickness (plant-parallel, homogeneous layer) from ground-based measurements of incoming solar irradiance using a simple radiation model is introduced. The sensitivities of downward and upward fluxes of ...

E. Leontyeva; K. Stamnes

1994-04-01T23:59:59.000Z

115

8, 1175511819, 2008 mixed-phase Arctic  

E-Print Network (OSTI)

, process of ice phase initiation due to freezing of25 supercooled water in both saturatedACPD 8, 11755­11819, 2008 Simulating mixed-phase Arctic stratus clouds I. Sednev et al. Title Page.0 License. Atmospheric Chemistry and Physics Discussions Simulating mixed-phase Arctic stratus clouds

Paris-Sud XI, Université de

116

Parameterization of the Extinction Coefficient in Ice and Mixed-Phase Arctic Clouds during the ISDAC Field Campaign  

SciTech Connect

This report documents the history of attempts to directly measure cloud extinction, the current measurement device known as the Cloud Extinction Probe (CEP), specific problems with direct measurement of extinction coefficient, and the attempts made here to address these problems. Extinction coefficient is one of the fundamental microphysical parameters characterizing bulk properties of clouds. Knowledge of extinction coefficient is of crucial importance for radiative transfer calculations in weather prediction and climate models given that Earth's radiation budget (ERB) is modulated much by clouds. In order for a large-scale model to properly account for ERB and perturbations to it, it must ultimately be able to simulate cloud extinction coefficient well. In turn this requires adequate and simultaneous simulation of profiles of cloud water content and particle habit and size. Similarly, remote inference of cloud properties requires assumptions to be made about cloud phase and associated single-scattering properties, of which extinction coefficient is crucial. Hence, extinction coefficient plays an important role in both application and validation of methods for remote inference of cloud properties from data obtained from both satellite and surface sensors (e.g., Barker et al. 2008). While estimation of extinction coefficient within large-scale models is relatively straightforward for pure water droplets, thanks to Mie theory, mixed-phase and ice clouds still present problems. This is because of the myriad forms and sizes that crystals can achieve, each having their own unique extinction properties. For the foreseeable future, large-scale models will have to be content with diagnostic parametrization of crystal size and type. However, before they are able to provide satisfactory values needed for calculation of radiative transfer, they require the intermediate step of assigning single-scattering properties to particles. The most basic of these is extinction coefficient, yet it is rarely measured directly, and therefore verification of parametrizations is difficult. The obvious solution is to be able to measure microphysical properties and extinction at the same time and for the same volume. This is best done by in situ sampling by instruments mounted on either balloon or aircraft. The latter is the usual route and the one employed here. Yet the problem of actually measuring extinction coefficient directly for arbitrarily complicated particles still remains unsolved.

Korolev, A; Shashkov, A; Barker, H

2012-03-06T23:59:59.000Z

117

Parameterization of the Extinction Coefficient in Ice and Mixed-Phase Arctic Clouds during the ISDAC Field Campaign  

SciTech Connect

This report documents the history of attempts to directly measure cloud extinction, the current measurement device known as the Cloud Extinction Probe (CEP), specific problems with direct measurement of extinction coefficient, and the attempts made here to address these problems. Extinction coefficient is one of the fundamental microphysical parameters characterizing bulk properties of clouds. Knowledge of extinction coefficient is of crucial importance for radiative transfer calculations in weather prediction and climate models given that Earth's radiation budget (ERB) is modulated much by clouds. In order for a large-scale model to properly account for ERB and perturbations to it, it must ultimately be able to simulate cloud extinction coefficient well. In turn this requires adequate and simultaneous simulation of profiles of cloud water content and particle habit and size. Similarly, remote inference of cloud properties requires assumptions to be made about cloud phase and associated single-scattering properties, of which extinction coefficient is crucial. Hence, extinction coefficient plays an important role in both application and validation of methods for remote inference of cloud properties from data obtained from both satellite and surface sensors (e.g., Barker et al. 2008). While estimation of extinction coefficient within large-scale models is relatively straightforward for pure water droplets, thanks to Mie theory, mixed-phase and ice clouds still present problems. This is because of the myriad forms and sizes that crystals can achieve, each having their own unique extinction properties. For the foreseeable future, large-scale models will have to be content with diagnostic parametrization of crystal size and type. However, before they are able to provide satisfactory values needed for calculation of radiative transfer, they require the intermediate step of assigning single-scattering properties to particles. The most basic of these is extinction coefficient, yet it is rarely measured directly, and therefore verification of parametrizations is difficult. The obvious solution is to be able to measure microphysical properties and extinction at the same time and for the same volume. This is best done by in situ sampling by instruments mounted on either balloon or aircraft. The latter is the usual route and the one employed here. Yet the problem of actually measuring extinction coefficient directly for arbitrarily complicated particles still remains unsolved.

Korolev, A; Shashkov, A; Barker, H

2012-03-06T23:59:59.000Z

118

Mixed-Phase Arctic Cloud Experiment (M-PACE): the Field Campaign  

DOE Data Explorer (OSTI)

This case study presents data from 27 Sep 2004 to 22 Oct 2004 and covers a region from 65N to 75N latitude and from 160W to 145W longitude.

119

Testing Cloud Microphysics Parameterizations in NCAR CAM5 with ISDAC and M-PACE Observations  

SciTech Connect

Arctic clouds simulated by the NCAR Community Atmospheric Model version 5 (CAM5) are evaluated with observations from the U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Indirect and Semi-Direct Aerosol Campaign (ISDAC) and Mixed-Phase Arctic Cloud Experiment (M-PACE), which were conducted at its North Slope of Alaska site in April 2008 and October 2004, respectively. Model forecasts for the Arctic Spring and Fall seasons performed under the Cloud- Associated Parameterizations Testbed (CAPT) framework generally reproduce the spatial distributions of cloud fraction for single-layer boundary layer mixed-phase stratocumulus, and multilayer or deep frontal clouds. However, for low-level clouds, the model significantly underestimates the observed cloud liquid water content in both seasons and cloud fraction in the Spring season. As a result, CAM5 significantly underestimates the surface downward longwave (LW) radiative fluxes by 20-40 W m-2. The model with a new ice nucleation parameterization moderately improves the model simulations by increasing cloud liquid water content in mixed-phase clouds through the reduction of the conversion rate from cloud liquid to ice by the Wegener-Bergeron- Findeisen (WBF) process. The CAM5 single column model testing shows that change in the homogeneous freezing temperature of rain to form snow from -5 C to -40 C has a substantial impact on the modeled liquid water content through the slowing-down of liquid and rain-related processes. In contrast, collections of cloud ice by snow and cloud liquid by rain are of minor importance for single-layer boundary layer mixed-phase clouds in the Arctic.

Liu, Xiaohong; Xie, Shaocheng; Boyle, James; Klein, Stephen A.; Shi, Xiangjun; Wang, Zhien; Lin, Wuyin; Ghan, Steven J.; Earle, Michael; Liu, Peter; Zelenyuk, Alla

2011-12-24T23:59:59.000Z

120

Testing cloud microphysics parameterizations in NCAR CAM5 with ISDAC and M-PACE observations  

SciTech Connect

Arctic clouds simulated by the National Center for Atmospheric Research (NCAR) Community Atmospheric Model version 5 (CAM5) are evaluated with observations from the U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Indirect and Semi-Direct Aerosol Campaign (ISDAC) and Mixed-Phase Arctic Cloud Experiment (M-PACE), which were conducted at its North Slope of Alaska site in April 2008 and October 2004, respectively. Model forecasts for the Arctic spring and fall seasons performed under the Cloud-Associated Parameterizations Testbed framework generally reproduce the spatial distributions of cloud fraction for single-layer boundary-layer mixed-phase stratocumulus and multilayer or deep frontal clouds. However, for low-level stratocumulus, the model significantly underestimates the observed cloud liquid water content in both seasons. As a result, CAM5 significantly underestimates the surface downward longwave radiative fluxes by 20-40 W m{sup -2}. Introducing a new ice nucleation parameterization slightly improves the model performance for low-level mixed-phase clouds by increasing cloud liquid water content through the reduction of the conversion rate from cloud liquid to ice by the Wegener-Bergeron-Findeisen process. The CAM5 single-column model testing shows that changing the instantaneous freezing temperature of rain to form snow from -5 C to -40 C causes a large increase in modeled cloud liquid water content through the slowing down of cloud liquid and rain-related processes (e.g., autoconversion of cloud liquid to rain). The underestimation of aerosol concentrations in CAM5 in the Arctic also plays an important role in the low bias of cloud liquid water in the single-layer mixed-phase clouds. In addition, numerical issues related to the coupling of model physics and time stepping in CAM5 are responsible for the model biases and will be explored in future studies.

Liu X.; Lin W.; Xie, S.; Boyle, J.; Klein, S. A.; Shi, X.; Wang, Z.; Ghan, S. J.; Earle, M.; Liu, P. S. K.; Zelenyuk, A.

2011-12-24T23:59:59.000Z

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


121

Experiments in Shower-Top Forecasting Using an Interactive One-Dimensional Cloud Model  

Science Conference Proceedings (OSTI)

Experiments were made in prediction of the elevation of warm season shower-tops, both prevailing and highest, using a one-dimensional cloud model run on a real-time minicomputer system. A forecaster inter-actively altered the initial temperatures ...

Timothy D. Crum; John J. Cahir

1983-04-01T23:59:59.000Z

122

Evaluation of the Bridger Range Winter Cloud Seeding Experiment Using Control Gages  

Science Conference Proceedings (OSTI)

A randomized exploratory single-area cloud seeding experiment was carried out in the Bridger Range of southwestern Montana during the winters of 1969–72. Seeding was accomplished using ground-based silver iodide (AgI) generators located more than ...

Arlin B. Super; James A. Heimbach Jr.

1983-12-01T23:59:59.000Z

123

Cloud Droplet Residual Particle Microphysics in Marine Stratocumulus Clouds Observed during the Monterey Area Ship Track Experiment  

Science Conference Proceedings (OSTI)

The effect of marine boundary layer pollution level (as determined by the aerosol particle number concentration) on the size distribution of aerosol particles that formed cloud droplets in marine stratiform clouds is examined. In situ ...

Elisabeth Öström; Kevin J. Noone; Robert A. Pockalny

2000-08-01T23:59:59.000Z

124

Response of Upper Clouds in Global Warming Experiments Obtained Using a Global Nonhydrostatic Model with Explicit Cloud Processes  

Science Conference Proceedings (OSTI)

Using a global nonhydrostatic model with explicit cloud processes, upper-cloud changes are investigated by comparing the present climate condition under the perpetual July setting and the global warming condition, in which the sea surface ...

Masaki Satoh; Shin-ichi Iga; Hirofumi Tomita; Yoko Tsushima; Akira T. Noda

2012-03-01T23:59:59.000Z

125

Cloud-Resolving Modeling of Tropical Cloud Systems during Phase III of GATE. Part I: Two-Dimensional Experiments  

Science Conference Proceedings (OSTI)

A formal framework is established for the way in which cloud-resolving numerical models are used to investigate the role of precipitating cloud systems in climate and weather forecasting models. Emphasis is on models with periodic lateral ...

Wojciech W. Grabowski; Xiaoqing Wu; Mitchell W. Moncrieff

1996-12-01T23:59:59.000Z

126

Simulations of Arctic mixed-phase clouds using a new aerosol-linked ice nuclei parameterization in a prognostic ice prediction scheme.  

E-Print Network (OSTI)

??Despite the nearly universally-accepted notion that the Arctic is one of the most important areas to fully understand in the face of a changing global… (more)

Carpenter, James Michael

2013-01-01T23:59:59.000Z

127

Using Doppler spectra to separate hydrometeor populations and analyze ice precipitation in multilayered mixed-phase clouds  

SciTech Connect

Multimodality of cloud radar Doppler spectra is used to partition cloud particle phases and to separate distinct ice populations in the radar sample volume, thereby facilitating analysis of individual ice showers in multilayered mixed-phase clouds. A 35-GHz cloud radar located at Barrow, Alaska, during the Mixed-Phase Arctic Cloud Experiment collected the Doppler spectra. Data from a pair of collocated depolarization lidars confirmed the presence of two liquid cloud layers reported in this study. Surprisingly, both of these cloud layers were embedded in ice precipitation yet maintained their liquid. Our spectral separation of the ice precipitation yielded two distinct ice populations: ice initiated within the two liquid cloud layers and ice precipitation formed in higher cloud layers. Comparisons of ice fall velocity versus radar reflectivity relationships derived for distinct showers reveal that a single relationship might not properly represent the ice showers during this period.

Rambukkange, Mahlon P.; Verlinde, J.; Eloranta, E. W.; Flynn, Connor J.; Clothiaux, Eugene E.

2011-01-31T23:59:59.000Z

128

STORMVEX: The Storm Peak Lab Cloud Property Validation Experiment Science and Operations Plan  

Science Conference Proceedings (OSTI)

During the Storm Peak Lab Cloud Property Validation Experiment (STORMVEX), a substantial correlative data set of remote sensing observations and direct in situ measurements from fixed and airborne platforms will be created in a winter season, mountainous environment. This will be accomplished by combining mountaintop observations at Storm Peak Laboratory and the airborne National Science Foundation-supported Colorado Airborne Multi-Phase Cloud Study campaign with collocated measurements from the second ARM Mobile Facility (AMF2). We describe in this document the operational plans and motivating science for this experiment, which includes deployment of AMF2 to Steamboat Springs, Colorado. The intensive STORMVEX field phase will begin nominally on 1 November 2010 and extend to approximately early April 2011.

Mace, J; Matrosov, S; Shupe, M; Lawson, P; Hallar, G; McCubbin, I; Marchand, R; Orr, B; Coulter, R; Sedlacek, A; Avallone, L; Long, C

2010-09-29T23:59:59.000Z

129

EXPERIENCE IN REDUCING ELECTRON CLOUD AND DYNAMIC PRESSURE RISE IN WARM AND COLD REGIONS IN RHIC.  

SciTech Connect

The large scale application of non-evaporable getter coating in RHIC has been effective in reducing the electron cloud. Since beams with higher intensity and smaller bunch spacing became possible in operation, the emittance growth is of concern. Study results are reported together with experiences of machine improvements: saturated NEG coatings, anti-grazing ridges in warm sections, and the pre-pumping in cryogenic regions.

ZHANG, S.Y.; AHRENS,L.; ALLESI, J.; BAI, M.; BLASKIEWICZ, M.; CAMERON, P.; CONNOLLY, R.; DREES, A.; FISCHER, W.; GULLOTTA, J.; HE, P.; HSEUH, H.C.; HUANG, H.; LEE, R.; LITVINENKO, V.; MACKAY, W.W.; MONTAG, C.; NICOLETTI, A.; OERTER, B.; PILAT, F.; PTITSYN, V.; ROSER, T.; SATOGATA, T.; SMART, L.; SYNDSTRUP, L.; TEPIKIAN, S.; THIEBERGER, P.; TRBOJEVIC, D.; WEI, J.; ZENO, K.

2006-06-23T23:59:59.000Z

130

Numerical Experiments on the Dynamics of the Cloud–Environment Interface: Small Cumulus in a Shear-Free Environment  

Science Conference Proceedings (OSTI)

We report herein high resolution two-dimensional numerical experiments on the dynamics of the mixing between the environment and a small cumulus cloud in the absence of shear. The current paper extends the work of Klaassen and Clark. Serious ...

Wojciech W. Grabowski

1989-12-01T23:59:59.000Z

131

Arctic Mixed-Phase Cloud Properties Derived from Surface-Based Sensors at SHEBA MATTHEW D. SHUPE AND SERGEY Y. MATROSOV  

E-Print Network (OSTI)

, cloud-top liquid layer from which ice particles formed and fell, although deep, multilayered mixed-phase. These values are all larger than those found in single-phase ice clouds at SHEBA. Vertically resolved cloud phases can coexist is in question. A re- view of model parameterizations shows the lower tem- perature

Shupe, Matthew

132

ARM - PI Product - Cloud-Scale Vertical Velocity and Turbulent Dissipation  

NLE Websites -- All DOE Office Websites (Extended Search)

ProductsCloud-Scale Vertical Velocity and Turbulent ProductsCloud-Scale Vertical Velocity and Turbulent Dissipation Rate Retrievals Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send PI Product : Cloud-Scale Vertical Velocity and Turbulent Dissipation Rate Retrievals Site(s) NSA General Description Time-height fields of retrieved in-cloud vertical wind velocity and turbulent dissipation rate, both retrieved primarily from vertically-pointing, Ka-band cloud radar measurements. Files are available for manually-selected, stratiform, mixed-phase cloud cases observed at the North Slope of Alaska (NSA) site during periods covering the Mixed-Phase Arctic Cloud Experiment (MPACE, late September through early November 2004) and the Indirect and Semi-Direct Aerosol Campaign (ISDAC, April-early May

133

Review of science issues, deployment strategy, and status for the ARM north slope of Alaska-Adjacent Arctic Ocean climate research site  

SciTech Connect

Recent climate modeling results point to the Arctic as a region that is particularly sensitive to global climate change. The Arctic warming predicted by the models to result from the expected doubling of atmospheric carbon dioxide is two to three times the predicted mean global warming, and considerably greater than the warming predicted for the Antarctic. The North Slope of Alaska-Adjacent Arctic Ocean (NSA-AAO) Cloud and Radiation Testbed (CART) site of the Atmospheric Radiation Measurement (ARM) Program is designed to collect data on temperature-ice-albedo and water vapor-cloud-radiation feedbacks, which are believed to be important to the predicted enhanced warming in the Arctic. The most important scientific issues of Arctic, as well as global, significance to be addressed at the NSA-AAO CART site are discussed, and a brief overview of the current approach toward, and status of, site development is provided. ARM radiometric and remote sensing instrumentation is already deployed and taking data in the perennial Arctic ice pack as part of the SHEBA (Surface Heat Budget of the Arctic ocean) experiment. In parallel with ARM`s participation in SHEBA, the NSA-AAO facility near Barrow was formally dedicated on 1 July 1997 and began routine data collection early in 1998. This schedule permits the US Department of Energy`s ARM Program, NASA`s Arctic Cloud program, and the SHEBA program (funded primarily by the National Science Foundation and the Office of Naval Research) to be mutually supportive. In addition, location of the NSA-AAO Barrow facility on National Oceanic and Atmospheric Administration land immediately adjacent to its Climate Monitoring and Diagnostic Laboratory Barrow Observatory includes NOAA in this major interagency Arctic collaboration.

Stamnes, K. [Univ. of Alaska, Fairbanks, AK (United States). Geophysical Inst.; Ellingson, R.G. [Univ. of Maryland, College Park, MD (United States). Dept. of Meteorology; Curry, J.A. [Univ. of Colorado, Boulder, CO (United States). Dept. of Aerospace and Engineering Sciences; Walsh, J.E. [Univ. of Illinois, Urbana, IL (United States). Dept. of Atmospheric Sciences; Zak, B.D. [Sandia National Labs., Albuquerque, NM (United States)

1999-01-01T23:59:59.000Z

134

Parameterizing Size Distribution in Ice Clouds  

SciTech Connect

PARAMETERIZING SIZE DISTRIBUTIONS IN ICE CLOUDS David L. Mitchell and Daniel H. DeSlover ABSTRACT An outstanding problem that contributes considerable uncertainty to Global Climate Model (GCM) predictions of future climate is the characterization of ice particle sizes in cirrus clouds. Recent parameterizations of ice cloud effective diameter differ by a factor of three, which, for overcast conditions, often translate to changes in outgoing longwave radiation (OLR) of 55 W m-2 or more. Much of this uncertainty in cirrus particle sizes is related to the problem of ice particle shattering during in situ sampling of the ice particle size distribution (PSD). Ice particles often shatter into many smaller ice fragments upon collision with the rim of the probe inlet tube. These small ice artifacts are counted as real ice crystals, resulting in anomalously high concentrations of small ice crystals (D < 100 µm) and underestimates of the mean and effective size of the PSD. Half of the cirrus cloud optical depth calculated from these in situ measurements can be due to this shattering phenomenon. Another challenge is the determination of ice and liquid water amounts in mixed phase clouds. Mixed phase clouds in the Arctic contain mostly liquid water, and the presence of ice is important for determining their lifecycle. Colder high clouds between -20 and -36 oC may also be mixed phase but in this case their condensate is mostly ice with low levels of liquid water. Rather than affecting their lifecycle, the presence of liquid dramatically affects the cloud optical properties, which affects cloud-climate feedback processes in GCMs. This project has made advancements in solving both of these problems. Regarding the first problem, PSD in ice clouds are uncertain due to the inability to reliably measure the concentrations of the smallest crystals (D < 100 µm), known as the “small mode”. Rather than using in situ probe measurements aboard aircraft, we employed a treatment of ice cloud optical properties formulated in terms of PSD parameters in combination with remote measurements of thermal radiances to characterize the small mode. This is possible since the absorption efficiency (Qabs) of small mode crystals is larger at 12 µm wavelength relative to 11 µm wavelength due to the process of wave resonance or photon tunneling more active at 12 µm. This makes the 12/11 µm absorption optical depth ratio (or equivalently the 12/11 µm Qabs ratio) a means for detecting the relative concentration of small ice particles in cirrus. Using this principle, this project tested and developed PSD schemes that can help characterize cirrus clouds at each of the three ARM sites: SGP, NSA and TWP. This was the main effort of this project. These PSD schemes and ice sedimentation velocities predicted from them have been used to test the new cirrus microphysics parameterization in the GCM known as the Community Climate Systems Model (CCSM) as part of an ongoing collaboration with NCAR. Regarding the second problem, we developed and did preliminary testing on a passive thermal method for retrieving the total water path (TWP) of Arctic mixed phase clouds where TWPs are often in the range of 20 to 130 g m-2 (difficult for microwave radiometers to accurately measure). We also developed a new radar method for retrieving the cloud ice water content (IWC), which can be vertically integrated to yield the ice water path (IWP). These techniques were combined to determine the IWP and liquid water path (LWP) in Arctic clouds, and hence the fraction of ice and liquid water. We have tested this approach using a case study from the ARM field campaign called M-PACE (Mixed-Phase Arctic Cloud Experiment). This research led to a new satellite remote sensing method that appears promising for detecting low levels of liquid water in high clouds typically between -20 and -36 oC. We hope to develop this method in future research.

DeSlover, Daniel; Mitchell, David L.

2009-09-25T23:59:59.000Z

135

Clouds and the Earth's Radiant Energy System (CERES): An Earth Observing System Experiment  

Science Conference Proceedings (OSTI)

Clouds and the Earth's Radiant Energy System (CERES) is an investigation to examine the role of cloud/radiation feedback in the Earth's climate system. The CERES broadband scanning radiometers are an improved version of the Earth Radiation Budget ...

Bruce A. Wielicki; Bruce R. Barkstrom; Edwin F. Harrison; Robert B. Lee III; G. Louis Smith; John E. Cooper

1996-05-01T23:59:59.000Z

136

Retrieval of Thermodynamic Variables within Deep Convective Clouds: Experiments in Three Dimensions  

Science Conference Proceedings (OSTI)

A three-dimensional thermodynamic retrieval method has been developed and tested for application to deep convective clouds. To test the accuracy of the method and for sensitivity studies, output from a three-dimensional numerical cloud model has ...

Carl E. Hane; Robert B. Wilhelmson; Tzvi Gal-Chen

1981-03-01T23:59:59.000Z

137

Evaluation of Mixed-Phase Cloud Microphysics Parameterizations with the NCAR Single Column Climate Model (SCAM) and ARM Observations  

SciTech Connect

Mixed-phase stratus clouds are ubiquitous in the Arctic and play an important role in climate in this region. However, climate models have generally proven unsuccessful at simulating the partitioning of condensed water into liquid droplets and ice crystals in these Arctic clouds, which affect modeled cloud phase, cloud lifetime and radiative properties. An ice nucleation parameterization and a vapor deposition scheme were developed that together provide a physically-consistent treatment of mixed-phase clouds in global climate models. These schemes have been implemented in the National Center for Atmospheric Research (NCAR) Community Atmospheric Model Version 3 (CAM3). This report documents the performance of these schemes against ARM Mixed-phase Arctic Cloud Experiment (M-PACE) observations using the CAM single column model version (SCAM). SCAM with our new schemes has a more realistic simulation of the cloud phase structure and the partitioning of condensed water into liquid droplets against observations during the M-PACE than the standard CAM simulations.

Liu, X; Ghan, SJ; Xie, S

2007-04-01T23:59:59.000Z

138

DOE/SC-ARM-10-021 STORMVEX: The Storm Peak Lab Cloud Property Validation Experiment  

NLE Websites -- All DOE Office Websites (Extended Search)

1 1 STORMVEX: The Storm Peak Lab Cloud Property Validation Experiment Science and Operations Plan J Mace Principal Investigator S Matrosov B Orr M Shupe R Coulter P Lawson A Sedlacek G Hallar L Avallone I McCubbin C Long R Marchand September 2010 DISCLAIMER This report was prepared as an account of work sponsored by the U.S. Government. Neither the United States nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service

139

Thin Liquid Water Clouds: Their Importance and Our Challenge  

Science Conference Proceedings (OSTI)

Many of the clouds important to the Earth's energy balance, from the Tropics to the Arctic, contain small amounts of liquid water. Longwave and shortwave radiative fluxes are very sensitive to small perturbations of the cloud liquid water path (...

D. D. Turner; A. M. Vogelmann; K. Johnson; M. Miller; R. T. Austin; J. C. Barnard; C. Flynn; C. Long; S. A. McFarlane; K. Cady-Pereira; S. A. Clough; J. C. Chiu; M. M. Khaiyer; J. Liljegren; B. Lin; P. Minnis; A. Marshak; S. Y. Matrosov; Q. Min; W. O'Hirok; Z. Wang; W. Wiscombe

2007-02-01T23:59:59.000Z

140

Arctic house  

E-Print Network (OSTI)

Currently available housing in the Arctic is limited to solutions that have been adapted from designs for less severe climates. This thesis has developed a new manner of residential construction designed specifically for ...

Turkel, Joel A. (Joel Abram), 1969-

1999-01-01T23:59:59.000Z

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


141

Multiparameter AVHRR-Derived Products for Arctic Climate Studies  

Science Conference Proceedings (OSTI)

Generation and sample applications of an integrated set of remotely sensed products for investigations of Arctic climate are described. Cloud fraction, ice surface temperature, surface albedo, downwelling radiative fluxes, ice motion vectors, and ...

Walter N. Meier; James A. Maslanik; Charles W. Fowler; Jeffrey R. Key

1997-01-01T23:59:59.000Z

142

Statistical Analysis of Forecasting Models across the North Slope of Alaska during the Mixed-Phase Arctic Clouds Experiment  

Science Conference Proceedings (OSTI)

The National Centers for Environmental Prediction’s (NCEP) Eta Model, the models of the European Centre for Medium-Range Weather Forecasts (ECMWF) and the National Aeronautics and Space Administration’s (NASA) Global Modeling and Assimilation ...

Victor T. Yannuzzi; Eugene E. Clothiaux; Jerry Y. Harrington; Johannes Verlinde

2009-12-01T23:59:59.000Z

143

Evaluation of a New Mixed-Phase Cloud Microphysics Parameterization with CAM3 Single-Column Model and M-PACE Observations  

SciTech Connect

Most global climate models generally prescribe the partitioning of condensed water into liquid droplets and ice crystals in mixed-phase clouds according to a temperature-dependent function, which affects modeled cloud phase, cloud lifetime and radiative properties. This study evaluates a new mixed-phase cloud microphysics parameterization (for ice nucleation and water vapor deposition) against the Atmospheric Radiation Measurement (ARM) Mixed-phase Arctic Cloud Experiment (M-PACE) observations using the NCAR Community Atmospheric Model Version 3 (CAM3) single column model (SCAM). It is shown that SCAM with the new scheme produces a more realistic simulation of the cloud phase structure and the partitioning of condensed waterinto liquid droplets against observations during the M-PACE than the standard CAM. Sensitivity test indicates that ice number concentration could play an important role in the simulated mixed-phase cloud microphysics, and thereby needs to be realistically represented in global climate models.

Liu, Xiaohong; Xie, Shaocheng; Ghan, Steven J.

2007-12-14T23:59:59.000Z

144

Improvements in Representations of Cloud Microphysics for BBHRP and Models using Data Collected during M-PACE and TWP-ICE  

SciTech Connect

In our research we proposed to use data collected during the 2004 Mixed-Phase Arctic Cloud Experiment (MPACE) and the 2006 Tropical Warm Pool International Cloud Experiment (TWP-ICE) to improve retrievals of ice and mixed-phase clouds, to improve our understanding of how cloud and radiative processes affect cloud life cycles, and to develop and test methods for using ARM data more effectively in model. In particular, we proposed to: 1) use MPACE in-situ data to determine how liquid water fraction and cloud ice and liquid effective radius (r{sub ei} and r{sub ew}) vary with temperature, normalized cloud altitude and other variables for Arctic mixed-phase clouds, and to use these data to evaluate the performance of model parameterization schemes and remote sensing retrieval algorithms; 2) calculate rei and size/shape distributions using TWP-ICE in-situ data, investigate their dependence on cirrus type (oceanic or continental anvils or cirrus not directly traced to convection), and develop and test representations for MICROBASE; 3) conduct fundamental research enhancing our understanding of cloud/radiative interactions, concentrating on effects of small crystals and particle shapes and sizes on radiation; and 4) improve representations of microphysical processes for models (fall-out, effective density, mean scattering properties, rei and rew) and provide them to ARM PIs. In the course of our research, we made substantial progress on all four goals.

Greg M. McFarquhar

2010-02-22T23:59:59.000Z

145

Temporal Interpolation Methods for the Clouds and the Earth’s Radiant Energy System (CERES) Experiment  

Science Conference Proceedings (OSTI)

The Clouds and the Earth’s Radiant Energy System (CERES) is a NASA multisatellite measurement program for monitoring the radiation environment of the earth–atmosphere system. The CERES instrument was flown on the Tropical Rainfall Measuring ...

D. F. Young; P. Minnis; D. R. Doelling; G. G. Gibson; T. Wong

1998-06-01T23:59:59.000Z

146

The Arctic Lower Troposphere Observed Structure (ALTOS) Campaign  

SciTech Connect

The ALTOS campaign focuses on operating a tethered observing system for routine in situ sampling of low-level (< 2 km) Arctic clouds. It has been a long-term hope to fly tethered systems at Barrow, Alaska, but it is clear that the Federal Aviation Administration (FAA) will not permit in-cloud tether systems at Barrow, even if unmanned aerial vehicle (UAV) operations are allowed in the future. We have provided the scientific rationale for long-term, routine in situ measurements of cloud and aerosol properties in the Arctic. The existing restricted air space at Oliktok offers an opportunity to do so.

Verlinde, J

2010-10-18T23:59:59.000Z

147

Frostbite Theater - Experiments You Can Try at Home! - How to Make a Cloud  

NLE Websites -- All DOE Office Websites (Extended Search)

Calculations and Results Calculations and Results Previous Video (Calculations and Results) Frostbite Theater Main Index Next Video (Squealing Dry Ice) Squealing Dry Ice How to Make a Cloud Chamber! A cloud chamber is a simple device that allows you to observe the decay of radioactive materials. Learn how to build your own! While it isn't difficult to build, it does require dry ice, isopropanol and a source of radiation, all of which are commercially available. [ Show Transcript ] Announcer: Frostbite Theater presents... Cold Cuts! No baloney! Joanna and Steve: Just science! Joanna: Hi! I'm Joanna! Steve: And I'm Steve! Joanna: Today, we're going to show you how to make a cloud chamber! Steve: Yay! Joanna: First, you're going to need a piece of black construction paper, a pair of scissors, some sticky-back felt, a Petri dish with a lid, some

148

A 70-Year History of Marine Stratocumulus Cloud Field Experiments off the Coast of California  

Science Conference Proceedings (OSTI)

On 10 September 1923, the first research aircraft flight to investigate marine stratocumulus clouds took place. As we approach the 70th anniversary of this historic flight, it is important to look back at what we have learned from the field ...

Kevin A. Kloesel

1992-10-01T23:59:59.000Z

149

Results of the South African Cloud-Seeding Experiments Using Hygroscopic Flares  

Science Conference Proceedings (OSTI)

A new method of seeding convective clouds for the purpose of augmenting rainfall is being developed in South Africa. Flares that produce small salt particles (0.5-?m mean diameter) are attached to the trailing edge of the wings of seeding ...

G. K. Mather; D. E. Terblanche; F. E. Steffens; L. Fletcher

1997-11-01T23:59:59.000Z

150

A Coordinated Effort to Improve Parameterization of High-Latitude Cloud and Radiation Processes  

SciTech Connect

The goal of this project is the development and evaluation of improved parameterization of arctic cloud and radiation processes and implementation of the parameterizations into a climate model. Our research focuses specifically on the following issues: (1) continued development and evaluation of cloud microphysical parameterizations, focusing on issues of particular relevance for mixed phase clouds; and (2) evaluation of the mesoscale simulation of arctic cloud system life cycles.

J. O. Pinto, A.H. Lynch

2005-12-14T23:59:59.000Z

151

Using Surface Remote Sensors to Derive Mixed-Phase Cloud Radiative Forcing:  

NLE Websites -- All DOE Office Websites (Extended Search)

Using Surface Remote Sensors to Derive Mixed-Phase Cloud Radiative Forcing: Using Surface Remote Sensors to Derive Mixed-Phase Cloud Radiative Forcing: An Example from M-PACE Title Using Surface Remote Sensors to Derive Mixed-Phase Cloud Radiative Forcing: An Example from M-PACE Publication Type Journal Article Year of Publication 2011 Authors de Boer, Gijs, William D. Collins, Surabi Menon, and Charles N. Long Journal Atmospheric Chemistry and Physics Volume 11 Start Page 11937 Pagination 11937-11949 Abstract Measurements from ground-based cloud radar, high spectral resolution lidar and microwave radiometer are used in conjunction with a column version of the Rapid Radiative Transfer Model (RRTMG) and radiosonde measurements to derive the surface radiative properties under mixed-phase cloud conditions. These clouds were observed during the United States Department of Energy (US DOE) Atmospheric Radiation Measurement (ARM) Mixed-Phase Arctic Clouds Experiment (M-PACE) between September and November of 2004. In total, sixteen half hour time periods are reviewed due to their coincidence with radiosonde launches. Cloud liquid (ice) water paths are found to range between 11.0-366.4 (0.5-114.1) gm-2, and cloud physical thicknesses fall between 286-2075 m. Combined with temperature and hydrometeor size estimates, this information is used to calculate surface radiative flux densities using RRTMG, which are demonstrated to generally agree with measured flux densities from surface-based radiometric instrumentation. Errors in longwave flux density estimates are found to be largest for thin clouds, while shortwave flux density errors are generally largest for thicker clouds. A sensitivity study is performed to understand the impact of retrieval assumptions and uncertainties on derived surface radiation estimates. Cloud radiative forcing is calculated for all profiles, illustrating longwave dominance during this time of year, with net cloud forcing generally between 50 and 90 Wm-2.

152

Storm Studies in the Arctic (STAR)  

Science Conference Proceedings (OSTI)

The Storm Studies in the Arctic (STAR) network (2007–2010) conducted a major meteorological field project from 10 October–30 November 2007 and in February 2008, focused on southern Baffin Island, Nunavut, Canada—a region that experiences intense ...

John Hanesiak; Ronald Stewart; David Barber; George Liu; Justin Gilligan; Danielle Desjardins; Robyn Dyck; Shannon Fargey; Klaus Hochheim; Rebekah Martin; Peter Taylor; Sumita Biswas; Mark Gordon; Marna Albarran Melzer; Kent Moore; Robert Field; Carling Hay; Shunli Zhang; Gordon McBean; Walter Strapp; David Hudak; John Scott; Mengistu Wolde; Ron Goodson; Edward Hudson; Gabrielle Gascon; Heather Greene; William Henson; Alex Laplante

2010-01-01T23:59:59.000Z

153

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

SciTech Connect

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

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

2007-09-30T23:59:59.000Z

154

Electron-Cloud Build-Up Simulations and Experiments at CERN  

E-Print Network (OSTI)

We benchmark the predictions of electron-cloud buildup simulations against measurements at the CERN SPS. Specifically we compare the electron flux at the wall, electron-energy spectra, heat loads and the spatial distribution of the electrons for two different bunch spacings, with variable magnetic fields, and for several chamber temperatures and associated surface conditions. The simulations employ a modified, improved version of the ECLOUD code. The main changes are briefly described. We finally present updated simulation results for the heat load in the cold LHC arcs.

Arduini, Gianluigi; Bohl, T; Jenninger, B; Jiménez, M; Laurent, Jean Michel; Schulte, Daniel; Ruggiero, F; Zimmermann, Frank

2004-01-01T23:59:59.000Z

155

Anvil characteristics as seen by C-POL during the Tropical Warm Pool International Cloud Experiment (TWP-ICE)  

E-Print Network (OSTI)

The Tropical Pacific Warm Pool International Cloud Experiment (TWP-ICE) took place in Darwin, Australia in early 2006. C-band radar data from this experiment were used to characterize tropical anvil areal coverage, height, and thickness during the month-long field campaign. The morphology, evolution, and longevity of the anvil were analyzed as well as the relationship of the anvil to the rest of the precipitating system. In addition, idealized in-cloud radiative heating profiles were created based on the anvil observations. The anvil was separated into mixed (i.e., echo base below 6 km) and ice only categories. The experiment areal average coverage for both types of anvil was between 4-5% of the radar grid. Ice anvil thickness averaged 2.8 km and mixed anvil thickness averaged 6.7 km. No consistent diurnal signal was seen in the anvil, implying that the life cycle of the parent convection was of first order importance in determining the anvil height, thickness, and area. Areal peaks show that mixed anvil typically formed out of the stratiform region. Peak production in ice anvil usually followed the mixed anvil peak by 1-3 hr. Anvil typically lasted 4-10 hr after the initial convective rain area peak. The TWP-ICE experienced three distinct regimes: the active monsoon, dry monsoon, and break periods. During the entire experiment (except the active monsoon period) there was a strong negative correlation between ice anvil thickness and ice anvil height, a strong positive correlation between ice anvil area and thickness, and a greater variance in ice anvil bottom than ice anvil top. Anvil produced during the active regime had the most dramatic in-cloud radiative response with a maximum cooling of 0.45�° K day-1 at 12 km, a maximum heating of 3�° K day-1 at 9 km, and a secondary maximum heating of 1.2�° K day-1 at 5 km.

Frederick, Kaycee Loretta

2006-12-01T23:59:59.000Z

156

Testing ice microphysics parameterizations in the NCAR Community Atmospheric Model Version 3 using Tropical Warm Pool–International Cloud Experiment data  

SciTech Connect

Cloud properties have been simulated with a new double-moment microphysics scheme under the framework of the single column version of NCAR CAM3. For comparisons, the same simulation was made with the standard single-moment microphysics scheme of CAM3. Results from both simulations were compared favorably with observations during the Tropical Warm Pool- International Cloud Experiment by US Department of Energy Atmospheric Radiation Program in terms of the temporal variation and vertical distribution of cloud fraction and cloud condensate. Major differences between the two simulations are in the magnitude and distribution of ice water content within the mixed-phase cloud during the monsoon period, though the total frozen water (snow plus ice) content is similar. The ice mass content in the mixed-phase cloud from the new scheme is larger than that from the standard scheme, and extends 2 km further downward, which are closer to observations. The dependence of the frozen water mass fraction in total condensate on temperature from the new scheme is also closer to available observations. Outgoing longwave radiation (OLR) at the top of the atmosphere (TOA) from the simulation with the new scheme is in general larger than that with the standard scheme, while the surface downward longwave radiation is similar. Sensitivity tests suggest that different treatments of the ice effective radius contribute significantly to the difference in the TOA OLR in addition to cloud water path. The deep convection process affects both TOA OLR and surface downward longwave radiation. The over-frequently-triggered deep convention process in the model is not the only mechanism for the excess middle and high level clouds. Further evaluation especially for ice cloud properties based on in-situ data is needed.

Wang, Weiguo; Liu, Xiaohong; Xie, Shaocheng; Boyle, James; McFarlane, Sally A.

2009-07-23T23:59:59.000Z

157

Toward an Explanation of the Annual Cycle of Cloudiness over the Arctic Ocean  

Science Conference Proceedings (OSTI)

The annual cycle of low cloud amount over the Arctic Ocean is examined using climatological data and a radiative-turbulent column model. Three hypotheses for the annual cycle are formulated, compared with climatological data for consistency, and ...

J. A. Beesley; R. E. Moritz

1999-02-01T23:59:59.000Z

158

A New Chicane Experiment In PEP-II to Test Mitigations of the Electron Cloud Effect for Linear Colliders  

Science Conference Proceedings (OSTI)

Beam instability caused by the electron cloud has been observed in positron and proton storage rings, and it is expected to be a limiting factor in the performance of future colliders [1-3]. The effect is expected to be particularly severe in magnetic field regions. To test possible mitigation methods in magnetic fields, we have installed a new 4-dipole chicane experiment in the PEP-II Low Energy Ring (LER) at SLAC with both bare and TiN-coated aluminum chambers. In particular, we have observed a large variation of the electron flux at the chamber wall as a function of the chicane dipole field. We infer this is a new high order resonance effect where the energy gained by the electrons in the positron beam depends on the phase of the electron cyclotron motion with respect to the bunch crossing, leading to a modulation of the secondary electron production. Presumably the cloud density is modulated as well and this resonance effect could be used to reduce its magnitude in future colliders. We present the experimental results obtained during January 2008 until the April final shut-down of the PEP-II machine.

Pivi, M.T.F.; Ng, J.S.T.; Arnett, D.; Cooper, F.; Kharakh, D.; King, F.K.; Kirby, R.E.; Kuekan, B.; Lipari, J.J.; Munro, M.; Olszewski, J.; Raubenheimer, T.O.; Seeman, J.; Smith, B.; Spencer, C.M.; Wang, L.; Wittmer, W.; Celata, C.M.; Furman, M.A.; /SLAC /LBL, Berkeley

2008-07-03T23:59:59.000Z

159

The Arctic Haze Phenomenon  

Science Conference Proceedings (OSTI)

The arctic atmosphere is the repository for surprisingly high concentrations of pollutants throughout the winter months. The polluted air mass in question includes virtually all the atmosphere above the Arctic Circle and also two great lobes that ...

Glenn E. Shaw

1995-12-01T23:59:59.000Z

160

Results of the Thailand Warm-Cloud Hygroscopic Particle Seeding Experiment  

Science Conference Proceedings (OSTI)

A randomized, warm-rain enhancement experiment was carried out during 1995–98 in the Bhumibol catchment area in northwestern Thailand. The experiment was conducted in accordance with a randomized, floating single–target design. The seeding ...

Bernard A. Silverman; Wathana Sukarnjanaset

2000-07-01T23:59:59.000Z

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


161

The Effects of Different Climate Input Datasets on Simulated Carbon Dynamics in the Western Arctic  

Science Conference Proceedings (OSTI)

As part of the Western Arctic Linkage Experiment (WALE), simulations of carbon dynamics in the western Arctic (WALE region) were conducted during two recent decades by driving the Terrestrial Ecosystem Model (TEM) with three alternative climate ...

Joy Clein; A. David McGuire; Eugenie S. Euskirchen; Monika Calef

2007-08-01T23:59:59.000Z

162

ARM - Field Campaign - Boundary Layer Cloud IOP  

NLE Websites -- All DOE Office Websites (Extended Search)

govCampaignsBoundary Layer Cloud IOP govCampaignsBoundary Layer Cloud IOP Campaign Links Campaign Images Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Boundary Layer Cloud IOP 2005.07.11 - 2005.08.07 Lead Scientist : William Shaw For data sets, see below. Description Investigators from Pacific Northwest National Laboratory, in collaboration with scientists from a number of other institutions, carried out a month of intensive measurements at the ARM Climate Research Facility on the North Slope of Alaska in the summer of 2005. The purpose of these measurements was to determine how much the arctic land surface modifies the way low clouds reflect, absorb, and transmit solar and infrared radiation. This is an important problem because arctic clouds play a prominent role in

163

A Potential Role for Immersion Freezing in Arctic Mixed-Phase Stratus  

NLE Websites -- All DOE Office Websites (Extended Search)

Potential Role for Immersion Freezing in Arctic Mixed-Phase Stratus Potential Role for Immersion Freezing in Arctic Mixed-Phase Stratus Gijs de Boer, Edwin W. Eloranta, Tempei Hashino, and Gregory J. Tripoli The University of Wisconsin - Madison (1) Introduction Ice formation appears to a dominant factor controlling the lifecycle of Arctic mixed-phase clouds. To date, our understanding of ice formation in these long-lasting cloud structures does not explain the formation of observed ice amounts. Particularly puzzling are observa-

164

Further Exploratory Analysis of the Bridger Range Winter Cloud Seeding Experiment  

Science Conference Proceedings (OSTI)

Further exploratory analysis of the Bridger Range Experiment was carried out with 6 h data blocks partitioned from the original 24 h experimental units. The analysis was limited to 6 h periods having a rawinsonde observation, Main Ridge ...

Arlin D. Super

1986-12-01T23:59:59.000Z

165

ARM - Publications: Science Team Meeting Documents: Clouds and radiation in  

NLE Websites -- All DOE Office Websites (Extended Search)

Clouds and radiation in the Arctic coastal system - effects of local Clouds and radiation in the Arctic coastal system - effects of local heterogeneity Key, Erica University of Miami, RSMAS Minnett, Peter University of Miami Improving our comprehension of the influence of clouds in the polar regions is important as a prerequisite to refining our understanding of the earth's climate system. Polar clouds modulate the radiative heat loss to space in the regions that serve as the heat sink of the climate system. The local feedbacks between cloud formation and changing surface albedo that result from the ice melting and refreezing cycle, and the small space scales over which significant gradients occur, render this a very complex system to study. Difficulties in making appropriate measurements in the harsh Arctic environment lead to sparse, if not absent information on the

166

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

SciTech Connect

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

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

2011-01-21T23:59:59.000Z

167

ARM tropical pacific experiment (ATPEX): Role of cloud, water vapor and convection feedbacks in the coupled ocean/atmosphere system  

SciTech Connect

We have initiated studies that include radiation model validation, improved treatment of the three-dimensional structure of cloud-radiation interactions, and sensitivity runs that will unravel the role of cloud-convection-radiation interactions in the Pacific Sear Surface Temperatures and the overlying Walker and Hadley circulation. The research program is divided into three phases: (1) radiation, (2) cloud parameterization issues; (3) feedback and ocean-atmosphere interactions.

Ramanathan, V.; Barnett, T.P.

1992-03-05T23:59:59.000Z

168

Monitoring of Precipitable Water Vapor and Cloud Liquid Path from Scanning Microwave Radiometers During the 2003 Cloudiness Inter-Comparison Experiment  

NLE Websites -- All DOE Office Websites (Extended Search)

Monitoring of Precipitable Water Vapor and Cloud Liquid Monitoring of Precipitable Water Vapor and Cloud Liquid Path from Scanning Microwave Radiometers During the 2003 Cloudiness Inter-Comparison Experiment V. Mattioli Department of Electronic and Information Engineering University of Perugia Perugia, Italy E. R. Westwater Cooperative Institute for Research in Environmental Sciences University of Colorado National Oceanic and Atmospheric Administration Environmental Technology Laboratory Boulder, Colorado V. Morris Pacific Northwest National Laboratory Richland, Washington Introduction Ground-based microwave radiometers (MWR) are widely used to measure atmospheric precipitable water vapor (PWV) and cloud liquid path (CLP). Comparisons of PWV derived from MWRs with water vapor retrievals from instruments like radiosondes, Global Positioning System (GPS) and Raman

169

Warming Trends in the Arctic from Clear Sky Satellite Observations  

Science Conference Proceedings (OSTI)

Satellite thermal infrared data on surface temperatures provide pan-Arctic coverage from 1981 to 2001 during cloud-free conditions and reveal large warming anomalies in the 1990s compared to the 1980s and regional variability in the trend. The ...

Josefino C. Comiso

2003-11-01T23:59:59.000Z

170

IC cloud: Enabling compositional cloud  

Science Conference Proceedings (OSTI)

Cloud computing has attracted great interest from both academic and industrial communities. Different paradigms, architectures and applications based on the concept of cloud have emerged. Although many of them have been quite successful, efforts are ... Keywords: Cloud computing, cloud elasticity, cloud service, compositional cloud, infrastructure as a service (IaaS)

Yi-Ke Guo; Li Guo

2011-08-01T23:59:59.000Z

171

Comparison of Airborne In Situ, Airborne Radar–Lidar, and Spaceborne Radar–Lidar Retrievals of Polar Ice Cloud Properties Sampled during the POLARCAT Campaign  

Science Conference Proceedings (OSTI)

This study illustrates the high potential of RALI, the French airborne radar–lidar instrument, for studying cloud processes and evaluating satellite products when satellite overpasses are available. For an Arctic nimbostratus ice cloud collected ...

Julien Delanoë; Alain Protat; Olivier Jourdan; Jacques Pelon; Mathieu Papazzoni; Régis Dupuy; Jean-Francois Gayet; Caroline Jouan

2013-01-01T23:59:59.000Z

172

NETL: Arctic Energy Office  

NLE Websites -- All DOE Office Websites (Extended Search)

The Arctic Energy Office image showing Alaska landscape Alaska North Slope Resources Alaska Unconventional Resources ChallengesShortages AEO Program Fact Sheet Alaskas fossil...

173

ARM - Midlatitude Continental Convective Clouds Experiment (MC3E): Multi-Frequency Profilers, Surface Meteorology (williams-surfmet)  

DOE Data Explorer (OSTI)

This data was collected by the NOAA 449-MHz and 2.8-GHz profilers in support of the Department of Energy (DOE) and NASA sponsored Mid-latitude Continental Convective Cloud Experiment (MC3E). The profiling radars were deployed in Northern Oklahoma at the DOE Atmospheric Radiation Mission (ARM) Southern Great Plans (SGP) Central Facility from 22 April through 6 June 2011. NOAA deployed three instruments: a Parsivel disdrometer, a 2.8-GHz profiler, and a 449-MHz profiler. The parasivel provided surface estimates of the raindrop size distribution and is the reference used to absolutely calibrate the 2.8 GHz profiler. The 2.8-GHz profiler provided unattenuated reflectivity profiles of the precipitation. The 449-MHz profiler provided estimates of the vertical air motion during precipitation from near the surface to just below the freezing level. By using the combination of 2.8-GHz and 449-MHz profiler observations, vertical profiles of raindrop size distributions can be retrieved. The profilers are often reference by their frequency band: the 2.8-GHz profiler operates in the S-band and the 449-MHz profiler operates in the UHF band. The raw observations are available as well as calibrated spectra and moments. This document describes how the instruments were deployed, how the data was collected, and the format of the archived data.

Christopher Williams; Mike Jensen

174

ARM - Midlatitude Continental Convective Clouds Experiment (MC3E): Multi-Frequency Profilers, Vertical Air Motion (williams-vertair)  

DOE Data Explorer (OSTI)

This data was collected by the NOAA 449-MHz and 2.8-GHz profilers in support of the Department of Energy (DOE) and NASA sponsored Mid-latitude Continental Convective Cloud Experiment (MC3E). The profiling radars were deployed in Northern Oklahoma at the DOE Atmospheric Radiation Mission (ARM) Southern Great Plans (SGP) Central Facility from 22 April through 6 June 2011. NOAA deployed three instruments: a Parsivel disdrometer, a 2.8-GHz profiler, and a 449-MHz profiler. The parasivel provided surface estimates of the raindrop size distribution and is the reference used to absolutely calibrate the 2.8 GHz profiler. The 2.8-GHz profiler provided unattenuated reflectivity profiles of the precipitation. The 449-MHz profiler provided estimates of the vertical air motion during precipitation from near the surface to just below the freezing level. By using the combination of 2.8-GHz and 449-MHz profiler observations, vertical profiles of raindrop size distributions can be retrieved. The profilers are often reference by their frequency band: the 2.8-GHz profiler operates in the S-band and the 449-MHz profiler operates in the UHF band. The raw observations are available as well as calibrated spectra and moments. This document describes how the instruments were deployed, how the data was collected, and the format of the archived data.

Christopher Williams; Mike Jensen

175

ARM - Midlatitude Continental Convective Clouds Experiment (MC3E): Multi-Frequency Profilers, Parcivel Disdrometer (williams-disdro)  

DOE Data Explorer (OSTI)

This data was collected by the NOAA 449-MHz and 2.8-GHz profilers in support of the Department of Energy (DOE) and NASA sponsored Mid-latitude Continental Convective Cloud Experiment (MC3E). The profiling radars were deployed in Northern Oklahoma at the DOE Atmospheric Radiation Mission (ARM) Southern Great Plans (SGP) Central Facility from 22 April through 6 June 2011. NOAA deployed three instruments: a Parsivel disdrometer, a 2.8-GHz profiler, and a 449-MHz profiler. The parasivel provided surface estimates of the raindrop size distribution and is the reference used to absolutely calibrate the 2.8 GHz profiler. The 2.8-GHz profiler provided unattenuated reflectivity profiles of the precipitation. The 449-MHz profiler provided estimates of the vertical air motion during precipitation from near the surface to just below the freezing level. By using the combination of 2.8-GHz and 449-MHz profiler observations, vertical profiles of raindrop size distributions can be retrieved. The profilers are often reference by their frequency band: the 2.8-GHz profiler operates in the S-band and the 449-MHz profiler operates in the UHF band. The raw observations are available as well as calibrated spectra and moments. This document describes how the instruments were deployed, how the data was collected, and the format of the archived data.

Christopher Williams; Mike Jensen

176

ARM - Midlatitude Continental Convective Clouds Experiment (MC3E): Multi-Frequency Profilers, 449 MHz Profiler(williams-449_prof)  

DOE Data Explorer (OSTI)

This data was collected by the NOAA 449-MHz and 2.8-GHz profilers in support of the Department of Energy (DOE) and NASA sponsored Mid-latitude Continental Convective Cloud Experiment (MC3E). The profiling radars were deployed in Northern Oklahoma at the DOE Atmospheric Radiation Mission (ARM) Southern Great Plans (SGP) Central Facility from 22 April through 6 June 2011. NOAA deployed three instruments: a Parsivel disdrometer, a 2.8-GHz profiler, and a 449-MHz profiler. The parasivel provided surface estimates of the raindrop size distribution and is the reference used to absolutely calibrate the 2.8 GHz profiler. The 2.8-GHz profiler provided unattenuated reflectivity profiles of the precipitation. The 449-MHz profiler provided estimates of the vertical air motion during precipitation from near the surface to just below the freezing level. By using the combination of 2.8-GHz and 449-MHz profiler observations, vertical profiles of raindrop size distributions can be retrieved. The profilers are often reference by their frequency band: the 2.8-GHz profiler operates in the S-band and the 449-MHz profiler operates in the UHF band. The raw observations are available as well as calibrated spectra and moments. This document describes how the instruments were deployed, how the data was collected, and the format of the archived data.

Christopher Williams; Mike Jensen

177

Thermodynamic phase profiles of optically thin midlatitude clouds and their relation to temperature  

E-Print Network (OSTI)

parameterizations of cloud phase in general circulation models. However, other aircraft campaigns and different in the Arctic. The relationship between ice phase occurrence and temperature only slightly changes between cloud interest, as they occur in a temperature range where cloud phase can either be liquid, ice, or mixed

178

Regional Model Simulations of Marine Boundary Layer Clouds over the Southeast Pacific off South America. Part I: Control Experiment  

Science Conference Proceedings (OSTI)

A regional climate model is used to simulate boundary layer stratocumulus (Sc) clouds over the southeast Pacific off South America during August–October 1999 and to study their dynamical, radiative, and microphysical properties and their ...

Yuqing Wang; Shang-Ping Xie; Haiming Xu; Bin Wang

2004-01-01T23:59:59.000Z

179

Arctic Lower Troposphere Observed Structure (ALTOS)  

NLE Websites -- All DOE Office Websites (Extended Search)

Lower Troposphere Observed Structure (ALTOS) Lower Troposphere Observed Structure (ALTOS) will raise and lower a heavily instrumented tethered balloon system at regular intervals in the lower 2 kilometers of the atmosphere at Oliktok Point. Data obtained during the ALTOS campaign will provide a statistically significant set of observed in situ cloud properties for validating retrieval algorithms and help scientists reduce the uncertainty in the radiative forcing and heating rates on hourly time scales. The data will also help researchers gain a better understanding of the driving processes that control climate changes and determine the state of the Arctic climate system. Collaborators Science Team: The Pennsylvania State University, Stratton

180

The Impact of Polar Stratospheric Clouds on the Heating Rates of the Winter Polar Stratosphere  

Science Conference Proceedings (OSTI)

We have computed the perturbation to the infrared radiative heating rates of the lower stratosphere due to the occurrence of polar stratospheric clouds (PSCs) during the winter season in the Antarctic and Arctic regions. The calculations were ...

James B. Pollack; Christopher P. McKay

1985-02-01T23:59:59.000Z

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


181

Surface Heat Budget of the Arctic Ocean  

Science Conference Proceedings (OSTI)

A summary is presented of the Surface Heat Budget of the Arctic Ocean (SHEBA) project, with a focus on the field experiment that was conducted from October 1997 to October 1998. The primary objective of the field work was to collectocean, ice, ...

Taneil Uttal; Judith A. Curry; Miles G. Mcphee; Donald K. Perovich; Richard E. Moritz; James A. Maslanik; Peter S. Guest; Harry L. Stern; James A. Moore; Rene Turenne; Andreas Heiberg; Mark C. Serreze; Donald P. Wylie; Ola G. Persson; Clayton A. Paulson; Christopher Halle; James H. Morison; Patricia A. Wheeler; Alexander Makshtas; Harold Welch; Matthew D. Shupe; Janet M. Intrieri; Knut Stamnes; Ronald W. Lindsey; Robert Pinkel; W. Scott Pegau; Timothy P. Stanton; Thomas C. Grenfeld

2002-02-01T23:59:59.000Z

182

Arctic Solar | Open Energy Information  

Open Energy Info (EERE)

search Name Arctic Solar Place G"LLIVARE, Sweden Zip SE- 98228 Product manufacturers of PV modules References Arctic Solar1 LinkedIn Connections CrunchBase Profile No...

183

Final Technical Report for "Ice nuclei relation to aerosol properties: Data analysis and model parameterization for IN in mixed-phase clouds"Ă?Âť (DOE/SC00002354)  

Science Conference Proceedings (OSTI)

Clouds play an important role in weather and climate. In addition to their key role in the hydrologic cycle, clouds scatter incoming solar radiation and trap infrared radiation from the surface and lower atmosphere. Despite their importance, feedbacks involving clouds remain as one of the largest sources of uncertainty in climate models. To better simulate cloud processes requires better characterization of cloud microphysical processes, which can affect the spatial extent, optical depth and lifetime of clouds. To this end, we developed a new parameterization to be used in numerical models that describes the variation of ice nuclei (IN) number concentrations active to form ice crystals in mixed-phase (water droplets and ice crystals co-existing) cloud conditions as these depend on existing aerosol properties and temperature. The parameterization is based on data collected using the Colorado State University continuous flow diffusion chamber in aircraft and ground-based campaigns over a 14-year period, including data from the DOE-supported Mixed-Phase Arctic Cloud Experiment. The resulting relationship is shown to more accurately represent the variability of ice nuclei distributions in the atmosphere compared to currently used parameterizations based on temperature alone. When implemented in one global climate model, the new parameterization predicted more realistic annually averaged cloud water and ice distributions, and cloud radiative properties, especially for sensitive higher latitude mixed-phase cloud regions. As a test of the new global IN scheme, it was compared to independent data collected during the 2008 DOE-sponsored Indirect and Semi-Direct Aerosol Campaign (ISDAC). Good agreement with this new data set suggests the broad applicability of the new scheme for describing general (non-chemically specific) aerosol influences on IN number concentrations feeding mixed-phase Arctic stratus clouds. Finally, the parameterization was implemented into a regional cloud-resolving model to compare predictions of ice crystal concentrations and other cloud properties to those observed in two intensive case studies of Arctic stratus during ISDAC. Our implementation included development of a prognostic scheme of ice activation using the IN parameterization so that the most realistic treatment of ice nuclei, including their budget (gains and losses), was achieved. Many cloud microphysical properties and cloud persistence were faithfully reproduced, despite a tendency to under-predict (by a few to several times) ice crystal number concentrations and cloud ice mass, in agreement with some other studies. This work serves generally as the basis for improving predictive schemes for cloud ice crystal activation in cloud and climate models, and more specifically as the basis for such a scheme to be used in a Multi-scale Modeling Format (MMF) that utilizes a connected system of cloud-resolving models on a global grid in an effort to better resolve cloud processes and their influence on climate.

Paul J. DeMott, Anthony J. Prenni; Sonia M. Kreidenweis

2012-09-28T23:59:59.000Z

184

Stratocumulus Clouds  

Science Conference Proceedings (OSTI)

This paper reviews the current knowledge of the climatological, structural, and organizational aspects of stratocumulus clouds and the physical processes controlling them. More of Earth’s surface is covered by stratocumulus clouds than by any ...

Robert Wood

2012-08-01T23:59:59.000Z

185

On the Global Variation of Precipitating Layer Clouds  

Science Conference Proceedings (OSTI)

The aim of the Global Energy and Water Cycle Experiment Cloud System Study (GCSS) is to promote the description and understanding of key cloud system processes, with the aim of developing and improving the representation of cloud processes in ...

B. F. Ryan

1996-01-01T23:59:59.000Z

186

An Analytic Longwave Radiation Formula for Liquid Layer Clouds  

Science Conference Proceedings (OSTI)

Many Global Energy and Water Cycle Experiment (GEWEX) Cloud System Study (GCSS) intercomparisons of boundary layer clouds have used a convenient but idealized longwave radiation formula for clouds in their large-eddy simulations (LESs). Under ...

Vincent E. Larson; Kurt E. Kotenberg; Norman B. Wood

2007-02-01T23:59:59.000Z

187

Posters A One-Dimensional Radiative Convective Model with Detailed Cloud Microphysics  

NLE Websites -- All DOE Office Websites (Extended Search)

5 5 Posters A One-Dimensional Radiative Convective Model with Detailed Cloud Microphysics J. Simmons, O. Lie-Svendsen, and K. Stamnes Geophysical Institute University of Alaska Fairbanks, Alaska The Arctic is a key element in determining the radiation budget of the earth. Within the polar regions, the net radiation (incoming solar radiation minus outgoing infrared radiation) is negative. To understand the role this energy deficit plays in the overall radiation budget, one must examine the prevalent atmospheric features of the Arctic. One such feature is a persistent layer of low-altitude, stratiform clouds found over the central Arctic predominantly from April to September (Tsay et al. 1984). These Arctic stratus clouds (ASC) modulate the earth's radiation budget

188

Collaborative Research: Towards Advanced Understanding and Predictive Capability of Climate Change in the Arctic using a High-Resolution Regional Arctic Climate System Model  

Science Conference Proceedings (OSTI)

Primary activities are reported in these areas: climate system component studies via one-way coupling experiments; development of the Regional Arctic Climate System Model (RACM); and physical feedback studies focusing on changes in Arctic sea ice using the fully coupled model.

Lettenmaier, Dennis P

2013-04-08T23:59:59.000Z

189

Does Mixing Promote Cloud Droplet Growth?  

Science Conference Proceedings (OSTI)

A systematic examination of cloud droplet size spectra from the Cooperative Convective Precipitation Experiment (CCOPE) reveals no tendency for an increase in the maximum droplet size with increasing dilution or cloud age.

Ilga R. Paluch; Charles A. Knight

1986-09-01T23:59:59.000Z

190

CONTENTS Developing Alaskan Arctic  

NLE Websites -- All DOE Office Websites (Extended Search)

Developing Alaskan Arctic Developing Alaskan Arctic Potential ...........................................1 Commentary ...................................2 NETL Develops Strategic Partnership with the Alaska Center for Energy and Power ...8 Deepwater and Ultra-Deepwater Produced Water Discharge ....10 Intelligent Production System for Ultra Deepwater with Short Hop Wireless Power and Wireless Data Transfer .........................................16 Snapshots ......................................19 CONTACTS Roy Long Technology Manager Ultra-Deepwater/Offshore 304-285-4479 roy.long@netl.doe.gov Ray Boswell Technology Manager Natural Gas Technology R&D 412-386-7614 ray.boswell@netl.doe.gov Eric Smistad Technology Manager Oil Technology R&D 281-494-2619 eric.smistad@netl.doe.gov

191

Heat, Moisture, and Momentum Budgets of Isolated Deep Midlatitude and Tropical Convective Clouds as Diagnosed from Three-Dimensional Model Output. Part I: Control Experiments  

Science Conference Proceedings (OSTI)

This project uses a three-dimensional anelastic cloud model with a simple ice phase parameterization to evaluate the feedback between isolated deep convective clouds and their near surroundings. The horizontal Reynolds averaging approach of ...

Robert E. Schlesinger

1994-12-01T23:59:59.000Z

192

The Simulation of a Convective Cloud in a 3-D Model With Explicit Microphysics. Part I: Model Description and Sensitivity Experiments  

Science Conference Proceedings (OSTI)

A three-dimensional nonhydrostatic anelastic numerical model of a convective cloud with an explicit description of microphysical processes has been developed. Two distribution functions are considered in the model—one for cloud condensation ...

Yefim L. Kogan

1991-05-01T23:59:59.000Z

193

Arctic ice islands  

SciTech Connect

The development of offshore oil and gas resources in the Arctic waters of Alaska requires offshore structures which successfully resist the lateral forces due to moving, drifting ice. Ice islands are floating, a tabular icebergs, up to 60 meters thick, of solid ice throughout their thickness. The ice islands are thus regarded as the strongest ice features in the Arctic; fixed offshore structures which can directly withstand the impact of ice islands are possible but in some locations may be so expensive as to make oilfield development uneconomic. The resolution of the ice island problem requires two research steps: (1) calculation of the probability of interaction between an ice island and an offshore structure in a given region; and (2) if the probability if sufficiently large, then the study of possible interactions between ice island and structure, to discover mitigative measures to deal with the moving ice island. The ice island research conducted during the 1983-1988 interval, which is summarized in this report, was concerned with the first step. Monte Carlo simulations of ice island generation and movement suggest that ice island lifetimes range from 0 to 70 years, and that 85% of the lifetimes are less then 35 years. The simulation shows a mean value of 18 ice islands present at any time in the Arctic Ocean, with a 90% probability of less than 30 ice islands. At this time, approximately 34 ice islands are known, from observations, to exist in the Arctic Ocean, not including the 10-meter thick class of ice islands. Return interval plots from the simulation show that coastal zones of the Beaufort and Chukchi Seas, already leased for oil development, have ice island recurrences of 10 to 100 years. This implies that the ice island hazard must be considered thoroughly, and appropriate safety measures adopted, when offshore oil production plans are formulated for the Alaskan Arctic offshore. 132 refs., 161 figs., 17 tabs.

Sackinger, W.M.; Jeffries, M.O.; Lu, M.C.; Li, F.C.

1988-01-01T23:59:59.000Z

194

Radiative Impacts on the Growth of a Population of Drops within Simulated Summertime Arctic Stratus  

Science Conference Proceedings (OSTI)

The impact of solar heating and infrared cooling on the growth of a population of drops is studied with two numerical modeling frameworks. An eddy-resolving model (ERM) simulation of Arctic stratus clouds is used to generate a dataset of 500 ...

Jerry Y. Harrington; Graham Feingold; William R. Cotton

2000-03-01T23:59:59.000Z

195

Cloud Chmabers  

NLE Websites -- All DOE Office Websites (Extended Search)

Video - (Requires Windows Media Player) Build your own cloud chamber - Instructions Project Contact: Tom Jordan Web Maintainer: qnet-webmaster@fnal.gov Last Update: May 31, 2011...

196

Why sequence arctic algae for alternative energy?  

NLE Websites -- All DOE Office Websites (Extended Search)

arctic algae for alternative energy? Five different protists representing different algal classes isolated from the Arctic Ocean are being investigated for adaptation to perennial...

197

Plant roots in arctic tundra  

DOE Data Explorer (OSTI)

A synthesis of the available literature on tundra root distribution and dynamics, and their role in key ecosystem processes in the Arctic.

Colleen Iversen, Victoria Sloan, Paddy Sullivan, Eugenie Euskirchen, Dave McGuire, Richard Norby, Anthony Walker, Jeff Warren, Stan Wullschleger,

198

Properties of Tropical Cloud Ensembles Estimated Using a Cloud Model and an Observed Updraft Population  

Science Conference Proceedings (OSTI)

A simple cloud model is developed which is designed for both diagnostic studies and mesoscale cumulus parameterization experiments. The cloud model is combined with an observed population of tropical convective updrafts and used to examine the ...

William M. Frank; Charles Cohen

1985-09-01T23:59:59.000Z

199

Cellular clouds  

Science Conference Proceedings (OSTI)

This paper progresses an analysis of what it means to be a cellular network operator and what form the ownership and control of future cellular networks may take. Alternative modes of ownership may allow for the creation of more flexible cellular networking ... Keywords: Cellular Cloud, Cellular network, Cloud Computing, Cognitive radio, DSA, LTE, MVNO, Services, Utility Cellular Network

Tim Forde; Linda Doyle

2013-03-01T23:59:59.000Z

200

Marine Cloud Brightening  

Science Conference Proceedings (OSTI)

The idea behind the marine cloud-brightening (MCB) geoengineering technique is that seeding marine stratocumulus clouds with copious quantities of roughly monodisperse sub-micrometre sea water particles might significantly enhance the cloud droplet number concentration, and thereby the cloud albedo and possibly longevity. This would produce a cooling, which general circulation model (GCM) computations suggest could - subject to satisfactory resolution of technical and scientific problems identified herein - have the capacity to balance global warming up to the carbon dioxide-doubling point. We describe herein an account of our recent research on a number of critical issues associated with MCB. This involves (i) GCM studies, which are our primary tools for evaluating globally the effectiveness of MCB, and assessing its climate impacts on rainfall amounts and distribution, and also polar sea-ice cover and thickness; (ii) high-resolution modelling of the effects of seeding on marine stratocumulus, which are required to understand the complex array of interacting processes involved in cloud brightening; (iii) microphysical modelling sensitivity studies, examining the influence of seeding amount, seedparticle salt-mass, air-mass characteristics, updraught speed and other parameters on cloud-albedo change; (iv) sea water spray-production techniques; (v) computational fluid dynamics studies of possible large-scale periodicities in Flettner rotors; and (vi) the planning of a three-stage limited-area field research experiment, with the primary objectives of technology testing and determining to what extent, if any, cloud albedo might be enhanced by seeding marine stratocumulus clouds on a spatial scale of around 100 km. We stress that there would be no justification for deployment of MCB unless it was clearly established that no significant adverse consequences would result. There would also need to be an international agreement firmly in favour of such action.

Latham, John; Bower, Keith; Choularton, Tom; Coe, H.; Connolly, P.; Cooper, Gary; Craft, Tim; Foster, Jack; Gadian, Alan; Galbraith, Lee; Iacovides, Hector; Johnston, David; Launder, Brian; Leslie, Brian; Meyer, John; Neukermans, Armand; Ormond, Bob; Parkes, Ben; Rasch, Philip J.; Rush, John; Salter, Stephen; Stevenson, Tom; Wang, Hailong; Wang, Qin; Wood, Robert

2012-09-07T23:59:59.000Z

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


201

NETL: Arctic Energy Office  

NLE Websites -- All DOE Office Websites (Extended Search)

Facts/Issues Facts/Issues Average South-Central natural gas consumption in 2005 was: 13.9% gas utility 20.0% power generation 54.3% industrial-LNG sales, oil refining, and fertilizer manufacturing 7.2% field operations 4.6% other Due to a lack of natural gas deliverability, the Cook Inlet fertilizer plant terminated operations in May 2008. LNG sales are increasingly curtailed during cold weather due to peak demand shortages. The LNG export license is up for renewal in 2011. Exploration must find new reserves on the order of 500 Bcf, and that will only solve the natural gas shortage until approximately 2019. Challenges Natural gas in the Arctic, until recently, has been largely overlooked. Little is known about the possible breadth of the Arctic storehouse of natural gas apart from the resource associated with the currently producing

202

Arctic Energy Office  

NLE Websites -- All DOE Office Websites (Extended Search)

O O G R A M FAC T S Strategic Center for Natural Gas & Oil CONTACTS Joel Lindstrom Arctic Energy Office National Energy Technology Laboratory 420 L Street, Suite 305 Anchorage, Alaska 99501 907-271-3618 joel.lindstrom@contr.netl.doe.gov Albert B. Yost II Sr. Management Technical Advisor Strategic Center for Natural Gas & Oil National Energy Technology Laboratory 3610 Collins Ferry Road Morgantown, WV 26507-0880 304-285-4479 albert.yost@netl.doe.gov

203

The Transpose-AMIP II Experiment and Its Application to the Understanding of Southern Ocean Cloud Biases in Climate Models  

Science Conference Proceedings (OSTI)

The Transpose-Atmospheric Model Intercomparison Project (AMIP) is an international model intercomparison project in which climate models are run in “weather forecast mode.” The Transpose-AMIP II experiment is run alongside phase 5 of the Coupled ...

K. D. Williams; A. Bodas-Salcedo; M. Déqué; S. Fermepin; B. Medeiros; M. Watanabe; C. Jakob; S. A. Klein; C. A. Senior; D. L. Williamson

2013-05-01T23:59:59.000Z

204

ARM tropical pacific experiment (ATPEX): Role of cloud, water vapor and convection feedbacks in the coupled ocean/atmosphere system. Progress report, September 1, 1991--August 31, 1992  

SciTech Connect

We have initiated studies that include radiation model validation, improved treatment of the three-dimensional structure of cloud-radiation interactions, and sensitivity runs that will unravel the role of cloud-convection-radiation interactions in the Pacific Sear Surface Temperatures and the overlying Walker and Hadley circulation. The research program is divided into three phases: (1) radiation, (2) cloud parameterization issues; (3) feedback and ocean-atmosphere interactions.

Ramanathan, V.; Barnett, T.P.

1992-03-05T23:59:59.000Z

205

Cloud Cover and Climate Sensitivity  

Science Conference Proceedings (OSTI)

This study discusses how the sensitivity of climate may be affected by the variation of cloud cover based on the results from numerical experiments with a highly simplified, three-dimensional model of the atmospheric general circulation. The ...

Richard T. Wetherald; Syukuro Manabe

1980-07-01T23:59:59.000Z

206

Radiative Influences on Glaciation Time-Scales of Mixed-Phase Clouds  

NLE Websites -- All DOE Office Websites (Extended Search)

Radiative Influences on Glaciation Time-Scales of Mixed-Phase Clouds Radiative Influences on Glaciation Time-Scales of Mixed-Phase Clouds Harrington, Jerry The Pennsylvania State University Category: Modeling Mixed-phase stratus clouds are dominant in the Arctic during much of the year. These clouds typically have liquid tops that precipitate ice. Time scales for the complete glaciation of such clouds (the Bergeron process) are typically computed using the classical mass growth equations for crystals and liquid drops. However, mixed phase arctic stratus have significant infrared cooling and solar heating (during the warm season) rates that can affect the growth of water drops and ice crystals, and therefore the strength of the Bergeron process. To examine the influence of radiative heating and cooling on the Bergeron process, we incorporate a

207

Analysis of In situ Observations of Cloud Microphysics from M-PACE Final Report, DOE Grant Agreement No. DE-FG02-06ER64168  

SciTech Connect

This report summarizes the findings and accomplishments of work performed under DOE Grant Agreement No. DE-FG02-06ER64168. The focus of the work was the analysis of in situ observations collected by the University of North Dakota Citation research aircraft during the Mixed-Phase Arctic Cloud Experiment (M-PACE). This project was conducted in 2004 along the North Slope of Alaska. The objectives of the research were: to characterize certain microphysical properties of clouds sampled during M-PACE, including spatial variability, precipitation formation, ice multiplication; to examine instrument performance and certain data processing algorithms; and to collaborate with other M-PACE investigators on case study analyses. A summary of the findings of the first two objectives is given here in parts 1 and 2; full results are contained in reports listed in part 3 of this report. The collaborative efforts are described in the publications listed in part 3.

Michael R. Poellot

2009-01-09T23:59:59.000Z

208

Ground-based Microwave Cloud Tomography  

NLE Websites -- All DOE Office Websites (Extended Search)

Microwave Cloud Tomography Microwave Cloud Tomography Experiment, SGP, May 15-June 15, 2009 Lead Scientist Dong Huang, BNL Co-Investigators Al Gasiewski, UC Boulder Maria Cadeddu, ANL Warren Wiscombe, BNL Radiation Processes Working Group March 30, 2009 multiple radiometers All good cloud radiation modelers should close their airplane window shades so as not to be corrupted by the spectacle of real 3D clouds. - Roger Davies In case you forget to do this, you see 3/30/2009 ARM RPWG 2 Effects of cloud structure on radiation 3/30/2009 ARM RPWG 3 Typical climate model - Cloud fraction & mean water content - Horizontally uniform clouds, no side radiation - Assumption on overlap Courtesy of Bernhard Mayer Cloud structure important to radiation - Cumulus (Benner & Evans 2001, Pincus et al. 2005), deep convection (DiGiuseppe &

209

ARM - Midlatitude Continental Convective Clouds Experiment (MC3E): Multi-Frequency Profilers, S-band Radar (williams-s_band)  

DOE Data Explorer (OSTI)

This data was collected by the NOAA 449-MHz and 2.8-GHz profilers in support of the Department of Energy (DOE) and NASA sponsored Mid-latitude Continental Convective Cloud Experiment (MC3E). The profiling radars were deployed in Northern Oklahoma at the DOE Atmospheric Radiation Mission (ARM) Southern Great Plans (SGP) Central Facility from 22 April through 6 June 2011. NOAA deployed three instruments: a Parsivel disdrometer, a 2.8-GHz profiler, and a 449-MHz profiler. The parasivel provided surface estimates of the raindrop size distribution and is the reference used to absolutely calibrate the 2.8 GHz profiler. The 2.8-GHz profiler provided unattenuated reflectivity profiles of the precipitation. The 449-MHz profiler provided estimates of the vertical air motion during precipitation from near the surface to just below the freezing level. By using the combination of 2.8-GHz and 449-MHz profiler observations, vertical profiles of raindrop size distributions can be retrieved. The profilers are often reference by their frequency band: the 2.8-GHz profiler operates in the S-band and the 449-MHz profiler operates in the UHF band. The raw observations are available as well as calibrated spectra and moments. This document describes how the instruments were deployed, how the data was collected, and the format of the archived data.

Christopher Williams

210

Cloud computing beyond objects: seeding the cloud  

Science Conference Proceedings (OSTI)

Cloud computing is an emerging computing milieu which dynamically enables scalable and virtually unlimited resources. This panel will discuss emerging tools, skills and technologies that will ""seed the cloud"" - enabling improved interoperability, security, ... Keywords: cloud computing, skills, technologies, tools

Steven Fraser; Robert Biddle; Scott Jordan; Kate Keahey; Bob Marcus; E. Michael Maximilien; Dave Thomas

2009-10-01T23:59:59.000Z

211

Ash cloud aviation advisories  

SciTech Connect

During the recent (12--22 June 1991) Mount Pinatubo volcano eruptions, the US Air Force Global Weather Central (AFGWC) requested assistance of the US Department of Energy`s Atmospheric Release Advisory Capability (ARAC) in creating volcanic ash cloud aviation advisories for the region of the Philippine Islands. Through application of its three-dimensional material transport and diffusion models using AFGWC meteorological analysis and forecast wind fields ARAC developed extensive analysis and 12-hourly forecast ash cloud position advisories extending to 48 hours for a period of five days. The advisories consisted of ``relative`` ash cloud concentrations in ten layers (surface-5,000 feet, 5,000--10,000 feet and every 10,000 feet to 90,000 feet). The ash was represented as a log-normal size distribution of 10--200 {mu}m diameter solid particles. Size-dependent ``ashfall`` was simulated over time as the eruption clouds dispersed. Except for an internal experimental attempt to model one of the Mount Redoubt, Alaska, eruptions (12/89), ARAC had no prior experience in modeling volcanic eruption ash hazards. For the cataclysmic eruption of 15--16 June, the complex three-dimensional atmospheric structure of the region produced dramatically divergent ash cloud patterns. The large eruptions (> 7--10 km) produced ash plume clouds with strong westward transport over the South China Sea, Southeast Asia, India and beyond. The low-level eruptions (< 7 km) and quasi-steady-state venting produced a plume which generally dispersed to the north and east throughout the support period. Modeling the sequence of eruptions presented a unique challenge. Although the initial approach proved viable, further refinement is necessary and possible. A distinct need exists to quantify eruptions consistently such that ``relative`` ash concentrations relate to specific aviation hazard categories.

Sullivan, T.J.; Ellis, J.S. [Lawrence Livermore National Lab., CA (United States); Schalk, W.W.; Nasstrom, J.S. [EG and G, Inc., Pleasanton, CA (United States)

1992-06-25T23:59:59.000Z

212

The Effect of Cloud Type on Earth's Energy Balance: Global Analysis  

Science Conference Proceedings (OSTI)

The role of fractional area coverage by cloud types in the energy balance of the earth is investigated through joint use of International Satellite Cloud Climatology Project (ISCCP) C1 cloud data and Earth Radiation Budget Experiment (ERBE) ...

Dennis L. Hartmann; Maureen E. Ockert-Bell; Marc L. Michelsen

1992-11-01T23:59:59.000Z

213

In Situ Chemical Characterization of Aged Biomass-Burning Aerosols Impacting Cold Wave Clouds  

Science Conference Proceedings (OSTI)

During the Ice in Clouds Experiment–Layer Clouds (ICE-L), aged biomass-burning particles were identified within two orographic wave cloud regions over Wyoming using single-particle mass spectrometry and electron microscopy. Using a suite of ...

Kerri A. Pratt; Andrew J. Heymsfield; Cynthia H. Twohy; Shane M. Murphy; Paul J. DeMott; James G. Hudson; R. Subramanian; Zhien Wang; John H. Seinfeld; Kimberly A. Prather

2010-08-01T23:59:59.000Z

214

The Sensitivity of the Outgoing Longwave Radiation to Surface Temperature: Modeling the Opacity Feedback and Experiments with a Variable Cloud-Top Temperature Provision  

Science Conference Proceedings (OSTI)

An efficient longwave scheme for climate models originally suggested by Sasamori is modified to correctly simulate the water vapor-temperature feedback mechanism. It is found that the modified scheme with a fixed cloud-top altitude (FCA) ...

Binyamin U. Neeman; Joachim H. Joseph; George Ohring

1987-10-01T23:59:59.000Z

215

The Pre-Depression Investigation of Cloud-Systems in the Tropics (PREDICT) Experiment: Scientific Basis, New Analysis Tools, and Some First Results  

Science Conference Proceedings (OSTI)

The principal hypotheses of a new model of tropical cyclogenesis, known as the marsupial paradigm, were tested in the context of Atlantic tropical disturbances during the National Science Foundation (NSF)-sponsored Pre-Depression Investigation of Cloud ...

Michael T. Montgomery; Christopher Davis; Timothy Dunkerton; Zhuo Wang; Christopher Velden; Ryan Torn; Sharanya J. Majumdar; Fuqing Zhang; Roger K. Smith; Lance Bosart; Michael M. Bell; Jennifer S. Haase; Andrew Heymsfield; Jorgen Jensen; Teresa Campos; Mark A. Boothe

2012-02-01T23:59:59.000Z

216

The Impact of Aircraft Dropsonde and Satellite Wind Data on Numerical Simulations of Two Landfalling Tropical Storms during the Tropical Cloud Systems and Processes Experiment  

Science Conference Proceedings (OSTI)

Dropwindsonde, Geostationary Operational Environmental Satellite-11 (GOES-11) rapid-scan atmospheric motion vectors, and NASA Quick Scatterometer (QuikSCAT) near-surface wind data collected during NASA’s Tropical Cloud Systems and Processes (TCSP)...

Zhaoxia Pu; Xuanli Li; Christopher S. Velden; Sim D. Aberson; W. Timothy Liu

2008-02-01T23:59:59.000Z

217

Effects of Stratospheric Lapse Rate on Thunderstorm Cloud-Top Structure in a Three-Dimensional Numerical Simulation. Part I: Some Basic Results of Comparative Experiments  

Science Conference Proceedings (OSTI)

An anelastic three-dimensional model is used to investigate the effects of stratospheric temperature lapse rate on cloud top height/temperature structure for strongly sheared mature isolated midlatitude thunderstorms. Three comparative ...

Robert E. Schlesinger

1988-05-01T23:59:59.000Z

218

Springtime Visibility in the Arctic  

Science Conference Proceedings (OSTI)

Since the Ptarmigan flights in the 1950s, the springtime visibility reduction in the Arctic has been identified with pollution aerosol. However, observed values of the dry aerosol extinction coefficient are too small to explain the observed ...

F. G. Meyer; J. A. Curry; C. A. Brock; L. F. Radke

1991-03-01T23:59:59.000Z

219

Synoptically Driven Arctic Winter States  

Science Conference Proceedings (OSTI)

The dense network of the Surface Heat Budget of the Arctic (SHEBA) observations is used to assess relationships between winter surface and atmospheric variables as the SHEBA site came under the influence of cyclonic and anticyclonic atmospheric ...

Kirstie Stramler; Anthony D. Del Genio; William B. Rossow

2011-03-01T23:59:59.000Z

220

Arctic Sea ice model sensitivities.  

SciTech Connect

Arctic sea ice is an important component of the global climate system and, due to feedback effects, the Arctic ice cover is changing rapidly. Predictive mathematical models are of paramount importance for accurate estimates of the future ice trajectory. However, the sea ice components of Global Climate Models (GCMs) vary significantly in their prediction of the future state of Arctic sea ice and have generally underestimated the rate of decline in minimum sea ice extent seen over the past thirty years. One of the contributing factors to this variability is the sensitivity of the sea ice state to internal model parameters. A new sea ice model that holds some promise for improving sea ice predictions incorporates an anisotropic elastic-decohesive rheology and dynamics solved using the material-point method (MPM), which combines Lagrangian particles for advection with a background grid for gradient computations. We evaluate the variability of this MPM sea ice code and compare it with the Los Alamos National Laboratory CICE code for a single year simulation of the Arctic basin using consistent ocean and atmospheric forcing. Sensitivities of ice volume, ice area, ice extent, root mean square (RMS) ice speed, central Arctic ice thickness,and central Arctic ice speed with respect to ten different dynamic and thermodynamic parameters are evaluated both individually and in combination using the Design Analysis Kit for Optimization and Terascale Applications (DAKOTA). We find similar responses for the two codes and some interesting seasonal variability in the strength of the parameters on the solution.

Peterson, Kara J.; Bochev, Pavel Blagoveston; Paskaleva, Biliana Stefanova

2010-12-01T23:59:59.000Z

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


221

A 22-Year Dataset of Surface Longwave Fluxes in the Arctic  

NLE Websites -- All DOE Office Websites (Extended Search)

22-Year Dataset of Surface Longwave Fluxes 22-Year Dataset of Surface Longwave Fluxes in the Arctic J. Francis and J. Secora Institute of Marine and Coastal Sciences Rutgers University New Brunswick, New Jersey Abstract Downwelling longwave fluxes (DLFs) over the Arctic surface have been generated from 22.5 years of radiances and retrievals from the TIROS (television and infrared observation satellite) operational vertical sounder (TOVS). The flux retrieval algorithm has been validated and improved using surface- based radiation and cloud observations from the Atmospheric Radiation Measurement (ARM) North Slope of Alaska (NSA) site in Barrow, Alaska, and from the Surface Heat Balance of the Arctic (SHEBA) field program (1997-98) in the Beaufort Sea. The DLF product is presented on a 100 x

222

Observations of Marine Stratocumulus Clouds During FIRE  

Science Conference Proceedings (OSTI)

During June and July 1987, a major collaborative experiment (part of The First ISCCP [International Satellite Cloud Climatology Project] Regional Experiment (FIRE) took place off the coast of California to study the extensive fields of ...

Bruce A. Albrecht; David A. Randall; Stephen Nicholls

1988-06-01T23:59:59.000Z

223

A TWP-ICE High-Level Cloud Case Study  

NLE Websites -- All DOE Office Websites (Extended Search)

A TWP-ICE High-Level Cloud Case Study Mace, Gerald University of Utah Category: Field Campaigns The Tropical Warm Pool International Cloud Experiment (TWP ICE) was conducted near...

224

Longwave Cloud Radiative Forcing as Determined from Nimbus-7 Observations  

Science Conference Proceedings (OSTI)

Collocated and coincident cloud and outgoing longwave radiation observations taken by experiments on board the Nimbus-7 satellite have been used to infer the daytime longwave cloud-radiative forcing. Through the specification of a time-series of ...

Philip E. Ardanuy; Larry L. Stowe; Arnold Gruber; Mitchell Weiss; Craig S. Long

1989-08-01T23:59:59.000Z

225

Combustion Organic Aerosol as Cloud Condensation Nuclei in Ship Tracks  

Science Conference Proceedings (OSTI)

Polycyclic aromatic hydrocarbons (PAHs) have been sampled in marine stratiform clouds to identify the contribution of anthropogenic combustion emissions in activation of aerosol to cloud droplets. The Monterey Area Ship Track experiment provided ...

Lynn M. Russell; Kevin J. Noone; Ronald J. Ferek; Robert A. Pockalny; Richard C. Flagan; John H. Seinfeld

2000-08-01T23:59:59.000Z

226

Spectral Density of Cloud Liquid Water Content at High Frequencies  

Science Conference Proceedings (OSTI)

Aircraft measurements of liquid water content (LWC) made at sampling frequencies of 1 and 2 kHz with a particle volume monitor (PVM) probe from horizontal traverses in stratocumulus clouds during the Southern Ocean Cloud Experiment and cumulus ...

H. Gerber; J. B. Jensen; A. B. Davis; A. Marshak; W. J. Wiscombe

2001-03-01T23:59:59.000Z

227

Confronting Models with Data: The GEWEX Cloud Systems Study  

Science Conference Proceedings (OSTI)

The Global Energy and Water Cycle Experiment (GEWEX) Cloud System Study (GCSS) was organized to promote the development of improved parameterizations of cloud systems for use in climate and numerical weather prediction models, with an emphasis on ...

David Randall; Steven Krueger; Christopher Bretherton; Judith Curry; Peter Duynkerke; Mitchell Moncrieff; Brian Ryan; David Starr; Martin Miller; William Rossow; George Tselioudis; Bruce Wielicki

2003-04-01T23:59:59.000Z

228

Deployment of a Tethered-Balloon System for Microphysics and Radiative Measurements in Mixed-Phase Clouds at Ny-Ĺlesund and South Pole  

Science Conference Proceedings (OSTI)

A tethered-balloon system capable of making microphysical and radiative measurements in clouds is described and examples of measurements in boundary layer stratus clouds in the Arctic and at the South Pole are presented. A 43-m3 helium-filled ...

R. Paul Lawson; Knut Stamnes; Jakob Stamnes; Pat Zmarzly; Jeff Koskuliks; Chris Roden; Qixu Mo; Michael Carrithers; Geoffrey L. Bland

2011-05-01T23:59:59.000Z

229

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

Science Conference Proceedings (OSTI)

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

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

2010-09-28T23:59:59.000Z

230

Cloud Computing Operations Research  

Science Conference Proceedings (OSTI)

This paper argues that the cloud computing industry faces many decision problems where operations research OR could add tremendous value. To this end, we provide an OR perspective on cloud computing in three ways. First, we compare the cloud computing ... Keywords: cloud IT, cloud computing, green IT, operations research, supply chain

Ilyas Iyoob, Emrah Zarifoglu, A. B. Dieker

2013-06-01T23:59:59.000Z

231

Cloud Condensation Nuclei  

Science Conference Proceedings (OSTI)

The state of knowledge of the particles upon which liquid droplets condense to form atmospheric water clouds is presented. The realization of cloud condensation nuclei (CCN) as a distinct aerosol subset originated with the cloud microphysical ...

James G. Hudson

1993-04-01T23:59:59.000Z

232

Forecasting of Supercooled Clouds  

Science Conference Proceedings (OSTI)

Using parameterizations of cloud microphysics, a technique to forecast supercooled cloud events is suggested. This technique can be coupled on the mesoscale with a prognostic equation for cloud water to improve aircraft icing forecasts. The ...

André Tremblay; Anna Glazer; Wanda Szyrmer; George Isaac; Isztar Zawadzki

1995-07-01T23:59:59.000Z

233

Polar Cloud and Surface Classification Using AVHRR Imagery: An Intercomparison of Methods  

Science Conference Proceedings (OSTI)

Six Advanced Very High-Resolution Radiometer local area coverage (AVHPR LAC) arctic scenes are classified into ten classes. These include water, solid sea ice, broken sea ice, snow-covered mountains, snow-free land, and five cloud types. Three ...

R. M. Welch; S. K. Sengupta; A. K. Goroch; P. Rabindra; N. Rangaraj; M. S. Navar

1992-05-01T23:59:59.000Z

234

Stratocumulus Cloud Field Reflected Fluxes: The Effect of Cloud Shape  

Science Conference Proceedings (OSTI)

Reflected fluxes are calculated for stratocumulus cloud fields as a function of sky cover, cloud aspect ratio, and cloud shape. Cloud liquid water volume is held invariant as cloud shape is varied so that the results can be utilized more ...

R. M. Welch; B. A. Wielicki

1984-11-01T23:59:59.000Z

235

The Necklace around the Arctic Arctic indigenous peoples  

E-Print Network (OSTI)

national choir). #12;The economies of the Arctic settlements invariably involve fish, oil or gas: natural in the 1002 area. This work was undertaken by a private exploration firm and funded by a group of oil exploration apparently began abruptly in A.D. 793 with an attack on Lindesfarne, an island off the NE

236

Glossary Term - Cloud Chamber  

NLE Websites -- All DOE Office Websites (Extended Search)

Ceres Previous Term (Ceres) Glossary Main Index Next Term (Composition of the Earth's Atmosphere) Composition of the
Earth's Atmosphere Cloud Chamber A cloud chamber showing the...

237

ARM - Measurement - Cloud phase  

NLE Websites -- All DOE Office Websites (Extended Search)

property that captures the state o f the hydrometeors within a cloud (liquid, ice, or mixed-phase). This is distinct from cloud type that involves property descriptors...

238

Nonhydrostatic icosahedral atmospheric model (NICAM) for global cloud resolving simulations  

Science Conference Proceedings (OSTI)

A new type of ultra-high resolution atmospheric global circulation model is developed. The new model is designed to perform ''cloud resolving simulations'' by directly calculating deep convection and meso-scale circulations, which play key roles not ... Keywords: Aqua-planet experiments, Atmospheric general circulation models, Cloud clusters, Cloud resolving model, Icosahedral grids, Nonhydrostatic model

M. Satoh; T. Matsuno; H. Tomita; H. Miura; T. Nasuno; S. Iga

2008-03-01T23:59:59.000Z

239

The Influence of Local Feedbacks and Northward Heat Transport on the Equilibrium Arctic Climate Response to Increased Greenhouse Gas Forcing  

Science Conference Proceedings (OSTI)

This study uses coupled climate model experiments to identify the influence of atmospheric physics [Community Atmosphere Model, versions 4 and 5 (CAM4; CAM5)] and ocean model complexity (slab ocean, full-depth ocean) on the equilibrium Arctic ...

Jennifer E. Kay; Marika M. Holland; Cecilia M. Bitz; Edward Blanchard-Wrigglesworth; Andrew Gettelman; Andrew Conley; David Bailey

2012-08-01T23:59:59.000Z

240

Evaluation of Cloud Type Occurrences and Radiative Forcings Simulated by a Cloud Resolving Model Using Observations from Sa...  

NLE Websites -- All DOE Office Websites (Extended Search)

Cloud Type Occurrences Cloud Type Occurrences and Radiative Forcings Simulated by a Cloud Resolving Model Using Observations from Satellite and Cloud Radar Y. Luo and S. K. Krueger University of Utah Salt Lake City, Utah Introduction Because of both the various effects clouds exert on the earth-atmospheric system and the cloud feedback, correct representations of clouds in numerical models are critical for accurate climate modeling and weather forecast. Unfortunately, determination of clouds and their radiative feedback processes is still the weakest component of current general circulation models (e.g., Senior and Mitchell 1993, Cess et al. 1996). Using radiative fluxes at the top of atmosphere (TOA) available from satellite observations made by the Earth Radiation Budget Experiment (ERBE; Barkstrom 1984), one could assess cloud radiative effects

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


241

Short-Term Climatic Variability of the Arctic  

Science Conference Proceedings (OSTI)

The circulation of the Arctic atmosphere undergoes large fluctuations about its monthly and annual means. The statistics of Arctic sea level pressure and temperature are evaluated in order to place Arctic atmospheric variability into the context ...

John E. Walsh; William L. Chapman

1990-02-01T23:59:59.000Z

242

A Potential Role for Immersion Freezing in Arctic Mixed-Phase Stratus Gijs de Boer,Edwin W.Eloranta,Tempei Hashino,and Gregory J.Tripoli  

E-Print Network (OSTI)

to a dominant factor controlling the lifecycle of Arctic mixed-phase clouds. To date, our understanding of ice Stratus from M-PACE Mixed-Phase Layer Ice Precipitation "Bursts" Time (UT) Altitude(km) Lidar backscatter. - Additionally, Shupe illustrated that ice water content and liquid water content seem to vary in phase with each

Eloranta, Edwin W.

243

Latitudinal distribution of the recent Arctic warming  

Science Conference Proceedings (OSTI)

Increasing Arctic temperature, disappearance of Arctic sea ice, melting of the Greenland ice sheet, sea level rise, increasing strength of Atlantic hurricanes are these impending climate catastrophes supported by observations? Are the recent data really unprecedented during the observational records? Our analysis of Arctic temperature records shows that the Arctic and temperatures in the 1930s and 1940s were almost as high as they are today. We argue that the current warming of the Arctic region is affected more by the multi-decadal climate variability than by an increasing concentration of carbon dioxide. Unfortunately, none of the existing coupled Atmosphere-Ocean General Circulation Models used in the IPCC 2007 cIimate change assessment is able to reproduce neither the observed 20th century Arctic cIimate variability nor the latitudinal distribution of the warming.

Chylek, Petr [Los Alamos National Laboratory; Lesins, Glen K [DALLHOUSIE UNIV.; Wang, Muyin [UNIV OF WASHINGTON

2010-12-08T23:59:59.000Z

244

Potential Oil Production from the Coastal Plain of the Arctic ...  

U.S. Energy Information Administration (EIA)

1. Overview of the Arctic National Wildlife Refuge. Background. The Arctic National Wildlife Refuge (ANWR) 1002 Area of the Alaska North Slope represents an area ...

245

The ecology of Arctic cod (Boreogadus saida) and interactions with seabirds, seals, and whales in the Canadian Arctic.  

E-Print Network (OSTI)

??This thesis investigates the foraging of Arctic cod (Boreogadus saida) and its predators during the summer in the Canadian Arctic. Findings included the identification of… (more)

Matley, Jordan

2012-01-01T23:59:59.000Z

246

The Optical Gravitational Lensing Experiment. The OGLE-III Catalog of Variable Stars. VII. Classical Cepheids in the Small Magellanic Cloud  

E-Print Network (OSTI)

The seventh part of the OGLE-III Catalog of Variable Stars (OIII-CVS) consists of 4630 classical Cepheids in the Small Magellanic Cloud (SMC). The sample includes 2626 fundamental-mode (F), 1644 first-overtone (1O), 83 second-overtone (2O), 59 double-mode F/1O, 215 double-mode 1O/2O, and 3 triple-mode classical Cepheids. For each object basic parameters, multi-epoch VI photometry collected within 8 or 13 years of observations, and finding charts are provided in the OGLE Internet archive. We present objects of particular interest: exceptionally numerous sample of single-mode second-overtone pulsators, five double Cepheids, two Cepheids with eclipsing variations superimposed on the pulsation light curves. At least 139 first-overtone Cepheids exhibit low-amplitude secondary variations with periods in the range 0.60-0.65 of the primary ones. These stars populate three distinct sequences in the Petersen diagram. The origin of this secondary modulation is still unknown. Contrary to the Large Magellanic Cloud (LMC) ...

Soszynski, I; Udalski, A; Szymanski, M K; Kubiak, M; Pietrzynski, G; Wyrzykowski, L; Szewczyk, O; Ulaczyk, K

2010-01-01T23:59:59.000Z

247

turner_poster.arctic_bbhrp.ppt  

NLE Websites -- All DOE Office Websites (Extended Search)

into different classes: "single-layer" and "double-layer" clouds of liquid-only, mixed-phase, and ice-only clouds. * A cloud layer is a vertically continuous region of the...

248

Application of Stochastic Radiative Transfer Theory to the ARM Cloud-Radiative Parameterization Problem  

Science Conference Proceedings (OSTI)

This project had two primary goals: (1) development of stochastic radiative transfer as a parameterization that could be employed in an AGCM environment, and (2) exploration of the stochastic approach as a means for representing shortwave radiative transfer through mixed-phase layer clouds. To achieve these goals, climatology of cloud properties was developed at the ARM CART sites, an analysis of the performance of the stochastic approach was performed, a simple stochastic cloud-radiation parameterization for an AGCM was developed and tested, a statistical description of Arctic mixed phase clouds was developed and the appropriateness of stochastic approach for representing radiative transfer through mixed-phase clouds was assessed. Significant progress has been made in all of these areas and is detailed in the final report.

Dana E. Veron

2012-04-09T23:59:59.000Z

249

Analysis of Aircraft, Radiosonde, and Radar Observations in Cirrus Clouds Observed during FIRE II: The Interactions between Environmental Structure, Turbulence, and Cloud Microphysical Properties  

Science Conference Proceedings (OSTI)

Ways to determine the turbulence intensity and the horizontal variability in cirrus clouds have been investigated using First International Satellite Cloud Climatology Project (ISCCP) Regional Experiment II aircraft, radiosonde, and radar data. ...

Samantha A. Smith; Anthony D. DelGenio

2001-03-01T23:59:59.000Z

250

Global Circuit Model with Clouds  

Science Conference Proceedings (OSTI)

Cloud data from the International Satellite Cloud Climatology Project (ISCCP) database have been introduced into the global circuit model developed by Tinsley and Zhou. Using the cloud-top pressure data and cloud type information, the authors ...

Limin Zhou; Brian A. Tinsley

2010-04-01T23:59:59.000Z

251

Arctic Inversion Strength in Climate Models  

Science Conference Proceedings (OSTI)

Recent work indicates that climate models have a positive bias in the strength of the wintertime low-level temperature inversion over the high-latitude Northern Hemisphere. It has been argued this bias leads to underestimates of the Arctic’s ...

Brian Medeiros; Clara Deser; Robert A. Tomas; Jennifer E. Kay

2011-09-01T23:59:59.000Z

252

Cloud Computing Forum & Workshop II  

Science Conference Proceedings (OSTI)

Cloud Computing Forum & Workshop II. Purpose: On May 20, 2010, NIST hosted the first Cloud Computing Forum & Workshop. ...

2013-08-07T23:59:59.000Z

253

ISCCP Cloud Algorithm Intercomparison  

Science Conference Proceedings (OSTI)

The International Satellite Cloud Climatology Project (ISCCP) will provide a uniform global climatology of satellite-measured radiances and derive an experimental climatology of cloud radiative properties from these radiances. A pilot study to ...

W. B. Rossow; F. Mosher; E. Kinsella; A. Arking; M. Desbois; E. Harrison; P. Minnis; E. Ruprecht; G. Seze; C. Simmer; E. Smith

1985-09-01T23:59:59.000Z

254

Automated cloud resource orchestration  

Science Conference Proceedings (OSTI)

Realizing Infrastructure-as-a-Service (IaaS) cloud requires a control platform for orchestrating the provisioning, configuration, management and decommissioning of a distributed set of diverse cloud resources (i.e., compute, storage, network) serving ...

Changbin Liu / Boon Thau Loo

2012-01-01T23:59:59.000Z

255

ARM - Measurement - Cloud type  

NLE Websites -- All DOE Office Websites (Extended Search)

type ARM Data Discovery Browse Data Comments? We would love to hear from you Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Cloud type Cloud type such as...

256

Entrainment in Cumulus Clouds  

Science Conference Proceedings (OSTI)

Entrainment of dry air into cumulus clouds influences the development of the clouds in a major way. The many aspects of the entrainment process are examined in this paper by critically reviewing the literature from the time when investigations ...

Alan M. Blyth

1993-04-01T23:59:59.000Z

257

Clouds in Tropical Cyclones  

Science Conference Proceedings (OSTI)

Clouds within the inner regions of tropical cyclones are unlike those anywhere else in the atmosphere. Convective clouds contributing to cyclogenesis have rotational and deep intense updrafts but tend to have relatively weak downdrafts. Within ...

Robert A. Houze Jr.

2010-02-01T23:59:59.000Z

258

North Australian Cloud Lines  

Science Conference Proceedings (OSTI)

A satellite classification and climatology of propagating mesoscale cloud fines in northern Australia is presented. These cloud fines range from long, narrow lines of shallow convection to extensive deep convective squall lines with mesoscale ...

W. Drosdowsky; G. J. Holland

1987-11-01T23:59:59.000Z

259

Clouds in Tropical Cyclones  

Science Conference Proceedings (OSTI)

Clouds within the inner regions of tropical cyclones are unlike those anywhere else in the atmosphere. Convective clouds contributing to cyclogenesis have rotational and deep intense updrafts but tend to have relatively weak downdrafts. Within the ...

Robert A. Houze Jr.

2010-02-01T23:59:59.000Z

260

Phenomenological Description of Tropical Clouds Using CloudSat Cloud Classification  

Science Conference Proceedings (OSTI)

Two years of tropical oceanic cloud observations are analyzed using the operational CloudSat cloud classification product and Cloud–Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) lidar. Relationships are examined between ...

Ali Behrangi; Terry Kubar; Bjorn Lambrigtsen

2012-10-01T23:59:59.000Z

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


261

Computing and Partitioning Cloud Feedbacks Using Cloud Property Histograms. Part I: Cloud Radiative Kernels  

Science Conference Proceedings (OSTI)

This study proposes a novel technique for computing cloud feedbacks using histograms of cloud fraction as a joint function of cloud-top pressure (CTP) and optical depth (?). These histograms were generated by the International Satellite Cloud ...

Mark D. Zelinka; Stephen A. Klein; Dennis L. Hartmann

2012-06-01T23:59:59.000Z

262

Cloud Computing at NERSC  

NLE Websites -- All DOE Office Websites (Extended Search)

Cloud Computing Energy Efficient Computing Exascale Computing Performance & Monitoring Tools Petascale Initiative Science Gateway Development Storage and IO Technologies Testbeds...

263

Storm Peak Lab Cloud Property Validation  

NLE Websites -- All DOE Office Websites (Extended Search)

Storm Peak Lab Cloud Storm Peak Lab Cloud Property Validation Experiment (STORMVEX) Operated by the Atmospheric Radiation Measurement (ARM) Climate Research Facility for the U.S. Department of Energy, the second ARM Mobile Facility (AMF2) begins its inaugural deployment November 2010 in Steamboat Springs, Colorado, for the Storm Peak Lab Cloud Property Validation Experiment, or STORMVEX. For six months, the comprehensive suite of AMF2 instruments will obtain measurements of cloud and aerosol properties at various sites below the heavily instrumented Storm Peak Lab, located on Mount Werner at an elevation of 3220 meters. The correlative data sets that will be created from AMF2 and Storm Peak Lab will equate to between 200 and 300 in situ aircraft flight hours in liquid, mixed phase, and precipitating

264

Rope Cloud over Land  

Science Conference Proceedings (OSTI)

Satellite imagery is used to document several rope clouds over the southeastern Unites States. Surface and upper-air data are examined for one of the rope clouds and possible reasons for the development and maintenance of this type cloud line are ...

Von S. Woods

1983-03-01T23:59:59.000Z

265

User Centric Community Clouds  

Science Conference Proceedings (OSTI)

With the evolution in cloud technologies, users are becoming acquainted with seamless service provision. Nevertheless, clouds are not a user centric technology, and users become completely dependent on service providers. We propose a novel concept for ... Keywords: Cloud infrastructure, Identity management, User-centric systems

Joăo Paulo Barraca; Alfredo Matos; Rui L. Aguiar

2011-05-01T23:59:59.000Z

266

The Optical Gravitational Lensing Experiment. The OGLE-III Catalog of Variable Stars. III. RR Lyrae Stars in the Large Magellanic Cloud  

E-Print Network (OSTI)

The third part of the OGLE-III Catalog of Variable Stars comprises 24906 RR Lyr stars in the Large Magellanic Cloud (LMC). This sample consist of 17693 fundamental-mode (RRab), 4958 first-overtone (RRc), 986 double-mode (RRd) and 1269 suspected second-overtone (RRe) pulsators. 66 objects are foreground Galactic RR Lyr stars. The catalog data include basic photometric and astrometric properties of the RR Lyr stars, multi-epoch VI photometry and finding charts. We detected one new RR Lyr star with additional eclipsing variations. The spatial distribution of RR Lyr stars in the LMC is distinctly non-spherical and it is elongated in the same direction as the LMC bar. The basic statistical features of RR Lyr stars in the LMC are provided. The apparent V-band magnitudes for RRab stars have the modal value at 19.36 mag, and for overtone RR Lyr stars it is about 19.32 mag. The mean periods for RRab, RRc and RRe stars are 0.576, 0.337 and 0.270 days, respectively.

Soszynski, I; Szymanski, M K; Kubiak, M; Pietrzynski, G; Wyrzykowski, L; Szewczyk, O; Ulaczyk, K; Poleski, R

2009-01-01T23:59:59.000Z

267

The Optical Gravitational Lensing Experiment. The OGLE-III Catalog of Variable Stars. IX. RR Lyrae Stars in the Small Magellanic Cloud  

E-Print Network (OSTI)

The ninth part of the OGLE-III Catalog of Variable Stars (OIII-CVS) comprises RR Lyrae stars in the Small Magellanic Cloud (SMC). Our sample consists of 2475 variables, of which 1933 pulsate in the fundamental mode (RRab), 175 are the first overtone pulsators (RRc), 258 oscillate simultaneously in both modes (RRd) and 109 stars are suspected second-overtone pulsators (RRe). 30 objects are Galactic RR Lyr stars seen in the foreground of the SMC. We discuss some statistical features of the sample. Period distributions show distinct differences between SMC and LMC populations of RR Lyr variables, with the SMC stars having on average longer periods. The mean periods for RRab, RRc and RRe stars are 0.596, 0.366 and 0.293 days, respectively. The mean apparent magnitudes of RRab stars are equal to 19.70 mag in the V band and 19.12 mag in the I band. Spatial distribution of RR Lyr stars shows that the halo of the SMC is roughly round in the sky, however the density map reveals two maxima near the center of the SMC. F...

Soszynski, I; Szymanski, M K; Kubiak, M; Pietrzynski, G; Wyrzykowski, L; Ulaczyk, K; Poleski, R

2010-01-01T23:59:59.000Z

268

Turbulent molecular clouds  

E-Print Network (OSTI)

Stars form within molecular clouds but our understanding of this fundamental process remains hampered by the complexity of the physics that drives their evolution. We review our observational and theoretical knowledge of molecular clouds trying to confront the two approaches wherever possible. After a broad presentation of the cold interstellar medium and molecular clouds, we emphasize the dynamical processes with special focus to turbulence and its impact on cloud evolution. We then review our knowledge of the velocity, density and magnetic fields. We end by openings towards new chemistry models and the links between molecular cloud structure and star--formation rates.

Hennebelle, Patrick

2012-01-01T23:59:59.000Z

269

Polar Cloud Climatologies from ISCCP C2 and D2 Datasets  

Science Conference Proceedings (OSTI)

A deterministic radiative transfer model along with data from the International Satellite Cloud Climatology Project (ISCCP) and the Earth Radiation Budget Experiment (ERBE) were used to examine long-term mean monthly cloud climatologies for the ...

N. Hatzianastassiou; N. Cleridou; I. Vardavas

2001-09-01T23:59:59.000Z

270

Ship-Based Observations of the Diurnal Cycle of Southeast Pacific Marine Stratocumulus Clouds and Precipitation  

Science Conference Proceedings (OSTI)

The diurnal cycle of marine stratocumulus in cloud-topped boundary layers is examined using ship-based meteorological data obtained during the 2008 VAMOS Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx). The high temporal and ...

Casey D. Burleyson; Simon P. de Szoeke; Sandra E. Yuter; Matt Wilbanks; W. Alan Brewer

271

The Effect of Cloud Type on Earth's Energy Balance: Results for Selected Regions  

Science Conference Proceedings (OSTI)

International Satellite Cloud Climatology Project (ISCCP) Cl cloud information is compared with planetary albedo, outgoing longwave radiation (OLR), and net radiation measured at the top of the atmosphere by the Earth Radiation Budget Experiment (...

Maureen E. Ockert-Bell; Dennis L. Hartmann

1992-10-01T23:59:59.000Z

272

Dynamical Characteristics of Cirrus Clouds from Aircraft and Radar Observations in Micro and Meso-? Scales  

Science Conference Proceedings (OSTI)

Cirrus clouds that formed on 26 November and 6 December 1991 during the First International Satellite Cloud Climatology Project Regional Experiment (FIRE) II, which took place over the Kansas region. are studied because of significant dynamic ...

I. Gultepe; D. O'C. Starr; A. J. Heymsfield; T. Uttal; T. P. Ackerman; D. L. WestPhal

1995-12-01T23:59:59.000Z

273

Microphysical and Radar Observations of Seeded and Nonseeded Continental Cumulus Clouds  

Science Conference Proceedings (OSTI)

Controlled cloud seeding experiments were conducted near Bethlehem, South Africa during the summer of 1984–85. The experimental unit was the semi-isolated cumulus congestus cloud. Microphysical measurements were obtained by three instrumented ...

T. W. Krauss; R. T. Bruintjes; J. Verlinde

1987-05-01T23:59:59.000Z

274

The Sensitivity of Convective Initiation to the Lapse Rate of the Active Cloud-Bearing Layer  

Science Conference Proceedings (OSTI)

Numerical experiments are conducted using an idealized cloud-resolving model to explore the sensitivity of deep convective initiation (DCI) to the lapse rate of the active cloud-bearing layer [ACBL; the atmospheric layer above the level of free ...

Adam L. Houston; Dev Niyogi

2007-09-01T23:59:59.000Z

275

The Vertical Profile of Liquid and Ice Water Content in Midlatitude Mixed-Phase Altocumulus Clouds  

Science Conference Proceedings (OSTI)

The microphysical properties of mixed-phase altocumulus clouds are investigated using in situ airborne measurements acquired during the ninth Cloud Layer Experiment (CLEX-9) over a midlatitude location. Approximately ? of the sampled profiles are ...

Lawrence D. Carey; Jianguo Niu; Ping Yang; J. Adam Kankiewicz; Vincent E. Larson; Thomas H. Vonder Haar

2008-09-01T23:59:59.000Z

276

On the Observed Near Cancellation between Longwave and Shortwave Cloud Forcing in Tropical Regions  

Science Conference Proceedings (OSTI)

Observations based on Earth Radiation Budget Experiment (ERBE) satellite data indicate that there is a near cancellation between tropical longwave and shortwave cloud forcing in regions of deep convective activity. Cloud forcing depends on both ...

J. T. Kiehl

1994-04-01T23:59:59.000Z

277

Factors Determining the Impact of Aerosols on Surface Precipitation from Clouds: An Attempt at Classification  

Science Conference Proceedings (OSTI)

The simulation of the dynamics and the microphysics of clouds observed during the Large-Scale Biosphere–Atmosphere Experiment in Amazonia—Smoke, Aerosols, Clouds, Rainfall, and Climate (LBA–SMOCC) campaign, as well as extremely continental and ...

A. P. Khain; N. BenMoshe; A. Pokrovsky

2008-06-01T23:59:59.000Z

278

Response of the Wintertime Northern Hemisphere Atmospheric Circulation to Current and Projected Arctic Sea Ice Decline: A Numerical Study with CAM5  

Science Conference Proceedings (OSTI)

The wintertime Northern Hemisphere (NH) atmospheric circulation response to current (2007–12) and projected (2080–99) Arctic sea ice decline is examined with the latest version of the Community Atmospheric Model (CAM5). The numerical experiments ...

Yannick Peings; Gudrun Magnusdottir

2014-01-01T23:59:59.000Z

279

Experiences  

NLE Websites -- All DOE Office Websites (Extended Search)

Experiences Experiences with 100Gbps Network Applications Mehmet Balman, Eric Pouyoul, Yushu Yao, E. Wes Bethel Burlen Loring, Prabhat, John Shalf, Alex Sim, and Brian L. Tierney Lawrence Berkeley National Laboratory One Cyclotron Road Berkeley, CA, 94720, USA {mbalman,epouyoul,yyao,ewbethel,bloring,prabhat,jshalf,asim,btierney}@lbl.gov ABSTRACT 100Gbps networking has finally arrived, and many research and educational institutions have begun to deploy 100Gbps routers and services. ESnet and Internet2 worked together to make 100Gbps networks available to researchers at the Supercomputing 2011 con- ference in Seattle Washington. In this paper, we describe two of the first applications to take advantage of this network. We demon- strate a visualization application that enables remotely located sci- entists to gain insights from large datasets. We also demonstrate climate

280

Cloud displays for mobile users in a display cloud  

Science Conference Proceedings (OSTI)

The display cloud model allows users to select local and remote programmable displays, and add them to a user specific cloud display where the user can arrange them freely. On a cloud display, the abstraction representing remote graphical content is ... Keywords: cloud displays, display clouds, ubiquitous displays

Lars Tiede; John Markus Bjřrndalen; Otto J. Anshus

2013-02-01T23:59:59.000Z

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


281

Cloud Properties Working Group Low Clouds Update  

NLE Websites -- All DOE Office Websites (Extended Search)

Cloud Properties Working Group Cloud Properties Working Group Low Clouds Update Low Clouds Update Jennifer Comstock Jennifer Comstock Dave Turner Dave Turner Andy Andy Vogelmann Vogelmann Instruments Instruments 90/150 GHz microwave radiometer 90/150 GHz microwave radiometer Deployed during COPS AMF Deployed during COPS AMF Exploring calibration w/ DPR ( Exploring calibration w/ DPR ( Crewell Crewell & & L L ö ö hnert hnert ) ) See COPS Breakout, Wednesday evening See COPS Breakout, Wednesday evening 183 GHz (GVR) deployed at the NSA 183 GHz (GVR) deployed at the NSA Neural network algorithm to retrieve PWV & LWP (Maria Neural network algorithm to retrieve PWV & LWP (Maria Cadeddu Cadeddu ) ) Potential VAP candidate (RPWG) Potential VAP candidate (RPWG)

282

Misers gold dust collection and cloud characterization  

SciTech Connect

MISERS GOLD was a surface detonation of 2445 tons of ammonium nitrate-fuel oil blasting agent conducted by the Defense Nuclear Agency for a variety of research purposes. This report presents the results of an experiment designed to study the dust cloud over the 24-hour period following the detonation. The cloud was sampled by aircraft to obtain material needed to characterize the quantity of dust lofted, the source regions of the cloud, and the size, shape, and mineralogical characteristics of the particles. Elemental tracers and organic dyes were emplaced in the charge and in surrounding areas. Analyses were done by instrumental neutron activation analysis (INAA), fluorimetry, scanning electron microscopy (SEM), and energy-dispersive spectrometry (EDS). Tracer data define the source regions of the dust cloud. Extensive particle size distribution data were obtained. 12 figs.

Mason, A.S.; Finnegan, D.L.; Bayhurst, G.K.; Raymond, R. Jr.; Hagan, R.C.; Luedemann, G.; Wohletz, K.H.

1991-01-01T23:59:59.000Z

283

Arctic Ocean circulation patterns revealed by GRACE  

Science Conference Proceedings (OSTI)

Measurements of ocean bottom pressure (OBP) anomalies from the satellite mission GRACE, complemented by information from two ocean models, are used to investigate the variations and distribution of the Arctic Ocean mass from 2002 through 2011. The ...

Cecilia Peralta-Ferriz; James H. Morison; John M. Wallace; Jennifer A. Bonin; Jinlun Zhang

284

Recovery mechanisms of Arctic summer sea ice  

E-Print Network (OSTI)

[1] We examine the recovery of Arctic sea ice from prescribed ice?free summer conditions in simulations of 21st century climate in an atmosphere–ocean general circulation model. We find that ice extent recovers typically within two years. The excess oceanic heat that had built up during the ice?free summer is rapidly returned to the atmosphere during the following autumn and winter, and then leaves the Arctic partly through increased longwave emission at the top of the atmosphere and partly through reduced atmospheric heat advection from lower latitudes. Oceanic heat transport does not contribute significantly to the loss of the excess heat. Our results suggest that anomalous loss of Arctic sea ice during asinglesummerisreversible,astheice–albedo feedback is alleviated by large?scale recovery mechanisms. Hence, hysteretic threshold behavior (or a “tipping point”) is unlikely to occur during the decline of Arctic summer sea?

unknown authors

2011-01-01T23:59:59.000Z

285

Derivation of Seasonal Cloud Properties at ARM-NSA from Multispectral MODIS Data  

NLE Websites -- All DOE Office Websites (Extended Search)

Derivation of Seasonal Cloud Properties at ARM-NSA Derivation of Seasonal Cloud Properties at ARM-NSA from Multispectral MODIS Data D. A. Spangenberg Analytical Services and Materials, Inc. Hampton, Virginia P. Minnis National Aeronautics and Space Administration Langley Research Center Hampton, Virginia T. Uttal National Oceanic and Atmospheric Administration Environmental Technology Laboratory Boulder, Colorado Q. Z. Trepte and S. S.-Mack Science Applications International Corporation Hampton, Virginia Introduction Improving climate model predictions over earth's Polar Regions requires a complete knowledge of polar cloud microphysics. Over the Arctic, there is minimal contrast between the clouds and background snow surface observed in satellite data, especially for visible wavelengths. This makes it difficult to

286

BNL | Cloud Lifecycle Infrastructure  

NLE Websites -- All DOE Office Websites (Extended Search)

Cloud Life Cycle Infrastructure Cloud Life Cycle Infrastructure An important component of any long-term atmospheric measurement program is the quality control and maintenance of the datastreams from instrument systems. Further, the raw measurements from atmospheric remote sensing instrumentation are not directly useable by the majority of the scientific community. These raw measurements must be interpreted and converted to geophysical quantities that can be more readily used by a greater number of scientists to address important questions regarding the Earth's climate system. The cloud life cycle infrastructure group at BNL is led by Dr. Michael Jensen and is responsible for the development and production of cloud-related value-added products (VAPs). The cloud life cycle infrastructure group also provides mentorships for the millimeter cloud

287

BNL | Cloud Lifecycle Research  

NLE Websites -- All DOE Office Websites (Extended Search)

to be one of the major sources of uncertainty in numerical simulations of climate and weather. Improvement of the representation of clouds in numerical models requires fundamental...

288

Dispersion of Cloud Droplet Size Distributions, Cloud Parameterization...  

NLE Websites -- All DOE Office Websites (Extended Search)

National Laboratory Upton, New York Introduction Most studies of the effect of aerosols on cloud radiative properties have considered only changes in the cloud droplet...

289

Cloud Classification Before Luke Howard  

Science Conference Proceedings (OSTI)

A brief outline of the history of cloud painting prior to the first cloud classification schemes of Luke Howard and Lamarck is presented. It is shown that European painters had accurately represented most of the different cloud forms between ...

Stanely David Gedzelman

1989-04-01T23:59:59.000Z

290

Radar Reflectivity of Cumulus Clouds  

Science Conference Proceedings (OSTI)

The relationships between the radar reflectivity factor Z and significant physical cloud parameters are studied from a dataset collected with an instrumented aircraft in non- or very weakly precipitating warm clouds. The cloud droplet populations ...

Henri Sauvageot; Jilani Omar

1987-06-01T23:59:59.000Z

291

Observed Microphysical Structure of Midlevel, Mixed-Phase Clouds  

Science Conference Proceedings (OSTI)

This paper analyzes airborne measurements of six midlevel clouds observed over the Great Plains of the United States in late 1999 and early 2000 during the fifth of the Complex Layered-Cloud Experiments (CLEX-5). Data show that these innocuous-...

Robert P. Fleishauer; Vincent E. Larson; Thomas H. Vonder Haar

2002-06-01T23:59:59.000Z

292

ORNL DAAC, Arctic Tundra Flux Data, February 2002  

NLE Websites -- All DOE Office Websites (Extended Search)

atmospheric fluxes in the Arctic tundra are now available on-line. The newly released data set "Arctic Tundra Flux Study in the Kuparuk River Basin (Alaska), 1994-1996" contains...

293

Is A Sleeping Climate Giant Stirring in the Arctic?  

NLE Websites -- All DOE Office Websites (Extended Search)

Is A Sleeping Climate Giant Stirring in the Arctic? Print E-mail Is a sleeping climate giant stirring in the arctic? Wednesday, June 12, 2013 Featured by NASA a member of the U.S....

294

Development of a Regional Climate Model of the Western Arctic  

Science Conference Proceedings (OSTI)

An Arctic region climate system model has been developed to simulate coupled interactions among the atmosphere, sea ice, ocean, and land surface of the western Arctic. The atmospheric formulation is based upon the NCAR regional climate model ...

Amanda H. Lynch; William L. Chapman; John E. Walsh; Gunter Weller

1995-06-01T23:59:59.000Z

295

Arctic Climate Change as Manifest in Cyclone Behavior  

Science Conference Proceedings (OSTI)

The Arctic region has exhibited dramatic changes in recent times. Many of these are intimately tied up with synoptic activity, but little research has been undertaken on how the characteristics of Arctic cyclones have changed. This paper presents ...

Ian Simmonds; Craig Burke; Kevin Keay

2008-11-01T23:59:59.000Z

296

Comments on “Current GCMs' Unrealistic Negative Feedback in the Arctic  

Science Conference Proceedings (OSTI)

In contrast to prior studies showing a positive lapse-rate feedback associated with the Arctic inversion, Boé et al. reported that strong present-day Arctic temperature inversions are associated with stronger negative longwave feedbacks and thus ...

Felix Pithan; Thorsten Mauritsen

2013-10-01T23:59:59.000Z

297

Comments on “Current GCMs’ Unrealistic Negative Feedback in the Arctic  

Science Conference Proceedings (OSTI)

Contrasting our expectation of a positive lapse-rate feedback associated with the Arctic inversion, Boé et al. (2009) report that strong present-day Arctic temperature inversions are associated with stronger negative longwave feedbacks and thus ...

Felix Pithan; Thorsten Mauritsen

298

Tuktoyaktuk : responsive strategies for a new Arctic urbanism  

E-Print Network (OSTI)

The Canadian Arctic is facing a set of compounding crises that will drastically impact the future of its coastal frontier. At a time when climate change is having a detrimental impact on the Arctic landscape, Northern ...

Ritchot, Pamela (Pamela Rae)

2011-01-01T23:59:59.000Z

299

The Arctic Ocean Response to the North Atlantic Oscillation  

Science Conference Proceedings (OSTI)

The climatically sensitive zone of the Arctic Ocean lies squarely within the domain of the North Atlantic oscillation (NAO), one of the most robust recurrent modes of atmospheric behavior. However, the specific response of the Arctic to annual ...

R. R. Dickson; T. J. Osborn; J. W. Hurrell; J. Meincke; J. Blindheim; B. Adlandsvik; T. Vinje; G. Alekseev; W. Maslowski

2000-08-01T23:59:59.000Z

300

Cloud Computing Forum & Workshop IV  

Science Conference Proceedings (OSTI)

Cloud Computing Forum & Workshop IV. ... NIST announces the Cloud Computing Forum & Workshop IV to be held on November 2, 3 and 4, 2011. ...

2013-08-07T23:59:59.000Z

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


301

BNL | Aerosol, Cloud, Precipitation Interactions  

NLE Websites -- All DOE Office Websites (Extended Search)

Cloud-Aerosol-Precipitation Interactions Cloud-Aerosol-Precipitation Interactions Atmospheric aerosols exert important "indirect effects" on clouds and climate by serving as cloud condensation nuclei (CCN) and ice nuclei that affect cloud radiative and microphysical properties. For example, an increase in CCN increases the number concentration of droplets enhances cloud albedo, and suppresses precipitation that alters cloud coverage and lifetime. However, in the case of moist and strong convective clouds, increasing aerosols may increase precipitation and enhance storm development. Although aerosol-induced indirect effects on climate are believed to have a significant impact on global climate change, estimating their impact continues to be one of the most uncertain climate forcings.

302

Ganges valley aerosol experiment.  

Science Conference Proceedings (OSTI)

In June 2011, the Ganges Valley Aerosol Experiment (GVAX) began in the Ganges Valley region of India. The objective of this field campaign is to obtain measurements of clouds, precipitation, and complex aerosols to study their impact on cloud formation and monsoon activity in the region.

Kotamarthi, V.R.; Satheesh, S.K. (Environmental Science Division); (Indian Institute of Science, Bangalore, India)

2011-08-01T23:59:59.000Z

303

Cirrus Cloud Properties from a Cloud-Resolving Model Simulation Compared to Cloud Radar Observations  

Science Conference Proceedings (OSTI)

Cloud radar data collected at the Atmospheric Radiation Measurement (ARM) Program's Southern Great Plains site were used to evaluate the properties of cirrus clouds that occurred in a cloud-resolving model (CRM) simulation of the 29-day summer ...

Yali Luo; Steven K. Krueger; Gerald G. Mace; Kuan-Man Xu

2003-02-01T23:59:59.000Z

304

Systematic Flights Obtain Long-Term Data Set of Cloud Properties  

NLE Websites -- All DOE Office Websites (Extended Search)

Systematic Flights Obtain Long-Term Data Set of Cloud Properties Systematic Flights Obtain Long-Term Data Set of Cloud Properties Beginning in January 2009, the U.S. Department of Energy's Atmospheric Radiation Measurement (ARM) Climate Research Facility is sponsoring the first-of-its-kind long-term airborne research campaign to obtain data from low-level clouds above its Southern Great Plains (SGP) site. The five-month campaign is centered near Lamont, Oklahoma, a mid-latitude region that experiences a wide range of cloud types, including the "thin" clouds that are the focus of the campaign. Thin clouds contain so little water that the sun can be seen through them. Scientists refer to such clouds as "clouds with low-optical water depth," or CLOWD. Because these clouds are often tenuous and scattered, even some of the best

305

CONTRIBUTED Green Cloud Computing  

E-Print Network (OSTI)

widely dis- cussed, the shift in energy usage in a cloud computing model has received little attention cloud computing services typically operate. We consider energy consumption models of the transport of energy per bit also allows the results to be easily scaled to any usage level. We consider both public

Tucker, Rod

306

Cryptographic cloud storage  

Science Conference Proceedings (OSTI)

We consider the problem of building a secure cloud storage service on top of a public cloud infrastructure where the service provider is not completely trusted by the customer. We describe, at a high level, several architectures that combine recent and ...

Seny Kamara; Kristin Lauter

2010-01-01T23:59:59.000Z

307

Experimental Analysis of Task-based Energy Consumption in Cloud Computing Systems  

E-Print Network (OSTI)

this model, we have conducted extensive experiments to profile the energy consumption in cloud computingExperimental Analysis of Task-based Energy Consumption in Cloud Computing Systems Feifei Chen, John is that large cloud data centres consume large amounts of energy and produce significant carbon footprints

Schneider, Jean-Guy

308

ARM - Measurement - Cloud extinction  

NLE Websites -- All DOE Office Websites (Extended Search)

extinction extinction ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Cloud extinction The removal of radiant energy from an incident beam by the process of cloud absorption and/or scattering. Categories Cloud Properties Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. ARM Instruments NEPHELOMETER : Nephelometer Field Campaign Instruments CEP : Cloud Extinction Probe CLDAEROSMICRO : Cloud and Aerosol Microphysical Properties EC-CONVAIR580-BULK : Environment Canada Convair 580 Bulk Parameters

309

Results of Experiments on Convective Precipitation Enhancement in the Camaguey Experimental Area, Cuba  

Science Conference Proceedings (OSTI)

Experiments on randomized seeding of individual convective clouds and cloud clusters were conducted in the Camaguey experimental area, Cuba, from 1985 through 1990 in order to elucidate whether cold-cloud dynamic seeding can be used to augment ...

Boris Koloskov; Boris Zimin; Vitaly Beliaev; Yury Seregin; Albert Chernikov; Victor Petrov; Mario Valdés; Daniel Martínez; Carlos A. Pérez; Guillermo Puente

1996-09-01T23:59:59.000Z

310

Simulating Future Changes in Arctic and Subarctic Vegetation  

Science Conference Proceedings (OSTI)

The Arctic is a sensitive system undergoing dramatic changes related to recent warming trends. Vegetation dynamics—increases in the quantity of green vegetation and a northward migration of trees into the arctic tundra—are a component of ... Keywords: Arctic, biogeography, boreal forest, climate change, forest migration, shrub encroachment, subarctic, tundra, vegetation dynamics models

Howard E. Epstein; Jed O. Kaplan; Heike Lischke; Qin Yu

2007-07-01T23:59:59.000Z

311

Cloud Interactions and Merging: Numerical Simulations  

Science Conference Proceedings (OSTI)

A total of 48 numerical experiments have been performed to study cloud interactions and merging by means of a two-dimensional multi-cell model. Two soundings of deep convection during GATE and two different magnitudes of large-scale lifting.have ...

Wei-Kuo Tao; Joanne Simpson

1984-10-01T23:59:59.000Z

312

Persistent Effects of Cloud Seeding with Silver Iodide  

Science Conference Proceedings (OSTI)

A statistical examination of precipitation records in and near areas where cloud seeding experiments have taken place in Australia strongly suggests the delayed effects of seeding. The most conspicuous effect is an increase in precipitation 1 to ...

E. K. Bigg; Enid Turton

1988-05-01T23:59:59.000Z

313

SST Sensitivities in Multiday TOGA COARE Cloud-Resolving Simulations  

Science Conference Proceedings (OSTI)

A two-dimensional cloud-resolving model (CRM) was used to simulate the evolution of convection over the western Pacific between 19 and 26 December 1992, during the Tropical Ocean Global Atmosphere Coupled Ocean–Atmosphere Response Experiment. A ...

Alexandre A. Costa; William R. Cotton; Robert L. Walko; Roger A. Pielke Sr.; Hongli Jiang

2001-02-01T23:59:59.000Z

314

On the Dynamics of Hawaiian Cloud Bands: Island Forcing  

Science Conference Proceedings (OSTI)

This study focuses on basic island scale forcing mechanisms for the formation and evolution of a band cloud typically present upwind of the island of Hawaii. By means of numerical experiments and verification of our results against observations ...

Piotr K. Smolarkiewicz; Roy M. Rasmussen; Terry L. Clark

1988-07-01T23:59:59.000Z

315

Small-Scale Variability in Warm Continental Cumulus Clouds  

Science Conference Proceedings (OSTI)

We have analyzed small-scale fluctuations in microphysical, dynamical and thermodynamical parameters measured in two warm cumulus clouds during the Cooperative Convective Precipitation Experiment (CCOPE) project (1981) in light of predictions of ...

P. H. Austin; M. B. Baker; A. M. Blyth; J. B. Jensen

1985-06-01T23:59:59.000Z

316

Tracer Study of Vertical Exchange by Cumulus Clouds  

Science Conference Proceedings (OSTI)

This paper examines the exchange of material by convective cloud processes between the mixed layer and the overlying free troposphere. It describes results of a field experiment that was conducted in Lexington, Kentucky, during the period from 20 ...

J. K. S. Ching; A. J. Alkezweeny

1986-11-01T23:59:59.000Z

317

The characterization of particle clouds using optical imaging techniques  

E-Print Network (OSTI)

Optical imaging techniques can be used to provide a better understanding of the physical properties of particle clouds. The purpose of this thesis is to design, perform and evaluate a set of experiments using optical imaging ...

Bruce, Elizabeth J. (Elizabeth Jane), 1972-

1998-01-01T23:59:59.000Z

318

95-GHz Polarimetric Radar Measurements of Orographic Cap Clouds  

Science Conference Proceedings (OSTI)

The use of millimeter-wavelength radars for cloud microphysical research was investigated in experiments at the Elk Mountain Observatory near Laramie, Wyoming, between April 1990 and March 1992. The 95-GHz polarimetric radar used in these ...

Andrew Pazmany; James Mead; Robert McIntosh; Mark Hervig; Robert Kelly; Gabor Vali

1994-02-01T23:59:59.000Z

319

Sensitivity of Surface Solar Fluxes to Cloud Parameterization  

Science Conference Proceedings (OSTI)

Experiments were performed to examine the sensitivity of computed solar fluxes using a delta-Eddington model to recent parameterizations of cloud albedo of single scattering and asymmetry factor, In particular, the changes in the surface downward ...

J. A. Ewing; R. T. Pinker

1988-03-01T23:59:59.000Z

320

Arctic Methane, Hydrates, and Global Climate  

NLE Websites -- All DOE Office Websites (Extended Search)

Arctic Methane, Hydrates, and Global Climate Arctic Methane, Hydrates, and Global Climate Speaker(s): Matthew T. Reagan Date: March 17, 2010 - 12:00pm Location: 90-3122 Paleooceanographic evidence has been used to postulate that methane may have had a significant role in regulating past climate. However, the behavior of contemporary permafrost deposits and oceanic methane hydrate deposits subjected to rapid temperature changes, like those now occurring in the arctic and those predicted under future climate change scenarios, has only recently been investigated. A recent expedition to the west coast of Spitsbergen discovered substantial methane gas plumes exiting the seafloor at depths that correspond to the upper limit of the receding gas hydrate stability zone. It has been suggested that these plumes may be the

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


321

Diurnal Cloud and Thermodynamic Variations in the Stratocumulus Transition Regime: A Case Study Using In Situ and Remote Sensors  

Science Conference Proceedings (OSTI)

Radiosonde, in situ, and surface-based remote sensor data from the Atlantic Stratocumulus Transition Experiment are used to study the diurnal cycle of cloud and thermodynamic structure. A cloud layer and decoupled subcloud layer separated by a ...

Mark A. Miller; Michael P. Jensen; Eugene E. Clothiaux

1998-07-01T23:59:59.000Z

322

Detection of Nonprecipitating Clouds with the WSR-88D: A Theoretical and Experimental Survey of Capabilities and Limitations  

Science Conference Proceedings (OSTI)

Theoretical calculations and experiments verify that the National Weather Service WSR-88D radars have the sensitivity to detect nonprecipitating clouds, but show that significant obstacles impair the generality of this cloud sensing technique. ...

Mark A. Miller; Johannes Verlinde; Craig V. Gilbert; Gregory J. Lehenbauer; Jeffrey S. Tongue; Eugene E. Clothiaux

1998-12-01T23:59:59.000Z

323

A Midlatitude Cirrus Cloud Climatology from the Facility for Atmospheric Remote Sensing. Part I: Macrophysical and Synoptic Properties  

Science Conference Proceedings (OSTI)

A uniquely extensive high cloud dataset has been collected from the University of Utah Facility for Atmospheric Remote Sensing in support of the First (ISCCP) International Satellite Cloud Climatology Project Regional Experiment extended time ...

Kenneth Sassen; James R. Campbell

2001-03-01T23:59:59.000Z

324

Physical Response of Winter Orographic Clouds over the Sierra Nevada to Airborne Seeding Using Dry Ice or Silver Iodide  

Science Conference Proceedings (OSTI)

Cloud seeding experiments devoted to physical measurements of the effects of seeding shallow stable winter orographic clouds have been conducted in the central Sierra Nevada of California from 1984 to 1986. Seeding was done by aircraft using ...

Terry Deshler; David W. Reynolds; Arlen W. Huggins

1990-04-01T23:59:59.000Z

325

Microphysical Effects of Wintertime Cloud Seeding with Silver Iodide over the Rocky Mountains. Part I: Experimental Design and Instrumentation  

Science Conference Proceedings (OSTI)

A series of winter orographic cloud seeding experiments is described in which the seeding agent and associated changes in cloud microphysics are monitored to within 300 m of the target areas (Montana and Colorado), and at the surface (Colorado ...

Arlin B. Super; Bruce A. Boe; Edmond W. Holroyd III; James A. Heimbach Jr.

1988-10-01T23:59:59.000Z

326

Cloud Computing Forensic Science Workshop  

Science Conference Proceedings (OSTI)

Cloud Computing Forensic Science Workshop. Purpose: The New Frontiers in IT and Measurement Science Rapid advances ...

2013-09-05T23:59:59.000Z

327

A marketplace for cloud resources  

Science Conference Proceedings (OSTI)

Cloud computing is an emerging paradigm aimed to offer users pay-per-use computing resources, while leaving the burden of managing the computing infrastructure to the cloud provider. We present a new programming and pricing model that gives the cloud ... Keywords: cloud computing, iaas, large-scale scheduling, pricing models, worst-case execution time

Thomas A. Henzinger; Anmol V. Singh; Vasu Singh; Thomas Wies; Damien Zufferey

2010-10-01T23:59:59.000Z

328

Cirrus Cloud Radiative and Microphysical Properties from Ground Observations and In Situ Measurements during FIRE 1991 and Their Application to Exhibit Problems in Cirrus Solar Radiative Transfer Modeling  

Science Conference Proceedings (OSTI)

Measurements from the FIRE 1991 cirrus cloud field experiment in the central United States are presented and analyzed.

S. Kinne; T. P. Ackerman; M. Shiobara; A. Uchiyama; A. J. Heymsfield; L. Miloshevich; J. Wendell; E. Eloranta; C. Purgold; R. W. Bergstrom

1997-09-01T23:59:59.000Z

329

Colliding clouds of strongly interacting spin-polarized fermions  

Science Conference Proceedings (OSTI)

Motivated by a recent experiment at MIT, we consider the collision of two clouds of spin-polarized atomic Fermi gases close to a Feshbach resonance. We explain why two dilute gas clouds, with underlying attractive interactions between their constituents, bounce off each other in the strongly interacting regime. Our hydrodynamic analysis, in excellent agreement with experiment, gives strong evidence for a metastable many-body state with effective repulsive interactions.

Taylor, Edward; Zhang Shizhong; Schneider, William; Randeria, Mohit [Department of Physics, Ohio State University, Columbus, Ohio 43210 (United States)

2011-12-15T23:59:59.000Z

330

LIRAD Observations of Tropical Cirrus Clouds in MCTEX. Part II: Optical Properties and Base Cooling in Dissipating Storm Anvil Clouds  

Science Conference Proceedings (OSTI)

During the Maritime Continent Thunderstorm Experiment (MCTEX), several decaying storm anvils were observed. The anvil clouds exhibited typical patterns of fallout and decay over a number of hours of observation. The anvil bases were initially ...

C. M. R. Platt; R. T. Austin; S. A. Young; A. J. Heymsfield

2002-11-01T23:59:59.000Z

331

Status of Wind-Diesel Applications in Arctic Climates: Preprint  

DOE Green Energy (OSTI)

The rising cost of diesel fuel and the environmental regulation for its transportation, use, and storage, combined with the clear impacts of increased arctic temperatures, is driving remote communities to examine alternative methods of providing power. Over the past few years, wind energy has been increasingly used to reduce diesel fuel consumption, providing economic, environmental, and security benefits to the energy supply of communities from Alaska to Antarctica. This summary paper describes the current state of wind-diesel systems, reviews the operation of wind-diesel plants in cold climates, discusses current research activities pertaining to these systems, and addresses their technical and commercial challenges. System architectures, dispatch strategies, and operating experience from a variety of wind-diesel systems in Alaska will be reviewed. Specific focus will also be given to the control of power systems with large amounts of wind generation and the complexities of replacing diesel engine waste heat with excess wind energy, a key factor in assessing power plants for retrofit. A brief overview of steps for assessing the viability of retrofitting diesel power systems with wind technologies will also be provided. Because of the large number of isolated diesel minigrids, the market for adding wind to these systems is substantial, specifically in arctic climates and on islands that rely on diesel-only power generation.

Baring-Gould, I.; Corbus, D.

2007-12-01T23:59:59.000Z

332

The Arctic and Subarctic Ocean Flux of Potential Vorticity and the Arctic Ocean Circulation  

Science Conference Proceedings (OSTI)

According to observations, the Arctic Ocean circulation beneath a shallow thermocline can be schematized by cyclonic rim currents along shelves and over ridges. In each deep basin, the circulation is also believed to be cyclonic. This circulation ...

Jiayan Yang

2005-12-01T23:59:59.000Z

333

CDIAC Cloud Data Sets  

NLE Websites -- All DOE Office Websites (Extended Search)

Period of Record A Gridded Climatology of Clouds over Land (1971-1996) and Ocean (1954-2008) from Surface Observations Worldwide (CDIAC NDP-026E) C.J. Hahn and S.G. Warren...

334

3. New Cloud Climatology  

NLE Websites -- All DOE Office Websites (Extended Search)

New Cloud Climatology New Cloud Climatology Computed for the summers (May-Au- gust) 2000 through 2004 (Berg and Kassianov 2008). Uses ARSCL VAP, Total Sky Imager, and radar wind profiler. * * Initial Evaluation of the Cumulus Potential Scheme at the ACRF SGP Site Larry Berg, William Gustafson, and Evgueni Kassianov Pacific Northwest National Laboratory 1. Motivation Shallow clouds are poorly predicted by current global and regional scale models. A new parameterization has been devel- oped that links the boundary-layer turbu- lence and the shallow clouds. 2. The CuP Parameterization The Cumulus Potential (CuP) param- eterization uses Probability Density Functions (PDFs) of temperature and moisture to represent the subgrid scale

335

ISCCP Cloud Data Products  

Science Conference Proceedings (OSTI)

The operational data collection phase of the International Satellite Cloud Climatology Project (ISCCP) began in July 1983. Since then, visible and infrared images from an international network of weather satellites have been routinely processed ...

William B. Rossow; Robert A. Schiffer

1991-01-01T23:59:59.000Z

336

Cloud Transmissivities for Canada  

Science Conference Proceedings (OSTI)

Transmissivities are determined for different cloud types using nine years of hourly irradiance measurements under overcast skies at six Canadian stations. Values for individual stations and for pooled data using irradiances uncorrected for ...

J. A. Davies; M. Abdel-Wahab; J. E. Howard

1985-03-01T23:59:59.000Z

337

Arctic Energy Technology Development Laboratory  

DOE Green Energy (OSTI)

The Arctic Energy Technology Development Laboratory was created by the University of Alaska Fairbanks in response to a congressionally mandated funding opportunity through the U.S. Department of Energy (DOE), specifically to encourage research partnerships between the university, the Alaskan energy industry, and the DOE. The enabling legislation permitted research in a broad variety of topics particularly of interest to Alaska, including providing more efficient and economical electrical power generation in rural villages, as well as research in coal, oil, and gas. The contract was managed as a cooperative research agreement, with active project monitoring and management from the DOE. In the eight years of this partnership, approximately 30 projects were funded and completed. These projects, which were selected using an industry panel of Alaskan energy industry engineers and managers, cover a wide range of topics, such as diesel engine efficiency, fuel cells, coal combustion, methane gas hydrates, heavy oil recovery, and water issues associated with ice road construction in the oil fields of the North Slope. Each project was managed as a separate DOE contract, and the final technical report for each completed project is included with this final report. The intent of this process was to address the energy research needs of Alaska and to develop research capability at the university. As such, the intent from the beginning of this process was to encourage development of partnerships and skills that would permit a transition to direct competitive funding opportunities managed from funding sources. This project has succeeded at both the individual project level and at the institutional development level, as many of the researchers at the university are currently submitting proposals to funding agencies, with some success.

Sukumar Bandopadhyay; Charles Chamberlin; Robert Chaney; Gang Chen; Godwin Chukwu; James Clough; Steve Colt; Anthony Covescek; Robert Crosby; Abhijit Dandekar; Paul Decker; Brandon Galloway; Rajive Ganguli; Catherine Hanks; Rich Haut; Kristie Hilton; Larry Hinzman; Gwen Holdman; Kristie Holland; Robert Hunter; Ron Johnson; Thomas Johnson; Doug Kame; Mikhail Kaneveskly; Tristan Kenny; Santanu Khataniar; Abhijeet Kulkami; Peter Lehman; Mary Beth Leigh; Jenn-Tai Liang; Michael Lilly; Chuen-Sen Lin; Paul Martin; Pete McGrail; Dan Miller; Debasmita Misra; Nagendra Nagabhushana; David Ogbe; Amanda Osborne; Antoinette Owen; Sharish Patil; Rocky Reifenstuhl; Doug Reynolds; Eric Robertson; Todd Schaef; Jack Schmid; Yuri Shur; Arion Tussing; Jack Walker; Katey Walter; Shannon Watson; Daniel White; Gregory White; Mark White; Richard Wies; Tom Williams; Dennis Witmer; Craig Wollard; Tao Zhu

2008-12-31T23:59:59.000Z

338

Development of Exhibit on Arctic Climate Change Called The Arctic: A Friend Acting Strangely Exhibition  

SciTech Connect

The exhibition, The Arctic: A Friend Acting Strangely, was developed at the Smithsonian Institution’s National Museum of Natural History (NMNH) as a part of the museum’s Forces of Change exhibit series on global change. It opened to the public in Spring 2006, in conjunction with another Forces of Change exhibit on the Earth’s atmosphere called Change Is in the Air. The exhibit was a 2000 square-foot presentation that explored the forces and consequences of the changing Arctic as documented by scientists and native residents alike. Native peoples of the Arctic have always lived with year-to-year fluctuations in weather and ice conditions. In recent decades, they have witnessed that the climate has become unpredictable, the land and sea unfamiliar. An elder in Arctic Canada recently described the weather as uggianaqtuq —an Inuit word that can suggest strange, unexpected behavior, sometimes described as that of “a friend acting strangely.” Scientists too have been documenting dramatic changes in the Arctic. Air temperatures have warmed over most—though not all—of the Arctic since the 1950s; Arctic precipitation may have increased by as much as 8%; seasonal melting of the Greenland Ice Sheet has increased on average by 16% since 1979; polar-orbiting satellites have measured a 15¬–20% decline in sea ice extent since the 1970s; aircraft reconnaissance and ship observations show a steady decrease in sea ice since the 1950s. In response to this warming, plant distributions have begun to shift and animals are changing their migration routes. Some of these changes may have beneficial effects while others may bring hardship or have costly implications. And, many scientists consider arctic change to be a ‘bell-weather’ for large-scale changes in other regions of the world. The exhibition included text, photos artifacts, hands-on interactives and other exhibitry that illustrated the changes being documented by indigenous people and scientists alike.

Stauffer, Barbara W.

2006-04-01T23:59:59.000Z

339

FORMATION OF MASSIVE MOLECULAR CLOUD CORES BY CLOUD-CLOUD COLLISION  

SciTech Connect

Recent observations of molecular clouds around rich massive star clusters including NGC 3603, Westerlund 2, and M20 revealed that the formation of massive stars could be triggered by a cloud-cloud collision. By using three-dimensional, isothermal, magnetohydrodynamics simulations with the effect of self-gravity, we demonstrate that massive, gravitationally unstable, molecular cloud cores are formed behind the strong shock waves induced by cloud-cloud collision. We find that the massive molecular cloud cores have large effective Jeans mass owing to the enhancement of the magnetic field strength by shock compression and turbulence in the compressed layer. Our results predict that massive molecular cloud cores formed by the cloud-cloud collision are filamentary and threaded by magnetic fields perpendicular to the filament.

Inoue, Tsuyoshi [Department of Physics and Mathematics, Aoyama Gakuin University, Sagamihara, Kanagawa 252-5258 (Japan); Fukui, Yasuo, E-mail: inouety@phys.aoyama.ac.jp [Department of Physics, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602 (Japan)

2013-09-10T23:59:59.000Z

340

The Arctic as a test case for an assessment of climate impacts on national security.  

SciTech Connect

The Arctic region is rapidly changing in a way that will affect the rest of the world. Parts of Alaska, western Canada, and Siberia are currently warming at twice the global rate. This warming trend is accelerating permafrost deterioration, coastal erosion, snow and ice loss, and other changes that are a direct consequence of climate change. Climatologists have long understood that changes in the Arctic would be faster and more intense than elsewhere on the planet, but the degree and speed of the changes were underestimated compared to recent observations. Policy makers have not yet had time to examine the latest evidence or appreciate the nature of the consequences. Thus, the abruptness and severity of an unfolding Arctic climate crisis has not been incorporated into long-range planning. The purpose of this report is to briefly review the physical basis for global climate change and Arctic amplification, summarize the ongoing observations, discuss the potential consequences, explain the need for an objective risk assessment, develop scenarios for future change, review existing modeling capabilities and the need for better regional models, and finally to make recommendations for Sandia's future role in preparing our leaders to deal with impacts of Arctic climate change on national security. Accurate and credible regional-scale climate models are still several years in the future, and those models are essential for estimating climate impacts around the globe. This study demonstrates how a scenario-based method may be used to give insights into climate impacts on a regional scale and possible mitigation. Because of our experience in the Arctic and widespread recognition of the Arctic's importance in the Earth climate system we chose the Arctic as a test case for an assessment of climate impacts on national security. Sandia can make a swift and significant contribution by applying modeling and simulation tools with internal collaborations as well as with outside organizations. Because changes in the Arctic environment are happening so rapidly, a successful program will be one that can adapt very quickly to new information as it becomes available, and can provide decision makers with projections on the 1-5 year time scale over which the most disruptive, high-consequence changes are likely to occur. The greatest short-term impact would be to initiate exploratory simulations to discover new emergent and robust phenomena associated with one or more of the following changing systems: Arctic hydrological cycle, sea ice extent, ocean and atmospheric circulation, permafrost deterioration, carbon mobilization, Greenland ice sheet stability, and coastal erosion. Sandia can also contribute to new technology solutions for improved observations in the Arctic, which is currently a data-sparse region. Sensitivity analyses have the potential to identify thresholds which would enable the collaborative development of 'early warning' sensor systems to seek predicted phenomena that might be precursory to major, high-consequence changes. Much of this work will require improved regional climate models and advanced computing capabilities. Socio-economic modeling tools can help define human and national security consequences. Formal uncertainty quantification must be an integral part of any results that emerge from this work.

Taylor, Mark A.; Zak, Bernard Daniel; Backus, George A.; Ivey, Mark D.; Boslough, Mark Bruce Elrick

2008-11-01T23:59:59.000Z

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


341

Snow Depth on Arctic Sea Ice  

Science Conference Proceedings (OSTI)

Snow depth and density were measured at Soviet drifting stations on multiyear Arctic sea ice. Measurements were made daily at fixed stakes at the weather station and once- or thrice-monthly at 10-m intervals on a line beginning about 500 m from ...

Stephen G. Warren; Ignatius G. Rigor; Norbert Untersteiner; Vladimir F. Radionov; Nikolay N. Bryazgin; Yevgeniy I. Aleksandrov; Roger Colony

1999-06-01T23:59:59.000Z

342

Arctic Sea Ice Albedo from AVHRR  

Science Conference Proceedings (OSTI)

The seasonal cycle of surface albedo of sea ice in the Arctic is estimated from measurements made with the Advanced Very High Resolution Radiometer (AVHRR) on the polar-orbiting satellites NOAA-10 and NOAA-11. The albedos of 145 200-km-square ...

R. W. Lindsay; D. A. Rothrock

1994-11-01T23:59:59.000Z

343

The FGGE Arctic Data Buoy Program  

Science Conference Proceedings (OSTI)

An array of about 20 drifting data buoys was established in the Arctic Ocean during the early months of 1979. The position of each buoy and the surface pressure and temperature are measured several times daily. The program expands our capability ...

A. S. Thorndike

1980-12-01T23:59:59.000Z

344

NOAAINMFS Developments Arctic Marine Research Contracts Awarded  

E-Print Network (OSTI)

on tunal porpoise, and the economic and biolog- August 1977 pacts of gas and oil exploration pre- dict the probable ecological impacts of oil and gas development on Alaska's outer continental mammals, and birds, and smaller organisms which oc- cupy the two Arctic coastal areas prior to oil and gas

345

Magellan: experiences from a Science Cloud  

E-Print Network (OSTI)

desai)@mcs.anl.gov NERSC, Lawrence Berkeley National LabComputing Facility (NERSC). In this paper, we detail theComputing Facility (NERSC). The testbed con- sists of IBM

Ramakrishnan, Lavanya

2013-01-01T23:59:59.000Z

346

Nasa's Tropical Cloud Systems and Processes Experiment  

Science Conference Proceedings (OSTI)

In July 2005, the National Aeronautics and Space Administration investigated tropical cyclogenesis, hurricane structure, and intensity change in the eastern North Pacific and western Atlantic using its ER-2 high-altitude research aircraft. The ...

J. Halverson; M. Black; R. Rogers; S. Braun; G. Heymsfield; D. Cecil; M. Goodman; R. Hood; A. Heymsfield; T. Krishnamurti; G. McFarquhar; M. J. Mahoney; J. Molinari; J. Turk; C. Velden; D-L. Zhang; E. Zipser; R. Kakar

2007-06-01T23:59:59.000Z

347

Magellan: experiences from a Science Cloud  

E-Print Network (OSTI)

at the Argonne Leadership Computing Facility (ALCF) and theArgonne Leadership Com- puting Facility (ALCF) and the National Energy Research Scientific Computing Facility (

Ramakrishnan, Lavanya

2013-01-01T23:59:59.000Z

348

Magellan: experiences from a Science Cloud  

E-Print Network (OSTI)

Leadership Computing Facility (ALCF) and the National EnergyCom- puting Facility (ALCF) and the National Energy Research

Ramakrishnan, Lavanya

2013-01-01T23:59:59.000Z

349

Magellan: experiences from a Science Cloud  

E-Print Network (OSTI)

at the Argonne Leadership Computing Facility (ALCF) and thescience at the Argonne Leadership Computing Facility and theof the Argonne Leadership Computing Facility at Argonne

Ramakrishnan, Lavanya

2013-01-01T23:59:59.000Z

350

Cirrus Clouds. Part I: A Cirrus Cloud Model  

Science Conference Proceedings (OSTI)

A two-dimensional (x, z), time-dependent, numerical cloud model is developed for the purpose of investigating the role of various physical processes involved in the maintenance of cirriform clouds. In addition to accounting for dynamic and ...

David O'C. Starr; Stephen K. Cox

1985-12-01T23:59:59.000Z

351

On the Use of Cloud Forcing to Estimate Cloud Feedback  

Science Conference Proceedings (OSTI)

Uncertainty in cloud feedback is the leading cause of discrepancy in model predictions of climate change. The use of observed or model-simulated radiative fluxes to diagnose the effect of clouds on climate sensitivity requires an accurate ...

Brian J. Soden; Anthony J. Broccoli; Richard S. Hemler

2004-10-01T23:59:59.000Z

352

Comparisons of CCN with Supercooled Clouds  

Science Conference Proceedings (OSTI)

More than 140 supercooled clouds were compared with corresponding out-of-cloud cloud condensation nuclei (CCN) measurements. In spite of significant differences in altitude, temperature, distances from cloud base, updraft velocity (W), ...

James G. Hudson; Stephen Noble; Vandana Jha

2010-09-01T23:59:59.000Z

353

Effects of CCN Concentrations on Stratus Clouds  

Science Conference Proceedings (OSTI)

Comparisons between cloud-base CCN concentrations and cloud droplet concentrations in stratus clouds over San Diego and 100 km out to sea showed a positive correlation. The supersaturation in these clouds, as derived from the matching of the CCN ...

James G. Hudson

1983-02-01T23:59:59.000Z

354

ETSI CLOUD - initial standardization requirements for cloud services  

Science Conference Proceedings (OSTI)

While the technological basis for cloud services is relatively mature, the development of the market is still at an early stage. There is considerable potential, but also a number of widely held concerns which are inhibiting mainstream adoption of cloud ... Keywords: ETSI, cloud services, standardization

Karsten Oberle; Mike Fisher

2010-08-01T23:59:59.000Z

355

More Observations of Small Funnel Clouds and Other Tubular Clouds  

Science Conference Proceedings (OSTI)

In this brief contribution, photographic documentation is provided of a variety of small, tubular-shaped clouds and of a small funnel cloud pendant from a convective cloud that appears to have been modified by flow over high-altitude mountains in ...

Howard B. Bluestein

2005-12-01T23:59:59.000Z

356

Observations of Cloud-Top Entrainment in Marine Stratocumulus Clouds  

Science Conference Proceedings (OSTI)

Measurements of the thermodynamic and dynamic properties of entrainment events in marine stratocumulus are used to explain why cloud-top entrainment instability may not lead to the breakup of the clouds and to define the role of cloud-top ...

Qing Wang; Bruce A. Albrecht

1994-06-01T23:59:59.000Z

357

The Magellan Final Report on Cloud Computing  

E-Print Network (OSTI)

resources. 1. Finding Tropical Cyclones on a Cloud Computing2010 2. Finding Tropical Cyclones on Clouds, D. Hasenkamp

Coghlan, Susan

2013-01-01T23:59:59.000Z

358

Internet ware cloud computing :Challenges  

E-Print Network (OSTI)

After decades of engineering development and infrastructural investment, Internet connections have become commodity product in many countries, and Internet scale "cloud computing" has started to compete with traditional software business through its technological advantages and economy of scale. Cloud computing is a promising enabling technology of Internet ware Cloud Computing is termed as the next big thing in the modern corporate world. Apart from the present day software and technologies, cloud computing will have a growing impact on enterprise IT and business activities in many large organizations. This paper provides an insight to cloud computing, its impacts and discusses various issues that business organizations face while implementing cloud computing. Further, it recommends various strategies that organizations need to adopt while migrating to cloud computing. The purpose of this paper is to develop an understanding of cloud computing in the modern world and its impact on organizations and businesse...

Qamar, S; Singh, Mrityunjay

2010-01-01T23:59:59.000Z

359

Mechanisms of Banner Cloud Formation  

Science Conference Proceedings (OSTI)

Banner clouds are clouds in the lee of steep mountains or sharp ridges. Their formation has previously been hypothesized as due to three different mechanisms: (i) vertical uplift in a lee vortex (which has a horizontal axis), (ii) adiabatic ...

Matthias Voigt; Volkmar Wirth

2013-11-01T23:59:59.000Z

360

Remote Sensing of Cloud Parameters  

Science Conference Proceedings (OSTI)

Day and night mapping of the global distributions of the horizontal cloud covers and the corresponding cloud-top pressure levels are derived from the same set of infrared radiance data used to retrieve clear-column temperature profiles. General ...

Moustafa T. Chahine

1982-01-01T23:59:59.000Z

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


361

A Computer for the Clouds  

NLE Websites -- All DOE Office Websites (Extended Search)

Computer for the Clouds A Computer for the Clouds August 1, 2008 By PHILIP E. ROSS Columnist IEEE Spectrum: Inside Technology In May an IBM-built supercomputer called Roadrunner...

362

Supersaturation Intermittency in Turbulent Clouds  

Science Conference Proceedings (OSTI)

It is hypothesized that bursts of high supersaturation are produced in turbulent, convective clouds through interactions between cloud droplets and the small-scale structure of atmospheric turbulence. This hypothesis is based on the observation ...

Raymond A. Shaw

2000-10-01T23:59:59.000Z

363

NIST Cloud Computing Related Publications  

Science Conference Proceedings (OSTI)

... Challenging Security Requirements for US Government Cloud Computing Adoption", December 2012 C. Dabrowski and K. Mills, "VM Leakage and ...

2013-07-31T23:59:59.000Z

364

ARM - Field Campaign - Biogenic Aerosols - Effects on Clouds and Climate:  

NLE Websites -- All DOE Office Websites (Extended Search)

govCampaignsBiogenic Aerosols - Effects on Clouds and Climate: Snowfall govCampaignsBiogenic Aerosols - Effects on Clouds and Climate: Snowfall Experiment Related Campaigns Biogenic Aerosols- Effects on Clouds and Climate 2014.02.01, Petäjä, AMF Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Biogenic Aerosols - Effects on Clouds and Climate: Snowfall Experiment 2014.02.01 - 2014.04.30 Lead Scientist : Dmitri Moisseev Description The snowfall measurement campaign, which will take place during AMF2 deployment in Finland, will focus on understanding snowfall microphysics and characterizing performance of surface based snowfall measurement instruments. This will be achieved by combining triple frequency (X, Ka, W -band) radar observations of vertical structure of the precipitation,

365

Polyethylene Pipe Failure in the Arctic - Programmaster.org  

Science Conference Proceedings (OSTI)

In the current study, a new high density polyethylene (HDPE) pipe in the Arctic region of ... Heat Tint Effects on General Corrosion Resistance of Stainless Steels .

366

Potential Oil Production from the Coastal Plain of the Arctic...  

U.S. Energy Information Administration (EIA) Indexed Site

2. Analysis Discussion Resource Assessment The USGS most recent assessment of oil and gas resources of ANWR Coastal Plain (The Oil and Gas Resource Potential of the Arctic...

367

Potential Oil Production from the Coastal Plain of the Arctic...  

U.S. Energy Information Administration (EIA) Indexed Site

Potential Oil Production from the Coastal Plain of the Arctic National Wildlife Refuge: Updated Assessment Glossary ANILCA: Alaska National Interest Lands Conservation Act ANS:...

368

Contract RBAC in cloud computing  

Science Conference Proceedings (OSTI)

Cloud computing is a fast growing field, which is arguably a new computing paradigm. In cloud computing, computing resources are provided as services over the Internet and users can access resources based on their payments. The issue of access control ... Keywords: Cloud computing, Contract, Contract RBAC, Datacenter, RBAC

Hsing-Chung (Jack) Chen, Marsha Anjanette Violetta, Cheng-Ying Yang

2013-11-01T23:59:59.000Z

369

Improving Utilization of Infrastructure Clouds  

Science Conference Proceedings (OSTI)

A key advantage of infrastructure-as-a-service (IaaS) clouds is providing users on-demand access to resources. To provide on-demand access, however, cloud providers must either significantly overprovision their infrastructure (and pay a high price for ... Keywords: Cloud Computing, Infrastructure-as-a-Service, High Throughput Computing

Paul Marshall; Kate Keahey; Tim Freeman

2011-05-01T23:59:59.000Z

370

Parameterizing Vertically Coherent Cloud Distributions  

Science Conference Proceedings (OSTI)

A parameterization for specifying subgrid-scale cloud distributions in atmospheric models is developed. The fractional area of a grid-scale column in which clouds from two levels overlap (i.e., the cloud overlap probability) is described in terms ...

John W. Bergman; Philip J. Rasch

2002-07-01T23:59:59.000Z

371

Physical Interpretation of Results from the HIPLEX-1 Experiment  

Science Conference Proceedings (OSTI)

The general characteristics of the clouds that were included in the HIPLEX-1 experiment are reviewed, and the results for the response variables are interpreted in light of other measurements from the instrumented aircraft. In most seeded clouds, ...

William A. Cooper; R. Paul Lawson

1984-04-01T23:59:59.000Z

372

Climate-derived tensions in Arctic security.  

Science Conference Proceedings (OSTI)

Globally, there is no lack of security threats. Many of them demand priority engagement and there can never be adequate resources to address all threats. In this context, climate is just another aspect of global security and the Arctic just another region. In light of physical and budgetary constraints, new security needs must be integrated and prioritized with existing ones. This discussion approaches the security impacts of climate from that perspective, starting with the broad security picture and establishing how climate may affect it. This method provides a different view from one that starts with climate and projects it, in isolation, as the source of a hypothetical security burden. That said, the Arctic does appear to present high-priority security challenges. Uncertainty in the timing of an ice-free Arctic affects how quickly it will become a security priority. Uncertainty in the emergent extreme and variable weather conditions will determine the difficulty (cost) of maintaining adequate security (order) in the area. The resolution of sovereignty boundaries affects the ability to enforce security measures, and the U.S. will most probably need a military presence to back-up negotiated sovereignty agreements. Without additional global warming, technology already allows the Arctic to become a strategic link in the global supply chain, possibly with northern Russia as its main hub. Additionally, the multinational corporations reaping the economic bounty may affect security tensions more than nation-states themselves. Countries will depend ever more heavily on the global supply chains. China has particular needs to protect its trade flows. In matters of security, nation-state and multinational-corporate interests will become heavily intertwined.

Backus, George A.; Strickland, James Hassler

2008-09-01T23:59:59.000Z

373

Spatial and Temporal Variability of Aerosol Particles in Arctic Spring  

SciTech Connect

The objective of this work is to investigate the variability in the particle number concentration that may affect climate change assessment for Arctic regions. The Indirect and Semi-Direct Aerosol Campaign (ISDAC) was conducted in April 2008, in the vicinities of Fairbanks and Barrow, Alaska. Measurements of particle number concentrations and size distributions were conducted using a Passive Cavity Aerosol Spectrometer Probe (PCASP-100X) mounted under the Convair-580 aircraft wing. Total number concentration of particles (Na) with diameters in the range 0.12-3 ?m was determined for polluted and clean air masses during times when the air was free of clouds and/or precipitation. Variability in Na was considered for both vertical profiles and constant altitude (horizontal) flight legs. This variability can have important implications for estimates of particle properties used in global climate model (GCM) simulations. When aerosol particle layers were encountered, Na rapidly increased from 25 cm-3 up to 550 cm-3 within relatively clean air masses, and reached up to 2200 cm-3 within polluted air masses, dominated by biomass burning pollution. When averaging Na over different distance scales, it was found that Na=140 cm-3 represent an average value for the majority of the encountered clean cases; while Na=720 cm-3 is a mean for polluted cases dominated by biomass burning plumes. These estimates, however, would not capture the details of particle layers encountered during most of the flights. Average aerosol particle characteristics can be difficult to interpret, especially during polluted cases, due to small-scale spatial and temporal variability.

Shantz, Nicole C.; Gultepe, Ismail; Liu, Peter; Earle, Michael; Zelenyuk, Alla

2012-10-01T23:59:59.000Z

374

A Smooth Cloud Model  

Science Conference Proceedings (OSTI)

In this paper a large-eddy “smooth” cloud (SC) model will be presented with smooth implying that the entire model converges under a Newton-based solution procedure or that time scales within the SC model are being resolved. Besides ensuring that ...

J. M. Reisner; C. A. Jeffery

2009-06-01T23:59:59.000Z

375

Results of On-Top Glaciogenic Cloud Seeding in Thailand. Part II: Exploratory Analyses  

Science Conference Proceedings (OSTI)

Randomized, cold-cloud, rain-enhancement experiments were carried out during 1991–98 in the Bhumibol catchment area in northwestern Thailand. Exploratory experimentation in 1991 and 1993 was followed by a demonstration experiment, limited to A-...

William L. Woodley; Daniel Rosenfeld; Bernard A. Silverman

2003-07-01T23:59:59.000Z

376

Cumulus Cloud Properties Derived Using Landsat Satellite Data  

Science Conference Proceedings (OSTI)

Landsat Multispectral Scanner (MSS) digital data are used to remotely sense cumulus cloud properties such as cloud fraction and cloud reflectance, along with the distribution of cloud number and cloud fraction as a function of cloud size. The ...

Bruce A. Wielicki; Ronald M. Welch

1986-03-01T23:59:59.000Z

377

The Magellan Final Report on Cloud Computing  

Science Conference Proceedings (OSTI)

The goal of Magellan, a project funded through the U.S. Department of Energy (DOE) Office of Advanced Scientific Computing Research (ASCR), was to investigate the potential role of cloud computing in addressing the computing needs for the DOE Office of Science (SC), particularly related to serving the needs of mid- range computing and future data-intensive computing workloads. A set of research questions was formed to probe various aspects of cloud computing from performance, usability, and cost. To address these questions, a distributed testbed infrastructure was deployed at the Argonne Leadership Computing Facility (ALCF) and the National Energy Research Scientific Computing Center (NERSC). The testbed was designed to be flexible and capable enough to explore a variety of computing models and hardware design points in order to understand the impact for various scientific applications. During the project, the testbed also served as a valuable resource to application scientists. Applications from a diverse set of projects such as MG-RAST (a metagenomics analysis server), the Joint Genome Institute, the STAR experiment at the Relativistic Heavy Ion Collider, and the Laser Interferometer Gravitational Wave Observatory (LIGO), were used by the Magellan project for benchmarking within the cloud, but the project teams were also able to accomplish important production science utilizing the Magellan cloud resources.

,; Coghlan, Susan; Yelick, Katherine

2011-12-21T23:59:59.000Z

378

Session Papers North Slope of Alaska and Adjacent Arctic Ocean...  

NLE Websites -- All DOE Office Websites (Extended Search)

over the NSAAAO throughout the year, it is well positioned to address these issues. Ice Phase Clouds Ice phase clouds are important globally, not just regionally. However, at...

379

The Effect of the Arbitrary Level Assignment of Satellite Cloud Motion Wind Vectors on Wind Analyses in the Pre-thunderstorm Environment  

Science Conference Proceedings (OSTI)

The impact of satellite-derived cloud motion vectors (CMVs) on analysts of winds measured by rawinsondes during the 1979 SESAME Experiment is studied in two case studies (10 April and 9 May 1979). Cloud motion vectors are both arbitrarily ...

Cynthia A. Peslen; Steven E. Koch; Louis W. Uccellini

1986-05-01T23:59:59.000Z

380

Mechanisms of Low Cloud–Climate Feedback in Idealized Single-Column Simulations with the Community Atmospheric Model, Version 3 (CAM3)  

Science Conference Proceedings (OSTI)

This study investigates the physical mechanism of low cloud feedback in the Community Atmospheric Model, version 3 (CAM3) through idealized single-column model (SCM) experiments over the subtropical eastern oceans. Negative cloud feedback is ...

Minghua Zhang; Christopher Bretherton

2008-09-01T23:59:59.000Z

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


381

Long-Term Behavior of Cloud Systems in TOGA COARE and Their Interactions with Radiative and Surface Processes. Part I: Two-Dimensional Modeling Study  

Science Conference Proceedings (OSTI)

Two-dimensional cloud-resolving modeling of tropical cloud systems was performed for a 39-day period (5 December 1992 through 12 January 1993) during the Tropical Ocean Global Atmosphere (TOGA) Coupled Ocean–Atmosphere Response Experiment (COARE)...

Xiaoqing Wu; Wojciech W. Grabowski; Mitchell W. Moncrieff

1998-09-01T23:59:59.000Z

382

High performance computing network for cloud environment using simulators  

E-Print Network (OSTI)

Cloud computing is the next generation computing. Adopting the cloud computing is like signing up new form of a website. The GUI which controls the cloud computing make is directly control the hardware resource and your application. The difficulty part in cloud computing is to deploy in real environment. Its' difficult to know the exact cost and it's requirement until and unless we buy the service not only that whether it will support the existing application which is available on traditional data center or had to design a new application for the cloud computing environment. The security issue, latency, fault tolerance are some parameter which we need to keen care before deploying, all this we only know after deploying but by using simulation we can do the experiment before deploying it to real environment. By simulation we can understand the real environment of cloud computing and then after it successful result we can start deploying your application in cloud computing environment. By using the simulator it...

Singh, N Ajith

2012-01-01T23:59:59.000Z

383

Arctic Sea Ice Decline: Observations, Projections, Mechanisms, and Implications  

E-Print Network (OSTI)

or phase space. In this work we con- sider the trajectory of sea ice in the ice thickness phase space. We175 Arctic Sea Ice Decline: Observations, Projections, Mechanisms, and Implications Geophysical Is the Trajectory of Arctic Sea Ice? Harry L. Stern and Ronald W. Lindsay Polar Science Center, Applied Physics

Lindsay, Ron

384

Near-Inertial Wave Propagation in the Western Arctic  

Science Conference Proceedings (OSTI)

From October 1997 through October 1998, the Surface Heat Budget of the Arctic (SHEBA) ice camp drifted across the western Arctic Ocean, from the central Canada Basin over the Northwind Ridge and across the Chukchi Cap. During much of this period, ...

Robert Pinkel

2005-05-01T23:59:59.000Z

385

Semantic-based web service discovery and chaining for building an Arctic spatial data infrastructure  

Science Conference Proceedings (OSTI)

Increasing interests in a global environment and climate change have led to studies focused on the changes in the multinational Arctic region. To facilitate Arctic research, a spatial data infrastructure (SDI), where Arctic data, information, and services ... Keywords: Arctic, Crawler, Hydrology, Knowledge base, Ontology, SDI, Semantic, Service chain

W. Li; C. Yang; D. Nebert; R. Raskin; P. Houser; H. Wu; Z. Li

2011-11-01T23:59:59.000Z

386

The evolution of interstellar clouds in a streaming hot plasma including heat conduction  

E-Print Network (OSTI)

To examine the evolution of giant molecular clouds in the stream of a hot plasma we performed two-dimensional hydrodynamical simulations that take full account of self-gravity, heating and cooling effects and heat conduction by electrons. We use the thermal conductivity of a fully ionized hydrogen plasma proposed by Spitzer and a saturated heat flux according to Cowie & McKee in regions where the mean free path of the electrons is large compared to the temperature scaleheight. Significant structural and evolutionary differences occur between simulations with and without heat conduction. Dense clouds in pure dynamical models experience dynamical destruction by Kelvin-Helmholtz (KH) instability. In static models heat conduction leads to evaporation of such clouds. Heat conduction acting on clouds in a gas stream smooths out steep temperature and density gradients at the edge of the cloud because the conduction timescale is shorter than the cooling timescale. This diminishes the velocity gradient between the streaming plasma and the cloud, so that the timescale for the onset of KH instabilities increases, and the surface of the cloud becomes less susceptible to KH instabilities. The stabilisation effect of heat conduction against KH instability is more pronounced for smaller and less massive clouds. As in the static case more realistic cloud conditions allow heat conduction to transfer hot material onto the cloud's surface and to mix the accreted gas deeper into the cloud.

W. Vieser; G. Hensler

2007-04-26T23:59:59.000Z

387

Statistical cloud coverage as a function of cloud optical thickness  

Science Conference Proceedings (OSTI)

The time-averaged, daylight fractional statistical cloud coverages as a function of cloud optical thickness and selected values of cloud transmission were determined for various geographic areas using D1 data from the International Satellite Cloud Climatology Project (ISCCP). The regions of interest chosen for this report are: global earth, global sea, global land, global coast, and the six 30{degree}-latitude bands over sea, over land, and over coast with longitude 0{degree}--360{degree}. This statistical information is deduced from data determined from satellite measurements of terrestrial, atmospheric and cloud properties by the International Satellite Cloud Climatology Project. In particular the results are based on the ISCCP D1 data base.

Brower, K.L.

1998-07-01T23:59:59.000Z

388

Hupmobile cloud chamber parameters  

SciTech Connect

The accompanying table lists the presently selected parameters for the twelve cloud chambers. The chambers are numbered consecutively from 4 through 15 as they are lined up in the bunker. The lowest number is closest to the source. All except the first chamber have some thin metal filters to attenuate the flux and harden the spectrum. Cloud chambers 10, 12, and 14 are shielded by a collimator with about 200 pinholes in it. The flux in these chambers is attenuated by the ratio of the pinhole area to total beam area which is a factor of 50. Various gases and gas pressures are used to obtain suitable track lengths and interaction cross sections. Neon, argon, and krypton are used to obtain photo electrons. Hydrogen is used to obtain Compton electrons.

Hansen, N. E.

1967-09-28T23:59:59.000Z

389

An Automated Cirrus Cloud Detection Method for a Ground-Based Cloud Image  

Science Conference Proceedings (OSTI)

Cloud detection is a basic research for achieving cloud-cover state and other cloud characteristics. Because of the influence of sunlight, the brightness of sky background on the ground-based cloud image is usually nonuniform, which increases the ...

Jun Yang; Weitao Lu; Ying Ma; Wen Yao

2012-04-01T23:59:59.000Z

390

A Cloud-Resolving Model with an Adaptive Vertical Grid for Boundary Layer Clouds  

Science Conference Proceedings (OSTI)

Accurate cloud-resolving model simulations of cloud cover and cloud water content for boundary layer clouds are difficult to achieve without vertical grid spacing well below 100 m, especially for inversion-topped stratocumulus. The need for fine ...

Roger Marchand; Thomas Ackerman

2011-05-01T23:59:59.000Z

391

ARM - Field Campaign - Cloud LAnd Surface Interaction Campaign (CLASIC)  

NLE Websites -- All DOE Office Websites (Extended Search)

govCampaignsCloud LAnd Surface Interaction Campaign (CLASIC) govCampaignsCloud LAnd Surface Interaction Campaign (CLASIC) Campaign Links CLASIC Website Related Campaigns CLASIC - SAM Support 2007.06.09, DeVore, SGP CLASIC - 9.4 GHz Phase Array Radar 2007.06.08, Kollias, SGP CLASIC - Southern Great Plains Aerosol Evolution Study (SGPAES) 2007.06.08, Collins, SGP CLASIC - Land Surface 2007.06.01, Jackson, SGP CLASIC - Radiosonde Campaign 2007.06.01, Orr, SGP CLASIC - SGP Particle Phase Experiment 2007.06.01, Martin, SGP CLASIC - Land-Cloud Coupled Data Assimilation System 2007.06.01, Jackson, SGP Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Cloud LAnd Surface Interaction Campaign (CLASIC) 2007.06.01 - 2007.06.30 Website : http://acrf-campaign.arm.gov/clasic/ Lead Scientist : Mark Miller

392

Preliminary definition of Barstow standard cloud model  

DOE Green Energy (OSTI)

The motion of cloud shadows across a collector field for a central receiver solar power plant can affect the design of such a facility. Cloud models were developed to be used for basis of design in technology areas. The first effect, that of the temperature gradient, is simulated by postulating the worst case cloud situation. The cyclic effects require realistic cloud shadow time histories for simulation. Cloud shadow models were developed to determine probable cloud type, the cloud area and shape, cloud velocity and cloud-to-cloud spacing. The probability of cloud occurrence is estimated. A collector field computer program is run to determine the effect of cloud variables on collector field power delivery capability. Recommendation of cloud models to be used for basis of design are then made.

None

1978-04-05T23:59:59.000Z

393

CloudCast: Cloud Computing for Short-Term Weather Forecasts  

Science Conference Proceedings (OSTI)

CloudCast provides clients with personalized short-term weather forecasts based on their current location using cloud services

Dilip Kumar Krishnappa; David Irwin; Eric Lyons; Michael Zink

2013-01-01T23:59:59.000Z

394

Cumulus Clouds and Reflected Sunlight  

NLE Websites -- All DOE Office Websites (Extended Search)

Cumulus Clouds and Reflected Sunlight Cumulus Clouds and Reflected Sunlight from Landsat ETM+ G. Wen and L. Oreopoulos National Aeronautics and Space Administration Goddard Space Flight Center University of Maryland Baltimore County Joint Center of Earth System Technology Greenbelt, Maryland R. F. Cahalan and S. C. Tsay National Aeronautics and Space Administration Goddard Space Flight Center Greenbelt, Maryland Introduction Cumulus clouds attenuate solar radiation casting shows on the ground. Cumulus clouds can also enhance solar radiation in the clear region nearby. The enhancement of down-welling solar radiation has been observed at the ground level in the clear region near cumulus clouds (Mims and Frederick 1994). The additional diffuse radiation source from cumulus clouds makes the clear gaps appear to be

395

Size of Cloud from Shadow  

NLE Websites -- All DOE Office Websites (Extended Search)

Size of Cloud from Shadow Size of Cloud from Shadow Name: mike Status: other Grade: other Location: N/A Country: USA Date: Summer 2011 Question: I see a cloud and I see its shadow in a field - knowing high sun angles - is there a way of telling how far away the cloud is or how big? - I am thinking if the shadow is 30' wide and the sun is at 2:00 pm- ? Replies: Hi Mike, Try this, draw a small circle representing the Sun. Somewhere below this circle and maybe to the right, draw an oblong, make this oblong bigger than the circle. Now connect the leftmost edge of the circle with the leftmost edge of the oblong with a straight line. Do the same for the rightmost edges. The oblong now represent the shadow of a cloud on the ground, and the lines represent the rays of the sun passing along the edges of the cloud.

396

ARM - Measurement - Total cloud water  

NLE Websites -- All DOE Office Websites (Extended Search)

cloud water cloud water ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Total cloud water The total concentration (mass/vol) of ice and liquid water particles in a cloud; this includes condensed water content (CWC). Categories Cloud Properties Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. External Instruments NCEPGFS : National Centers for Environment Prediction Global Forecast System Field Campaign Instruments CSI : Cloud Spectrometer and Impactor PDI : Phase Doppler Interferometer

397

ARM - Measurement - Cloud droplet size  

NLE Websites -- All DOE Office Websites (Extended Search)

droplet size droplet size ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Cloud droplet size Linear size (e.g. radius or diameter) of a cloud particle Categories Cloud Properties Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. Field Campaign Instruments CPI : Cloud Particle Imager CVI-AIR : Counterflow Virtual Impactor MIRAI : JAMSTEC Research Vessel Mirai PDI : Phase Doppler Interferometer UAV-PROTEUS-MICRO : Proteus Cloud Microphysics Instruments SPEC-CPI : Stratton Park Engineering Company - Cloud particle imager

398

Cyclotron Resonances in Electron Cloud Dynamics  

Science Conference Proceedings (OSTI)

A new set of resonances for electron cloud dynamics in the presence of a magnetic field has been found. For short beam bunch lengths and low magnetic fields where lbstripes" found for non-resonant cases. Simulations with the 2D computer code POSINST, as well as a single-particle tracking code, were used to elucidate the physics of the dynamics. The existence of the resonances has been confirmed in experiments at PEP-II. The resonances are expected to affect the electron cloud dynamics in the fringe fields of conventional lattice magnets and in wigglers, where the magnetic fields are low. Results of the simulations and experimental observations, the reason for the bunch-length dependence, and details of the dynamics are discussed here.

Celata, C. M.; Furman, Miguel A.; Vay, J.-L.; Ng, J. S.T.; Grote, D. P.; Pivi, M. T. F.; Wang, L. F.

2009-04-29T23:59:59.000Z

399

Broken and inhomogeneous cloud impact on satellite cloud particle effective radius and cloudphase retrievals  

E-Print Network (OSTI)

on the particle size distribution, height, and thermo- dynamic phase of clouds. Water and ice clouds have parameterizations is the global dis- tribution of cloud thermodynamic phase, i.e., whether a cloud is composed on satellitederived cloud particle effective radius (re) and cloud phase (CPH) for broken and overcast inhomogeneous

Stoffelen, Ad

400

DOE/SC-ARM-P-07-006 Evaluation of Mixed-Phase Cloud Microphysics  

NLE Websites -- All DOE Office Websites (Extended Search)

6 6 Evaluation of Mixed-Phase Cloud Microphysics Parameterizations with the NCAR Single Column Climate Model (SCAM) and ARM Observations Second Quarter 2007 ARM Metric Report April 2007 Xiaohong Liu and Steven J. Ghan Pacific Northwest National Laboratory Richland, Washington Shaocheng Xie Lawrence Livermore National Laboratory Livermore, California Work supported by the U.S. Department of Energy, Office of Science, Office of Biological and Environmental Research X. Lui, S.J. Ghan, and S. Xie, DOE/SC-ARM/P-07-006 Summary Mixed-phase stratus clouds are ubiquitous in the Arctic and play an important role in climate in this region. However, climate models have generally proven unsuccessful at simulating the partitioning of condensed water

Note: This page contains sample records for the topic "arctic cloud experiment" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
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401

TC_CLOUD_REGIME.cdr  

NLE Websites -- All DOE Office Websites (Extended Search)

Tropical cloud properties as a function of regime Regimes? Monsoon versus Break * Different synoptic vertical velocity profiles - Changes convective inhibition, corresponding...

402

Service Availability in Cloud Computing.  

E-Print Network (OSTI)

?? Cloud computing provides access to on-demand computing resources and storage space, whereby applications and data are hosted with data centers managed by third parties,… (more)

Adegoke, Adekunle

2013-01-01T23:59:59.000Z

403

China Total Cloud Amount Trends  

NLE Websites -- All DOE Office Websites (Extended Search)

Trends in Total Cloud Amount Over China DOI: 10.3334CDIACcli.008 data Data image Graphics Investigator Dale P. Kaiser Carbon Dioxide Information Analysis Center, Environmental...

404

Posters Ship-Based Measurements of Cloud Optical Properties  

NLE Websites -- All DOE Office Websites (Extended Search)

7 7 Posters Ship-Based Measurements of Cloud Optical Properties During the Atlantic Stratocumulus Transition Experiment A. B. White Cooperative Institute for Research in Environmental Sciences University of Colorado at Boulder National Oceanic and Atmospheric Administration Boulder, Colorado C. W. Fairall National Oceanic and Atmospheric Administration Environmental Research Laboratories Environmental Technology Laboratory Boulder, Colorado Introduction The Atlantic Stratocumulus Transition Experiment (ASTEX), conducted in June 1992, was designed with the broad goal of improving the dynamical, radiative, and microphysical models of marine boundary layer (MBL) clouds. This goal was pursued by combining measurements from a number of different platforms including aircraft,

405

The Monterey Area Ship Track Experiment  

Science Conference Proceedings (OSTI)

In June 1994 the Monterey Area Ship Track (MAST) experiment was conducted off the coast of California to investigate the processes behind anthropogenic modification of cloud albedo. The motivation for the MAST experiment is described here, as ...

Philip A. Durkee; Kevin J. Noone; Robert T. Bluth

2000-08-01T23:59:59.000Z

406

Characteristics of CALIPSO and CloudSat Backscatter at the Top Center Layers of Mesoscale Convective Systems and Relation to Cloud Microphysics  

Science Conference Proceedings (OSTI)

Following the discovery of anomalously high values of lidar integrated attenuated backscatter near the top center layers of mesoscale convective systems (MCSs) observed by the NASA Lidar In-Space Technology Experiment (LITE), a search of Cloud ...

C. M. R. Platt; M. A. Vaughan; R. T. Austin

2011-02-01T23:59:59.000Z

407

Cloud Microphysical Relationships in California Marine Stratus  

Science Conference Proceedings (OSTI)

Cloud microphysical measurements off the southern California coast are presented and compared with in situ airborne measurements of cloud condensation nuclei (CCN) spectra. Large-scale variations in cloud droplet concentrations were due to CCN ...

James G. Hudson; Gunilla Svensson

1995-12-01T23:59:59.000Z

408

Statistical Description of Radiation Transfer in Clouds  

Science Conference Proceedings (OSTI)

The statistical characteristics of simulated cloud fields constructed based on Poisson point fluxes are studied. The input parameters of mathematical models of cloudiness include the cloud fraction and the mean horizontal size of clouds ...

Georgi A. Titov

1990-01-01T23:59:59.000Z

409

Radiative Effects of Cloud-Type Variations  

Science Conference Proceedings (OSTI)

Radiative flux changes induced by the occurrence of different cloud types are investigated using International Satellite Cloud Climatology Project cloud data and a refined radiative transfer model from National Aeronautics and Space ...

Ting Chen; William B. Rossow; Yuanchong Zhang

2000-01-01T23:59:59.000Z

410

CALIPSO/CALIOP Cloud Phase Discrimination Algorithm  

Science Conference Proceedings (OSTI)

The current cloud thermodynamic phase discrimination by Cloud-Aerosol Lidar Pathfinder Satellite Observations (CALIPSO) is based on the depolarization of backscattered light measured by its lidar [Cloud-Aerosol Lidar with Orthogonal Polarization (...

Yongxiang Hu; David Winker; Mark Vaughan; Bing Lin; Ali Omar; Charles Trepte; David Flittner; Ping Yang; Shaima L. Nasiri; Bryan Baum; Robert Holz; Wenbo Sun; Zhaoyan Liu; Zhien Wang; Stuart Young; Knut Stamnes; Jianping Huang; Ralph Kuehn

2009-11-01T23:59:59.000Z

411

The Visualization of Cloud Droplet Spectra  

Science Conference Proceedings (OSTI)

This paper draws attention to the use of readily available, wire cage graphics for inspecting cloud droplet spectra measured using a Forward Light-Scattering Spectrometer Probe. The high resolution cloud droplet spectra from two different clouds ...

Robert R. Czys

1989-02-01T23:59:59.000Z

412

A Survey on Cloud Provider Security  

E-Print Network (OSTI)

A Survey on Cloud Provider Security Measures Alex Pucher, Stratos Dimopoulos Abstract Cloud take advantage of this model already, but security and privacy concerns limit the further adoption agencies and start offering security certifications and separate tightly controlled "government" cloud

413

Artificial Cloud Seeding Using Liquid Carbon Dioxide: Comparisons of Experimental Data and Numerical Analyses  

Science Conference Proceedings (OSTI)

An artificial seeding experiment was carried out over the Genkai Sea, Japan, using liquid carbon dioxide. The seeded cloud was followed by an aircraft and radar at Kyushu University. A radar-echo intensity of 19 dBZ was formed in the seeded cloud ...

Jinichiro Seto; Kikuro Tomine; Kenji Wakimizu; Koji Nishiyama

2011-07-01T23:59:59.000Z

414

Evaluating I/O aware network management for scientific workflows on networked clouds  

Science Conference Proceedings (OSTI)

This paper presents a performance evaluation of scientific workflows on networked cloud systems with particular emphasis on evaluating the effect of provisioned network bandwidth on application I/O performance. The experiments were run on ExoGENI, a ... Keywords: I/O performance, networked clouds, performance evaluation, performance monitoring, scientific workflows

Anirban Mandal, Paul Ruth, Ilya Baldin, Yufeng Xin, Claris Castillo, Mats Rynge, Ewa Deelman

2013-11-01T23:59:59.000Z

415

Simulating mixed-phase Arctic stratus clouds: Sensitivity to ice initiation mechanisms  

E-Print Network (OSTI)

parameterization in BRM scheme accounts for two general mech- anisms distinguishable according to the involvement of liquid phase in the ice

Sednev, I.

2009-01-01T23:59:59.000Z

416

Simulation of Arctic Clouds in Climate Models | U.S. DOE Office...  

NLE Websites -- All DOE Office Websites (Extended Search)

News In the News In Focus Presentations & Testimony Recovery Act About Organization Budget Field Offices Federal Advisory Committees History Scientific and Technical...

417

Study of Mechanisms of Aerosol Indirect Effects on Glaciated Clouds: Progress during the Project Final Technical Report  

SciTech Connect

This 3-year project has studied how aerosol pollution influences glaciated clouds. The tool applied has been an 'aerosol-cloud model'. It is a type of Cloud-System Resolving Model (CSRM) modified to include 2-moment bulk microphysics and 7 aerosol species, as described by Phillips et al. (2009, 2013). The study has been done by, first, improving the model and then performing sensitivity studies with validated simulations of a couple of observed cases from ARM. These are namely the Tropical Warm Pool International Cloud Experiment (TWP-ICE) over the tropical west Pacific and the Cloud and Land Surface Interaction Campaign (CLASIC) over Oklahoma. During the project, sensitivity tests with the model showed that in continental clouds, extra liquid aerosols (soluble aerosol material) from pollution inhibited warm rain processes for precipitation production. This promoted homogeneous freezing of cloud droplets and aerosols. Mass and number concentrations of cloud-ice particles were boosted. The mean sizes of cloud-ice particles were reduced by the pollution. Hence, the lifetime of glaciated clouds, especially ice-only clouds, was augmented due to inhibition of sedimentation and ice-ice aggregation. Latent heat released from extra homogeneous freezing invigorated convective updrafts, and raised their maximum cloud-tops, when aerosol pollution was included. In the particular cases simulated in the project, the aerosol indirect effect of glaciated clouds was twice than of (warm) water clouds. This was because glaciated clouds are higher in the troposphere than water clouds and have the first interaction with incoming solar radiation. Ice-only clouds caused solar cooling by becoming more extensive as a result of aerosol pollution. This 'lifetime indirect effect' of ice-only clouds was due to higher numbers of homogeneously nucleated ice crystals causing a reduction in their mean size, slowing the ice-crystal process of snow production and slowing sedimentation. In addition to the known indirect effects (glaciation, riming and thermodynamic), new indirect effects were discovered and quantified due to responses of sedimentation, aggregation and coalescence in glaciated clouds to changing aerosol conditions. In summary, the change in horizontal extent of the glaciated clouds ('lifetime indirect effects'), especially of ice-only clouds, was seen to be of higher importance in regulating aerosol indirect effects than changes in cloud properties ('cloud albedo indirect effects').

Phillips, Vaughan T. J.

2013-10-18T23:59:59.000Z

418

NIST Joint Cloud and Big Data Workshop  

Science Conference Proceedings (OSTI)

NIST Joint Cloud and Big Data Workshop. Purpose: ... The second and third days of the workshop focused on the intersection of Cloud and Big Data. ...

2013-01-31T23:59:59.000Z

419

6.1 Cloud Management Broker  

Science Conference Proceedings (OSTI)

... the cloud-management-broker programming or human interface, and ... broker notifies cloud-user with error specifics or ... Transient errors can be retried ...

2010-11-02T23:59:59.000Z

420

Radiative Effects of Cloud Inhomogeneity and  

NLE Websites -- All DOE Office Websites (Extended Search)

cloud-overlap assumptions and optical property approximations (Del Genio et al. 1996; Fowler and Randall 1996; Liang and Wang 1997). While GCMs require convection and cloud...

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


421

Cloud Computing Towards Technological Convergence  

Science Conference Proceedings (OSTI)

With the popularization and improvement of social and industrial IT development, information appears to explosively increase, and people put much higher expectations on the services of computing, communication and network. Today's public communication ... Keywords: Architectural Strategies, Cloud Computing, Cloud Environments, Communication Network, Computing, Convergence

P. Sasikala

2011-10-01T23:59:59.000Z

422

Enabling cloud interoperability with COMPSs  

Science Conference Proceedings (OSTI)

The advent of Cloud computing has given to researchers the ability to access resources that satisfy their growing needs, which could not be satisfied by traditional computing resources such as PCs and locally managed clusters. On the other side, such ... Keywords: PaaS, cloud computing, data mining, parallel programming models

Fabrizio Marozzo; Francesc Lordan; Roger Rafanell; Daniele Lezzi; Domenico Talia; Rosa M. Badia

2012-08-01T23:59:59.000Z

423

ARM - Measurement - Cloud base height  

NLE Websites -- All DOE Office Websites (Extended Search)

base height base height ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Cloud base height For a given cloud or cloud layer, the lowest level of the atmosphere where cloud properties are detectable. Categories Cloud Properties Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. ARM Instruments BLC : Belfort Laser Ceilometer MPL : Micropulse Lidar MWRP : Microwave Radiometer Profiler RL : Raman Lidar VCEIL : Vaisala Ceilometer External Instruments NOAASURF : NOAA Surface Meteorology Data, collected by NWS and NCDC

424

ARM - Measurement - Cloud ice particle  

NLE Websites -- All DOE Office Websites (Extended Search)

ice particle ice particle ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Cloud ice particle Particles made of ice found in clouds. Categories Cloud Properties Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. ARM Instruments MET : Surface Meteorological Instrumentation Field Campaign Instruments REPLICATOR : Balloon-borne Ice Crystal Replicator CPI : Cloud Particle Imager CVI-AIR : Counterflow Virtual Impactor LEARJET : Lear Jet PARTIMG : Particle imager UAV-PROTEUS-MICRO : Proteus Cloud Microphysics Instruments

425

TWP Island Cloud Trail Studies  

NLE Websites -- All DOE Office Websites (Extended Search)

Pacific Island Cloud Trail Studies Pacific Island Cloud Trail Studies W. M. Porch Los Alamos National Laboratory Los Alamos, New Mexico S. Winiecki University of Chicago Chicago, Illinois Introduction Images and surface temperature measurements from the U.S. Department of Energy (DOE) Multi- spectral Thermal Imaging (MTI) satellite are combined with geostationary meteorological satellite (GMS) images during 2000 and 2001 to better understand cloud trail formation characteristics from the Atmospheric Radiation Measurement (ARM) Tropical Western Pacific (TWP) site. Figure 1 shows a comparison on two consecutive days in December 2000. The day for which a cloud trail developed was more moist and cooler at the altitude the cloud developed (about 600 m) and there was very little

426

ARM - Measurement - Cloud condensation nuclei  

NLE Websites -- All DOE Office Websites (Extended Search)

condensation nuclei condensation nuclei ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Cloud condensation nuclei Small particles (typically 0.0002 mm, or 1/100 th the size of a cloud droplet) about which cloud droplets coalesce. Categories Aerosols, Cloud Properties Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. ARM Instruments AOS : Aerosol Observing System CCN : Cloud Condensation Nuclei Particle Counter Field Campaign Instruments AOS : Aerosol Observing System

427

Cloud Computing: Exploring the scope  

E-Print Network (OSTI)

Cloud computing refers a paradigm shift to overall IT solutions while raising the accessibility, scalability and effectiveness through its enabling technologies. However, migrated cloud platforms and services cost benefits as well as performances are neither clear nor summarized. Globalization and the recessionary economic times have not only raised the bar of a better IT delivery models but also have given access to technology enabled services via internet. Cloud computing has vast potential in terms of lean Retail methodologies that can minimize the operational cost by using the third party based IT capabilities, as a service. It will not only increase the ROI but will also help in lowering the total cost of ownership. In this paper we have tried to compare the cloud computing cost benefits with the actual premise cost which an organization incurs normally. However, in spite of the cost benefits, many IT professional believe that the latest model i.e. "cloud computing" has risks and security concerns. This ...

Pandey, Abhinav; Tandon, Ankit; Maurya, Brajesh Kr; Kushwaha, Upendra

2010-01-01T23:59:59.000Z

428

Cyclotron Resonances in Electron Cloud Dynamics  

SciTech Connect

A new set of resonances for electron cloud dynamics in the presence of a magnetic field has been found. For short beam bunch lengths and low magnetic fields where lb<< 2pi c/omega c (with lb = bunch length, omega c = non-relativistic cyclotron frequency) resonances between the bunch frequency and harmonics of the electron cyclotron frequency cause an increase in the electron cloud density in narrow ranges of magnetic field near the resonances. For ILC parameters the increase in the density is up to a factor ~;;3, and the spatial distribution of the electrons is broader near resonances, lacking the well-defined vertical density"stripes" found for non-resonant cases. Simulations with the 2D computer code POSINST, as well as a single-particle tracking code, were used to elucidate the physics of the dynamics. The existence of the resonances has been confirmed in experiments at PEP-II. The resonances are expected to affect the electron cloud dynamics in the fringe fields of conventional lattice magnets and in wigglers, where the magnetic fields are low. Results of the simulations and experimental observations, the reason for the bunch-length dependence, and details of the dynamics are discussed here.

Celata, C. M.; Furman, Miguel A.; Vay, J.-L.; Ng, J. S.T.; Grote, D. P.; Pivi, M. T. F.; Wang, L. F.

2009-04-29T23:59:59.000Z

429

Zenith Radiance Retrieval of Cloud Properties  

NLE Websites -- All DOE Office Websites (Extended Search)

retrievals of cloud properties retrievals of cloud properties from the AMF/COPS campaign Preliminary retrievals of cloud properties from the AMF/COPS campaign Christine Chiu, UMBC/JCET Alexander Marshak, GSFC Yuri Knyazikhin, Boston University Warren Wiscombe, GSFC Christine Chiu, UMBC/JCET Alexander Marshak, GSFC Yuri Knyazikhin, Boston University Warren Wiscombe, GSFC The cloud optical properties of interest are: The cloud optical properties of interest are: * Cloud optical depth Ď„ - the great unknown * Radiative cloud fraction * Cloud effective drop size, r eff * Cloud optical depth Ď„ - the great unknown * Radiative cloud fraction * Cloud effective drop size, r eff Ď„ = 3 2 LWP r eff r eff in ÎĽm, LWP in g/m 2 The 2-ch narrow-field-of-view radiometer (2NFOV) The 2-ch narrow-field-of-view radiometer

430

Potential Oil Production from the Coastal Plain of the Arctic...  

U.S. Energy Information Administration (EIA) Indexed Site

Potential Oil Production from the Coastal Plain of the Arctic National Wildlife Refuge: Updated Assessment 3. Summary The 1.5 million-acre coastal plain of the 19 million-acre...

431

Arctic Precipitation and Evaporation: Model Results and Observational Estimates  

Science Conference Proceedings (OSTI)

Observational estimates of precipitation and evaporation over the Arctic Ocean and its terrestrial watersheds are compared with corresponding values from the climate model simulations of the Atmospheric Model Intercomparison Project (AMIP). ...

John E. Walsh; Vladimir Kattsov; Diane Portis; Valentin Meleshko

1998-01-01T23:59:59.000Z

432

Arctic Tropospheric Winds Derived from TOVS Satellite Retrievals  

Science Conference Proceedings (OSTI)

Accurate three-dimensional wind fields are essential for diagnosing a variety of important climate processes in the Arctic, such as the advection and deposition of heat and moisture, changes in circulation features, and transport of trace ...

Jennifer A. Francis; Elias Hunter; Cheng-Zhi Zou

2005-07-01T23:59:59.000Z

433

AMOC: Acoustic monitoring of the ocean climate of the Arctic  

Science Conference Proceedings (OSTI)

The overall objective of AMOC is to develop and design an acoustic system for long?term monitoring of the ocean temperature and ice thickness in the Arctic Ocean including the Fram Strait

Ola M. Johannessen; AMOC Group

1999-01-01T23:59:59.000Z

434

Twenty-First-Century Arctic Climate Change in CCSM4  

Science Conference Proceedings (OSTI)

The authors summarize the twenty-first-century Arctic climate simulated by NCAR’s Community Climate System Model, version 4 (CCSM4). Under a strong radiative forcing scenario, the model simulates a much warmer, wetter, cloudier, and stormier ...

Stephen J. Vavrus; Marika M. Holland; Alexandra Jahn; David A. Bailey; Benjamin A. Blazey

2012-04-01T23:59:59.000Z

435

Statistical Characterization of Arctic Polar-Night Jet Oscillation Events  

Science Conference Proceedings (OSTI)

A novel diagnostic tool is presented, based on polar-cap temperature anomalies, for visualizing daily variability of the Arctic stratospheric polar vortex over multiple decades. This visualization illustrates the ubiquity of extended-time-scale ...

Peter Hitchcock; Theodore G. Shepherd; Gloria L. Manney

2013-03-01T23:59:59.000Z

436

Regional Variations of Moist Static Energy Flux into the Arctic  

Science Conference Proceedings (OSTI)

The authors investigate the climmological heating of the Arctic by the atmospheric moist static energy (MSE) flux from lower latitudes based on 25 years (November 1964–1989) of the GFDL dataset. During the five month winter period (NDJFM) the ...

James E. Overland; Philip Turet; Abraham H. Oort

1996-01-01T23:59:59.000Z

437

Autumnal Mixed-Phase Cloudy Boundary Layers in the Arctic  

Science Conference Proceedings (OSTI)

Two mixed-phase cloudy boundary layer events observed over the Arctic ice pack in autumn are extensively analyzed. The local dynamic and thermodynamic structure of the boundary layers is determined from aircraft measurements including analysis of ...

James O. Pinto

1998-06-01T23:59:59.000Z

438

Stratospheric Forcing of Surface Climate in the Arctic Oscillation  

Science Conference Proceedings (OSTI)

Diagnostic results are presented indicating that during the Arctic oscillation surface climate variations are directly forced by changes in the strength of the stratospheric polar vortex. To be specific, large-scale potential vorticity anomalies ...

Robert X. Black

2002-02-01T23:59:59.000Z

439

Intensification of Geostrophic Currents in the Canada Basin, Arctic Ocean  

Science Conference Proceedings (OSTI)

Continuous sampling of upper-ocean hydrographic data in the Canada Basin from various sources spanning from 2003 through 2011 provides an unprecedented opportunity to observe changes occurring in a major feature of the Arctic Ocean. In a 112-km-...

Miles G. McPhee

2013-05-01T23:59:59.000Z

440

A Community Atmosphere Model with Superparameterized Clouds  

SciTech Connect

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

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

2013-06-18T23:59:59.000Z

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


441

DOE Research and Development Accomplishments Tag Cloud  

Office of Scientific and Technical Information (OSTI)

Database Tag Cloud Database Tag Cloud This tag cloud is a specific type of weighted list that provides a quick look at the content of the DOE R&D Accomplishments database. It can be easily browsed because terms are in alphabetical order. With this tag cloud, there is a direct correlation between font size and quantity. The more times a term appears in the bibliographic citations, the larger the font size. This tag cloud is also interactive. Clicking on a term will activate a search for that term. Search results will then be received. absorption Accelerator Accelerators Acid Acids AEC air Alpha Analysis Angular Applications Applied Argonne Aspects atmospheric Atom Atomic atoms Background Basic Batteries Beam Beams Beta Biological Biology BNL Brookhaven Calculations Calvin Capture carbon Cells CH Change changes Chemical Chemistry CHLORINE climate Coal Collisions complex Complexes Compounds computed Computerized conditions Conservation Conversion Cosmic Cosmology Cross Crystal current cycle data Decay density design Detection detectors development Devices Diagnostic Diffraction Dioxide Discovery distribution DNA Effect Effects Efficiency Electric electricity Electromagnetic Electron Electrons Element elementary elements Emission Energy Environmental Equations even Exchange Experiment Experimental experiments Fermi field fields First Fission Fossil Free fuel fuels Fusion Future Gamma Gas Genome global greenhouse group Hadron Health heat Heating heavy high Historical history Human Hydrocarbons Hydrogen Imaging impacts important Information Institute Interaction Interactions International Invariance ion Ions Isotope Isotopes Kinetics large laser Lawrence LBL LBNL lepton level light Linear Lithium Livermore living LLNL long low Magnetic Mass material Materials mathematics Matter Measurement measurements Mechanics mechanism medical Medicine Mesons Metabolism Method methods Model Models Molecular Molecules momentum mu Nambu Neutral Neutrino Neutrinos Neutron neutrons Nuclear Nuclei Nucleon Odd Organic ORNL Oxides oxygen Particle Particles path PET Photosynthesis physical Physics pi Plants Plasma Plutonium Policy Polymers Positron Power problem processes production program Programs progress Properties Proton Protons Quantum Quark Radiation Radioactive Radioisotopes range Ratio ray Reaction Reactions Reactor Reactors Renewable report Research resolution Resonance results Review RTG scattering science Sciences scientific Seaborg Separation Solar Source Sources Space Spectra Spectroscopy spectrum Spin Stability state States storage Strong Structure Studies study supernovae symmetry Symposium Synthesis system Systems Tau technical Techniques technologies Technology Teller Temperature theoretical Theories Theory Therapy Thermal Thermoelectric Thin Time Tomography Top Tracer Transfer Transport type types Upton Uranium uses Velocity Water Weak Wigner yields

442

Design options for an Arctic-class LNG carrier  

SciTech Connect

Melville Shipping Ltd., with Petro-Canada's Arctic pilot project, is designing the first commercial LNG system for year-round operations in the Canadian Arctic. Economical adaptation to the region will be maximized by the design combination of current icebreaking and LNG-transport technologies, with special concentration on the ship's hull form, hull structure and materials, LNG-containment system, and propulsion and transmission systems.

Dick, R.A.; Laskov, V.; Wainwright, J.

1979-01-01T23:59:59.000Z

443

RHIC PRESSURE RISE AND ELECTRON CLOUD.  

SciTech Connect

In RHIC high intensity operation, two types of pressure rise are currently of concern. The first type is at the beam injection, which seems to be caused by the electron multipacting, and the second is the one at the beam transition, where the electron cloud is not the dominant cause. The first type of pressure rise is limiting the beam intensity and the second type might affect the experiments background for very high total beam intensity. In this article, the pressure rises at RHIC are described, and preliminary study results are reported. Some of the unsettled issues and questions are raised, and possible counter measures are discussed.

Zhang, S Y; Blaskiewicz, M; Cameron, P; Drees, P; Afischer, W; Gassner, D; Gullotta, J; He, P; Hseuh, H; Chuang, H; Iriso-Aziz, U; Lee, R; Mackay, W; Woerter, B; Ptitsyn, V; Ponnaiyan, V; Roser, T; Satogata, T; Smart, L; Trbojevic, D

2003-05-12T23:59:59.000Z

444

Mountain Wave–Induced Polar Stratospheric Cloud Forecasts for Aircraft Science Flights during SOLVE/THESEO 2000  

Science Conference Proceedings (OSTI)

The results of a multimodel forecasting effort to predict mountain wave–induced polar stratospheric clouds (PSCs) for airborne science during the third Stratospheric Aerosol and Gas Experiment (SAGE III) Ozone Loss and Validation Experiment (...

Stephen D. Eckermann; Andreas Dörnbrack; Harald Flentje; Simon B. Vosper; M. J. Mahoney; T. Paul Bui; Kenneth S. Carslaw

2006-02-01T23:59:59.000Z

445

Gravity Waves, Compensating Subsidence and Detrainment around Cumulus Clouds  

Science Conference Proceedings (OSTI)

Gravity waves play an important role in the redistribution of heat and moisture in a deep convecting cloud field. We explore this role in a two-dimensional numerical experiment on a simple moist convecting system consisting of an isolated long-...

Christopher S. Bretherton; Piotr K. Smolarkiewicz

1989-03-01T23:59:59.000Z

446

An Eight-Month Sample of Marine Stratocumulus Cloud Fraction, Albedo, and Integrated Liquid Water  

Science Conference Proceedings (OSTI)

As part of the First International Satellite Cloud Climatology Regional Experiment (FIRE), a surface meteorology and shortwave/longwave irradiance station was operated in a marine stratocumulus regime on the northwest tip of San Nicolas island ...

C. W. Fairall; J. E. Hare; J. B. Snider

1990-08-01T23:59:59.000Z

447

The Effect of Clouds on the Earth's Solar and Infrared Radiation Budgets  

Science Conference Proceedings (OSTI)

The effect of global cloudiness on the solar and infrared components of the earth's radiation balance is studied in general circulation model experiments. A wintertime simulation is conducted in which the cloud radiative transfer calculations use ...

Gerald F. Herman; Man-Li C. Wu; Winthrop T. Johnson

1980-06-01T23:59:59.000Z

448

Effect of Cloud-Radiation Feedback on the Climate of a General Circulation Model  

Science Conference Proceedings (OSTI)

The General Circulation Model (GCM) of the Goddard Laboratory for Atmospheric Sciences (GLAS) was integrated for 107 days starting from the initial conditions of 15 May. In this experiment the clouds dynamically generated by the model affect the ...

J. Shukla; Y. Sud

1981-11-01T23:59:59.000Z

449

Numerical Investigations on the Influence of Subgrid-Scale Surface Heterogeneity on Evapotranspiration and Cloud Processes  

Science Conference Proceedings (OSTI)

Numerical experiments were performed with a meso-?-scale meteorological model to investigate the influence of subgrid-scale surface heterogeneity on the prediction of evapotranspiration, cloud, and precipitation formation. The results of ...

Nicole Mölders; Armin Raabe

1996-06-01T23:59:59.000Z

450

Mesoscale Organization and Cloud Microphysics in a Bay of Bengal Depression  

Science Conference Proceedings (OSTI)

Airborne radar and cloud microphysical data were obtained throughout a monsoon depression observed over the Bay of Bengal on 3–8 July 1979 during the Summer Monsoon Experiment of the Global Atmospheric Research Programme. The precipitation in the ...

Robert A. Houze Jr.; Dean D. Churchill

1987-07-01T23:59:59.000Z

451

A Comparison of the Water Budgets between Clouds from AMMA and TWP-ICE  

Science Conference Proceedings (OSTI)

Two field campaigns, the African Monsoon Multidisciplinary Analysis (AMMA) and the Tropical Warm Pool–International Cloud Experiment (TWP-ICE), took place in 2006 near Niamey, Niger, and Darwin, Northern Territory, Australia, providing extensive ...

Xiping Zeng; Wei-Kuo Tao; Scott W. Powell; Robert A. Houze Jr.; Paul Ciesielski; Nick Guy; Harold Pierce; Toshihisa Matsui

2013-02-01T23:59:59.000Z

452

Relative Humidity as an Indicator for Cloud Formation over Heterogeneous Land Surfaces  

Science Conference Proceedings (OSTI)

The influence of land surface heterogeneity on potential cloud formation is investigated using relative humidity as an indicator. This is done by performing numerical experiments using a large-eddy simulation model (LES). The land surface in the ...

Chiel C. van Heerwaarden; Jordi Vilŕ Guerau de Arellano

2008-10-01T23:59:59.000Z

453

Comparisons between Model Forecast and Observed Boundary Layer Profiles and Related Comments on Cloud Prediction  

Science Conference Proceedings (OSTI)

In this study comparisons are made between Met Office mesoscale model boundary layer profiles, and radiosonde data collected in the central United Kingdom during three intensive boundary layer cloud experiments. Significant differences between ...

J. D. Price; M. R. Bush

2004-12-01T23:59:59.000Z

454

LASE Measurements of Water Vapor, Aerosol, and Cloud Distributions in Saharan Air Layers and Tropical Disturbances  

Science Conference Proceedings (OSTI)

The Lidar Atmospheric Sensing Experiment (LASE) on board the NASA DC-8 measured high-resolution profiles of water vapor and aerosols, and cloud distributions in 14 flights over the eastern North Atlantic during the NASA African Monsoon ...

Syed Ismail; Richard A. Ferrare; Edward V. Browell; Gao Chen; Bruce Anderson; Susan A. Kooi; Anthony Notari; Carolyn F. Butler; Sharon Burton; Marta Fenn; Jason P. Dunion; Gerry Heymsfield; T. N. Krishnamurti; Mrinal K. Biswas

2010-04-01T23:59:59.000Z

455

Wavelet Analysis of Simulated Tropical Convective Cloud Systems. Part I: Basic Analysis  

Science Conference Proceedings (OSTI)

A wavelet analysis of a three-dimensional 7-day explicit simulation of the tropical cloud systems in the Global Atmosphere Research Programme (GARP) Atlantic Tropical Experiment Phase III is performed. Three physically distinct regimes (squall ...

Jun-Ichi Yano; Mitchell W. Moncrieff; Xiaoqing Wu; Michio Yamada

2001-04-01T23:59:59.000Z

456

Cloud–Environment Interface Instability: Rising Thermal Calculations in Two Spatial Dimensions  

Science Conference Proceedings (OSTI)

High resolution two-dimensional numerical experiments of rising thermals in a stably stratified environment were performed to study the cloud boundary instability. Unstable modes develop on the leading edge of the rising thermal, which are driven ...

Wojciech W. Grabowski; Terry L. Clark

1991-02-01T23:59:59.000Z

457

Cloud-Environment Interface Instability: Part II: Extension to Three Spatial Dimensions  

Science Conference Proceedings (OSTI)

Three-dimensional numerical experiments were performed with thermals rising in a stably stratified environment to study the cloud-environment boundary instability. This work extends that reported in Part I. It is shown that the analytical theory ...

Wojciech W. Grabowski; Terry L. Clark

1993-02-01T23:59:59.000Z

458

Evolution of the Vertical Mass Flux and Diagnosed Net Lateral Mixing in Isolated Convective Clouds  

Science Conference Proceedings (OSTI)

The evolution of the vertical mass flux in isolated cumulus and cumulus congestus clouds is documented using two King Airs during the Convection and Precipitation/Electrification Experiment (CaPE,), conducted in east-central Florida during the ...

Gary M. Barnes; James C. Fankhauser; Wesley D. Browning

1996-12-01T23:59:59.000Z

459

Laboratory Studies of Scattering Properties of Polluted Cloud Droplets: Implications for FSSP Measurements  

Science Conference Proceedings (OSTI)

Laboratory experiments were conducted in the Mainz vertical wind tunnel to study the effects of pollutants dissolved or suspended in cloud droplets on the droplet size measurements of a Forward Scattering Spectrometer Probe (FSSP). The FSSP is a ...

Karoline Diehl; Günter Huber; Subir K. Mitra; Manfred Wendisch

2008-10-01T23:59:59.000Z

460

Mature Thunderstorm Cloud-Top Structure and Dynamics: A Three-Dimensional Numerical Simulation Study  

Science Conference Proceedings (OSTI)

An anelastic three-dimensional model is used to investigate the effects of vertical wind shear regime on cloud-top structure and internal properties of mature isolated midlatitude thunderstorms. Four comparative experiments, designated A through ...

Robert E. Schlesinger

1984-05-01T23:59:59.000Z

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


461

Determination of Semi-Transparent Cirrus Cloud Temperature from Infrared Radiances: Application to METEOSAT  

Science Conference Proceedings (OSTI)

The use of simultaneous infrared measurements to derive the temperature and emissivity of semi-transparent cirrus clouds is experimentally investigated. Results from the NASA/CONVAIR-990 Winter Experiment Program, 1977 (WEP) are discussed. It is ...

Gerard Szejwach

1982-03-01T23:59:59.000Z

462

Discussion of Intelligent Cloud Computing System  

Science Conference Proceedings (OSTI)

Cloud Computing System (CCS) aims to power the next generation data centers and enables application service providers to lease data center capabilities for deploying applications depending on user Quality of Service (QoS) requirements. Huge investments ... Keywords: cloud computing system, intelligent cloud computing system, data warehouse, cloud computing management information system

Yu Hua Zhang; Jian Zhang; Wei Hua Zhang

2010-10-01T23:59:59.000Z

463

Cloud Droplet Size Distributions in Low-Level Stratiform Clouds  

Science Conference Proceedings (OSTI)

A database of stratus cloud droplet (diameter <50 ?m) size distribution parameters, derived from in situ data reported in the existing literature, was created, facilitating intercomparison among datasets and quantifying typical values and their ...

Natasha L. Miles; Johannes Verlinde; Eugene E. Clothiaux

2000-01-01T23:59:59.000Z

464

AIRS Subpixel Cloud Characterization Using MODIS Cloud Products  

Science Conference Proceedings (OSTI)

The Moderate Resolution Imaging Spectroradiometer (MODIS) and the Atmospheric Infrared Sounder (AIRS) measurements from the Earth Observing System's (EOS's) Aqua satellite enable improved global monitoring of the distribution of clouds. MODIS is ...

Jun Li; W. Paul Menzel; Fengying Sun; Timothy J. Schmit; James Gurka

2004-08-01T23:59:59.000Z

465

Icebergs in the clouds: the other risks of cloud computing  

Science Conference Proceedings (OSTI)

Cloud computing is appealing from management and efficiency perspectives, but brings risks both known and unknown. Well-known and hotly-debated information security risks, due to software vulnerabilities, insider attacks, and side-channels for example, ...

Bryan Ford

2012-06-01T23:59:59.000Z

466

Mixed phase clouds, cloud electrification and remote sensing.  

SciTech Connect

Most of hypothesis trying to explain charge separation in thunderstorm clouds require presence of ice and supercooled water. Thus the existence of ice or at least mixed phase regions near cloud tops should be a necessary (but not a sufficient) condition for development of lightning. We show that multispectral satellite based instruments, like the DOE MTI (Multispectral Thermal Imager) or NASA MODIS (Moderate Resolution Imaging Spectroradiometer), using the near infrared and visible spectral bands are able to distinguish between water, ice and mixed phase cloud regions. An analysis of the MTI images of mixed phase clouds - with spatial resolution of about 20 m - shows regions of pure water, pure ice as well as regions of water/ice mixtures. We suggest that multispectral satellite instruments may be useful for a short time forecast of lightning probabilities.

Chylek, P. (Petr); Borel, C. C. (Christoph C.); Klett, James

2004-01-01T23:59:59.000Z

467

The Role of Cloud Top Entrainment in Cumulus Clouds  

Science Conference Proceedings (OSTI)

The entrainment process and its resultant effects on the microphysics and dynamics within cumuli are not yet clearly understood. This research was undertaken to discover the role which cloud top plays in the entrainment process and to determine ...

Joey F. Boatman; August H. Auer Jr.

1983-06-01T23:59:59.000Z

468

Millimeter Wave Cloud Radar (MMCR) Handbook  

SciTech Connect

The millimeter cloud radar (MMCR) systems probe the extent and composition of clouds at millimeter wavelengths. The MMCR is a zenith-pointing radar that operates at a frequency of 35 GHz. The main purpose of this radar is to determine cloud boundaries (e.g., cloud bottoms and tops). This radar will also report radar reflectivity (dBZ) of the atmosphere up to 20 km. The radar possesses a doppler capability that will allow the measurement of cloud constituent vertical velocities.

KB Widener; K Johnson

2005-01-30T23:59:59.000Z

469

Mission to planet Earth: Role of clouds and radiation in climate  

SciTech Connect

The role of clouds in modifying the earth`s radiation balance is well recognized as a key uncertainty in predicting any potential future climate change. This statement is true whether the climate change of interest is caused by changing emissions of greenhouse gases and sulfates, deforestation, ozone depletion, volcanic eruptions, or changes in the solar constant. This paper presents and overview of the role of the National Aeronautics and Space Administration`s Earth Observing System (EOR) satellite data in understanding the role of clouds in the global climate system. The paper gives a brief summary of the cloud/radiation problem, and discusses the critical observations needed to support further investigation. The planned EOS data products are summarized, including the critical advances over current satellite cloud and radiation budget data. Key advances include simultaneous observation on cloud particle size and phase, improved detection of thin clouds and multilayer cloud systems, greatly reduced ambiguity in partially cloud-filled satellite fields of view, improved calibration and stability of satellite-observed radiances, and improved estimates of radiative fluxes at the top of the atmosphere, at the surface, and at levels within the atmosphere. outstanding sampling and remote sensing issues that effect data quality are also discussed. Finally, the EOS data are placed in the context of other satellite observations as well as the critical surface, field experiment and laboratory data needed to address the role in clouds on the climate system. I is concluded that the EOS data are a necessary but insufficient condition for solution of the scientific cloud/radiation issues. A balanced approach of satellite, field, and laboratory data will be required. These combined data can span the necessary spatial scales of global, regional, cloud cell and cloud particle physics. 137 refs., 12 fig., 4 tab.

Wielicki, B.A.; Harrison, E.F. [NASA Langley Research Center, Hampton, VA (United States)] [and others

1995-11-01T23:59:59.000Z

470

Ocean Heat Transport as a Cause for Model Uncertainty in Projected Arctic Warming  

Science Conference Proceedings (OSTI)

The Arctic climate is governed by complex interactions and feedback mechanisms between the atmosphere, ocean, and solar radiation. One of its characteristic features, the Arctic sea ice, is very vulnerable to anthropogenically caused warming. ...

Irina Mahlstein; Reto Knutti

2011-03-01T23:59:59.000Z

471

An Investigation of an Arctic Front with a Vertically Nested Mesoscale Model  

Science Conference Proceedings (OSTI)

A vertically mesoscale regional numerical weather prediction model is used to simulate an arctic front. The front was observed during the Arctic Cyclone Expedition of 1984. The regional model employs a unique vertical nesting scheme in which the ...

William T. Thompson; Stephen D. Burk

1991-02-01T23:59:59.000Z

472

Mechanisms of Decadal Arctic Climate Variability in the Community Climate System Model, Version 2 (CCSM2)  

Science Conference Proceedings (OSTI)

Several mechanisms have been proposed to explain natural climate variability in the Arctic. These include processes related to the influence of the North Atlantic Oscillation/Arctic Oscillation (NAO/AO), anticyclonic/cyclonic regimes, changes in ...

Hugues Goosse; Marika M. Holland

2005-09-01T23:59:59.000Z

473

The Norwegian IPY–THORPEX: Polar Lows and Arctic Fronts during the 2008 Andřya Campaign  

Science Conference Proceedings (OSTI)

From a weather forecasting perspective, the Arctic poses particular challenges for mainly two reasons: 1) The observational data are sparse and 2) the weather phenomena responsible for severe weather, such as polar lows, Arctic fronts, and orographic ...

J. E. Kristjánsson; I. Barstad; T. Aspelien; I. Fřre; Ř. Godřy; Ř. Hov; E. Irvine; T. Iversen; E. Kolstad; T. E. Nordeng; H. McInnes; R. Randriamampianina; J. Reuder; Ř. Saetra; M. Shapiro; T. Spengler; H. Ólafsson

2011-11-01T23:59:59.000Z

474

Do General Circulation Models Underestimate the Natural Variability in the Arctic Climate?  

Science Conference Proceedings (OSTI)

The authors examine the natural variability of the arctic climate system simulated by two very different models: the Geophysical Fluid Dynamics Laboratory (GFDL) global climate model, and an area-averaged model of the arctic atmosphere–sea ice–...

D. S. Battisti; C. M. Bitz; R. E. Moritz

1997-08-01T23:59:59.000Z

475

DOE/SC-ARM-10-034 The Arctic Lower Troposphere Observed  

NLE Websites -- All DOE Office Websites (Extended Search)

since the late 1960s. Inter-model scatter in projected Arctic temperatures is also an order of magnitude larger in the Arctic than in mid- latitudes. Current climate models do...

476

ARM - Field Campaign - Cloud IOP  

NLE Websites -- All DOE Office Websites (Extended Search)

govCampaignsCloud IOP govCampaignsCloud IOP Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Cloud IOP 1998.04.27 - 1998.05.17 Lead Scientist : Gerald Mace For data sets, see below. Summary Monday, April 27, 1998 IOP Opening Activities: Heavy rain (nearly 2.5" since 12Z 4/26/98) at the central facility (CF) dominated the first day of the Cloud Physics/Single Column Model IOP and limited the daily activities. A 1430 GMT sonde launch commenced the 3-hour sonde launch schedule at the CF and 4 boundary facilities (BFs). Scientists/Instrumentation on Site: Citation: Has arrived and is located at the Ponca City Airport. No flights are currently planned. Flights are tentatively planned for stratus sampling when precipitation ends.

477

Clouds, Aerosols and Precipitation in  

NLE Websites -- All DOE Office Websites (Extended Search)

the Marine Boundary Layer (CAP-MBL) Graciosa Island, Azores, NE Atlantic Ocean Graciosa Island, Azores, NE Atlantic Ocean May 2009-December 2010 May 2009-December 2010 Rob Wood, University of Washington Rob Wood, University of Washington AMF Deployment Team Thanks to Mark Miller: AMF Site Scientist Mark Miller: AMF Site Scientist Kim Nitschke: AMF Site Manager CAP-MBL Proposal Team Importance of Low-Clouds for Climate Imperative that we understand the processes controlling the formation, maintenance and dissipation of low clouds in order to formation, maintenance and dissipation of low clouds in order to improve their representation in climate models. Which clouds matter for climate sensitivity? Cli t F db k

478

NIST Cloud Computing Standards Roadmap  

Science Conference Proceedings (OSTI)

... in this clause is a natural extension to the ... which take advantage of the homogeneity and power of cloud ... such as WS-I) and grid standards (such as ...

2013-08-07T23:59:59.000Z

479

Fractal Statistics of Cloud Fields  

Science Conference Proceedings (OSTI)

Landsat Multispectral Scanner (MSS) and Thematic Mapper (TM) data, with 80 and 30 m spatial resolution, respectively, have been employed to study the spatial structure of boundary-layer and intertropical convergence zone (ITCZ) clouds. The ...

Robert F. Cahalan; Joachim H. Joseph

1989-02-01T23:59:59.000Z

480

Cloud computing for dynamic systems  

Science Conference Proceedings (OSTI)

Cloud computing is a fast emerging model for enabling dynamic on-demand computing and IT-based services. It promotes dynamic properties and characteristics such as scalability, agility, flexibility, virtualised and distributed on-demand computing. However, ...

Khaled Sabry

2011-11-01T23:59:59.000Z

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


481

Breaking the Cloud Parameterization Deadlock  

Science Conference Proceedings (OSTI)

A key factor limiting the reliability of simulations of anthropogenic climate change is the inability to accurately represent the various effects of clouds on climate. Despite the best efforts of the community, the problem has resisted solution ...

David Randall; Marat Khairoutdinov; Akio Arakawa; Wojciech Grabowski

2003-11-01T23:59:59.000Z

482

The Hercules-Aquila Cloud  

E-Print Network (OSTI)

We present evidence for a substantial overdensity of stars in the direction of the constellations of Hercules and Aquila. The Cloud is centered at a Galactic longitude of about 40 degrees and extends above and below the Galactic plane by at least 50 degrees. Given its off-centeredness and height, it is unlikely that the Hercules-Aquila Cloud is related to the bulge or thick disk. More likely, this is a new structural component of the Galaxy that passes through the disk. The Cloud stretches about 80 degrees in longitude. Its heliocentric distance lies between 10 and 20 kpc so that the extent of the Cloud in projection is roughly 20 kpc by 15 kpc. It has an absolute magnitude of -13 and its stellar population appears to be comparable to, but somewhat more metal-rich than, M92.

Belokurov, V; Bell, E F; Irwin, M J; Hewett, P C; Koposov, S; Rockosi, C M; Gilmore, G; Zucker, D B; Fellhauer, M; Wilkinson, M I; Bramich, D M; Vidrih, S; Rix, H W; Beers, T C; Schneider, D P; Barentine, J C; Brewington, H; Brinkmann, J; Harvanek, M; Krzesínski, J; Long, D; Pan, K; Snedden, S A; Malanushenko, O; Malanushenko, V

2007-01-01T23:59:59.000Z

483

The Hercules-Aquila Cloud  

E-Print Network (OSTI)

We present evidence for a substantial overdensity of stars in the direction of the constellations of Hercules and Aquila. The Cloud is centered at a Galactic longitude of about 40 degrees and extends above and below the Galactic plane by at least 50 degrees. Given its off-centeredness and height, it is unlikely that the Hercules-Aquila Cloud is related to the bulge or thick disk. More likely, this is a new structural component of the Galaxy that passes through the disk. The Cloud stretches about 80 degrees in longitude. Its heliocentric distance lies between 10 and 20 kpc so that the extent of the Cloud in projection is roughly 20 kpc by 15 kpc. It has an absolute magnitude of -13 and its stellar population appears to be comparable to, but somewhat more metal-rich than, M92.

V. Belokurov; N. W. Evans; E. F. Bell; M. J. Irwin; P. C. Hewett; S. Koposov; C. M. Rockosi; G. Gilmore; D. B. Zucker; M. Fellhauer; M. I. Wilkinson; D. M. Bramich; S. Vidrih; H. -W. Rix; T. C. Beers; D. P. Schneider; J. C. Barentine; H. Brewington; J. Brinkmann; M. Harvanek; J. Krzesinski; D. Long; K. Pan; S. A. Snedden; O. Malanushenko; V. Malanushenko

2007-01-27T23:59:59.000Z

484

Comparison of an Experimental NOAA AVHRR Cloud Dataset with Other Observed and Forecast Cloud Datasets  

Science Conference Proceedings (OSTI)

CLAVR [cloud from AVHRR (Advanced Very High Resolution Radiometer)] is a global cloud dataset under development at NOAA/NESDIS (National Environmental Satellite, Data, and Information Service). Total cloud amount from two experimental cases, 9 ...

Yu-Tai Hou; Kenneth A. Campana; Kenneth E. Mitchell; Shi-Keng Yang; Larry L. Stowe

1993-12-01T23:59:59.000Z

485

ISCCP Cloud Properties Associated with Standard Cloud Types Identified in Individual Surface Observations  

Science Conference Proceedings (OSTI)

Individual surface weather observations from land stations and ships are compared with individual cloud retrievals of the International Satellite Cloud Climatology Project (ISCCP), stage C1, for an 8-yr period (1983–91) to relate cloud optical ...

Carole J. Hahn; William B. Rossow; Stephen G. Warren

2001-01-01T23:59:59.000Z

486

Biogeography of Tropical Montane Cloud Forests. Part II: Mapping of Orographic Cloud Immersion  

Science Conference Proceedings (OSTI)

This study details two unique methods to quantify cloud-immersion statistics for tropical montane cloud forests (TMCFs). The first technique uses a new algorithm for determining cloud-base height using Moderate Resolution Imaging ...

Udaysankar S. Nair; Salvi Asefi; Ronald M. Welch; D. K. Ray; Robert O. Lawton; Vani Starry Manoharan; Mark Mulligan; Tom L. Sever; Daniel Irwin; J. Alan Pounds

2008-08-01T23:59:59.000Z

487

Cloud-Resolving Simulation of Low-Cloud Feedback to an Increase in Sea Surface Temperature  

Science Conference Proceedings (OSTI)

This study investigates the physical mechanisms of the low cloud feedback through cloud-resolving simulations of cloud-radiative equilibrium response to an increase in sea surface temperature (SST). Six pairs of perturbed and control simulations ...

Kuan-Man Xu; Anning Cheng; Minghua Zhang

2010-03-01T23:59:59.000Z

488

Aircraft Microphysical Documentation from Cloud Base to Anvils of Hailstorm Feeder Clouds in Argentina  

Science Conference Proceedings (OSTI)

Documentation during January and February 2000 of the structure of severe convective storms in Mendoza, Argentina, with a cloud-physics jet aircraft penetrating the major feeder clouds from cloud base to the ?45°C isotherm level is reported. ...

Daniel Rosenfeld; William L. Woodley; Terrence W. Krauss; Viktor Makitov

2006-09-01T23:59:59.000Z

489

Biogeography of Tropical Montane Cloud Forests. Part I: Remote Sensing of Cloud-Base Heights  

Science Conference Proceedings (OSTI)

Cloud-base heights over tropical montane cloud forests are determined using Moderate Resolution Imaging Spectroradiometer (MODIS) cloud products and National Centers for Environmental Prediction global tropospheric final analysis (FNL) fields. ...

Ronald M. Welch; Salvi Asefi; Jian Zeng; Udaysankar S. Nair; Qingyuan Han; Robert O. Lawton; Deepak K. Ray; Vani Starry Manoharan

2008-04-01T23:59:59.000Z

490

The Experimental Cloud Lidar Pilot Study (ECLIPS) for Cloud—Radiation Research  

Science Conference Proceedings (OSTI)

The Experimental Cloud Lidar Pilot Study (ECLIPS) was initiated to obtain statistics on cloud-base height, extinction, optical depth, cloud brokenness, and surface fluxes. Two observational phases have taken place, in October-December 1989 and ...

C. M. Platt; S. A. Young; A. I. Carswell; S. R. Pal; M. P. McCormick; D. M. Winker; M. DelGuasta; L. Stefanutti; W. L. Eberhard; M. Hardesty; P. H. Flamant; R. Valentin; B. Forgan; G. G. Gimmestad; H. Jäger; S. S. Khmelevtsov; I. Kolev; B. Kaprieolev; Da-ren Lu; K. Sassen; V. S. Shamanaev; O. Uchino; Y. Mizuno; U. Wandinger; C. Weitkamp; A. Ansmann; C. Wooldridge

1994-09-01T23:59:59.000Z

491

Estimation of Cloud Physical Parameters from Airborne Solar Spectral Reflectance Measurements for Stratocumulus Clouds  

Science Conference Proceedings (OSTI)

A new method is proposed to retrieve various cloud physical parameters of water clouds from the solar-flux reflectances at four wavelengths measured by using the airborne Multi-channel Cloud Pyranometer (MCP) system. The MCP system was designed ...

Shoji Asano; Masataka Shiobara; Akihiro Uchiyama

1995-10-01T23:59:59.000Z

492

Kinetics of Cloud Drop Formation and Its Parameterization for Cloud and Climate Models  

Science Conference Proceedings (OSTI)

To study the kinetics of drop nucleation in clouds, the integro–differential equation for integral water supersaturation in cloud is derived and analyzed. Solving the supersaturation equation with an algebraic form of the cloud condensation ...

Vitaly I. Khvorostyanov; Judith A. Curry

2008-09-01T23:59:59.000Z

493

Eggs Show Arctic Mercury Cycling May Be Linked to Ice Cover  

Science Conference Proceedings (OSTI)

... cycling of mercury in the Arctic biosphere. Credit: D. Roseneau, US Fish and Wildlife Service View hi-resolution image. ...

2011-01-20T23:59:59.000Z

494

ARM - Field Campaign - Colorado: The Storm Peak Lab Cloud Property  

NLE Websites -- All DOE Office Websites (Extended Search)

govCampaignsColorado: The Storm Peak Lab Cloud Property Validation govCampaignsColorado: The Storm Peak Lab Cloud Property Validation Experiment (STORMVEX) Campaign Links STORMVEX Website Related Campaigns Colorado: CFH/CMH Deployment to StormVEx 2011.02.01, Mace, AMF Colorado: SP2 Deployment at StormVEx 2010.11.15, Sedlacek, AMF Colorado : Cavity Attenuated Phase Shift 2010.11.15, Massoli, AMF Colorado: Infrared Thermometer (IRT) 2010.11.15, Mace, AMF Colorado: StormVEX Aerosol Size Distribution 2010.11.15, Hallar, AMF Colorado: Direct Measurements of Snowfall 2010.11.15, McCubbin, AMF Colorado: Thunderhead Radiative Flux Analysis Campaign 2010.11.15, Long, AMF Colorado: Ice Nuclei and Cloud Condensation Nuclei Characterization 2010.11.15, Cziczo, AMF Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA.

495

An Improved Cloud Classification Algorithm Based on the SGP CART...  

NLE Websites -- All DOE Office Websites (Extended Search)

studies which need to group clouds according to cloud types, but also provides necessary information to implement different retrieval algorithms to generate integrated cloud...

496

A study of the link between cosmic rays and clouds with a cloud chamber at the CERN PS  

E-Print Network (OSTI)

Recent satellite data have revealed a surprising correlation between galactic cosmic ray (GCR) intensity and the fraction of the Earth covered by clouds. If this correlation were to be established by a causal mechanism, it could provide a crucial step in understanding the long-sought mechanism connecting solar and climate variability. The Earth's climate seems to be remarkably sensitive to solar activity, but variations of the Sun's electromagnetic radiation appear to be too small to account for the observed climate variability. However, since the GCR intensity is strongly modulated by the solar wind, a GCR-cloud link may provide a sufficient amplifying mechanism. Moreover if this connection were to be confirmed, it could have profound consequences for our understanding of the solar contributions to the current global warming. The CLOUD (Cosmics Leaving OUtdoor Droplets) project proposes to test experimentally the existence a link between cosmic rays and cloud formation, and to understand the microphysical mechanism. CLOUD plans to perform detailed laboratory measurements in a particle beam at CERN, where all the parameters can be precisely controlled and measured. The beam will pass through an expansion cloud chamber and a reactor chamber where the atmosphere is to be duplicated by moist air charged with selected aerosols and trace condensable vapours. An array of external detectors and mass spectrometers is used to analyse the physical and chemical characteristics of the aerosols and trace gases during beam exposure. Where beam effects are found, the experiment will seek to evaluate their significance in the atmosphere by incorporating them into aerosol and cloud models.

The Cloud Collaboration

2001-04-16T23:59:59.000Z

497

Cloud-state-dependent Sampling in AIRS Observations based on CloudSat Cloud Classification  

Science Conference Proceedings (OSTI)

The precision, accuracy, and potential sampling biases of temperature (T) and water vapor (q) vertical profiles obtained by satellite infrared sounding instruments are highly cloud-state dependent and poorly quantified. We describe progress ...

Qing Yue; Eric J. Fetzer; Brian H. Kahn; Sun Wong; Gerald Manipon; Alexandre Guillaume; Brian Wilson

498

Modeling the subsurface thermal impact of Arctic thaw lakes in a warming climate  

Science Conference Proceedings (OSTI)

Warming air temperatures in the Arctic are modifying the rates of thermokarst processes along Alaska's Arctic Coastal Plain. The Arctic Coastal Plain is dominated by thaw lakes. These kilometer-scale lakes are the most visible surface features in the ... Keywords: MATLAB, Numerical model, Permafrost, Thaw lakes, Thermal model

N. Matell; R. S. Anderson; I. Overeem; C. Wobus; F. E. Urban; G. D. Clow

2013-04-01T23:59:59.000Z

499

Preliminary Geospatial Analysis of Arctic Ocean Hydrocarbon Resources  

SciTech Connect

Ice coverage of the Arctic Ocean is predicted to become thinner and to cover less area with time. The combination of more ice-free waters for exploration and navigation, along with increasing demand for hydrocarbons and improvements in technologies for the discovery and exploitation of new hydrocarbon resources have focused attention on the hydrocarbon potential of the Arctic Basin and its margins. The purpose of this document is to 1) summarize results of a review of published hydrocarbon resources in the Arctic, including both conventional oil and gas and methane hydrates and 2) develop a set of digital maps of the hydrocarbon potential of the Arctic Ocean. These maps can be combined with predictions of ice-free areas to enable estimates of the likely regions and sequence of hydrocarbon production development in the Arctic. In this report, conventional oil and gas resources are explicitly linked with potential gas hydrate resources. This has not been attempted previously and is particularly powerful as the likelihood of gas production from marine gas hydrates increases. Available or planned infrastructure, such as pipelines, combined with the geospatial distribution of hydrocarbons is a very strong determinant of the temporal-spatial development of Arctic hydrocarbon resources. Significant unknowns decrease the certainty of predictions for development of hydrocarbon resources. These include: 1) Areas in the Russian Arctic that are poorly mapped, 2) Disputed ownership: primarily the Lomonosov Ridge, 3) Lack of detailed information on gas hydrate distribution, and 4) Technical risk associated with the ability to extract methane gas from gas hydrates. Logistics may control areas of exploration more than hydrocarbon potential. Accessibility, established ownership, and leasing of exploration blocks may trump quality of source rock, reservoir, and size of target. With this in mind, the main areas that are likely to be explored first are the Bering Strait and Chukchi Sea, in spite of the fact that these areas do not have highest potential for future hydrocarbon reserves. Opportunities for improving the mapping and assessment of Arctic hydrocarbon resources include: 1) Refining hydrocarbon potential on a basin-by-basin basis, 2) Developing more realistic and detailed distribution of gas hydrate, and 3) Assessing the likely future scenarios for development of infrastructure and their interaction with hydrocarbon potential. It would also be useful to develop a more sophisticated approach to merging conventional and gas hydrate resource potential that considers the technical uncertainty associated with exploitation of gas hydrate resources. Taken together, additional work in these areas could significantly improve our understanding of the exploitation of Arctic hydrocarbons as ice-free areas increase in the future.

Long, Philip E.; Wurstner, Signe K.; Sullivan, E. C.; Schaef, Herbert T.; Bradley, Donald J.

2008-10-01T23:59:59.000Z

500

Preliminary Studies on the Variational Assimilation of Cloud-Radiation Observations Using ARM Observations  

NLE Websites -- All DOE Office Websites (Extended Search)

Studies on the Variational Assimilation Studies on the Variational Assimilation of Cloud-Radiation Observations Using ARM Observations M. Janisková, J.-F. Mahfouf, and J.-J. Morcrette European Centre for Medium-Range Weather Forecasts Shinfield Park, Reading Berskshire, United Kingdom Abstract A linearized cloud scheme and a radiation scheme including cloud effects have been developed at European Centre for Medium-Range Weather Forecasts (ECMWF) to assimilate cloud properties in the framework of the four-dimensional variational (4D-Var) assimilation system. To investigate the potential of those schemes to modify the model temperature, humidity and cloud profiles and produce a better match to the observed radiation fluxes, one-dimensional variational (1D-Var) assimilation experiments have been carried out using data from the Atmospheric Radiation Measurement (ARM)