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Sample records for mase-marine stratus experiment-pt

  1. ARM - Field Campaign - 2005 MASE-MArine Stratus Experiment-Pt...

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    would love to hear from you Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : 2005 MASE-MArine Stratus Experiment-Pt. Reyes, CA 2005.07.05 - 2005.07.27 Lead...

  2. Satellite determination of stratus cloud microphysical properties...

    Office of Scientific and Technical Information (OSTI)

    of liquid water path from SSMI, broadband albedo from ERBE, and cloud characteristics from ISCCP are used to study stratus regions. An average cloud liquid water path of ...

  3. Arctic Stratus and Tropical Deep Convection. Integrating Measurements...

    Office of Scientific and Technical Information (OSTI)

    Technical Report: Arctic Stratus and Tropical Deep Convection. Integrating Measurements and Simulations Citation Details In-Document Search Title: Arctic Stratus and Tropical Deep ...

  4. ARM - Field Campaign - MASRAD: Pt. Reyes Stratus Cloud and Drizzle...

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    govCampaignsMASRAD: Pt. Reyes Stratus Cloud and Drizzle Study Campaign Links AMF Point Reyes Website ARM Data Discovery Browse Data Related Campaigns MArine Stratus Radiation...

  5. Albedo and transmittance of inhomogeneous stratus clouds

    SciTech Connect

    Zuev, V.E.; Kasyanov, E.I.; Titov, G.A.

    1996-04-01

    A highly important topic is the study of the relationship between the statistical parameters of optical and radiative charactertistics of inhomogeneous stratus clouds. This is important because the radiation codes of general circulation models need improvement, and it is important for geophysical information. A cascade model has been developed at the Goddard Space Flight Center to treat stratocumulus clouds with the simplest geometry and horizontal fluctuations of the liquid water path (optical thickness). The model evaluates the strength with which the stochastic geometry of clouds influences the statistical characteristics of albedo and the trnasmittance of solar radiation.

  6. ARM - Field Campaign - MArine Stratus Radiation Aerosol and Drizzle...

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    govCampaignsMArine Stratus Radiation Aerosol and Drizzle (MASRAD) IOP Campaign Links Science Plan AMF Point Reyes Website AMF Point Reyes Data Plots ARM Data Discovery Browse Data...

  7. Continental Liquid-phase Stratus Clouds at SGP: Meteorological Influences

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    and Relationship to Adiabacity Continental Liquid-phase Stratus Clouds at SGP: Meteorological Influences and Relationship to Adiabacity Kim, Byung-Gon Kangnung National University Schwartz, Stephen Brookhaven National Laboratory Miller, Mark Brookhaven National Laboratory Min, Qilong State University of New York at Albany Category: Cloud Properties The microphysical properties of continental stratus clouds observed over SGP appear to be substantially influenced by micrometeorological

  8. Analysis of Aerosol Indirect Effects in California Coastal Stratus and Fog

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    Analysis of Aerosol Indirect Effects in California Coastal Stratus and Fog Miller, Mark Brookhaven National Laboratory Kollias, Pavlos Brookhaven National Laboratory Bartholomew, Mary Jane Brookhaven National Laboratory Daum, Peter Brookhaven National Laboratory Dunn, Maureen Brookhaven National Laboratory Jensen, Michael Brookhaven National Laboratory Liu, Yangang Brookhaven National Laboratory Vogelmann, Andrew Brookhaven National Laboratory Andrews, Betsy NOAA/CMDL Ogren, John NOAA/CMDL

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

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    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- tions taken from the 2004

  10. Equations Governing Space-Time Variability of Liquid Water Path in Stratus Clouds

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    Equations Governing Space-Time Variability of Liquid Water Path in Stratus Clouds K. Ivanova Pennsylvania State University University Park, Pennsylvania T. P. Ackerman Pacific Northwest National Laboratory Richland, Washington M. Ausloos University of Liège B-4000 Liège, Belgium Abstract We present a method on how to derive an underlying mathematical (statistical or model free) equation for a liquid water path (LWP) signal directly from empirical data. The evolution of the probability density

  11. Development and testing of an aerosol-stratus cloud parameterization scheme for middle and high latitudes

    SciTech Connect

    Olsson, P.Q.; Meyers, M.P.; Kreidenweis, S.; Cotton, W.R.

    1996-04-01

    The aim of this new project is to develop an aerosol/cloud microphysics parameterization of mixed-phase stratus and boundary layer clouds. Our approach is to create, test, and implement a bulk-microphysics/aerosol model using data from Atmospheric Radiation Measurement (ARM) Cloud and Radiation Testbed (CART) sites and large-eddy simulation (LES) explicit bin-resolving aerosol/microphysics models. The primary objectives of this work are twofold. First, we need the prediction of number concentrations of activated aerosol which are transferred to the droplet spectrum, so that the aerosol population directly affects the cloud formation and microphysics. Second, we plan to couple the aerosol model to the gas and aqueous-chemistry module that will drive the aerosol formation and growth. We begin by exploring the feasibility of performing cloud-resolving simulations of Arctic stratus clouds over the North Slope CART site. These simulations using Colorado State University`s regional atmospheric modeling system (RAMS) will be useful in designing the structure of the cloud-resolving model and in interpreting data acquired at the North Slope site.

  12. Island based radar and microwave radiometer measurements of stratus cloud parameters during the Atlantic Stratocumulus Transition Experiment (ASTEX)

    SciTech Connect

    Frisch, A.S.; Fairall, C.W.; Snider, J.B.; Lenshow, D.H.; Mayer, S.D.

    1996-04-01

    During the Atlantic Stratocumulus Transition Experiment (ASTEX) in June 1992, simultaneous measurements were made with a vertically pointing cloud sensing radar and a microwave radiometer. The radar measurements are used to estimate stratus cloud drizzle and turbulence parameters. In addition, with the microwave radiometer measurements of reflectivity, we estimated the profiles of cloud liquid water and effective radius. We used radar data for computation of vertical profiles of various drizzle parameters such as droplet concentration, modal radius, and spread. A sample of these results is shown in Figure 1. In addition, in non-drizzle clouds, with the radar and radiometer we can estimate the verticle profiles of stratus cloud parameters such as liquid water concentration and effective radius. This is accomplished by assuming a droplet distribution with droplet number concentration and width constant with height.

  13. Atmospheric Radiation Measurement (ARM) Data from Point Reyes, California for the Marine Stratus, Radiation, Aerosol, and Drizzle (MASRAD) Project

    DOE Data Explorer

    Point Reyes National Seashore, on the California coast north of San Francisco, was the location of the first deployment of the DOE's Atmospheric Radiation Measurement (ARM) Mobile Facility (AMF). The ARM Program collaborated with the U.S. Office of Naval Research and DOE's Aerosol Science Program in the Marine Stratus, Radiation, Aerosol, and Drizzle (MASRAD) project. Their objectives were to collect data from cloud/aerosol interactions and to improve understanding of cloud organization that is often associated with patches of drizzle. Between March and September 2005, the AMF and at least two research aircraft were used to collect data.

  14. sgp_stratus_poster_v1.0.ppt

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    (Energy Information Administration/Short-Term Energy Outlook -- September 2001) 1 Short-Term Energy Outlook September 2001 Overview Natural Gas Markets The U.S. economic slowdown and the lack of any sustained and broad-based boost in fuel use from summer electricity demand have left U.S. natural gas supplies underwhelmed on the demand side since the end of the last heating season. At the end of August, working gas in storage amounted to approximately 2,603 billion cubic feet, 19 percent above

  15. Stratus Cloud Drizzle Retrieval During SHEBA from MMCR Doppler...

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    26 132 dBZ 3 D 1 2 x + - - > < the droplet concentration as 1 3 e w 2 x q r 4 3 xp 3 N and the liquid water flux as ( ) ( ) a b 3 exp a b V q F 2 x D 1 q...

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

    SciTech Connect

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

    2008-02-18

    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.

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

    SciTech Connect

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

    2009-04-10

    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.

  18. Stratus Cloud Structure from MM-Radar Transects and Satellite Images: Scaling Properties and Artifact Detection with Semi-...

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    Structure from mm-Radar Transects and Satellite Images: Scaling Properties and Artifact Detection with Semi-Discrete Wavelet Analyses A. B. Davis Space and Remote Sensing Sciences Group Los Alamos National Laboratory Los Alamos, New Mexico N. P. Petrov Department of Physics The University of Texas Austin, Texas E. E. Clothiaux Department of Meteorology The Pennsylvania State University University Park, Pennsylvania A. Marshak Climate and Radiation Branch National Aeronautics and Space

  19. gottschalck(2)-99.PDF

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    Mesoscale Variability of a Continental Stratus Cloud Event at the SGP CART Site During 1999 J. C. Gottschalck and B. A. Albrecht University of Miami Miami, Florida Introduction Current observational data bases of continental stratus are mainly composed of observations from a single location. It has been shown, however, that marine stratus decks show both mesoscale and diurnal variability (Albrecht et al. 1988; Albrecht et al. 1995; Miller and Albrecht 1995; Miller et al. 1998). Such variability

  20. Atmospheric Radiation Measurement (ARM) Data from Point Reyes, California

    Office of Scientific and Technical Information (OSTI)

    for the Marine Stratus, Radiation, Aerosol, and Drizzle (MASRAD) Project () | Data Explorer Point Reyes, California for the Marine Stratus, Radiation, Aerosol, and Drizzle (MASRAD) Project Title: Atmospheric Radiation Measurement (ARM) Data from Point Reyes, California for the Marine Stratus, Radiation, Aerosol, and Drizzle (MASRAD) Project Point Reyes National Seashore, on the California coast north of San Francisco, was the location of the first deployment of the DOE's Atmospheric

  1. ARM - Publications: Science Team Meeting Documents

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    Stratus Microphysical Parameters Using Radar and Visible Optical Depth Austin, R.T. and Stephens, G.L., Colorado State University, Fort Collins Eleventh Atmospheric Radiation Measurement (ARM) Science Team Meeting A new algorithm for the retrieval of stratus cloud microphysical parameters was introduced last year and applied to measurements of maritime stratus clouds off the coast of California. The retrieval has been refined and applied to data from the Southern Great Plains CART site, as well

  2. ARM - Publications: Science Team Meeting Documents

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    Six-Year Climatology of Continental Stratus - Boundary Layer and Macroscopic Cloud Characteristics Kollias, P.(a), Zhu, P.(b), Gottschalck, J.(c), and Albrecht, B.(a), University of Miami (a), University of Washington (b), NASA (c) Thirteenth Atmospheric Radiation Measurement (ARM) Science Team Meeting A climatology of macroscopic cloud and environmental properties of continental stratus is developed for continental stratus. Results are obtained by using data collected from 1997-2002 at the

  3. Research Highlight

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    Arctic stratus clouds: Sensitivity to ice initiation mechanisms." Atmospheric Chemistry and Physics Discussion 8: 11755-11819. The vertical structure and radiative...

  4. Newsletter Southern Great Plains

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    world, including China, Japan, Australia, Niger, Africa, France, and Germany. ... the following results: * High-quality data sets of fair-weather cumulus, stratus, and deep ...

  5. ARM - Measurement - Cloud phase

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    that involves property descriptors such as stratus, cumulus, and cirrus. Categories Cloud Properties Instruments The above measurement is considered scientifically relevant for the...

  6. ARM - Measurement - Cloud type

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    Measurement : Cloud type Cloud type such as cirrus, stratus, cumulus etc Categories Cloud Properties Instruments The above measurement is considered scientifically relevant for the...

  7. 1

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    Objective Synoptic Classification of Stratus: Impact on Macroscopic Cloud Statistics J. C. Gottschalck, B. A. Albrecht, and P. Kollias University of Miami Miami, Florida ...

  8. kollias-98.pdf

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    High Resolution Doppler Radar Observations in Continental Stratus Clouds P. Kollias and B. A. Albrecht University of Miami Miami, Florida Introduction Vertical mixing is a key ...

  9. ARM - Campaign Instrument - qcsfcrad

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    Campaigns MArine Stratus Radiation Aerosol and Drizzle (MASRAD) IOP Download Data Point Reyes CA, USA; Mobile Facility (MASRAD), 2005.03.14 - 2005.09.14 Primary Measurements ...

  10. ARM - Field Campaign - MASRAD - Aerosol Optical Properties

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    govCampaignsMASRAD - Aerosol Optical Properties Campaign Links AMF Point Reyes Website ARM Data Discovery Browse Data Related Campaigns MArine Stratus Radiation Aerosol and Drizzle...

  11. X:\\ARM_19~1\\PG93-112.WPD

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    files of stratus cloud parameters such as liquid water concentration and effective radius. ... The top panel shows the temporal lag and the bottom panel the spatial lag. Sampling is ...

  12. 1

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    Effect of Stratus on Solar Radiation: A Study Using Millimeter Wave Cloud Radar and Microwave Radiometer Data From the Southern Great Plains M. Sengupta and T. P. Ackerman Pacific ...

  13. chin-98.pdf

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    the marine oceans and the islands (e.g., Albrecht et al. 1985; Nicholls and Leighton 1986; ... 1986); squares, marine stratocumulus (Albrecht et al. 1985); asterisk, stratus over the ...

  14. Section 77

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    Observational Studies of Continental Stratus-Implications for Modeling B. A. Albrecht ... to that of systems that are observed frequently over the oceans (Albrecht et al. 1995a,b). ...

  15. ARM - Campaign Instrument - mpl

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    MASRAD: Pt. Reyes Stratus Cloud and Drizzle Study Download Data Point Reyes CA, USA; Mobile Facility (MASRAD), 2005.07.07 - 2005.07.31 MPL Measurements, Norwegian Young sea ICE ...

  16. ARM - Campaign Instrument - rwp

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    MASRAD: Pt. Reyes Stratus Cloud and Drizzle Study Download Data Point Reyes CA, USA; Mobile Facility (MASRAD), 2005.07.07 - 2005.07.31 Midlatitude Continental Convective Clouds ...

  17. ARM - Campaign Instrument - mmcr94miami

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    MArine Stratus Radiation Aerosol and Drizzle (MASRAD) IOP Download Data Point Reyes CA, USA; Mobile Facility (MASRAD), 2005.03.14 - 2005.09.14 Spring Cloud IOP Download Data ...

  18. ARM - Campaign Instrument - swfluxanal

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    Campaigns MArine Stratus Radiation Aerosol and Drizzle (MASRAD) IOP Download Data Point Reyes CA, USA; Mobile Facility (MASRAD), 2005.03.14 - 2005.09.14 Mixed-Phase Arctic ...

  19. ARM - Field Campaign - MASRAD: Cloud Study from the 2NFOV at...

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    govCampaignsMASRAD: Cloud Study from the 2NFOV at Pt. Reyes Field Campaign Campaign Links AMF Point Reyes Website ARM Data Discovery Browse Data Related Campaigns MArine Stratus...

  20. zhang(1)-98.pdf

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    7 The Influence of Radiation and Large-Scale Vertical Motion on the Persistence of Arctic Stratus Clouds Q. Zhang and K. Stamnes Geophysical Institute University of Alaska Fairbanks, Alaska D. K. Lilly Cooperative Institute for Meteorological Satellite Studies University of Oklahoma Boulder, Oklahoma Introduction Arctic Stratus Clouds (ASCs) are important modulators of local climate, and perhaps even global climate. One of the most significant features of ASC is that they can persist for several

  1. zhang(2)-98.pdf

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    3 Formation of Arctic Stratus Clouds: Comparison of Model Predictions with Observed Cloud Structure Q. Zhang and K. Stamnes Geophysical Institute University of Alaska Fairbanks, Alaska O. Lie-Svendsen Norwegian Defense Research Establishment Kjeller, Norway Introduction The importance of the Arctic region to global climate has been highlighted by the climate modeling results in recent years (e.g., Manabe et al. 1991). Arctic stratus clouds (ASC) are not only one of the most significant regional

  2. zhang-q-99.PDF

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    Study of the Formation of Single- and Multiple-Layered Arctic Stratus Clouds Q. Zhang University of Utah Salt Lake City, Utah K. Stamnes and J. Harrington Geophysical Institute University of Alaska Fairbanks, Alaska O. Lie-Svendsen Norwegian Defense Research Establishment Kjeller, Norway Introduction Arctic stratus clouds (ASCs) are a persistent feature in the arctic. They may have an important influence on both the local climate and the global climate. Due to lack of observations, the formation

  3. Microsoft PowerPoint - ARM08_hguo_080229.ppt

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    3D simulations of stratiform clouds during the MASRAD and MASE Experiments H. Guo, Y. Liu, and P. H. Daum Atmospheric Sciences Division, Brookhaven National Laboratory leg2 leg2 leg2 leg2 Contact: hguo@bnl.gov (631) 344 3829 References (1) Daum, P. et al., Microphysical properties of stratus/stratocumulus clouds during the 2005 Marine stratus/stratocumulus Experiment (MASE), revised, 2008 (2) Tao, W. et al., Microphysics, radiation, and surface processes in the Goddard Cumulus Ensemble (GCE)

  4. Microsoft PowerPoint - poster for ARM 2007 5

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    process in single-layer arctic stratus during MPACE Gong Zhang 1 , Greg McFarquhar 1 , Johannes Verlinde 2 , Michael Poellot 3 , Greg Kok 4 , Edwin Eloranta 5 , Paul DeMott 6 , Tony Prenni 6 and Andrew Heymsfield 7 1 University of Illinois 2 Pennsylvania State University 3 University of North Dakota 4 Droplet Measurement Technologies 5 University of Wisconsin 6 Colorado State University 7 National Center for Atmospheric Research 1 Arctic boundary single-layer stratus 2 Vertical cloud structure

  5. gottschalck(1)-99

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    Macroscopic Cloud and Boundary Layer Properties for Continental Stratus at the SGP CART Site During 1997 J. C. Gottschalck and B. A. Albrecht University of Miami Miami, Florida Introduction Stratus and stratocumulus clouds are important in the regulation of the earth's radiation budget and thus play an important role in climate over both the land and ocean (Ramanathan et al. 1989). Consequently, there is a great need for accurate boundary layer cloud parameterizations in climate models (Slingo

  6. PowerPoint Presentation

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    Aerosol Indirect Effects in California Coastal Stratus and Fog SUMMARY Data from the AMF deployment during MASRAD can be used to directly test the performance of existing cloud droplet nucleation parameterizations in coastal stratus clouds. The example below is a test of Twomey's 1959 parameterization. More sophisticated parameterizations have been formulated and will be tested in a similar manner. 3. Air Mass Source Analysis The HYbrid Single-Particle Lagrangian Integrated Trajectory model

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

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    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

  8. Austin(2)-RT

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    Stratus Sensing in the CloudSat Antecedent Validation Experiment (CAVEX99) R. T. Austin, G. L. Stephens, R. F. McCoy, Jr., R. B. McCoy, and S. D. Miller Department of Atmospheric Science Colorado State University Fort Collins, Colorado S. M. Sekelsky Microwave Remote Sensing Laboratory University of Massachusetts Amherst, Massachusetts Introduction The CloudSat Antecedent Validation Experiment (CAVEX99) was one component of the Monterey Coastal Stratus Experiment (MCSE), a multi-experiment study

  9. Kato-S

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    Doppler Radar and Microwave Radiometer Derived Stratus Cloud Particle Size Distributions S. Kato Center for Atmospheric Sciences Hampton University Hampton, Virginia G. G. Mace Department of Meteorology University of Utah Salt Lake City, Utah E. E. Clothiaux Department of Meteorology The Pennsylvania State University University Park, Pennsylvania J. C. Liljegren Argonne National Laboratory Argonne, Illinois Introduction Some earlier studies demonstrate that the size distribution of stratus cloud

  10. ARM - Field Campaign - Summer UAV Campaign

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    govCampaignsSummer UAV Campaign Campaign Links ARM UAV Program Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Summer UAV Campaign 1999.06.01 - 1999.07.31 Lead Scientist : Tim Tooman Abstract During the Monterey Coastal Stratus Experiment (MCSE), maritime stratus cloud properties were studied in Monterey Bay, California. http://armuav.ca.sandia.gov/uavsu99/uavsu99.html

  11. ARM - Publications: Science Team Meeting Documents

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    Arctic Stratus Cloud Properties and Radiaitve Forcing Derived From Ground-Based Data Collected at ARM NSA Site and SHEBA Ship Dong, X. and Mace, G.G., University of Utah Twelfth Atmospheric Radiation Measurement (ARM) Science Team Meeting A record of single-layer and overcast low-level Arctic stratus cloud properties has been generated using data collected at the Atmospheric Radiation Measurement site near Barrow, Alaska from May to September 2000. The record includes liquid-phase and liquid

  12. ARM - Publications: Science Team Meeting Documents

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    Mesoscale Model Investigations of the Lifecycles of Arctic Mixed-Phase Stratus Avramov, A., Harrington, J.Y., Verlinde, J., and Clothiaux, E.E., The Pennsylvania State University(a) Fourteenth Atmospheric Radiation Measurement (ARM) Science Team Meeting Although Arctic clouds play an important role in Arctic climate system, they remain one of the least understood cloud systems. In particular, mixed-phase arctic stratus clouds which are the predominant cloud type in the Arctic, and therefore

  13. ARM - Publications: Science Team Meeting Documents: Atmospheric Modes of

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    Drizzling Stratus at the ARM SGP Site Atmospheric Modes of Drizzling Stratus at the ARM SGP Site Kollias, Pavlos RSMAS/University of Miami Albrecht, Bruce University of Miami The representation of boundary layer clouds in GCMs remains a source of uncertainty in climate simulations. The cloud amount in the boundary layer is sensitive to the boundary layer scheme. Furthermore, little is known on the climatology of drizzling or precipitating boundary layer clouds, their seasonal variability and

  14. ARM - Publications: Science Team Meeting Documents: Liquid water path

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    estimates in marine stratus Liquid water path estimates in marine stratus Zuidema, Paquita RSMAS/MPO University of Miami Fairall, Chris NOAA/Environmental Technology Laboratory Westwater, Ed University of Colorado/CIRES Hazen, Duane NOAA/Environmental Technology Laboratory We examine liquid water paths (LWPs) derived from ship-based microwave radiometer brightness temperature ($T_b$) measurements collected in overcast, well-mixed boundary layer conditions within the southeastern Pacific. 3

  15. ARM - Publications: Science Team Meeting Documents: The First Deployment of

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    the ARM Mobile Facility; Investigating Marine Stratus at Pt. Reyes, CA The First Deployment of the ARM Mobile Facility; Investigating Marine Stratus at Pt. Reyes, CA Bartholomew, Mary Jane Brookhaven National Laboratory Miller, Mark Brookhaven National Laboratory Bucholtz, Anthony Naval Research Laboratory Albrecht, Bruce University of Miami Kollias, Pavlos RSMAS/University of Miami Sisterson, Douglas Argonne National Laboratory Widener, Kevin Pacific Northwest National Laboratory Jones,

  16. Microsoft PowerPoint - gongposter_for_ARM_2008_4

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    properties of arctic boundary-layer stratus: impacts on surface radiation Gong Zhang and Greg McFarquhar University of Illinois at Urbana-Champaign Introduction Acknowledgments This research was supported by the Office of Science (BER), U.S. DOE, Grant Numbers DE-FG02-02ER63337 and DE-FG02- 07ER64378. FIG 1 Backscatter intensity and depolarization ratio measured by Wisconsin HSRL lidar in Barrow, AK show optically thick boundary-layer stratus between 5 and 12 Oct. 2004. Optically-thick

  17. ARM - Publications: Science Team Meeting Documents

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    Comparison of Stratus Cloud Properties Deduced from Surface, GOES, and Aircraft Data During the March 2000 ARM Cloud IOP Dong, X.(a), Minnis, P.(b), Mace, G.G.(c), Smith, W.L., Jr.(b), Marchand, R.T.(d), and Rapp, A.D.(e), University of North Dakota (a), NASA Langley Research Center (b), University of Utah (c), Pacific Northwest National Laboratory (d), AS&M, Inc. (e) Thirteenth Atmospheric Radiation Measurement (ARM) Science Team Meeting Low-level stratus cloud microphysical properties

  18. ARM - VAP Product - mmcrmode01v0041cloth

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    41cloth Documentation Data Management Facility Plots (Quick Looks) Citation DOI: 10.5439/1027301 [ What is this? ] Generate Citation 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 VAP Output : MMCRMODE01V0041CLOTH ARSCL: derived, MMCR Mode 1 (stratus mode) moments (4/97-9/97) Active Dates 1997.04.01 - 1997.09.1

  19. ARM - VAP Product - mmcrmode01v0051cloth

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    51cloth Documentation Data Management Facility Plots (Quick Looks) Citation DOI: 10.5439/1027302 [ What is this? ] Generate Citation 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 VAP Output : MMCRMODE01V0051CLOTH ARSCL: derived, MMCR Mode 1 (stratus mode) moments (12/96-2/97) Active Dates 1996.12.02 - 1997.02.2

  20. wangz-98.pdf

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    1 Ozone Destruction in Continental Stratus Clouds: Experimental Evidence for Heterogeneous Chemistry Z. Wang and K. Sassen Department of Meteorology University of Utah Salt Lake City, Utah Introduction There is considerable interest in studying tropospheric ozone because of its role as a greenhouse gas and as a key element in tropospheric chemistry. Heterogeneous chem- istry involving reactions with aerosols and cloud droplets can affect O 3 in a number of ways. The results of model studies show

  1. Microsoft PowerPoint - ShupeARM2007.ppt [Compatibility Mode]

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    and Microphysics in Arctic Mixed-Phase Stratus Matthew Shupe With contributions from Pavlos Kollias, Ed Luke, Ola Persson, Greg McFarquhar, Michael Poellot, Ed Eloranta g q , , John Daniel, Gijs DeBoer, Chuck Long, Dave Turner Hans Verlinde, Amy Solomon ARM Science Team Meeting 2007 Topics Status of Ground-Based Observational Methods Observational Methods Cloud Classification Cloud Classification M-PACE M PACE Vertical Motions & Microphysics p y A Conceptual Model p Status of Ground-based

  2. Lesson Plan

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    K-2 Common Covering Clouds http://education.arm.gov Common Covering Clouds: Grades K-2 1 Common Covering Clouds Approximate Time 1 1/2 hours, or two 45-minute segments Objective The student will investigate and demonstrate understanding of common clouds as evidenced by completion of activity. Key Points to Understand * There are many types of clouds, including cirrus, cumulus, stratus, cirrocumulus, altocumulus, stratocumulus, cumulonimbus, and altostratus. * Clouds influence weather. * Weather

  3. Research Highlight

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    CCN and Vertical Velocity Influences Submitter: Hudson, J. G., Desert Research Institute Area of Research: Cloud-Aerosol-Precipitation Interactions Working Group(s): Cloud-Aerosol-Precipitation Interactions Journal Reference: Hudson JG and S Noble. 2013. "CCN and vertical velocity influences on droplet concentrations and supersaturations in clean and polluted stratus clouds." Journal of the Atmospheric Sciences, 71(1), 10.1175/JAS-D-13-086.1. Figure 1. Effective cloud supersaturation

  4. Research Highlight

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    A Radiation Closure Study at Both Surface and TOA Using RTM PI Contact: Dong, X., University of Arizona Area of Research: Radiation Processes Working Group(s): Radiative Processes Journal Reference: Dong X, B Xi, S Qiu, P Minnis, S Sun-Mack, and F Rose. 2016. "A radiation closure study of Arctic stratus cloud microphysical properties using the collocated satellite-surface data and Fu-Liou radiative transfer model." Journal of Geophysical Research - Atmospheres, 121(17),

  5. kollias-99.PDF

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    Mass Flux Representations of Vertical Velocity Fluctuations in Continental Stratus Clouds Using a mm-Wavelength Doppler Radar P. Kollias and B. A. Albrecht University of Miami Miami, Florida Introduction A cloud mass flux representation of the vertical turbulent fluxes provides a physical framework for understanding the effects of shallow convection in maintaining the vertical structure of the boundary layer. This approach is based on the assumption that coherent updrafts and downdraft

  6. leoles_poster_v1.0.ppt

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    Observations and LES of Liquid Stratus over the ACRF D. B. Mechem and Y. L. Kogan Cooperative Institute for Mesoscale Meteorological Studies, The University of Oklahoma The evolution of low cloud systems is inextricably linked to dynamical processes: heat, moisture, mass, and momentum transports, and of course, entrainment. Studies employing continuous years of low cloud observations over the southern great plains ARM Climate Research Facility (ACRF) emphasized their climatological,

  7. Posters

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    9 Posters Stratus Cloud Measurements with a K α -Band Doppler Radar and a Microwave Radiometer A. S. Frisch, C. W. Fairall, and J. B. Snider National Oceanic and Atmospheric Administration Environmental Technology Laboratory Boulder, Colorado D. H. Lenschow National Center for Atmospheric Research Boulder, Colorado The goal of the Atlantic Stratocumulus Transition Experiment (ASTEX) held in the North Atlantic during June 1992 was to determine the physical reasons for the transition from

  8. Posters

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    3 Posters The Effects of Arctic Stratus Clouds on the Solar Energy Budget in the Atmosphere-Sea Ice-Ocean System Z. Jin and K. Stamnes Geophysical Institute University of Alaska Fairbanks, Alaska B. D. Zak Sandia National Laboratories Albuquerque, New Mexico Radiative Transfer Model We have developed a comprehensive radiative transfer model pertinent to the atmosphere-sea ice-ocean system (Jin and Stamnes 1994; Jin et al., in press). The main features of the newly-developed radiative transfer

  9. Posters

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    Posters Development of a Hybrid Cloud Parameterization for General Circulation Models C.-Y. J. Kao, J. E. Kristjansson, and D. L. Langley Earth and Environmental Sciences Division Los Alamos National Laboratory Los Alamos, New Mexico Introduction We have developed a cloud package with state-of-the-art physical schemes that can parameterize low-level stratus or stratocumulus, penetrative cumulus, and high-level cirrus. Such parameterizations will improve cloud simulations in general circulation

  10. Pt Reyes 2005: MASRAD, MASE

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    Stratus Radiation, Aerosol, and Drizzle MASRAD, MASE Graham Feingold, A. McComiskey M. Miller * , D. Turner, P. Daum, J. Seinfeld, J. Ogren Q. Min, C. Berkowitz, J. Wang, E. Andrews, C. Chiu, M. Jensen, N. Riemer , J. Ching, L. Berg, A. S. Frisch, M. Bartholomew, B. Kim, M. Dunn, P. Kollias, B. Albrecht, ....... Pt. Reyes, California *PI Motivation: Strong shortwave cloud forcing (dark underlying ocean) No compensating longwave forcing Open cells Pockets of open cells Closed cells Science Goals

  11. Radiosonde observations at Pt. Reyes and cloud properties retrieved from

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    GOES-WEST Radiosonde observations at Pt. Reyes and cloud properties retrieved from GOES-WEST Inoue, Toshiro MRI/JMA Category: Field Campaigns Low-level cloud formed off the west coast of continents plays an important role in general circulation and climate. Marine Stratus Radiation Aerosol and Drizzle (MASRAD) was conducted at the ARM mobile site deployed at Pt Reyes, California during April to September. Here, we studied the relationship between meteorological parameters observed by GPS

  12. Research Highlight

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    Profiling Capability of High-Resolution Oxygen A-band Spectroscopy for Stratus Cloud Cover Submitter: Davis, A. B., Jet Propulsion Laboratory Area of Research: Cloud Distributions/Characterizations Working Group(s): Cloud Properties Journal Reference: Davis AB, IN Polonsky, and A Marshak. 2009. Space-Time Green Functions for Diffusive Radiation Transport, in Application to Active and Passive Cloud Probing. In Light Scattering Reviews, Volume 4, pp. 169-292. Ed. by A.A. Kohkanovsky, Heidelberg,

  13. Microsoft Word - Poellot-MR.doc

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    Measurements of Cloud Liquid Water Over the SGP Site M. R. Poellot University of North Dakota Grand Forks, North Dakota R. T. Marchand Pacific Northwest National Laboratory Richland, Washington C. Twohy Oregon State University Corvallis, Oregon Introduction The University of North Dakota Citation aircraft made in situ measurements of liquid water clouds on six flights in stratus clouds during the Spring 2000 Cloud Intensive Operational Period (IOP) at the Southern Great Plains (SGP) site. Four

  14. Khaiyer.ARM.07.ppt

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    GOES-10 Satellite-derived Cloud and Radiative Properties for the MASRAD ARM Mobile Facility Deployment M. M. Khaiyer, D. R. Doelling, R. Palikonda, M.L.Nordeen Science Systems and Applications Inc, Hampton, VA P. Minnis NASA Langley Research Center, Hampton, VA 1.Introduction The ARM Mobile Facility (AMF) deployment at Pt Reyes, CA as part of the Marine Stratus Radiation Aerosol and Drizzle experiment (MASRAD), 14 March -14 September 2005 provided an excellent chance to validate satellite

  15. Kogan-ZN

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    Drop Effective Radius for Drizzling Marine Stratus in Global Circulation Models Z. N. Kogan and Y. L. Kogan Cooperative Institute for Mesoscale Meteorological Studies University of Oklahoma Norman, Oklahoma Introduction The cloud drop effective radius, R e , is one of the most important parameters in calculations of cloud radiative properties. Numerous formulations of the effective radius have been developed for use in numerical models (see, e.g., review in Gultepe et al. 1996); however, to the

  16. Hierarchical Diagnosis

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    Development of a Rad iative Cloud Parameterization Scheme of Stratocumulus and Stratus Clouds Which Includes the Impact of Cloud Condensation Nucleus on Cloud Albedo W. R. Cotton, G. L. Stephens, D. Duda, B. Stevens, and R. L. Walko Colorado State University Department of Atmospheric Science Fort Collins, CO G. Feingold Cooperative Institute for Research in Environmental Sciences University of Colorado, Boulder Boulder. CO 80309-0049 A three-dimensional (3-D) model for simulating the effect of

  17. Hierarchical Diagnosis R. A. Kropfli, S. Y. Matrosov, T. Uttal, and B. W. Orr

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    R. A. Kropfli, S. Y. Matrosov, T. Uttal, and B. W. Orr National Oceanic and Atmospheric Administration/Environmental Research Laboratories Wave Propagation Laboratory Boulder, CO 80303 I ntrod uction The WPL 8-mm wavelength radar was designed with good sensitivity and resolution to observe the small-scale structure and microphysical properties of clouds. DuringASTEX, for example, it observed, with 37-m resolution, all marine boundary layer (MBL) stratus and stratocumulus clouds within 5 km of

  18. ARM - Publications: Science Team Meeting Documents

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    Comparison of Stratus Cloud Optical Depths Retrieved from Surface and GOES Measurements over the SGP ARM Central Facility Dong, X., and Smith, W.L. Jr., Analytical Services and Materials, Inc.; Minnis, P., NASA Langley Research Center Eighth Atmospheric Radiation Measurement (ARM) Science Team Meeting For reliable application of satellite datasets in cloud process and single column models, it is important to have a reasonable estimate of the errors in the observed cloud properties. When properly

  19. ARM - Publications: Science Team Meeting Documents

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    The Radiative Properties of Uniform and Broken Stratus: An Observational and Modelling Study Utilizing the Independent Column Approximation for Solar Radiative Transfer Clothiaux, E.E., The Pennsylvania State University; Barker, H.W., Atmospheric Environment Service of Canada; Kato, S., Hampton University; Dong, X., Analytical Service and Materials, Inc. Ackerman, T.P., The Pennsylvania State University; Liljegren, J.C., Ames Laboratory Ninth Atmospheric Radiation Measurement (ARM) Science Team

  20. ARM - Publications: Science Team Meeting Documents

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    An Integrated Algorithm for Retrieving Non-precipitating Stratus Cloud Microphysical Properties Using Millimeter Radar and Microwave Radiometer Data Dong, X. and Mace, G.G., University of Utah Eleventh Atmospheric Radiation Measurement (ARM) Science Team Meeting A new algorithm has been developed to retrieve the vertical profiles of cloud microphysical properties using the ground- based measurements of cloud radar, laser ceilometer, and microwave and solar radiometers. A relationship between

  1. ARM - Publications: Science Team Meeting Documents

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    Arctic Stratus Cloud Properties Deduced from Ground-Based Measurements at the DOE ARM NSA Site Dong, X. and Mace, G.G., University of Utah Eleventh Atmospheric Radiation Measurement (ARM) Science Team Meeting The Arctic plays a major role in global climate change and has considerable influence on the middle latitude belt. The Arctic affects the global climate directly through interactions between its atmosphere, ice cover, land surface and ocean, and through complex coupled feedbacks. To provide

  2. ARM - Publications: Science Team Meeting Documents

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    Microphysical and Radiative Parameters of Stratus Clouds in ARESE II Austin, R.T. (a), Davis, J.M. (a), Miller, S.D. (b), and Stephens, G.L. (a), Colorado State University, Fort Collins (a), Naval Research Laboratory, Monterey, California (b) Eleventh Atmospheric Radiation Measurement (ARM) Science Team Meeting Measurements by airborne cloud radar and passive instruments such as the CSU Scanning Spectral Polarimeter (SSP) during the recent ARESE II field campaign at the Southern Great Plains

  3. ARM - Publications: Science Team Meeting Documents

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    An Integrated Algorithm for Retrieving Low-Level Stratus Cloud Microphysical Properties Using Millimeter Radar and Microwave Radiometer Data Dong, X. and Mace, G.G., University of Utah Twelfth Atmospheric Radiation Measurement (ARM) Science Team Meeting Two methods have been developed for inferring the vertical profiles of cloud microphysics in liquid phase stratocumulus clouds. The first method uses cloud liquid water path derived from microwave radiometer observations and a profile of radar

  4. ARM - Publications: Science Team Meeting Documents

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    Relative Importance of Size Distribution and Liquid Water Path to Solar Radiation in the Presence of Continental Stratus Sengupta, M.(a), Ackerman, T.P.(a), and Clothiaux, E.E.(b), Pacific Northwest National Laboratory (a), The Pennsylavania State University (b) Twelfth Atmospheric Radiation Measurement (ARM) Science Team Meeting Calculation of downwelling broadband solar flux at the surface in the presence of a boundary layer stratiform cloud requires information about the size distribution of

  5. ARM - Publications: Science Team Meeting Documents

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    Climatology of Stratus Clouds at the SGP: A Radiation Based Study Sengupta, M.(a), Ackerman, T.P.(a), and Clothiaux, E.E.(b), Pacific Northwest National Laboratory (a), The Pennsylvania State University (b) Twelfth Atmospheric Radiation Measurement (ARM) Science Team Meeting The Atmospheric Radiation Measurement (ARM) program is a source of continuous data that can be used for various short-term climatological studies. Using multiple datasets from ARM for the Southern Great Plains (SGP) Central

  6. ARM - Publications: Science Team Meeting Documents

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    Comparison of Observed and Modelled Liquid Water Path for Stratus and Stratocumulus Clouds at the SGP Sengupta,M.(a), Ackerman,T.P.(a), and Clothiaux,E.E.(b), Pacific Northwest National Laboratory (a), The Pennsylvania State University (b) Thirteenth Atmospheric Radiation Measurement (ARM) Science Team Meeting Accurate representation of observations in models is a integral part of improving model accuracy. With the availability of long-term data sets from ARM it is possible to statistical

  7. ARM - VAP Product - mmcrmode01v0011cloth

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    11cloth Documentation Data Management Facility Plots (Quick Looks) Citation DOI: 10.5439/1027297 [ What is this? ] Generate Citation 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 VAP Output : MMCRMODE01V0011CLOTH ARSCL: derived, MMCR Mode 1 (stratus mode) moments (11/96 -12/96) Active Dates 1996.11.08 - 1997.03.28

  8. ARM - VAP Product - mmcrmode01v0021cloth

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    21cloth Documentation Data Management Facility Plots (Quick Looks) Citation DOI: 10.5439/1027298 [ What is this? ] Generate Citation 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 VAP Output : MMCRMODE01V0021CLOTH ARSCL: derived, MMCR Mode 1 (stratus mode) moments (2/97) Active Dates 1997.02.26 - 1997.02.26

  9. ARM - VAP Product - mmcrmode01v0031cloth

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    31cloth Documentation Data Management Facility Plots (Quick Looks) Citation DOI: 10.5439/1027300 [ What is this? ] Generate Citation 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 VAP Output : MMCRMODE01V0031CLOTH ARSCL: derived, MMCR Mode 1 (stratus mode) moments (3/97) Active Dates 1997.03.29 - 1997.03.31

  10. ARM - VAP Product - mmcrmode01v0061cloth

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    61cloth Documentation Data Management Facility Plots (Quick Looks) Citation DOI: 10.5439/1027303 [ What is this? ] Generate Citation 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 VAP Output : MMCRMODE01V0061CLOTH ARSCL: derived, MMCR Mode 1 (stratus mode) moments (9/97-3/04) Active Dates 1997.09.15 - 2004.03.17 Originating VAP Process MMCR mode moments, derived by ARSCL process : MMCRMODE Measurements The

  11. ARM - VAP Product - mmcrmode01v0071cloth

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    71cloth Documentation Data Management Facility Plots (Quick Looks) Citation DOI: 10.5439/1027304 [ What is this? ] Generate Citation 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 VAP Output : MMCRMODE01V0071CLOTH ARSCL: derived, MMCR Mode 1 (stratus mode) moments (11/98-9/02) Active Dates 1998.11.01 - 2002.09.21 Originating VAP Process MMCR mode moments, derived by ARSCL process : MMCRMODE Measurements The

  12. ARM - VAP Product - mmcrmode01v0091cloth

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    91cloth Documentation Data Management Facility Plots (Quick Looks) Citation DOI: 10.5439/1027305 [ What is this? ] Generate Citation 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 VAP Output : MMCRMODE01V0091CLOTH ARSCL: derived, MMCR Mode 1 (stratus mode) moments (3/98-4/04) Active Dates 1998.03.25 - 2004.04.13 Originating VAP Process MMCR mode moments, derived by ARSCL process : MMCRMODE Measurements The

  13. Microsoft PowerPoint - ARMST2007_mp.ppt

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    in Arctic Mixed-Phase Stratus Matthew D. Shupe a , Pavlos Kollias b , Ola Persson a , Ed Luke b Greg McFarquhar c , Michael Poellot d , Edwin Eloranta e a CIRES - University of Colorado and NOAA/ESRL/PSD, b Brookhaven National Laboratory, c University of Illinois, d University of North Dakota, e University of Wisonsin Mixed-Phase Cloud Properties Air Motions from Doppler Spectra Funded by: ARM Grant DE-FG02-05ER63965 Summary A Conceptual Model relating air motions and microphysics A Doppler

  14. Research Highlights Sorted by Submitter

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    Submitter A B C D E F G H I J K L M N O P Q R S T U V W X Y Z A Ackerman, A. Buffering of Ice Crystal Number Concentration to Ice Nucleus Abundance above Arctic Stratus ARM To Be or Not To Be Liquid? The Challenge of Arctic Mixed-Phase Cloud Modeling ARM Tropical Rain Clouds Still a Challenge to Cloud-Resolving Models ARM ASR Understanding Ice Formation in Arctic Mixed-Phase Boundary-Layer Clouds During ISDAC ARM Ackerman, T. P. Progress in Understanding Water Vapor's Role in Models ARM

  15. Research Highlight

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    Validation of CERES-MODIS Cloud Properties Using ARM Data Submitter: Dong, X., University of Arizona Area of Research: Cloud Distributions/Characterizations Working Group(s): Cloud Properties Journal Reference: Dong, X., P. Minnis, B. Xi, S. Sun-Mack, and Y. Chen, 2007: Validation of CERES-MODIS stratus cloud properties using ground-based measurements at the DOE ARM SGP site. Accepted by J. Geophys. Res. Wielicki, B. A. and Co-authors (2000), CERES Validation Plan Overview, Release 4, 10/20/00,

  16. Impact of aerosol on mixed-phase stratocumulus during MPACE in a mesoscale

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    model with two-moment microphysics Impact of aerosol on mixed-phase stratocumulus during MPACE in a mesoscale model with two-moment microphysics Morrison, Hugh MMM/ASP National Center for Atmospheric Research Pinto, James University of Colorado Curry, Judith Georgia Institute of Technology Category: Modeling The Penn State/NCAR mesoscale model MM5 is coupled to a new microphysics scheme to examine the impact of aerosol on mixed-phase stratocumulus during the Mixed-Phase Arctic Stratus

  17. ARM - Publications: Science Team Meeting Documents

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    A Comparison of Surface Sensible Heat Flux at Atqasuk and Barrow Shaw, W.J. (a), Doran, J.C. (b), and Hubbe, J.M. (c), Pacific Northwest National Laboratory Eleventh Atmospheric Radiation Measurement (ARM) Science Team Meeting As part of the effort to discover the feedbacks between low-level arctic stratus and surface fluxes, we have operated an acoustic anemometer near Barrow, Alaska and a dual wavelength scintillometer near Atqasuk, which is 100 km to the south, in order to measure the surface

  18. ARM - Publications: Science Team Meeting Documents

    U.S. Department of Energy (DOE) - all webpages (Extended Search)

    Variability of Low Stratus Over the ARM SGP CART Based on Cloud Radar Data and LES Simulations Kogan, Z.N., Mechem, D.B., and Kogan, Y.L., Cooperative Institute for Mesoscale Meteorological Studies/University of Oklahoma Twelfth Atmospheric Radiation Measurement (ARM) Science Team Meeting The accurate formulation of cloud physics processes in large-scale models is complicated by the inability to characterize the spatial variability of cloud fields on a sub-grid scale. We present the results of

  19. Final technical Report DE-FG02-06ER65187

    SciTech Connect

    Edwin Eloranta

    2009-07-17

    Simulations from the University of Wisconsin Non-Hydrostatic Modeling System (UW-NMS) along with those from other models indicate a strong tendency to overproduce ice, resulting in a decimation of the liquid portion of mixed-phase stratus through the Bergeron-Findeissen process. Immersion freezing was illustrated to be a major contributor to ice production within these cloud layers, and aerosol properties were illustrated to be an important consideration in the simulation of this process. In particular, the soluble mass fraction and aerosol insoluble mass type were demonstrated to influence simulation of the immersion freezing process, Data collected by the Arctic High Spectral Resolution Lidar and Millimeter Cloud Radar during the M-PACE period was analyzed in order to provide a statistical dataset for validation of simulations of mixed-phase stratus. 270 hours of single-layer cases were reviewed, and mean values for cloud base height, cloud thickness, cloud optical thickness, cloud temperature, wind direction, and liquid and ice particle size, particle number density, and water content were derived.

  20. Absorption of solar radiation in broken clouds

    SciTech Connect

    Zuev, V.E.; Titov, G.A.; Zhuravleva, T.B.

    1996-04-01

    It is recognized now that the plane-parallel model unsatisfactorily describes the transfer of radiation through broken clouds and that, consequently, the radiation codes of general circulation models (GCMs) must be refined. However, before any refinement in a GCM code is made, it is necessary to investigate the dependence of radiative characteristics on the effects caused by the random geometry of cloud fields. Such studies for mean fluxes of downwelling and upwelling solar radiation in the visible and near-infrared (IR) spectral range were performed by Zuev et al. In this work, we investigate the mean spectral and integrated absorption of solar radiation by broken clouds (in what follows, the term {open_quotes}mean{close_quotes} will be implied but not used, for convenience). To evaluate the potential effect of stochastic geometry, we will compare the absorption by cumulus (0.5 {le} {gamma} {le} 2) to that by equivalent stratus ({gamma} <<1) clouds; here {gamma} = H/D, H is the cloud layer thickness and D the characteristic horizontal cloud size. The equivalent stratus clouds differ from cumulus only in the aspect ratio {gamma}, all the other parameters coinciding.

  1. A boundary-layer cloud study using Southern Great Plains Cloud and radiation testbed (CART) data

    SciTech Connect

    Albrecht, B.; Mace, G.; Dong, X.; Syrett, W.

    1996-04-01

    Boundary layer clouds-stratus and fairweather cumulus - are closely coupled involves the radiative impact of the clouds on the surface energy budget and the strong dependence of cloud formation and maintenance on the turbulent fluxes of heat and moisture in the boundary layer. The continuous data collection at the Southern Great Plains (SGP) Cloud and Radiation Testbed (CART) site provides a unique opportunity to study components of the coupling processes associated with boundary layer clouds and to provide descriptions of cloud and boundary layer structure that can be used to test parameterizations used in climate models. But before the CART data can be used for process studies and parameterization testing, it is necessary to evaluate and validate data and to develop techniques for effectively combining the data to provide meaningful descriptions of cloud and boundary layer characteristics. In this study we use measurements made during an intensive observing period we consider a case where low-level stratus were observed at the site for about 18 hours. This case is being used to examine the temporal evolution of cloud base, cloud top, cloud liquid water content, surface radiative fluxes, and boundary layer structure. A method for inferring cloud microphysics from these parameters is currently being evaluated.

  2. Summertime Low-Level Jets over the Great Plains

    SciTech Connect

    Stensrud, D.J.

    1996-04-01

    The sky over the southern Great Plains Cloud and Atmospheric Radiation Testbed (CART) site of the Atmospheric Radiation Measurement (ARM) Program during the predawn and early morning hours often is partially obstructed by stratocumulus, stratus fractus, or cumulus fractus that are moving rapidly to the north, even through the surface winds are weak. This cloud movement is evidence of the low-level jet (LLJ), a wind speed maximum that occurs in the lowest few kilometers of the atmosphere. Owing to the wide spacing between upper-air sounding sites and the relatively infrequent sounding launches, LLJ evolution has been difficult to observe adequately, even though the effects of LLJs on moisture flux into North America are large. Model simulation of the LLJ is described.

  3. Coupling Between Oceanic Upwelling and Cloud-aerosol Properties at the AMF Point Reyes Site

    SciTech Connect

    Dunn, M.; Jensen, M.; Miller, M.; Kollias, P.; Bartholomew, M. J.; Turner, D.; Andrews, E.; Jefferson, A.; Daum, P.

    2008-03-10

    Cloud microphysical properties measured at the ARM Mobile Facility site located on the northern coast of California near Point Reyes, during the 2005 Marine Stratus Radiation, Aerosol and Drizzle experiment, were analyzed to determine their relationship to the coastal sea surface temperature (SST) which was characterized using measurements acquired from a National Oceanic and Atmospheric Administration offshore buoy. An increase in SST resulting from a relaxation of upwelling, occurring in the eastern Pacific Ocean off the coast of California in summer is observed to strongly correlate with nearby ground measured cloud microphysical properties and cloud condensation nuclei (CCN) concentrations. Correlations between these atmospheric and oceanic features provide insight into the interplay between the ocean and cloud radiative properties. We present evidence of this robust correlation and examine the factors controlling these features. The marine boundary layer is in direct contact with the sea surface and is strongly influenced by SST. Moisture and vertical motion are crucial ingredients for cloud development and so we examine the role of SST in providing these key components to the atmosphere. Although upwelling of cold subsurface waters is conventionally thought to increase aerosols in the region, thus increasing clouds, here we observed a relaxation of upwelling associated with changes in the structure of marine stratus clouds. As upwelling relaxes, the SST get warmer, thick clouds with high liquid water paths are observed and persist for a few days. This cycle is repeated throughout the summer upwelling season. A concomitant cyclic increase and decrease of CCN concentration is also observed. Forcing mechanisms and large-scale atmospheric features are discussed. Marine stratocumulus clouds are a critical component of the earth's radiation budget and this site provides an excellent opportunity to study the influence of SST on these clouds.

  4. Boundary Layer Cloudiness Parameterizations Using ARM Observations

    SciTech Connect

    Bruce Albrecht

    2004-09-15

    This study used DOE ARM data and facilities to: (1) study macroscopic properties of continental stratus clouds at SGP and the factors controlling these properties, (2) develop a scientific basis for understanding the processes responsible for the formation of boundary layer clouds using ARM observations in conjunction with simple parametric models and LES, and (3) evaluate cumulus cloud characteristics retrieved from the MMCR operating at TWP-Nauru. In addition we have used high resolution 94 GHz observations of boundary layer clouds and precipitation to: (1) develop techniques for using high temporal resolution Doppler velocities to study large-eddy circulations and turbulence in boundary layer clouds and estimate the limitations of using current and past MMCR data for boundary layer cloud studies, (2) evaluate the capability and limitations of the current MMCR data for estimating reflectivity, vertical velocities, and spectral under low- signal-to-noise conditions associated with weak no n-precipitating clouds, (3) develop possible sampling modes for the new MMCR processors to allow for adequate sampling of boundary layer clouds, and (4) retrieve updraft and downdraft structures under precipitating conditions.

  5. Final Technical Report ARM DOE Grant #DE-FG02-03ER63520 Parameterizations of Shortwave Radiactive Properties of Broken Clouds from Satellite and Ground-Based Measurements

    SciTech Connect

    Albrecht, Bruce, A.

    2006-06-19

    This study used DOE ARM data and facilities to: 1) study macroscopic properties of continental stratus clouds at SGP and the factors controlling these properties, 2) develop a scientific basis for understanding the pocesses responsible for the formation of boundary layer clouds using ARM observations in conjunction with simple parametric models and LES, and 3) evaluate cumulus cloud characteristics retrieved retrieved from the MMCR operating at TWP-Nauru. In addition we have used high resolution 94 GHz observations of boundary layer clouds and precipitation to: 1)develop techniques for using high temporal resolution Doppler velocities to study large-eddy circulations and turbulence in boundary layer clouds and estimate the limitations of using current and past MMCR data for boundary layer cloud studies, 2) evaluate the capability and limitation of the current MMCR data for estimating reflectivity, vertical velocities, and spectral under low-signal-to-noise conditions associated with weak non-precipitating clouds, 3) develop possible sampling modes for the new MMCR processors to allow for adequate sampling of boundary layer clouds, and 4) retrieve updraft and downdraft structures under precipitating conditions.

  6. Satellite estimates of precipitation susceptibility in low-level marine stratiform clouds

    DOE PAGES [OSTI]

    Terai, C. R.; Wood, R.; Kubar, T. L.

    2015-09-05

    Quantifying the sensitivity of warm rain to aerosols is important for constraining climate model estimates of aerosol indirect effects. In this study, the precipitation sensitivity to cloud droplet number concentration (Nd) in satellite retrievals is quantified by applying the precipitation susceptibility metric to a combined CloudSat/Moderate Resolution Imaging Spectroradiometer data set of stratus and stratocumulus clouds that cover the tropical and subtropical Pacific Ocean and Gulf of Mexico. We note that consistent with previous observational studies of marine stratocumulus, precipitation susceptibility decreases with increasing liquid water path (LWP), and the susceptibility of the mean precipitation rate R is nearly equalmore » to the sum of the susceptibilities of precipitation intensity and of probability of precipitation. Consistent with previous modeling studies, the satellite retrievals reveal that precipitation susceptibility varies not only with LWP but also with Nd. Puzzlingly, negative values of precipitation susceptibility are found at low LWP and high Nd. There is marked regional variation in precipitation susceptibility values that cannot simply be explained by regional variations in LWP and Nd. This suggests other controls on precipitation apart from LWP and Nd and that precipitation susceptibility will need to be quantified and understood at the regional scale when relating to its role in controlling possible aerosol-induced cloud lifetime effects.« less

  7. Satellite estimates of precipitation susceptibility in low-level marine stratiform clouds

    SciTech Connect

    Terai, C. R.; Wood, R.; Kubar, T. L.

    2015-09-05

    Quantifying the sensitivity of warm rain to aerosols is important for constraining climate model estimates of aerosol indirect effects. In this study, the precipitation sensitivity to cloud droplet number concentration (Nd) in satellite retrievals is quantified by applying the precipitation susceptibility metric to a combined CloudSat/Moderate Resolution Imaging Spectroradiometer data set of stratus and stratocumulus clouds that cover the tropical and subtropical Pacific Ocean and Gulf of Mexico. We note that consistent with previous observational studies of marine stratocumulus, precipitation susceptibility decreases with increasing liquid water path (LWP), and the susceptibility of the mean precipitation rate R is nearly equal to the sum of the susceptibilities of precipitation intensity and of probability of precipitation. Consistent with previous modeling studies, the satellite retrievals reveal that precipitation susceptibility varies not only with LWP but also with Nd. Puzzlingly, negative values of precipitation susceptibility are found at low LWP and high Nd. There is marked regional variation in precipitation susceptibility values that cannot simply be explained by regional variations in LWP and Nd. This suggests other controls on precipitation apart from LWP and Nd and that precipitation susceptibility will need to be quantified and understood at the regional scale when relating to its role in controlling possible aerosol-induced cloud lifetime effects.

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

    SciTech Connect

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

    2012-09-28

    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

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

    SciTech Connect

    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

    2011-02-01

    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.

  10. Efficacy of Aerosol-Cloud Interactions Under Varying Meteorological Conditions: Southern Great Plains Vs. Pt. Reyes

    SciTech Connect

    Dunn, M.; Schwartz, S.; Kim, B.-G.; Miller, M.; Liu, Y.; Min, Q.

    2008-03-10

    Several studies have demonstrated that cloud dynamical processes such as entrainment mixing may be the primary modulator of cloud optical properties in certain situations. For example, entrainment of dry air alters the cloud drop size distribution by enhancing drop evaporation. However, the effect of entrainment mixing and other forms or turbulence is still quite uncertain. Although these factors and aerosol-cloud interactions should be considered together when evaluating the efficacy of aerosol indirect effects, the underlying mechanisms appear to be dependent upon each other. In addition, accounting for them is impossible with the current understanding of aerosol indirect effect. Therefore, careful objective screening and analysis of observations are needed to determine the extent to which mixing related properties affect cloud optical properties, apart from the aerosol first indirect effect. This study addresses the role of aerosol-cloud interactions in the context of varying meteorological conditions based on ARM data obtained at the Southern Great Plains (SGP) site in Oklahoma and at Pt. Reyes, California. Previous analyses of the continental stratiform clouds at the SGP site have shown that the thicker clouds of high liquid water path (LWP) tend to contain sub adiabatic LWPs. These sub adiabatic LWPs, which result from active mixing processes, correspond to a lower susceptibility of the clouds to aerosol-cloud interactions, and, hence, to reduced aerosol indirect effects. In contrast, the consistently steady and thin maritime stratus clouds observed at Pt. Reyes are much closer to adiabatic. These clouds provide an excellent benchmark for the study of the aerosol influence on modified marine clouds relative to continental clouds, since they form in a much more homogeneous meteorological environment than those at the continental site.

  11. Modeling the summertime Arctic cloudy boundary layer

    SciTech Connect

    Curry, J.A.; Pinto, J.O.; McInnes, K.L.

    1996-04-01

    Global climate models have particular difficulty in simulating the low-level clouds during the Arctic summer. Model problems are exacerbated in the polar regions by the complicated vertical structure of the Arctic boundary layer. The presence of multiple cloud layers, a humidity inversion above cloud top, and vertical fluxes in the cloud that are decoupled from the surface fluxes, identified in Curry et al. (1988), suggest that models containing sophisticated physical parameterizations would be required to accurately model this region. Accurate modeling of the vertical structure of multiple cloud layers in climate models is important for determination of the surface radiative fluxes. This study focuses on the problem of modeling the layered structure of the Arctic summertime boundary-layer clouds and in particular, the representation of the more complex boundary layer type consisting of a stable foggy surface layer surmounted by a cloud-topped mixed layer. A hierarchical modeling/diagnosis approach is used. A case study from the summertime Arctic Stratus Experiment is examined. A high-resolution, one-dimensional model of turbulence and radiation is tested against the observations and is then used in sensitivity studies to infer the optimal conditions for maintaining two separate layers in the Arctic summertime boundary layer. A three-dimensional mesoscale atmospheric model is then used to simulate the interaction of this cloud deck with the large-scale atmospheric dynamics. An assessment of the improvements needed to the parameterizations of the boundary layer, cloud microphysics, and radiation in the 3-D model is made.

  12. Contribution to the development of DOE ARM Climate Modeling Best Estimate Data (CMBE) products: Satellite data over the ARM permanent and AMF sites: Final Report

    SciTech Connect

    Xie, B; Dong, X; Xie, S

    2012-05-18

    To support the LLNL ARM infrastructure team Climate Modeling Best Estimate (CMBE) data development, the University of North Dakota (UND)'s group will provide the LLNL team the NASA CERES and ISCCP satellite retrieved cloud and radiative properties for the periods when they are available over the ARM permanent research sites. The current available datasets, to date, are as follows: the CERES/TERRA during 200003-200812; the CERES/AQUA during 200207-200712; and the ISCCP during 199601-200806. The detailed parameters list below: (1) CERES Shortwave radiative fluxes (net and downwelling); (2) CERES Longwave radiative fluxes (upwelling) - (items 1 & 2 include both all-sky and clear-sky fluxes); (3) CERES Layered clouds (total, high, middle, and low); (4) CERES Cloud thickness; (5) CERES Effective cloud height; (6) CERES cloud microphysical/optical properties; (7) ISCCP optical depth cloud top pressure matrix; (8) ISCCP derived cloud types (r.g., cirrus, stratus, etc.); and (9) ISCCP infrared derived cloud top pressures. (10) The UND group shall apply necessary quality checks to the original CERES and ISCCP data to remove suspicious data points. The temporal resolution for CERES data should be all available satellite overpasses over the ARM sites; for ISCCP data, it should be 3-hourly. The spatial resolution is the closest satellite field of view observations to the ARM surface sites. All the provided satellite data should be in a format that is consistent with the current ARM CMBE dataset so that the satellite data can be easily merged into the CMBE dataset.

  13. Determining Best Estimates and Uncertainties in Cloud Microphysical Parameters from ARM Field Data: Implications for Models, Retrieval Schemes and Aerosol-Cloud-Radiation Interactions

    SciTech Connect

    McFarquhar, Greg

    2015-12-28

    We proposed to analyze in-situ cloud data collected during ARM/ASR field campaigns to create databases of cloud microphysical properties and their uncertainties as needed for the development of improved cloud parameterizations for models and remote sensing retrievals, and for evaluation of model simulations and retrievals. In particular, we proposed to analyze data collected over the Southern Great Plains (SGP) during the Mid-latitude Continental Convective Clouds Experiment (MC3E), the Storm Peak Laboratory Cloud Property Validation Experiment (STORMVEX), the Small Particles in Cirrus (SPARTICUS) Experiment and the Routine AAF Clouds with Low Optical Water Depths (CLOWD) Optical Radiative Observations (RACORO) field campaign, over the North Slope of Alaska during the Indirect and Semi-Direct Aerosol Campaign (ISDAC) and the Mixed-Phase Arctic Cloud Experiment (M-PACE), and over the Tropical Western Pacific (TWP) during The Tropical Warm Pool International Cloud Experiment (TWP-ICE), to meet the following 3 objectives; derive statistical databases of single ice particle properties (aspect ratio AR, dominant habit, mass, projected area) and distributions of ice crystals (size distributions SDs, mass-dimension m-D, area-dimension A-D relations, mass-weighted fall speeds, single-scattering properties, total concentrations N, ice mass contents IWC), complete with uncertainty estimates; assess processes by which aerosols modulate cloud properties in arctic stratus and mid-latitude cumuli, and quantify aerosol’s influence in context of varying meteorological and surface conditions; and determine how ice cloud microphysical, single-scattering and fall-out properties and contributions of small ice crystals to such properties vary according to location, environment, surface, meteorological and aerosol conditions, and develop parameterizations of such effects.In this report we describe the accomplishments that we made on all 3 research objectives.

  14. Pacific Northwest Laboratory annual report for 1994 to the DOE Office of Energy Research. Part 2: Atmospheric and climate research

    SciTech Connect

    1995-04-01

    Atmospheric research at Pacific Northwest Laboratory (PNL) occurs in conjunction with the Atmospheric Chemistry Program (ACP) and with the Atmospheric Studies in Complex Terrain (ASCOT) Program. Solicitations for proposals and peer review were used to select research projects for funding in FY 1995. Nearly all ongoing projects were brought to a close in FY 1994. Therefore, the articles in this volume include a summary of the long-term accomplishments as well as the FY 1994 progress made on these projects. The following articles present summaries of the progress in FY 1994 under these research tasks: continental and oceanic fate of pollutants; research aircraft operations; ASCOT program management; coupling/decoupling of synoptic and valley circulations; interactions between surface exchange processes and atmospheric circulations; and direct simulations of atmospheric turbulence. Climate change research at PNL is aimed at reducing uncertainties in the fundamental processes that control climate systems that currently prevent accurate predictions of climate change and its effects. PNL is responsible for coordinating and integrating the field and laboratory measurement programs, modeling studies, and data analysis activities of the Atmospheric Radiation Measurements (ARM) program. In FY 1994, PNL scientists conducted 3 research projects under the ARM program. In the first project, the sensitivity of GCM grid-ad meteorological properties to subgrid-scale variations in surface fluxes and subgrid-scale circulation patterns is being tested in a single column model. In the second project, a new and computationally efficient scheme has been developed for parameterizing stratus cloud microphysics in general circulation models. In the last project, a balloon-borne instrument package is being developed for making research-quality measurements of radiative flux divergence profiles in the lowest 1,500 meters of the Earth`s atmosphere.

  15. Analyzing signatures of aerosol-cloud interactions from satelliteretrievals and the GISS GCM to constrain the aerosol indirecteffect

    SciTech Connect

    Menon, S.; Del Genio, A.D.; Kaufman, Y.; Bennartz, R.; Koch, D.; Loeb, N.; Orlikowski, D.

    2007-10-01

    Evidence of aerosol-cloud interactions are evaluated using satellite data from MODIS, CERES, AMSR-E, reanalysis data from NCEP and data from the NASA Goddard Institute for Space Studies climate model. We evaluate a series of model simulations: (1) Exp N- aerosol direct radiative effects; (2) Exp C- Like Exp N but with aerosol effects on liquid-phase cumulus and stratus clouds; (3) Exp CN- Like Exp C but with model wind fields nudged to reanalysis data. Comparison between satellite-retrieved data and model simulations for June to August 2002, over the Atlantic Ocean indicate the following: a negative correlation between aerosol optical thickness (AOT) and cloud droplet effective radius (R{sub eff}) for all cases and satellite data, except for Exp N; a weak but negative correlation between liquid water path (LWP) and AOT for MODIS and CERES; and a robust increase in cloud cover with AOT for both MODIS and CERES. In all simulations, there is a positive correlation between AOT and both cloud cover and LWP (except in the case of LWP-AOT for Exp CN). The largest slopes are obtained for Exp N, implying that meteorological variability may be an important factor. The main fields associated with AOT variability in NCEP/MODIS data are warmer temperatures and increased subsidence for less clean cases, not well captured by the model. Simulated cloud fields compared with an enhanced data product from MODIS and AMSR-E indicate that model cloud thickness is over-predicted and cloud droplet number is within retrieval uncertainties. Since LWP fields are comparable this implies an under-prediction of R{sub eff} and thus an over-prediction of the indirect effect.

  16. NCAR Contribution to A U.S. National Multi-Model Ensemble (NMME) ISI Prediction System

    SciTech Connect

    Tribbia, Joseph

    2015-11-25

    NCAR brought the latest version of the Community Earth System Model (version 1, CESM1) into the mix of models in the NMME effort. This new version uses our newest atmospheric model CAM5 and produces a coupled climate and ENSO that are generally as good or better than those of the Community Climate System Model version 4 (CCSM4). Compared to CCSM4, the new coupled model has a superior climate response with respect to low clouds in both the subtropical stratus regimes and the Arctic. However, CESM1 has been run to date using a prognostic aerosol model that more than doubles its computational cost. We are currently evaluating a version of the new model using prescribed aerosols and expect it will be ready for integrations in summer 2012. Because of this NCAR has not been able to complete the hindcast integrations using the NCAR loosely-coupled ensemble Kalman filter assimilation method nor has it contributed to the current (Stage I) NMME operational utilization. The expectation is that this model will be included in the NMME in late 2012 or early 2013. The initialization method will utilize the Ensemble Kalman Filter Assimilation methods developed at NCAR using the Data Assimilation Research Testbed (DART) in conjunction with Jeff Anderson’s team in CISL. This methodology has been used in our decadal prediction contributions to CMIP5. During the course of this project, NCAR has setup and performed all the needed hindcast and forecast simulations and provide the requested fields to our collaborators. In addition, NCAR researchers have participated fully in research themes (i) and (ii). Specifically, i) we have begun to evaluate and optimize our system in hindcast mode, focusing on the optimal number of ensemble members, methodologies to recalibrate individual dynamical models, and accessing our forecasts across multiple time scales, i.e., beyond two weeks, and ii) we have begun investigation of the role of different ocean initial conditions in seasonal forecasts. The

  17. Chemical Composition and Sources of Coastal Marine Aerosol Particles during the 2008 VOCALS-REx Campaign

    SciTech Connect

    Lee, Y.- N.; Springston, S.; Jayne, John T.; Wang, Jian; Hubbe, John M.; Senum, Gunnar I.; Kleinman, Lawrence I.; Daum, Peter H.

    2014-05-23

    The chemical composition of aerosol particles (Dp 1.5 ?m) was measured over the southeast Pacific Ocean during the VAMOS (Variability of the American Monsoon Systems) Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-Rex) between 16 October and 15 November 2008 using the US Department of Energy (DOE) G-1 aircraft. The objective of these flights was to gain an understanding of the sources and evolution of these aerosols, and of how they interact with the marine stratus cloud layer that prevails in this region of the globe. Our measurements showed that the marine boundary layer (MBL) aerosol mass was dominated by non-sea-salt SO2?4, followed by Na+, Cl?, Org (total organics), NH+4 , and NO?3 , in decreasing order of importance; CH3SO?3 (MSA), Ca2+, and K+ rarely exceeded their limits of detection. Aerosols were strongly acidic with a NH+4 to SO2?4 equivalents ratio typically < 0.3. Sea-salt aerosol (SSA) particles, represented by NaCl, exhibited Cl? deficits caused by both HNO3 and H2SO4, but for the most part were externally mixed with particles, mainly SO2?4. SSA contributed only a small fraction of the total accumulation mode particle number concentration. It was inferred that all aerosol species (except SSA) were of predominantly continental origin because of their strong land-to-sea concentration gradient. Comparison of relative changes in median values suggests that (1) an oceanic source of NH3 is present between 72 W and 76 W, (2) additional organic aerosols from biomass burns or biogenic precursors were emitted from coastal regions south of 31 S, with possible cloud processing, and (3) free tropospheric (FT) contributions to MBL gas and aerosol concentrations were negligible. The very low levels of CH3SO?3 observed as well as the correlation between SO2?4 and NO?3 (which is thought primarily anthropogenic) suggest a limited contribution of DMS to SO2?4 aerosol production during VOCALS.

  18. A Seasonal Perspective on Regional Air Quality in CentralCalifornia - Phase 1

    SciTech Connect

    Harley, Robert A.; Brown, Nancy J.; Tonse, Shaheen R.; Jin, Ling

    2006-12-01

    concentrations for O{sub 3}, NO{sub x}, NO{sub y}, and CO at about 100 ground observation stations within the CCOS domain. Comparisons were made both for time series and for statistically aggregated metrics, to assess model performance over the whole modeling domain and for the individual air basins within the domain. The model tends to over-predict ozone levels along the coast where observed levels are generally low. Inland performance in the San Joaquin Valley is generally better. Model-measurement agreement for night-time ozone is improved by evaluating the sum of predicted O{sub 3} + NO{sub 2} against observations; this removes from the comparison the effect of any ozone titration that may occur. A variety of diagnostic simulations were conducted to investigate the causes for differences between predictions and observations. These included (1) enhanced deposition of O{sub 3} to the ocean, (2) reduced vertical mixing over the ocean, (3) attenuation of sunlight by coastal stratus, (4) the influence of surface albedo on photochemistry, and (5) the effects of observation nudging on wind fields. Use of advanced model probing tools such as process analysis and sensitivity analysis is demonstrated by diagnosing model sensitivity to boundary conditions and to weekday-weekend emission changes.

  19. The Radiative Role of Free Tropospheric Aerosols and Marine Clouds over the Central North Atlantic

    SciTech Connect

    Mazzoleni, Claudio; Kumar, Sumit; Wright, Kendra; Kramer, Louisa; Mazzoleni, Lynn; Owen, Robert; Helmig, Detlev

    2014-12-09

    microscope – were often very compacted, suggesting cloud processing and exhibiting different optical properties from fresh emissions. In addition, black carbon was found to be sometimes mixed with mineral dust, affecting its optical properties and potential forcing. c) Some aerosols collected at PMO acted as ice nuclei, potentially contributing to cirrus cloud formation during their transport in the upper free troposphere. Identified good ice nuclei were often mineral dust particles. d) The free tropospheric aerosols studied at PMO have relevance to low level marine clouds due, for example, to synoptic subsidence entraining free tropospheric aerosols into the marine boundary layer. This has potentially large consequences on cloud condensation nuclei concentrations and compositions in the marine boundary layer; therefore, having an effect on the marine stratus clouds, with potentially important repercussions on the radiative forcing. The scientific products of this project currently include contributions to two papers published in the Nature Publishing group (Nature Communications and Scientific Reports), one paper under revision for Atmospheric Chemistry and Physics, one in review in Geophysical Research Letters and one recently submitted to Atmospheric Chemistry and Physics Discussion. In addition, four manuscripts are in advanced state of preparation. Finally, twenty-eight presentations were given at international conferences, workshops and seminars.

  20. Use of ARM Products in Reanalysis Applications and IPCC Model Assessment

    SciTech Connect

    Walsh, John E; Chapman, William L

    2011-09-30

    generally lower sea level pressures near the North Slope and onshore flow from the NW in most months. Warm season errors were highest when high pressure was persistent to the north of Barrow, AK. This synoptic situation results in onshore flow for the North Slope with persistent winds from the east and northeast. In these situations, the predominant climatological synoptic situation, the NARR model under-simulates summer clouds on the North Slope. In general, the NARR often fails to capture clouds in the lowest 200 meters of the atmosphere. We conclude that the cloud model parameterization fails to cature boundary layer clouds like Arctic stratus and fog, which are observed in 65% of the undersimulations. These NARR undersimulations occur most often during onshore flow environments, such as when high pressure is located north of Barrow and the prevailing winds are from the northeast. In these cases, the airflow is along a fetch of scattered sea ice and open ocean (ice concentrations between 0 and 100%). NARR treats sea ice as a binary function. Grid cells are either considered a slap of ice cover, or totally open ocean. We note that implementing provisions for partial sea ice concentrations in the reanalysis model may help in more accurately depicting surface moisture fluxes and associated model-derived low cloud amounts.

  1. Computing for Finance

    ScienceCinema

    None

    2011-10-06

    with UBS for the past 9 years. During his tenure at UBS, he has had a number of leadership roles within IT in development, support and architecture. In 2006 Michael relocated to Switzerland to take up his current role as head of the UBS IB Technical Council, responsible for the overall technology strategy and vision of the Investment Bank. One of Michael's key responsibilities is to manage the UBS High Performance Computing Research Lab and he has been involved in a number of initiatives in the HPC space. 2. Grid in the Commercial WorldFred Gedling, Chief Technology Officer EMEA and Senior Vice President Global Services, DataSynapse Grid computing gets mentions in the press for community programs starting last decade with "Seti@Home". Government, national and supranational initiatives in grid receive some press. One of the IT-industries' best-kept secrets is the use of grid computing by commercial organizations with spectacular results. Grid Computing and its evolution into Application Virtualization is discussed and how this is key to the next generation data center. Speaker Bio: Fred Gedling holds the joint roles of Chief Technology Officer for EMEA and Senior Vice President of Global Services at DataSynapse, a global provider of application virtualisation software. Based in London and working closely with organisations seeking to optimise their IT infrastructures, Fred offers unique insights into the technology of virtualisation as well as the methodology of establishing ROI and rapid deployment to the immediate advantage of the business. Fred has more than fifteen years experience of enterprise middleware and high-performance infrastructures. Prior to DataSynapse he worked in high performance CRM middleware and was the CTO EMEA for New Era of Networks (NEON) during the rapid growth of Enterprise Application Integration. His 25-year career in technology also includes management positions at Goldman Sachs and Stratus Computer. Fred holds a First Class Bsc (Hons

  2. Computing for Finance

    SciTech Connect

    2010-03-24

    remained with UBS for the past 9 years. During his tenure at UBS, he has had a number of leadership roles within IT in development, support and architecture. In 2006 Michael relocated to Switzerland to take up his current role as head of the UBS IB Technical Council, responsible for the overall technology strategy and vision of the Investment Bank. One of Michael's key responsibilities is to manage the UBS High Performance Computing Research Lab and he has been involved in a number of initiatives in the HPC space. 2. Grid in the Commercial WorldFred Gedling, Chief Technology Officer EMEA and Senior Vice President Global Services, DataSynapse Grid computing gets mentions in the press for community programs starting last decade with "Seti@Home". Government, national and supranational initiatives in grid receive some press. One of the IT-industries' best-kept secrets is the use of grid computing by commercial organizations with spectacular results. Grid Computing and its evolution into Application Virtualization is discussed and how this is key to the next generation data center. Speaker Bio: Fred Gedling holds the joint roles of Chief Technology Officer for EMEA and Senior Vice President of Global Services at DataSynapse, a global provider of application virtualisation software. Based in London and working closely with organisations seeking to optimise their IT infrastructures, Fred offers unique insights into the technology of virtualisation as well as the methodology of establishing ROI and rapid deployment to the immediate advantage of the business. Fred has more than fifteen years experience of enterprise middleware and high-performance infrastructures. Prior to DataSynapse he worked in high performance CRM middleware and was the CTO EMEA for New Era of Networks (NEON) during the rapid growth of Enterprise Application Integration. His 25-year career in technology also includes management positions at Goldman Sachs and Stratus Computer. Fred holds a First Class Bsc (Hons

  3. Computing for Finance

    ScienceCinema

    None

    2016-07-12

    remained with UBS for the past 9 years. During his tenure at UBS, he has had a number of leadership roles within IT in development, support and architecture. In 2006 Michael relocated to Switzerland to take up his current role as head of the UBS IB Technical Council, responsible for the overall technology strategy and vision of the Investment Bank. One of Michael's key responsibilities is to manage the UBS High Performance Computing Research Lab and he has been involved in a number of initiatives in the HPC space. 2. Grid in the Commercial WorldFred Gedling, Chief Technology Officer EMEA and Senior Vice President Global Services, DataSynapse Grid computing gets mentions in the press for community programs starting last decade with "Seti@Home". Government, national and supranational initiatives in grid receive some press. One of the IT-industries' best-kept secrets is the use of grid computing by commercial organizations with spectacular results. Grid Computing and its evolution into Application Virtualization is discussed and how this is key to the next generation data center. Speaker Bio: Fred Gedling holds the joint roles of Chief Technology Officer for EMEA and Senior Vice President of Global Services at DataSynapse, a global provider of application virtualisation software. Based in London and working closely with organisations seeking to optimise their IT infrastructures, Fred offers unique insights into the technology of virtualisation as well as the methodology of establishing ROI and rapid deployment to the immediate advantage of the business. Fred has more than fifteen years experience of enterprise middleware and high-performance infrastructures. Prior to DataSynapse he worked in high performance CRM middleware and was the CTO EMEA for New Era of Networks (NEON) during the rapid growth of Enterprise Application Integration. His 25-year career in technology also includes management positions at Goldman Sachs and Stratus Computer. Fred holds a First Class Bsc (Hons

  4. Computing for Finance

    ScienceCinema

    None

    2011-10-06

    with UBS for the past 9 years. During his tenure at UBS, he has had a number of leadership roles within IT in development, support and architecture. In 2006 Michael relocated to Switzerland to take up his current role as head of the UBS IB Technical Council, responsible for the overall technology strategy and vision of the Investment Bank. One of Michael's key responsibilities is to manage the UBS High Performance Computing Research Lab and he has been involved in a number of initiatives in the HPC space. 2. Grid in the Commercial WorldFred Gedling, Chief Technology Officer EMEA and Senior Vice President Global Services, DataSynapse Grid computing gets mentions in the press for community programs starting last decade with "Seti@Home". Government, national and supranational initiatives in grid receive some press. One of the IT-industries' best-kept secrets is the use of grid computing by commercial organizations with spectacular results. Grid Computing and its evolution into Application Virtualization is discussed and how this is key to the next generation data center. Speaker Bio: Fred Gedling holds the joint roles of Chief Technology Officer for EMEA and Senior Vice President of Global Services at DataSynapse, a global provider of application virtualisation software. Based in London and working closely with organisations seeking to optimise their IT infrastructures, Fred offers unique insights into the technology of virtualisation as well as the methodology of establishing ROI and rapid deployment to the immediate advantage of the business. Fred has more than fifteen years experience of enterprise middleware and high-performance infrastructures. Prior to DataSynapse he worked in high performance CRM middleware and was the CTO EMEA for New Era of Networks (NEON) during the rapid growth of Enterprise Application Integration. His 25-year career in technology also includes management positions at Goldman Sachs and Stratus Computer. Fred holds a First Class Bsc (Hons

  5. Computing for Finance

    ScienceCinema

    None

    2011-10-06

    with UBS for the past 9 years. During his tenure at UBS, he has had a number of leadership roles within IT in development, support and architecture. In 2006 Michael relocated to Switzerland to take up his current role as head of the UBS IB Technical Council, responsible for the overall technology strategy and vision of the Investment Bank. One of Michael's key responsibilities is to manage the UBS High Performance Computing Research Lab and he has been involved in a number of initiatives in the HPC space. 2. Grid in the Commercial WorldFred Gedling, Chief Technology Officer EMEA and Senior Vice President Global Services, DataSynapse Grid computing gets mentions in the press for community programs starting last decade with "Seti@Home". Government, national and supranational initiatives in grid receive some press. One of the IT-industries' best-kept secrets is the use of grid computing by commercial organizations with spectacular results. Grid Computing and its evolution into Application Virtualization is discussed and how this is key to the next generation data center. Speaker Bio: Fred Gedling holds the joint roles of Chief Technology Officer for EMEA and Senior Vice President of Global Services at DataSynapse, a global provider of application virtualisation software. Based in London and working closely with organisations seeking to optimise their IT infrastructures, Fred offers unique insights into the technology of virtualisation as well as the methodology of establishing ROI and rapid deployment to the immediate advantage of the business. Fred has more than fifteen years experience of enterprise middleware and high-performance infrastructures. Prior to DataSynapse he worked in high performance CRM middleware and was the CTO EMEA for New Era of Networks (NEON) during the rapid growth of Enterprise Application Integration. His 25-year career in technology also includes management positions at Goldman Sachs and Stratus Computer. Fred holds a First Class Bsc (Hons