Sample records for tropical mesoscale convective

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

    E-Print Network [OSTI]

    Johnson, Richard H.

    October 1986 R. H. Johnson 721 Lower-Tropospheric Warming and Drying in Tropical Mesoscale components of tropical mesoscale convective systems. It is found that while the apparent heat source Q1 of mesoscale downdrafts within the mesoscale convective systems. The warming and drying at low levels

  2. Vertical profiles of radar reflectivity of convective cells in tropical and mid-latitude mesoscale convective systems

    E-Print Network [OSTI]

    Lutz, Kurt Reed

    1992-01-01T23:59:59.000Z

    meteorological phenomenon of particular interest to forecasters is the mesoscale convective system (MCS). Chappell (1986) defines an MCS as "any multicellular storm or group of interacting storms that suggests some organization in its forcing". An MCS...VERTICAL PROFILES OF RADAR REFLECTIVITY OF CONVECTIVE CELLS IN TROPICAL AND MID-LATITUDE MESOSCALE CONVECTIVE SYSTEMS A Thesis by KURT REED LUTZ Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment...

  3. Properties of inflow and downdraft air of tropical mesoscale convective systems and the effect of downdrafts on the surface fluxes

    E-Print Network [OSTI]

    Griffith, Jeane Margaret

    1992-01-01T23:59:59.000Z

    PROPERTIES OF INFLOW AND DOWNDRAFT AIR OF TROPICAL MESOSCALE CONVECTIVE SYSTEMS AND THE EFFECT OF DOWNDRAFTS ON THE SURFACE FLUXES A Thesis by JEANE MARGARET GRIFFITH Submitted to the Office of Graduate Studies of Texas A&M University... in partial fulfillment of the requirements for the degree of MAS'IER OF SCIENCE December 1992 Major Subject: Meteorology PROPERTIES OF THE INFLOW AND DOWNDRAFT AIR OF TROPICAL MESOSCALE CONVECTIVE SYSTEMS AND THE EFFECT OF DOWNDRAFTS ON THE SURFACE...

  4. Passive microwave observations of mesoscale convective systems over the tropical Pacific Ocean

    E-Print Network [OSTI]

    McGaughey, Gary Rae

    1994-01-01T23:59:59.000Z

    This paper presents high resolution passive microwave measurements obtained in the western Pacific warm pool region. These measurements represent the first comprehensive observations of convection over the tropical oceans, and were obtained from...

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

    E-Print Network [OSTI]

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

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

    E-Print Network [OSTI]

    Devlin, Karen Irene

    1995-01-01T23:59:59.000Z

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

  7. MESOSCALE CONVECTIVE SYSTEMS Robert A. Houze Jr.

    E-Print Network [OSTI]

    Houze Jr., Robert A.

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

  8. Mesoscale Simulation of Tropical Cyclones in the South Pacific: Climatology and Interannual Variability

    E-Print Network [OSTI]

    Mesoscale Simulation of Tropical Cyclones in the South Pacific: Climatology and Interannual is shown to reproduce a wide range of mesoscale convective systems. Tropical cyclones grow from the most related to mesoscale in- teractions, which also affect TC tracks and the resulting occurrence. 1

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

    E-Print Network [OSTI]

    Hoofard, Michael Eugene

    1986-01-01T23:59:59.000Z

    MESOSCALE CONVECTIVE CCMPLLX VS. NON-MESOSCALE CONVECTIVE COMPLEX THUNDERSTORMS: A COMPARISON OF SELECTED METEOROLOGICAL VARIABLES A Thesis MICHAkL EUGENE JJOOFARD Submitted to the Graduate College of Texas AJkM University in partial... fulfillment of the requirements for the degree of MASTER OF SCIENCE August 1986 Major Subj ect: Meteorology MESOSCALE CONVECTIVE COMPLEX VS. NON-MESOSCALE CONVECTIVE COMPLEX THUNDERSTORMS: A COMPARISON OF SELECTED METEOROLOGICAL VARIABLES A Thesis...

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

    E-Print Network [OSTI]

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

    2007-01-01T23:59:59.000Z

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

  11. Analysis of Cloud-resolving Simulations of a Tropical Mesoscale Convective System Observed during TWP-ICE: Vertical Fluxes and Draft Properties in Convective and Stratiform Regions

    SciTech Connect (OSTI)

    Mrowiec, Agnieszka A.; Rio, Catherine; Fridlind, Ann; Ackerman, Andrew; Del Genio, Anthony D.; Pauluis, Olivier; Varble, Adam; Fan, Jiwen

    2012-10-02T23:59:59.000Z

    We analyze three cloud-resolving model simulations of a strong convective event observed during the TWP-ICE campaign, differing in dynamical core, microphysical scheme or both. Based on simulated and observed radar reflectivity, simulations roughly reproduce observed convective and stratiform precipitating areas. To identify the characteristics of convective and stratiform drafts that are difficult to observe but relevant to climate model parameterization, independent vertical wind speed thresholds are calculated to capture 90% of total convective and stratiform updraft and downdraft mass fluxes. Convective updrafts are fairly consistent across simulations (likely owing to fixed large-scale forcings and surface conditions), except that hydrometeor loadings differ substantially. Convective downdraft and stratiform updraft and downdraft mass fluxes vary notably below the melting level, but share similar vertically uniform draft velocities despite differing hydrometeor loadings. All identified convective and stratiform downdrafts contain precipitation below ~10 km and nearly all updrafts are cloudy above the melting level. Cold pool properties diverge substantially in a manner that is consistent with convective downdraft mass flux differences below the melting level. Despite differences in hydrometeor loadings and cold pool properties, convective updraft and downdraft mass fluxes are linearly correlated with convective area, the ratio of ice in downdrafts to that in updrafts is ~0.5 independent of species, and the ratio of downdraft to updraft mass flux is ~0.5-0.6, which may represent a minimum evaporation efficiency under moist conditions. Hydrometeor loading in stratiform regions is found to be a fraction of hydrometeor loading in convective regions that ranges from ~10% (graupel) to ~90% (cloud ice). These findings may lead to improved convection parameterizations.

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

    E-Print Network [OSTI]

    Miami, University of

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

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

    E-Print Network [OSTI]

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

  14. Cold domes over the warm pool: a study of the properties of cold domes produced by mesoscale convective systems during TOGA COARE

    E-Print Network [OSTI]

    Caesar, Kathy-Ann Lois

    1995-01-01T23:59:59.000Z

    Mesoscale convective systems (MCSs) are known to cool the subcloud layer by the introduction of penetrative downdrafts to the surface, resulting in the formation of cold domes (also known as cold pools). Five MCSs sampled during the Tropical Ocean...

  15. Evolution of moisture convergence in a mesoscale convective complex

    E-Print Network [OSTI]

    Bercherer, John Phillip

    1990-01-01T23:59:59.000Z

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

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

    E-Print Network [OSTI]

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

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

    E-Print Network [OSTI]

    Cummer, Steven A.

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

  18. Patterns of Precipitation and Mesolow Evolution in Midlatitude Mesoscale Convective Vortices

    E-Print Network [OSTI]

    Johnson, Richard H.

    Patterns of Precipitation and Mesolow Evolution in Midlatitude Mesoscale Convective Vortices ERIC P manifestations of mesoscale convective vortices (MCVs) that traversed Oklahoma during the periods May­August 2002 Profiler Network data. Forty-five MCVs that developed from mesoscale convective systems (MCSs) have been

  19. Precipitation Hydrometeor Type Relative to the Mesoscale Airflow in Oceanic Deep Convection of the Madden-Julian Oscillation

    E-Print Network [OSTI]

    Houze Jr., Robert A.

    1 Precipitation Hydrometeor Type Relative to the Mesoscale Airflow in Oceanic Deep located relative to mesoscale air motions Heavy rain and riming occur downstream of mesoscale Abstract Composite analysis of near-equatorial oceanic mesoscale convective systems (MCSs

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

    E-Print Network [OSTI]

    Johnson, Richard H.

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

  1. Analysis of 11 june 2003 mesoscale convective vortex genesis using weather surveillance radar ??88 doppler (wsr-88d) 

    E-Print Network [OSTI]

    Reynolds, Amber Elizabeth

    2009-05-15T23:59:59.000Z

    Mesoscale convective vortices (MCVs), which typically form within the stratiform rain of some mesoscale convective systems (MCSs), may persist for days, often regenerating convection daily. Long-lived MCVs can produce as much precipitation as a...

  2. Analysis of 11 june 2003 mesoscale convective vortex genesis using weather surveillance radar ??88 doppler (wsr-88d)

    E-Print Network [OSTI]

    Reynolds, Amber Elizabeth

    2009-05-15T23:59:59.000Z

    Mesoscale convective vortices (MCVs), which typically form within the stratiform rain of some mesoscale convective systems (MCSs), may persist for days, often regenerating convection daily. Long-lived MCVs can produce as much precipitation as a...

  3. Thermodynamic properties of mesoscale convective systems observed during BAMEX

    SciTech Connect (OSTI)

    Correia, James; Arritt, R.

    2008-11-01T23:59:59.000Z

    Dropsonde observations from the Bow-echo and Mesoscale convective vortex EXperiment (BAMEX) are used to document the spatio-temporal variability of temperature, moisture and wind within mesoscale convective systems (MCSs). Onion type sounding structures are found throughout the stratiform region of MCSs but the temperature and moisture variability is large. Composite soundings were constructed and statistics of thermodynamic variability were generated within each sub-region of the MCS. The calculated air vertical velocity helped identify subsaturated downdrafts. We found that lapse rates within the cold pool varied markedly throughout the MCS. Layered wet bulb potential temperature profiles seem to indicate that air within the lowest several km comes from a variety of source regions. We also found that lapse rate transitions across the 0 C level were more common than isothermal, melting layers. We discuss the implications these findings have and how they can be used to validate future high resolution numerical simulations of MCSs.

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

    E-Print Network [OSTI]

    Pardo-Carrión, Juan R.

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

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

    E-Print Network [OSTI]

    Spiga, Aymeric

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

  6. Transient luminous events above two mesoscale convective systems: Charge moment change analysis

    E-Print Network [OSTI]

    Rutledge, Steven

    Transient luminous events above two mesoscale convective systems: Charge moment change analysis that were parents of transient luminous events (TLEs; mainly sprites) over two different storms: 9 May (20. A. Rutledge, and D. R. MacGorman (2011), Transient luminous events above two mesoscale convective

  7. Charge transfer and in-cloud structure of large-charge-moment positive lightning strokes in a mesoscale convective system

    E-Print Network [OSTI]

    Cummer, Steven A.

    in a mesoscale convective system Gaopeng Lu,1 Steven A. Cummer,1 Jingbo Li,1 Feng Han,1 Richard J. Blakeslee,2 positive cloud-to-ground (+CG) strokes in a mesoscale convective system. Although no high altitude images of large-charge-moment positive lightning strokes in a mesoscale convective system, Geophys. Res. Lett., 36

  8. Mesoscale eddies in the northeastern Pacific tropical-subtropical transition zone: Statistical characterization from satellite altimetry

    E-Print Network [OSTI]

    Mesoscale eddies in the northeastern Pacific tropical-subtropical transition zone: Statistical February 2012; revised 24 August 2012; accepted 6 September 2012; published 24 October 2012. [1] Mesoscale cycle. Although mesoscale eddies in these areas have been previously reported, this study provides

  9. Evolution of vertical drafts and cloud-to-ground lightning within the convective region of a mesoscale convective complex

    E-Print Network [OSTI]

    Saul, Scott Henry

    1995-01-01T23:59:59.000Z

    The evolution of the area-averaged vertical velocity within the objectively defined convective region of the 4 June 1985 PRE-STORM (Preliminary Regional Experiment for Stormscale Operational and Research Meteorology-Central Phase) mesoscale...

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

    E-Print Network [OSTI]

    Niyogi, Dev

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

  11. Convective variability associated with a mesoscale vortex in a midlatitude squall line system

    E-Print Network [OSTI]

    Hristova-Veleva, Svetla M.

    1994-01-01T23:59:59.000Z

    The relationship between the kinematic structure of the convective line and the mesoscale stortn-relative flow associated with an embedded mesovortex in the trailing stratiform region of the 28 May 1985 squall line system is examined using Doppler...

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

    E-Print Network [OSTI]

    Hovis, Jeffrey Scott

    1988-01-01T23:59:59.000Z

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

  13. Anatomy and evolution of a cyclonic mesoscale eddy observed in the northeastern Pacific tropical-subtropical transition zone

    E-Print Network [OSTI]

    Anatomy and evolution of a cyclonic mesoscale eddy observed in the northeastern Pacific tropical and evolution of a cyclonic mesoscale eddy observed in the northeastern Pacific tropical-subtropical transition zone, J. Geophys. Res. Oceans, 118, doi:10.1002/ 2013JC009339. 1. Introduction [2] Mesoscale eddy

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

    E-Print Network [OSTI]

    Thomas, Jeremy N.

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

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

    E-Print Network [OSTI]

    F. Rincon; F. Lignieres; M. Rieutord

    2006-11-28T23:59:59.000Z

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

  16. A Statistical Analysis of Characteristics of Mesoscale Convective System Mountain Initiation Location Clusters in the Arkansas-Red River Basin

    E-Print Network [OSTI]

    Callen, Elisabeth F.

    2012-12-31T23:59:59.000Z

    Mesoscale Convective Systems (MCSs) are the focus of this analysis since it is the convective weather category which is smallest in number but produces the highest amount of precipitation. Being able to forecast these MCSs ...

  17. Generation of mesoscale convective structures in tokamak edge plasma

    SciTech Connect (OSTI)

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

    2007-10-15T23:59:59.000Z

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

  18. The convective structures associated with cloud-to-ground lightning in TOGA COARE Mesoscale Convective Systems

    E-Print Network [OSTI]

    Restivo, Michael Edward

    1995-01-01T23:59:59.000Z

    suggested that the threshold of about 40 dBZ at the -10 C level for rapid cloud electrification found in New Mexico by Dye et al. (1989) could be valid for tropical convection as well. Orville and Henderson (1986), and Goodman and Christian (1993), have... along with small ice and supercooled liquid water for cloud electrification and lightning to occur. Since most oceanic VPRR drop off rapidly above the freezing level compared to continental VPRR, this would provide evidence that the updraft velocities...

  19. The Dynamics and Predictability of Tropical Cyclones

    E-Print Network [OSTI]

    Sippel, Jason A.

    2010-01-15T23:59:59.000Z

    Through methodology unique for tropical cyclones in peer-reviewed literature, this study explores how the dynamics of moist convection affects the predictability of tropical cyclogenesis. Mesoscale models are used to perform short-range ensemble...

  20. Quality of the Target Area for Metrics with Different Nonlinearities in a Mesoscale Convective System

    E-Print Network [OSTI]

    Meng, Zhiyong

    , on the forecast error of strongly nonlinear rainfall and weakly nonlinear total energy around the initial vortex of Atmospheric and Oceanic Sciences, School of Physics, Peking University, Beijing, China (Manuscript received 31 area for forecast metrics with different nonlinearities in a mesoscale convective vortex

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

    E-Print Network [OSTI]

    Ebert, Beth

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

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

    E-Print Network [OSTI]

    Houze Jr., Robert A.

    2006-01-01T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Hoeth, Brian Richard

    1998-01-01T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Hodapp, Charles Lee

    2009-05-15T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

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

  6. A case study of the mesoscale and synoptic-scale heat and moisture budgets in the vicinity of a mesoscale convective complex

    E-Print Network [OSTI]

    Dial, Greg Leander

    1990-01-01T23:59:59.000Z

    A CASE STUDY OF THE MESOSCALE AND SYNOPTIC-SCALE HEAT AND MOISTURE BUDGETS IN THE VICINITY OF A MESOSCALE CONVECTIVE COMPLEX A Thesis by GREG LEANDER DIAL Submitted to the Office of Graduate Studies of Texas A8 M University in partial...&j Leandor Dial Approved as lo style and content by: Kcnnctt& C, ftrunrti&lgc (Ctn&i& ol' Co&nn&ittcc) (I tcn&l&c&) Norman W. Na glc (Mcmbcr) E ar . ipscr (I les&I of Dcpartmcnt) I 1 a y I 9 &3 0 ABSTRACT A Case Study of the Mesoscale and Synoptic...

  7. Stochastic and mesoscopic models for tropical convection

    E-Print Network [OSTI]

    Majda, Andrew J.

    Courant Institute of Mathematical Sciences and Center for Atmosphere and Ocean Sciences, New York penetrative convection to heights of 5­10 km with associated anvil towers of clouds. Observational data

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

    E-Print Network [OSTI]

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

    2006-01-01T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

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

    2014-11-27T23:59:59.000Z

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

  10. Simulated diurnal rainfall physics in a multi-scale global climate model with embedded explicit convection

    E-Print Network [OSTI]

    Pritchard, Michael Stephen

    2011-01-01T23:59:59.000Z

    2.8: Relationship among mesoscale convective complex (MCC)C. J. Anderson, 2008: Idealized mesoscale convective system205. Houze, R. , 2004: Mesoscale convective systems. Reviews

  11. Tropical ozone as an indicator of deep convection Ian Folkins and Christopher Braun

    E-Print Network [OSTI]

    Folkins, Ian

    Tropical ozone as an indicator of deep convection Ian Folkins and Christopher Braun Department] The climatological ozone profile in the tropics is shaped like an ``S,'' with a minimum at the surface, a maximum. These features can be reproduced by a very simple model whose only free parameter is the mean ozone mixing ratio

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

    E-Print Network [OSTI]

    Xie, Shang-Ping

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

  13. On the effect of the steady-state approximation in time-space composite studies of mesoscale convective systems

    E-Print Network [OSTI]

    Mattison, Kevin Morgan

    1992-01-01T23:59:59.000Z

    ON THE EFFECT OF THE STRA 'Y-STATE APPROXIMATION IN TIME-SPACE COMPOSITE STUDIES OF MESOSCALE CONVECTIVE SYSTEMS A Thesis KEVIN MORGAN MATTISON Subnitted to the Office of Graduate Studies of Texas A&M University in partial fulfillnent... of the requirements for the degree of MASTER OF SCIENCE Decenber 1992 Major Subject: Meteorology ON THE EFFECT OF THE STEADY-STATE APPROXINATIOH IN TIME-SPACE COMPOSITE STUDIES OF NESOSCALE COHVECTIVE SYSTENS A Thesis KEVIN MORGAN NATTISOH Approved as to style...

  14. 13B.7 THE CLIMATOLOGY, CONVECTIVE MODE, AND MESOSCALE ENVIRONMENT OF COOL SEASON SEVERE THUNDERSTORMS IN THE OHIO AND TENNESSEE VALLEYS, 1995-2006

    E-Print Network [OSTI]

    2300, Norman, OK 73072, E-mail: Bryan.Smith@noaa.gov Center hourly mesoanalysis data (Bothwell et al System (GIS). Using these data, we define a tornado day as a 24 hr period beginning at the first reported13B.7 THE CLIMATOLOGY, CONVECTIVE MODE, AND MESOSCALE ENVIRONMENT OF COOL SEASON SEVERE

  15. Transient luminous events above two mesoscale convective systems: Storm structure and evolution

    E-Print Network [OSTI]

    Rutledge, Steven

    structure and evolution Timothy J. Lang,1 Walter A. Lyons,2 Steven A. Rutledge,1 Jonathan D. Meyer,2. Meyer, D. R. MacGorman, and S. A. Cummer (2010), Transient luminous events above two mesoscale, are thought to result from dielectric breakdown at approximately 75 km height [Stanley et al., 1999

  16. Vertical structure of tropical oceanic convective clouds and its relation to precipitation

    E-Print Network [OSTI]

    Hartmann, Dennis

    data are collocated with precipitation rates from the Advanced Microwave Scanning Radiometer (AMSR high tops that are nearly two km deeper than moderately raining or non- raining high clouds. Rain rate.1029/2007GL032811. 1. Introduction [2] Tropical convection plays an important role in the energy and moisture

  17. Observations, dynamics and predictability of the mesoscale convective vortex event of 10-13 June 2003

    E-Print Network [OSTI]

    Hawblitzel, Daniel Patrick

    2006-08-16T23:59:59.000Z

    with varying resolutions. It is determined that the ability of a forecast model to accurately predict this MCV event is directly related to its ability to simulate convection. It is also shown that the convective-resolving Weather Research and Forecast (WRF...

  18. Environment and the Lifetime of Tropical Deep Convection in a Cloud-Permitting Regional Model Simulation

    SciTech Connect (OSTI)

    Hagos, Samson M.; Feng, Zhe; McFarlane, Sally A.; Leung, Lai-Yung R.

    2013-08-01T23:59:59.000Z

    By applying a cloud tracking algorithm to tropical convective systems simulated by a regional high resolution model, the study documents environmental conditions before and after convective systems are initiated over ocean and land by following them during their lifetime. The comparative roles of various environmental fields in affecting the lifetime of convection are also quantified. The statistics of lifetime, maximum area, propagation speed and direction of the simulated deep convection agrees well with geostationary satellite observations. Over ocean, convective systems enhance surface fluxes through the associated wind gusts as well as cooling and drying of the boundary layer. A significant relationship is found between the mean surface fluxes during their lifetime and the longevity of the systems which in turn is related to the initial intensity of the moist updraft and to a lesser extent upper level shear. Over land, on the other hand, convective activity suppresses surface fluxes through cloud cover and the lifetime of convection is related to the upper level shear during their lifetime and strength of the heat fluxes several hours before the initiation of convection. For systems of equal lifetime, those over land are significantly more intense than those over ocean especially during early stages of their lifetime.

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

    E-Print Network [OSTI]

    Humbert, Mark Edward

    1980-01-01T23:59:59.000Z

    with convection is upward motion at all levels with a maximum value just prior to max1mum convect1ve intensity. Days without convection showed a cont1nual vertical turbulent m1xing of moisture from a shallow boundary layer to the 700 mb level. Lack... of 4 g kg 1 are observed. The moisture content increases at the 22 Post Big Spring Midland Robert Lee 4 500 mb cn 0 O m 8 L. cn 6 x 4 2 700 mb . . ~ ''. ~' . ~ / r 12 10 850 mb 15 18 21 00 03 Time (GNT hours) Fig. 9. Time profiles...

  20. Radar, satellite, and lightning characteristics of select mesoscale convective systems in Texas

    E-Print Network [OSTI]

    Toracinta, Ernest Richard

    1995-01-01T23:59:59.000Z

    , the observation of high negative flash counts coincident with convective cores having small reflectivity lapse rates in the mixed phase region is consistent with the presence of large ice particles aloft. Positive CG flashes were mostly located in low reflectivity...

  1. The sensitivity of tropical convective precipitation to the direct radiative forcings of black carbon aerosols emitted from major regions

    E-Print Network [OSTI]

    Wang, Chien

    Previous works have suggested that the direct radiative forcing (DRF) of black carbon (BC) aerosols are able to force a significant change in tropical convective precipitation ranging from the Pacific and Indian Ocean to ...

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

    E-Print Network [OSTI]

    Shaw, Justin David

    2000-01-01T23:59:59.000Z

    in the lowest 2.5 km varying from 10-25 m s?¹. A fourth simulation was conducted using the weak wind shear profile and incorporating ice microphysics. An analysis domain was produced every two hours for the northern and southern portions of the convective line...

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

    E-Print Network [OSTI]

    Shaw, Justin David

    2000-01-01T23:59:59.000Z

    in the lowest 2.5 km varying from 10-25 m s?¹. A fourth simulation was conducted using the weak wind shear profile and incorporating ice microphysics. An analysis domain was produced every two hours for the northern and southern portions of the convective line...

  4. Radiative sensitivities of tropical anvils to small ice crystals

    E-Print Network [OSTI]

    Zender, Charles S.; Kiehl, J. T.

    2012-01-01T23:59:59.000Z

    Jr. , Water budget of mesoscale convective system in theJr. , The contribution of mesoscale motions to the mass andpresence of a gentle mesoscale vertical updraft to supply

  5. A comparison of tropical mesoscale convective systems in El Nino and La Nina

    E-Print Network [OSTI]

    Zolman, Jody Lynn

    1999-01-01T23:59:59.000Z

    . Snow exclusion areas (After Mohr and Zipser 1996b). January Area Elevation m 65-83W 10N-20S &4000 65-75W 20-25S &3800 65-75W 65-75W 0-1 OW 30-50E 50-110E 25-30S 30-35S 25-35N 30-35N 25-35N &3600 &3000 ALL ALL ALL February Area Elevation...(m) 65-83W 5N-20S &4000 65-75W 20-30S &3500 65-75W 0-1 OW 30-35S 25-35N &3000 ALL 30-50E 50-120E 90-120E 30-35N 25-35N 25-35N ALL &1000 &800 March Area Elevation m) April Area Elevation m) May Area Elevation(m June Area Elevation...

  6. Convective Signals from Surface Measurements at ARM Tropical Western Pacific Site: Manus

    SciTech Connect (OSTI)

    Wang, Yi; Long, Charles N.; Mather, James H.; Liu, Xiaodong

    2011-02-23T23:59:59.000Z

    The Madden-Julian Oscillation (MJO) signal has been detected using observations from the Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Climate Research Facility (ACRF) Tropical Western Pacific (TWP). With downwelling shortwave radiative fluxes and fractional sky cover from the ACRF TWP Manus site, and the statistical tools of wavelet and spectrum power, we report finding major convective signals from surface observations spanning the period from 1996 to 2006. Our findings are confirmed with the satellite-retrieved values of precipitation from the Global Precipitation Climatology Project (GPCP), and interpolated outgoing longwave radiation (OLR) satellite measurements from the National Oceanic and Atmospheric Administration (NOAA) for the same location. Our results indicate that the MJO convective signal has a strong seasonal-to-interannual evolution that is likely correlated with the interannual variability of El Ni ˜no Southern Oscillation (ENSO).

  7. Final Technical Report for "Radiative Heating Associated with Tropical Convective Cloud Systems: Its Importance at Meso and Global Scales"

    SciTech Connect (OSTI)

    Schumacher, Courtney

    2012-12-13T23:59:59.000Z

    Heating associated with tropical cloud systems drive the global circulation. The overall research objectives of this project were to i) further quantify and understand the importance of heating in tropical convective cloud systems with innovative observational techniques, and ii) use global models to determine the large-scale circulation response to variability in tropical heating profiles, including anvil and cirrus cloud radiative forcing. The innovative observational techniques used a diversity of radar systems to create a climatology of vertical velocities associated with the full tropical convective cloud spectrum along with a dissection of the of the total heating profile of tropical cloud systems into separate components (i.e., the latent, radiative, and eddy sensible heating). These properties were used to validate storm-scale and global climate models (GCMs) and were further used to force two different types of GCMs (one with and one without interactive physics). While radiative heating was shown to account for about 20% of the total heating and did not have a strong direct response on the global circulation, the indirect response was important via its impact on convection, esp. in how radiative heating impacts the tilt of heating associated with the Madden-Julian Oscillation (MJO), a phenomenon that accounts for most tropical intraseasonal variability. This work shows strong promise in determining the sensitivity of climate models and climate processes to heating variations associated with cloud systems.

  8. Statistical representation of clouds in a regional model and the impact on the diurnal cycle of convection during Tropical

    E-Print Network [OSTI]

    Chaboureau, Jean-Pierre

    water static energy. Application of the parameterization in a regional model during a 30-day period of the Tropical Convection, Cirrus and Nitrogen Oxides (TROCCINOX) experiment over southern Brazil demonstrates of cloud mass at tropospheric inversions (e.g., trade wind inversion, melting level, tropo- pause

  9. Radiative and Convective Driving of Tropical High Clouds TERENCE L. KUBAR, DENNIS L. HARTMANN, AND ROBERT WOOD

    E-Print Network [OSTI]

    Wood, Robert

    ). It is also shown that thin high cloud, which has a positive net radiative effect on the topRadiative and Convective Driving of Tropical High Clouds TERENCE L. KUBAR, DENNIS L. HARTMANN thick high cloud, which is a better proxy for precipitation than outgoing longwave radiation (OLR

  10. The QBO's influence on lightning production and deep convection in the tropics

    E-Print Network [OSTI]

    Hernandez, Celina Anne

    2009-05-15T23:59:59.000Z

    ) flash densities and ten years (1998-2007) of TRMM Precipitation Radar (PR) deep convective and stratiform rainfall and convective echo top heights are analyzed. The QBO can be linked to deep convection through two hypothesized mechanisms: 1) modulation...

  11. Convective-Scale Variations in the Inner-Core Rainbands of a Tropical Cyclone ANTHONY C. DIDLAKE JR. AND ROBERT A. HOUZE JR.

    E-Print Network [OSTI]

    Houze Jr., Robert A.

    Convective-Scale Variations in the Inner-Core Rainbands of a Tropical Cyclone ANTHONY C. DIDLAKE JR secondary eyewall forms at a certain radius, subsidence occurring along its inner edge separates it from the primary eyewall. 1. Introduction Improving intensity forecasts of tropical cyclones al- most certainly

  12. Convective-scale variations in the inner-core rainbands of a tropical cyclone Submitted for publication in Journal of the Atmospheric Sciences

    E-Print Network [OSTI]

    Houze Jr., Robert A.

    Convective-scale variations in the inner-core rainbands of a tropical cyclone Submitted inner edge separates it from the primary eyewall. #12;3 1. Introduction Improving intensity forecasts of tropical cyclones almost certainly requires a better understanding of the structure and dynamics

  13. Convective signals from surface measurements at ARM Tropical Western Pacific site: Manus

    SciTech Connect (OSTI)

    Wang, Yi; Long, Charles N.; Mather, James H.; Liu, Xiaodong

    2011-02-04T23:59:59.000Z

    Madden-Julian Oscillation (MJO) signals have been detected using highly sampled observations from the U.S. DOE ARM Climate Research Facility located at the Tropical Western Pacific Manus site. Using downwelling shortwave radiative fluxes and derived shortwave fractional sky cover, and the statistical tools of wavelet, cross wavelet, and Fourier spectrum power, we report finding major convective signals and their phase change from surface observations spanning from 1996 to 2006. Our findings are confirmed with the satellite-gauge combined values of precipitation from the NASA Global Precipitation Climatology Project and the NOAA interpolated outgoing longwave radiation for the same location. We find that the Manus MJO signal is weakest during the strongest 1997-1998 El Nin˜o Southern Oscillation (ENSO) year. A significant 3-5-month lead in boreal winter is identified further between Manus MJO and NOAA NINO3.4 sea surface temperature (former leads latter). A striking inverse relationship is found also between the instantaneous synoptic and intraseasonal phenomena over Manus. To further study the interaction between intraseasonal and diurnal scale variability, we composite the diurnal cycle of cloudiness for 21-MJO events that have passed over Manus. Our diurnal composite analysis of shortwave and longwave fractional sky covers indicates that during the MJO peak (strong convection), the diurnal amplitude of cloudiness is reduced substantially, while the diurnal mean cloudiness reaches the highest value and there are no significant phase changes. We argue that the increasing diurnal mean and decreasing diurnal amplitude are caused by the systematic convective cloud formation that is associated with the wet phase of the MJO, while the diurnal phase is still regulated by the well-defined solar forcing. This confirms our previous finding of the anti-phase relationship between the synoptic and intraseasonal phenomena. The detection of theMJOover the Manus site provides further opportunities in using other ground-based remote sensing instruments to investigate the vertical distributions of clouds and radiative heatings of the MJO that currently is impossible from satellite observations.

  14. Precipitation characteristics of CAM5 physics at mesoscale resolution during MC3E and the impact of convective timescale choice

    SciTech Connect (OSTI)

    Gustafson, William I.; Ma, Po-Lun; Singh, Balwinder

    2014-12-01T23:59:59.000Z

    The physics suite of the Community Atmosphere Model version 5 (CAM5) has recently been implemented in the Weather Research and Forecasting (WRF) model to explore the behavior of the parameterization suite at high resolution and in the more controlled setting of a limited area model. The initial paper documenting this capability characterized the behavior for northern high latitude conditions. This present paper characterizes the precipitation characteristics for continental, mid-latitude, springtime conditions during the Midlatitude Continental Convective Clouds Experiment (MC3E) over the central United States. This period exhibited a range of convective conditions from those driven strongly by large-scale synoptic regimes to more locally driven convection. The study focuses on the precipitation behavior at 32 km grid spacing to better anticipate how the physics will behave in the global model when used at similar grid spacing in the coming years. Importantly, one change to the Zhang-McFarlane deep convective parameterization when implemented in WRF was to make the convective timescale parameter an explicit function of grid spacing. This study examines the sensitivity of the precipitation to the default value of the convective timescale in WRF, which is 600 seconds for 32 km grid spacing, to the value of 3600 seconds used for 2 degree grid spacing in CAM5. For comparison, an infinite convective timescale is also used. The results show that the 600 second timescale gives the most accurate precipitation over the central United States in terms of rain amount. However, this setting has the worst precipitation diurnal cycle, with the convection too tightly linked to the daytime surface heating. Longer timescales greatly improve the diurnal cycle but result in less precipitation and produce a low bias. An analysis of rain rates shows the accurate precipitation amount with the shorter timescale is assembled from an over abundance of drizzle combined with too little heavy rain events. With longer timescales one can improve the distribution, particularly for the extreme rain rates. Ultimately, without changing other aspects of the physics, one must choose between accurate diurnal timing and rain amount when choosing an appropriate convective timescale.

  15. Impact of Aerosols on Tropical Cyclones: An Investigation Using Convection-permitting Model Simulation

    SciTech Connect (OSTI)

    Hazra, Anupam; Mukhopadhyay, P.; Taraphdar, Sourav; Chen, J. P.; Cotton, William R.

    2013-07-16T23:59:59.000Z

    The role of aerosols effect on two tropical cyclones over Bay of Bengal are investigated using a convection permitting model with two-moment mixed-phase bulk cloud microphysics scheme. The simulation results show the role of aerosol on the microphysical and dynamical properties of cloud and bring out the change in efficiency of the clouds in producing precipitation. The tracks of the TCs are hardly affected by the changing aerosol types, but the intensity exhibits significant sensitivity due to the change in aerosol contribution. It is also clearly seen from the analyses that higher heating in the middle troposphere within the cyclone center is in response to latent heat release as a consequence of greater graupel formation. Greater heating in the middle level is particularly noticeable for the clean aerosol regime which causes enhanced divergence in the upper level which, in turn, forces the lower level convergence. As a result, the cleaner aerosol perturbation is more unstable within the cyclone core and produces a more intense cyclone as compared to other two perturbations of aerosol. All these studies show the robustness of the concept of TC weakening by storm ingestion of high concentrations of CCN. The consistency of these model results gives us confidence in stating there is a high probability that ingestion of high CCN concentrations in a TC will lead to weakening of the storm but has little impact on storm direction. Moreover, as pollution is increasing over the Indian sub-continent, this study suggests pollution may be weakening TCs over the Bay of Bengal.

  16. Equilibrium Tropical Cyclone Size in an Idealized State of Axisymmetric Radiative–Convective Equilibrium*

    E-Print Network [OSTI]

    Chavas, Daniel R.

    Tropical cyclone size remains an unsolved problem in tropical meteorology, yet size plays a significant role in modulating damage. This work employs the Bryan cloud model (CM1) to systematically explore the sensitivity of ...

  17. Constructing a Merged CloudPrecipitation Radar Dataset for Tropical Convective Clouds during the DYNAMO/AMIE Experiment at Addu Atoll

    E-Print Network [OSTI]

    of observations from three radars--the S-band dual-polarization Doppler radar (S-Pol), the C-band Shared Mobile, and radiative heating rate retrievals. With this dataset the full spectrum of tropical convective clouds during, U.S. Department of Energy, Washington, D.C. Corresponding author address: Dr. Zhe Feng, Pacific

  18. Convective structure in rapidly intensifying tropical cyclones as depicted by passive microwave measurements

    E-Print Network [OSTI]

    Nesbitt, Steve

    include: mesovorticies [Nolan and Montgomery, 2002], convective asymmetries [Braun et al., 2006], and vortical hot towers (VHTs) under high wind shear [Molinari and Vollaro, 2010]. Conversely, RI has been

  19. Convection?

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power Administration would likeConstitution AndControlling Graphene's ElectronicnewConvection What

  20. EQUILIBRIUM VS. ACTIVATION CONTROL OF LARGE-SCALE VARIATIONS OF TROPICAL DEEP CONVECTION

    E-Print Network [OSTI]

    Mapes, Brian

    convective cloud systems. This essay highlights the distinction between processes which supply moisture separations of the LSVDC problem are reviewed. Scale separation, though rigorous, is artificial, since net cloudiness, are exam- ined as examples. Lower boundary flux enhancements and deep lifting exert both

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

    E-Print Network [OSTI]

    Raman, Sethu

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

  2. The kinematic and cloud-to-ground lightning structure of the 9-10, June 1998 Red River Mesoscale Convective System

    E-Print Network [OSTI]

    Santarpia, Joshua

    2001-01-01T23:59:59.000Z

    interest in using it to study severe weather. Mesoscale vortices that are often asso- ciated with severe storms such as supercells and bow echoes have been of particular interest. One of the first discussions of this type of circulation is from Brooks... radar echoes associated with a tornado indicating a cyclonic circulation. He likened the structure to that of a small-scale hurricane. Ray's (1976) dual-Doppler radar analysis of a supercell storm was the first to show a vortex pair and strong cy...

  3. Materials at the Mesoscale

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

    Materials at the Mesoscale 1663 Los Alamos science and technology magazine Latest Issue:January 2015 All Issues submit Materials at the Mesoscale Los Alamos's bold proposal to...

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

    E-Print Network [OSTI]

    Niyogi, Dev

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

  5. Tropical precipitation variability and convectively coupled equatorial waves1 on submonthly time-scales in reanalyses and TRMM2

    E-Print Network [OSTI]

    Alexander, M. Joan

    convection plays a vital role in global climate by driving large-scale circulation,41 releasing latent heat, modulating radiative forcing, and most importantly redistributing water in42 the earth system. Due to complex

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

    E-Print Network [OSTI]

    Niyogi, Dev

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

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

    SciTech Connect (OSTI)

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

    2013-11-13T23:59:59.000Z

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

  8. Structure and evolution of a convective band MCS

    E-Print Network [OSTI]

    Valdes-Manzanilla, Arturo

    1995-01-01T23:59:59.000Z

    circulation of the Mesoscale Convective Complex apparently aided in the formation of new lines of convection behind the primary convective line of the system. This process was repeated twice in the storm life cycle and led to multiple bands of convection...

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

    SciTech Connect (OSTI)

    Heymsfield, A.

    1997-09-01T23:59:59.000Z

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

  10. Constructing a Merged Cloud-Precipitation Radar Dataset for Tropical Convective Clouds during the DYNAMO/AMIE Experiment at Addu Atoll

    SciTech Connect (OSTI)

    Feng, Zhe; McFarlane, Sally A.; Schumacher, Courtney; Ellis, Scott; Comstock, Jennifer M.; Bharadwaj, Nitin

    2014-05-16T23:59:59.000Z

    To improve understanding of the convective processes key to the Madden-Julian-Oscillation (MJO) initiation, the Dynamics of the MJO (DYNAMO) and Atmospheric Radiation Measurement MJO Investigation Experiment (AMIE) collected four months of observations from three radars, the S-band Polarization Radar (S-Pol), the C-band Shared Mobile Atmospheric Research & Teaching Radar (SMART-R), and Ka-band Zenith Radar (KAZR) on Addu Atoll in the tropical Indian Ocean. This study compares the measurements from the S-Pol and SMART-R to those from the more sensitive KAZR in order to characterize the hydrometeor detection capabilities of the two scanning precipitation radars. Frequency comparisons for precipitating convective clouds and non-precipitating high clouds agree much better than non-precipitating low clouds for both scanning radars due to issues in ground clutter. On average, SMART-R underestimates convective and high cloud tops by 0.3 to 1.1 km, while S-Pol underestimates cloud tops by less than 0.4 km for these cloud types. S-Pol shows excellent dynamic range in detecting various types of clouds and therefore its data are well suited for characterizing the evolution of the 3D cloud structures, complementing the profiling KAZR measurements. For detecting non-precipitating low clouds and thin cirrus clouds, KAZR remains the most reliable instrument. However, KAZR is attenuated in heavy precipitation and underestimates cloud top height due to rainfall attenuation 4.3% of the time during DYNAMO/AMIE. An empirical method to correct the KAZR cloud top heights is described, and a merged radar dataset is produced to provide improved cloud boundary estimates, microphysics and radiative heating retrievals.

  11. JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 98, NO. D5, PAGES 8695-8711, MAY 20, 1993 The Radiative Budgets of a Tropical MesoscaleConvective System

    E-Print Network [OSTI]

    Stephens, Graeme L.

    . The value of this total heating is governedby both infrared and solar absorption. Vertical profiles of this heating show the dominance of infrared cooling near cloud top and infrared heating inside and near cloud base. The shortwave heating rate can also be as large as the infrared coolingnear the cloud top region

  12. Closing the Mesoscale Gap

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

    Closing the Mesoscale Gap Los Alamos proposes to fill in the gaps in our fundamental understanding of materials with MaRIE, a facility designed to gain access to the mesoscale....

  13. Hydration of the lower stratosphere by ice crystal geysers over land convective systems

    E-Print Network [OSTI]

    Khaykin, S.

    The possible impact of deep convective overshooting over land has been explored by six simultaneous soundings of water vapour, particles and ozone in the lower stratosphere next to Mesoscale Convective Systems (MCSs) during ...

  14. The multiple vortex nature of tropical cyclogenesis

    E-Print Network [OSTI]

    Sippel, Jason Allen

    2005-02-17T23:59:59.000Z

    cells and vortices are the respective source of PV production and building blocks for the meso-?-scale vortices. Finally, this thesis discusses issues related to the multiple vortex nature of tropical cyclone formation. For instance, the tracking...

  15. Search for: mesoscale | DOE PAGES

    Office of Scientific and Technical Information (OSTI)

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

  16. Mesoscale Modeling Spring Semester 2014

    E-Print Network [OSTI]

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

  17. Convective cell development and propagation in a mesoscale convective complex

    E-Print Network [OSTI]

    Ahn, Yoo-Shin

    1987-01-01T23:59:59.000Z

    ? ? ? ? ? ? ? ? ? ? 18 8A VIP level 1 cell outlines at hourly intervals from 0000 to 0800 GNT- 21 SB As in Fig. SA except from 0901 to 1558 GMT- 22 9A VIP level 3 cell outlines at 20 min intervals from 0120 to 0700 GMT- ? 24 9B As in Fig. 9A except from 0721... to 1240 GMT- ? ? ? ? ? ? ? ? ? ? 25 10 dodographs at 1200 GMT for OKC (solid) and SEP (dashed) ? ? ? ? 27 11 VIP level 1 cell centroid positions at hourly intervals from 0000 to 1558 GMT 29 12 Gust front and VIP level 3 cell positions at hourly...

  18. The Generation of a Mesoscale Convective System from Mountain Convection

    E-Print Network [OSTI]

    Tucker, Donna F.; Crook, N. Andrew

    1999-06-01T23:59:59.000Z

    . Heights are contoured with solid lines every 60 gpm and absolute vorticity (31025) is analyzed in dashed lines every 5 s21. FIG. 2. Skew T-log p diagram for Denver sounding at 1200 UTC 21 Jun 1993. Full wind barb is 5 m s21. FIG. 3. 500-mb observed... relative humidity and winds for 1200 UTC 21 Jun 1993 over innermost grid region shown in Fig. 5. Relative humidity is contoured every 10%, with full wind barb representing 5 m s21. Denver County is the smallest county near the center of the map. This work...

  19. Technical Sessions Parameterization of Convective Clouds, Mesoscale Convective Systems,

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over Our InstagramStructureProposedPAGESafety Tag:8,, 20153 To.T. J. KulpP. Daum

  20. Silicon Micromachined Dimensional Calibration Artifact for Mesoscale...

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

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

  1. A numerical simulation of slantwise convection: its structure and evolution

    E-Print Network [OSTI]

    Overpeck, Scott Allen

    2001-01-01T23:59:59.000Z

    convection), and could be a possible explanation for frontal rainbands. This study uses the Penn State/NCAR Mesoscale Model (MM5) as a diagnostic tool to simulate a slantwise convective case from the Genesis of Atlantic Lows Experiment (GALE, Dirks et al...

  2. Mesoscale Dynamics Spring Semester 2012

    E-Print Network [OSTI]

    Birner, Thomas

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

  3. 4, 54555514, 2004 Mesoscale modeling

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

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

  4. MESOSCALE DESCRIPTION OF DEFECTED MATERIALS

    E-Print Network [OSTI]

    Vinals, Jorge

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

  5. Mesoscale Dynamics Spring Semester 2014

    E-Print Network [OSTI]

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

  6. 7, 1043910465, 2007 Mesoscale inversion

    E-Print Network [OSTI]

    Boyer, Edmond

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

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

    E-Print Network [OSTI]

    Han, Sang-Ok

    1998-01-01T23:59:59.000Z

    On 2 June 1995, many supercede thunderstorms were graphics. observed in West Texas between Lubbock and Amarillo under the synoptic and mesoscale environment which was increasingly more supportive of severe convection. Of the storms, those which...

  8. A climatology of springtime convection systems over the Northwest Gulf of Mexico and adjacent coasts

    E-Print Network [OSTI]

    Hashem, Magda Sami

    1996-01-01T23:59:59.000Z

    A Springtime (March 15-June 15) climatology of Mesoscale Convective Systems (MCS) has been established on the basis of satellite imagery and radar reflectivities over the Northwest Gulf of Mexico and adjacent coastal areas during 1985...

  9. Mesoscale coupled ocean-atmosphere interaction

    E-Print Network [OSTI]

    Seo, Hyodae

    2007-01-01T23:59:59.000Z

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

  10. Mesoscale Coupled Ocean-Atmosphere Interaction

    E-Print Network [OSTI]

    Seo, Hyodae

    2007-01-01T23:59:59.000Z

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

  11. A transilient matrix for moist convection

    SciTech Connect (OSTI)

    Romps, D.; Kuang, Z.

    2011-08-15T23:59:59.000Z

    A method is introduced for diagnosing a transilient matrix for moist convection. This transilient matrix quantifies the nonlocal transport of air by convective eddies: for every height z, it gives the distribution of starting heights z{prime} for the eddies that arrive at z. In a cloud-resolving simulation of deep convection, the transilient matrix shows that two-thirds of the subcloud air convecting into the free troposphere originates from within 100 m of the surface. This finding clarifies which initial height to use when calculating convective available potential energy from soundings of the tropical troposphere.

  12. Mesoscale ocean dynamics modeling

    SciTech Connect (OSTI)

    mHolm, D.; Alber, M.; Bayly, B.; Camassa, R.; Choi, W.; Cockburn, B.; Jones, D.; Lifschitz, A.; Margolin, L.; Marsden, L.; Nadiga, B.; Poje, A.; Smolarkiewicz, P. [Los Alamos National Lab., NM (United States); Levermore, D. [Arizona Univ., Tucson, AZ (United States)

    1996-05-01T23:59:59.000Z

    This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The ocean is a very complex nonlinear system that exhibits turbulence on essentially all scales, multiple equilibria, and significant intrinsic variability. Modeling the ocean`s dynamics at mesoscales is of fundamental importance for long-time-scale climate predictions. A major goal of this project has been to coordinate, strengthen, and focus the efforts of applied mathematicians, computer scientists, computational physicists and engineers (at LANL and a consortium of Universities) in a joint effort addressing the issues in mesoscale ocean dynamics. The project combines expertise in the core competencies of high performance computing and theory of complex systems in a new way that has great potential for improving ocean models now running on the Connection Machines CM-200 and CM-5 and on the Cray T3D.

  13. Mesoscale hybrid calibration artifact

    SciTech Connect (OSTI)

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

    2010-09-07T23:59:59.000Z

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

  14. Radiative Heating of the ISCCP Upper Level Cloud Regimes and its Impact on the Large-scale Tropical Circulation

    SciTech Connect (OSTI)

    Li, Wei; Schumacher, Courtney; McFarlane, Sally A.

    2013-01-31T23:59:59.000Z

    Radiative heating profiles of the International Satellite Cloud Climatology Project (ISCCP) cloud regimes (or weather states) were estimated by matching ISCCP observations with radiative properties derived from cloud radar and lidar measurements from the Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) sites at Manus, Papua New Guinea, and Darwin, Australia. Focus was placed on the ISCCP cloud regimes containing the majority of upper level clouds in the tropics, i.e., mesoscale convective systems (MCSs), deep cumulonimbus with cirrus, mixed shallow and deep convection, and thin cirrus. At upper levels, these regimes have average maximum cloud occurrences ranging from 30% to 55% near 12 km with variations depending on the location and cloud regime. The resulting radiative heating profiles have maxima of approximately 1 K/day near 12 km, with equal heating contributions from the longwave and shortwave components. Upper level minima occur near 15 km, with the MCS regime showing the strongest cooling of 0.2 K/day and the thin cirrus showing no cooling. The gradient of upper level heating ranges from 0.2 to 0.4 K/(day?km), with the most convectively active regimes (i.e., MCSs and deep cumulonimbus with cirrus) having the largest gradient. When the above heating profiles were applied to the 25-year ISCCP data set, the tropics-wide average profile has a radiative heating maximum of 0.45Kday-1 near 250 hPa. Column-integrated radiative heating of upper level cloud accounts for about 20% of the latent heating estimated by the Tropical Rainfall Measuring Mission (TRMM) Precipitation Radar (PR). The ISCCP radiative heating of tropical upper level cloud only slightly modifies the response of an idealized primitive equation model forced with the tropics-wide TRMM PR latent heating, which suggests that the impact of upper level cloud is more important to large-scale tropical circulation variations because of convective feedbacks rather than direct forcing by the cloud radiative heating profiles. However, the height of the radiative heating maxima and gradient of the heating profiles are important to determine the sign and patterns of the horizontal circulation anomaly driven by radiative heating at upper levels.

  15. METR 4433, Mesoscale Meteorology Spring 2011

    E-Print Network [OSTI]

    Droegemeier, Kelvin K.

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

  16. ATS 641: Mesoscale Meteorology Spring 2014

    E-Print Network [OSTI]

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

  17. LMD Martian Mesoscale Model User Manual

    E-Print Network [OSTI]

    Spiga, Aymeric

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

  18. METR 4433, Mesoscale Meteorology Spring 2013

    E-Print Network [OSTI]

    Droegemeier, Kelvin K.

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

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

    E-Print Network [OSTI]

    Lopour, Beth Ann

    2009-01-01T23:59:59.000Z

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

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

    E-Print Network [OSTI]

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

    1993-01-01T23:59:59.000Z

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

  1. Evaluation of Cloud-resolving and Limited Area Model Intercomparison Simulations using TWP-ICE Observations. Part 1: Deep Convective Updraft Properties

    SciTech Connect (OSTI)

    Varble, A. C.; Zipser, Edward J.; Fridlind, Ann; Zhu, Ping; Ackerman, Andrew; Chaboureau, Jean-Pierre; Collis, Scott M.; Fan, Jiwen; Hill, Adrian; Shipway, Ben

    2014-12-27T23:59:59.000Z

    Ten 3D cloud-resolving model (CRM) simulations and four 3D limited area model (LAM) simulations of an intense mesoscale convective system observed on January 23-24, 2006 during the Tropical Warm Pool – International Cloud Experiment (TWP-ICE) are compared with each other and with observed radar reflectivity fields and dual-Doppler retrievals of vertical wind speeds in an attempt to explain published results showing a high bias in simulated convective radar reflectivity aloft. This high bias results from ice water content being large, which is a product of large, strong convective updrafts, although hydrometeor size distribution assumptions modulate the size of this bias. Snow reflectivity can exceed 40 dBZ in a two-moment scheme when a constant bulk density of 100 kg m-3 is used. Making snow mass more realistically proportional to area rather than volume should somewhat alleviate this problem. Graupel, unlike snow, produces high biased reflectivity in all simulations. This is associated with large amounts of liquid water above the freezing level in updraft cores. Peak vertical velocities in deep convective updrafts are greater than dual-Doppler retrieved values, especially in the upper troposphere. Freezing of large rainwater contents lofted above the freezing level in simulated updraft cores greatly contributes to these excessive upper tropospheric vertical velocities. Strong simulated updraft cores are nearly undiluted, with some showing supercell characteristics. Decreasing horizontal grid spacing from 900 meters to 100 meters weakens strong updrafts, but not enough to match observational retrievals. Therefore, overly intense simulated updrafts may partly be a product of interactions between convective dynamics, parameterized microphysics, and large-scale environmental biases that promote different convective modes and strengths than observed.

  2. Soft X-ray techniques to study mesoscale magnetism

    E-Print Network [OSTI]

    Kortright, Jeffrey B.

    2003-01-01T23:59:59.000Z

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

  3. Total lightning observations of severe convection over North Texas

    E-Print Network [OSTI]

    McKinney, Christopher Michael

    2009-05-15T23:59:59.000Z

    Density GSD Gridded Source Density LDAR Lightning Detection and Ranging MCS Mesoscale Convective System MSI Mesocyclone Strength Index MxFED Maximum Flash Extent Density MxFIDT Maximum Flash Initiation Density Total MxGSD Maximum Gridded Source.......................................................................................... 1 1.2 Background ....................................................................................... 4 1.3 Thesis Objectives and Hypothesis...................................................... 19 2. DATA AND METHODOLOGY...

  4. ATS 742 Tropical Meteorology-Fall 2013 Instructor: Professor Eric Maloney

    E-Print Network [OSTI]

    : Tropical budgets: heat, moisture, moist static energy, kinetic/potential energy Week 3: Weak tropical temperature gradients. Week 4: How convection heats the tropical atmosphere. Hot towers and other vertical heating modes Week 5: Modeling tropical precipitation with the moist static energy (MSE) budget Week 6

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

    E-Print Network [OSTI]

    Thompson, Anne

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

  6. Mesoscale Metallic Pyramids with Nanoscale Tips

    E-Print Network [OSTI]

    Odom, Teri W.

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

  7. MESOSCALE AVERAGING OF NUCLEATION AND GROWTH MODELS

    E-Print Network [OSTI]

    Burger, Martin

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

  8. TENURE-TRACK FACULTY POSITION Mesoscale Meteorology

    E-Print Network [OSTI]

    Birner, Thomas

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

  9. Mesoscale Model Development and the Meteorological Community

    E-Print Network [OSTI]

    Mass, Clifford F.

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

  10. Engineering mesoscale structures with distinct dynamical implications

    E-Print Network [OSTI]

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

  11. Acoustic Characterization of Mesoscale Objects

    SciTech Connect (OSTI)

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

    2007-03-13T23:59:59.000Z

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

  12. Posters Mesoscale Simulations of Convective Systems with Data Assimilation During

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's Possible forPortsmouth/Paducah Project Office PressPostdoctoraldecadal observations7197 Posters7

  13. Dynamics and generation mechanisms of mesoscale structures in tokamak edge plasmas

    SciTech Connect (OSTI)

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

    2008-05-15T23:59:59.000Z

    Intermittent convective-like plasma transport associated with mesoscale coherent structures extended along the magnetic field lines (''blobs'') is often dominant at the edge of tokamaks, stellarators, and linear devices. Blobs can travel a large distance toward the wall ({approx}10 cm and larger) and strongly enhance both edge plasma energy and particle transport and plasma-wall interactions. The dynamics of blobs and blob generation mechanisms are discussed in this paper.

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

    E-Print Network [OSTI]

    Iarova, D A

    2014-01-01T23:59:59.000Z

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

  15. HEAT TRANSFERS IN A DOUBLE SKIN ROOF VENTILATED BY NATURAL CONVECTION IN SUMMER TIME

    E-Print Network [OSTI]

    Boyer, Edmond

    1 HEAT TRANSFERS IN A DOUBLE SKIN ROOF VENTILATED BY NATURAL CONVECTION IN SUMMER TIME P. H and the sheet metal: This is ventilation by natural convection. The remaining conductive heat from the sheet or in tropical and arid countries. In this work, radiation, convection and conduction heat transfers

  16. Adjustment of the Remote Tropical Climate to El Nio Conditions BENJAMIN R. LINTNER* AND JOHN C. H. CHIANG

    E-Print Network [OSTI]

    Lintner, Benjamin Richard

    convective heating anomalies that in turn cause remote tropical changes through a suite of tele- connectedAdjustment of the Remote Tropical Climate to El Niño Conditions BENJAMIN R. LINTNER* AND JOHN C. H) ABSTRACT The adjustment of the tropical climate outside the Pacific (the "remote Tropics") to the abrupt

  17. High-Resolution Modeling to Assess Tropical Cyclone Activity in Future Climate Regimes

    SciTech Connect (OSTI)

    Lackmann, Gary

    2013-06-10T23:59:59.000Z

    Applied research is proposed with the following objectives: (i) to determine the most likely level of tropical cyclone intensity and frequency in future climate regimes, (ii) to provide a quantitative measure of uncertainty in these predictions, and (iii) to improve understanding of the linkage between tropical cyclones and the planetary-scale circulation. Current mesoscale weather forecasting models, such as the Weather Research and Forecasting (WRF) model, are capable of simulating the full intensity of tropical cyclones (TC) with realistic structures. However, in order to accurately represent both the primary and secondary circulations in these systems, model simulations must be configured with sufficient resolution to explicitly represent convection (omitting the convective parameterization scheme). Most previous numerical studies of TC activity at seasonal and longer time scales have not utilized such explicit convection (EC) model runs. Here, we propose to employ the moving nest capability of WRF to optimally represent TC activity on a seasonal scale using a downscaling approach. The statistical results of a suite of these high-resolution TC simulations will yield a realistic representation of TC intensity on a seasonal basis, while at the same time allowing analysis of the feedback that TCs exert on the larger-scale climate system. Experiments will be driven with analyzed lateral boundary conditions for several recent Atlantic seasons, spanning a range of activity levels and TC track patterns. Results of the ensemble of WRF simulations will then be compared to analyzed TC data in order to determine the extent to which this modeling setup can reproduce recent levels of TC activity. Next, the boundary conditions (sea-surface temperature, tropopause height, and thermal/moisture profiles) from the recent seasons will be altered in a manner consistent with various future GCM/RCM scenarios, but that preserves the large-scale shear and incipient disturbance activity. This will allow (i) a direct comparison of future TC activity that could be expected for an active or inactive season in an altered climate regime, and (ii) a measure of the level of uncertainty and variability in TC activity resulting from different carbon emission scenarios.

  18. Dynamic Filtering and Mining Triggers in Mesoscale Meteorology Forecasting

    E-Print Network [OSTI]

    Plale, Beth

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

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

    E-Print Network [OSTI]

    Washington at Seattle, University of

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

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

    E-Print Network [OSTI]

    Sethna, James P.

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

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

    E-Print Network [OSTI]

    Rovegno, Peter

    2012-01-01T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Michalakes, John

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

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

    E-Print Network [OSTI]

    Putrasahan, Dian Ariyani

    2012-01-01T23:59:59.000Z

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

  4. CHARACTERIZATION OF CLOUDS IN TITAN'S TROPICAL ATMOSPHERE

    SciTech Connect (OSTI)

    Griffith, Caitlin A.; Penteado, Paulo [Department of Planetary Sciences, University of Arizona, Tucson, AZ 85719 (United States); Rodriguez, Sebastien [Laboratoire AIM, Universite Paris 7/CNRS/CEA-Saclay, DSM/IRFU/SAp (France); Le Mouelic, Stephane [Laboratoire de Planetologie et Geodynamique, CNRS, UMR-6112, Universite de Nantes, 44000 Nantes (France); Baines, Kevin H.; Buratti, Bonnie; Sotin, Christophe [Jet Propulsion Laboratory, Pasadena, CA 91109 (United States); Clark, Roger [U.S. Geological Survey, Denver, CO 80225 (United States); Nicholson, Phil [Department of Astronomy, Cornell University, Ithaca, NY (United States); Jaumann, Ralf [Institute of Planetary Exploration, Deutsche Zentrum, fuer Luft- und Raumfahrt (Germany)

    2009-09-10T23:59:59.000Z

    Images of Titan's clouds, possible over the past 10 years, indicate primarily discrete convective methane clouds near the south and north poles and an immense stratiform cloud, likely composed of ethane, around the north pole. Here we present spectral images from Cassini's Visual Mapping Infrared Spectrometer that reveal the increasing presence of clouds in Titan's tropical atmosphere. Radiative transfer analyses indicate similarities between summer polar and tropical methane clouds. Like their southern counterparts, tropical clouds consist of particles exceeding 5 {mu}m. They display discrete structures suggestive of convective cumuli. They prevail at a specific latitude band between 8 deg. - 20 deg. S, indicative of a circulation origin and the beginning of a circulation turnover. Yet, unlike the high latitude clouds that often reach 45 km altitude, these discrete tropical clouds, so far, remain capped to altitudes below 26 km. Such low convective clouds are consistent with the highly stable atmospheric conditions measured at the Huygens landing site. Their characteristics suggest that Titan's tropical atmosphere has a dry climate unlike the south polar atmosphere, and despite the numerous washes that carve the tropical landscape.

  5. Ecospace: Prediction of Mesoscale Spatial Patterns in Trophic

    E-Print Network [OSTI]

    Pauly, Daniel

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

  6. New Mesoscale Multimodal Imaging of Cellular Communication Between...

    Office of Science (SC) Website

    New Mesoscale Multimodal Imaging Bioimaging Technology Bioimaging Technology Home About Research Small Worlds New Mesoscale Multimodal Imaging Adaptive Biosystems Imaging Systems...

  7. Convection towers

    DOE Patents [OSTI]

    Prueitt, M.L.

    1996-01-16T23:59:59.000Z

    Convection towers which are capable of cleaning the pollution from large quantities of air, of generating electricity, and of producing fresh water utilize the evaporation of water sprayed into the towers to create strong airflows and to remove pollution from the air. Turbines in tunnels at the skirt section of the towers generate electricity, and condensers produce fresh water. 6 figs.

  8. Convection towers

    DOE Patents [OSTI]

    Prueitt, Melvin L. (Los Alamos, NM)

    1994-01-01T23:59:59.000Z

    Convection towers which are capable of cleaning the pollution from large quantities of air and of generating electricity utilize the evaporation of water sprayed into the towers to create strong airflows and to remove pollution from the air. Turbines in tunnels at the skirt section of the towers generate electricity. Other embodiments may also provide fresh water, and operate in an updraft mode.

  9. Convection towers

    DOE Patents [OSTI]

    Prueitt, Melvin L. (Los Alamos, NM)

    1996-01-01T23:59:59.000Z

    Convection towers which are capable of cleaning the pollution from large quantities of air, of generating electricity, and of producing fresh water utilize the evaporation of water sprayed into the towers to create strong airflows and to remove pollution from the air. Turbines in tunnels at the skirt section of the towers generate electricity, and condensers produce fresh water.

  10. Convection towers

    DOE Patents [OSTI]

    Prueitt, Melvin L. (Los Alamos, NM)

    1995-01-01T23:59:59.000Z

    Convection towers which are capable of cleaning the pollution from large quantities of air, of generating electricity, and of producing fresh water utilize the evaporation of water sprayed into the towers to create strong airflows and to remove pollution from the air. Turbines in tunnels at the skirt section of the towers generate electricity, and condensers produce fresh water.

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

    E-Print Network [OSTI]

    Guglielmi, Y.

    2008-01-01T23:59:59.000Z

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

  12. Convection towers

    DOE Patents [OSTI]

    Prueitt, M.L.

    1994-02-08T23:59:59.000Z

    Convection towers which are capable of cleaning the pollution from large quantities of air and of generating electricity utilize the evaporation of water sprayed into the towers to create strong airflows and to remove pollution from the air. Turbines in tunnels at the skirt section of the towers generate electricity. Other embodiments may also provide fresh water, and operate in an updraft mode. 5 figures.

  13. Molecule-Mimetic Chemistry and Mesoscale Self-Assembly

    E-Print Network [OSTI]

    Prentiss, Mara

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

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

    E-Print Network [OSTI]

    Boyer, Edmond

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

  15. Multiphase Modeling of Flow, Transport, and Biodegradation in a Mesoscale Landfill Bioreactor

    E-Print Network [OSTI]

    Oldenburg, Curtis M.; Borglin, Sharon E.; Hazen, Terry C.

    2002-01-01T23:59:59.000Z

    boundary conditions for the mesoscale landfill bioreactor. (and Biodegradation in a Mesoscale Landfill Bioreactor Curtisapplied it to our own mesoscale laboratory aerobic landfill

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

    E-Print Network [OSTI]

    Magid, K. R.

    2009-01-01T23:59:59.000Z

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

  17. Analytical mesoscale modeling of aeolian sand transport

    E-Print Network [OSTI]

    Marc Lämmel; Anne Meiwald; Klaus Kroy

    2014-05-03T23:59:59.000Z

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

  18. MESOSCALE SIMULATIONS OF POWDER COMPACTION

    SciTech Connect (OSTI)

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

    2009-12-28T23:59:59.000Z

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

  19. Postulated Mesoscale Quantum of Internal Friction Hysteresis

    E-Print Network [OSTI]

    Randall D. Peters

    2004-05-27T23:59:59.000Z

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

  20. Convective heater

    DOE Patents [OSTI]

    Thorogood, Robert M. (Macungie, PA)

    1986-01-01T23:59:59.000Z

    A convective heater for heating fluids such as a coal slurry is constructed of a tube circuit arrangement which obtains an optimum temperature distribution to give a relatively constant slurry film temperature. The heater is constructed to divide the heating gas flow into two equal paths and the tube circuit for the slurry is arranged to provide a mixed flow configuration whereby the slurry passes through the two heating gas paths in successive co-current, counter-current and co-current flow relative to the heating gas flow. This arrangement permits the utilization of minimum surface area for a given maximum film temperature of the slurry consistent with the prevention of coke formation.

  1. Convective heater

    DOE Patents [OSTI]

    Thorogood, R.M.

    1983-12-27T23:59:59.000Z

    A convective heater for heating fluids such as a coal slurry is constructed of a tube circuit arrangement which obtains an optimum temperature distribution to give a relatively constant slurry film temperature. The heater is constructed to divide the heating gas flow into two equal paths and the tube circuit for the slurry is arranged to provide a mixed flow configuration whereby the slurry passes through the two heating gas paths in successive co-current, counter-current and co-current flow relative to the heating gas flow. This arrangement permits the utilization of minimum surface area for a given maximum film temperature of the slurry consistent with the prevention of coke formation. 14 figs.

  2. Convective heater

    DOE Patents [OSTI]

    Thorogood, Robert M. (Macungie, PA)

    1983-01-01T23:59:59.000Z

    A convective heater for heating fluids such as a coal slurry is constructed of a tube circuit arrangement which obtains an optimum temperature distribution to give a relatively constant slurry film temperature. The heater is constructed to divide the heating gas flow into two equal paths and the tube circuit for the slurry is arranged to provide a mixed flow configuration whereby the slurry passes through the two heating gas paths in successive co-current, counter-current and co-current flow relative to the heating gas flow. This arrangement permits the utilization of minimum surface area for a given maximum film temperature of the slurry consistent with the prevention of coke formation.

  3. The Roles of an Expanding Wind Field and Inertial Stability in Tropical Cyclone Secondary Eyewall Formation

    E-Print Network [OSTI]

    Kossin, James P.

    of Mesoscale Severe Weather (MOE), Department of Atmospheric Sciences, Nanjing University, Nanjing, China and Forecasting Model (WRF) is used to simulate secondary eyewall formation (SEF) in a tropical cyclone (TC) on the b plane. The simulated SEF process is accompanied by an outward expansion of kinetic energy

  4. The Sensitivity of Intraseasonal Variability in the NCAR CCM3 to Changes in Convective Parameterization

    E-Print Network [OSTI]

    Maloney, Eric

    The Sensitivity of Intraseasonal Variability in the NCAR CCM3 to Changes in Convective@atmos.washington.edu. #12;1 Abstract The NCAR CCM3.6 simulation of tropical intraseasonal variability in zonal winds and pre- cipitation can be improved by implementing the McRAS convection scheme of Sud and Walker. The default CCM3

  5. Analysis of the Tropical Tropopause Layer Cirrus in CALIPSO and MLS Data - A Water Perspective

    E-Print Network [OSTI]

    Wang, Tao

    2012-07-16T23:59:59.000Z

    Two mechanisms appear to be primarily responsible for the formation of cirrus clouds in Tropical Tropopause Layer (TTL): detrainment from deep convective anvils and in situ initiation. Here we propose to identify TTL cirrus clouds by analyzing...

  6. THE NOAA HAZARDOUS WEATHER TESTBED: COLLABORATIVE TESTING OF ENSEMBLE AND CONVECTION-ALLOWING WRF MODELS AND SUBSEQUENT

    E-Print Network [OSTI]

    Xue, Ming

    THE NOAA HAZARDOUS WEATHER TESTBED: COLLABORATIVE TESTING OF ENSEMBLE AND CONVECTION-ALLOWING WRF NOAA's Hazardous Weather Testbed (HWT) is a joint facility managed by the National Severe Storms and technologies into advances in forecasting and warning for hazardous mesoscale weather events throughout

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

    E-Print Network [OSTI]

    Smith, Ryan N.

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

  8. Mesoscale Simulations of Power Compaction

    SciTech Connect (OSTI)

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

    2009-08-06T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Raghavan, Srinivasa

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

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

    E-Print Network [OSTI]

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

  11. Simulation and characterization of the Adriatic Sea mesoscale variability

    E-Print Network [OSTI]

    Cushman-Roisin, Benoit

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

  12. GLOBAL PATTERN OF MESOSCALE VARIABILITY IN SEA SURFACE HEIGHT

    E-Print Network [OSTI]

    Kaplan, Alexey

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

  13. Remotely sensed mesoscale oceanography and the distribution of Illex argentinus

    E-Print Network [OSTI]

    Pierce, Graham

    Remotely sensed mesoscale oceanography and the distribution of Illex argentinus in the South consider the in¯uence of mesoscale oceanographic processes around the Falkland Islands (Islas Malvinas remotely sensed satellite images were used as an indicator of mesoscale oceanographic activity and compared

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

    E-Print Network [OSTI]

    Grujicic, Mica

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

  15. AN URBAN SURFACE EXCHANGE PARAMETERISATION FOR MESOSCALE MODELS

    E-Print Network [OSTI]

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

  16. A Mesoscale Diffusion Model in Population Genetics with

    E-Print Network [OSTI]

    O'Leary, Michael

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

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

    E-Print Network [OSTI]

    Santos, Juan

    Numerical Simulation in Applied Geophysics. From the Mesoscale to the Macroscale Juan E. Santos Numerical Simulation in Applied Geophysics. From the Mesoscale to the Macroscale ­ p. #12;Introduction. I layering, fractures and craks at the mesoscale (on the order of centimeters) are common in the earth

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

    E-Print Network [OSTI]

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

  19. Report on the use of stability parameters and mesoscale

    E-Print Network [OSTI]

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

  20. Identification of a mesoscale model with multiscale experimental observations

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

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

  1. Computational upscaling of inertia effects from porescale to mesoscale

    E-Print Network [OSTI]

    Peszynska, Malgorzata

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

  2. Hyperparameter estimation for uncertainty quantification in mesoscale carbon dioxide inversions

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Hyperparameter estimation for uncertainty quantification in mesoscale carbon dioxide inversions-validation (GCV) and x2 test are compared for the first time under a realistic setting in a mesoscale CO2 estimation, uncertainty quantification, mesoscale carbon dioxide inversions 1. Introduction The atmosphere

  3. Mesoscale morphologies in polymer thin films.

    SciTech Connect (OSTI)

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

    2011-06-01T23:59:59.000Z

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

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

    E-Print Network [OSTI]

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

  5. Particle-Based Mesoscale Hydrodynamic Techniques

    E-Print Network [OSTI]

    Hiroshi Noguchi; Norio Kikuchi; Gerhard Gompper

    2006-10-31T23:59:59.000Z

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

  6. SURFACE TENSION DRIVEN CONVECTION

    E-Print Network [OSTI]

    Wang, Shouhong

    SURFACE TENSION DRIVEN CONVECTION DIJKSTRA, SENGUL, WANG INTRODUCTION LINEAR THEORY MAIN THEOREMS CONCLUDING REMARKS DYNAMIC TRANSITIONS OF SURFACE TENSION DRIVEN CONVECTION H.Dijkstra T. Sengul S. Wang #12;SURFACE TENSION DRIVEN CONVECTION DIJKSTRA, SENGUL, WANG INTRODUCTION LINEAR THEORY MAIN THEOREMS

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

    SciTech Connect (OSTI)

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

    2013-10-01T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

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

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

    E-Print Network [OSTI]

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

    2004-01-01T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Miami, University of

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

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

    E-Print Network [OSTI]

    Lisal, Martin

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

  12. From deterministic to stochastic, from mesoscale to macroscopic

    E-Print Network [OSTI]

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

  13. ARM Convective Available Potential Energy (CAPE), Convective Inhibition (CIN) Product

    SciTech Connect (OSTI)

    Jensen, Michael

    2014-04-10T23:59:59.000Z

    ARM soundings are used to determine Convective Available Potential Energy (CAPE), Convective Inhibition (CIN) and associated properties, using the following relationships;

  14. ARM Convective Available Potential Energy (CAPE), Convective Inhibition (CIN) Product

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Jensen, Michael

    ARM soundings are used to determine Convective Available Potential Energy (CAPE), Convective Inhibition (CIN) and associated properties, using the following relationships;

  15. Mesoscale harmonic analysis of homogenous dislocation nucleation

    E-Print Network [OSTI]

    Asad Hasan; Craig E. Maloney

    2012-05-08T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Asher, Sanford A.

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

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

    E-Print Network [OSTI]

    Schlick, Tamar

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

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

    E-Print Network [OSTI]

    Nielsen, Karina J.

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

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

    E-Print Network [OSTI]

    Sethna, James P.

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

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

    E-Print Network [OSTI]

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

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

    E-Print Network [OSTI]

    Lisal, Martin

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

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

    E-Print Network [OSTI]

    Elliott, James

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

  3. Impact of Secondary Eyewall Heating on Tropical Cyclone Intensity Change* XIAQIONG ZHOU, BIN WANG, XUYANG GE, AND TIM LI

    E-Print Network [OSTI]

    Wang, Bin

    Impact of Secondary Eyewall Heating on Tropical Cyclone Intensity Change* XIAQIONG ZHOU, BIN WANG is to explore the factors that might influence the intensity change of tropical cyclones (TCs) associated. Introduction Concentric eyewalls usually refer to two or more quasi-circular eyewalls separated by a convective

  4. Rotational and divergent kinetic energy in the mesoscale model ALADIN

    E-Print Network [OSTI]

    Zagar, Nedjeljka

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

  5. Parameterizing deep convection using the assumed probability density function method

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

    Storer, R. L.; Griffin, B. M.; Höft, J.; Weber, J. K.; Raut, E.; Larson, V. E.; Wang, M.; Rasch, P. J.

    2015-01-01T23:59:59.000Z

    Due to their coarse horizontal resolution, present-day climate models must parameterize deep convection. This paper presents single-column simulations of deep convection using a probability density function (PDF) parameterization. The PDF parameterization predicts the PDF of subgrid variability of turbulence, clouds, and hydrometeors. That variability is interfaced to a prognostic microphysics scheme using a Monte Carlo sampling method.The PDF parameterization is used to simulate tropical deep convection, the transition from shallow to deep convection over land, and midlatitude deep convection. These parameterized single-column simulations are compared with 3-D reference simulations. The agreement is satisfactory except when the convective forcing is weak.more »The same PDF parameterization is also used to simulate shallow cumulus and stratocumulus layers. The PDF method is sufficiently general to adequately simulate these five deep, shallow, and stratiform cloud cases with a single equation set. This raises hopes that it may be possible in the future, with further refinements at coarse time step and grid spacing, to parameterize all cloud types in a large-scale model in a unified way.« less

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

    E-Print Network [OSTI]

    Daniels, Megan Hanako

    2010-01-01T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Tandon, Amit

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

  8. Tropical Cyclone Intensification from Asymmetric Convection: Energetics and Efficiency

    E-Print Network [OSTI]

    Nolan, David S.

    and some new methods of analysis. The model equations have been changed to be more consistent and available potential energies are presented for both asymmetric and symmetric motions, and these are used to quantify the flow of energy from localized, asymmetric heat sources to kinetic energy of the wind field

  9. ARM - Field Campaign - Year of Tropical Convection (YOTC)

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006Datastreamstwrcam40m DocumentationJanuary 9, 2009 [Events, Feature StoriesgovCampaignsSurface Heat

  10. Limiting Factors for Convective Cloud Top Height in the Tropics

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn12electron 9 5Let us countLighting SignLiisa

  11. Patterns of Convection in the Tropical Western Pacific

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's Possible for RenewableSpeedingBiomassPPPO WebsitePalms Village95-1999) HeegerPatrick

  12. Properties of tropical convection observed by ARM millimeter-radars

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's Possible forPortsmouth/Paducah47,193.70 HgPromising Magnesium Battery Research Weekly

  13. Mesoscale Quantization and Self-Organized Stability

    E-Print Network [OSTI]

    Randall D. Peters

    2005-06-16T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

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

    2004-09-24T23:59:59.000Z

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

  15. Analysis of azimuthal mode dynamics of mesoscale eddies

    E-Print Network [OSTI]

    McCalpin, John David

    1984-01-01T23:59:59.000Z

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

  16. Mesoscale Systems: weather associated with circulation systems of horizontal scales of 5 to 1,000 km

    E-Print Network [OSTI]

    Weber, Rodney

    Mesoscale Systems: weather associated with circulation systems of horizontal scales of 5 to 1 faster at night #12;Dispersion in Mesoscale Systems Mesoscale systems can have large effects on pollution

  17. Convective Cloud Lifecycles Lunchtime seminar

    E-Print Network [OSTI]

    Plant, Robert

    Convective Cloud Lifecycles Lunchtime seminar 19th May 2009 Bob Plant Department of Meteorology, University of Reading, UK #12;Introduction Obtain life cycle statistics for clouds in CRM simulations Why Conclusions Convective Cloud Lifecycles ­ p.1/3 #12;Why bother? Convective Cloud Lifecycles ­ p.2/3 #12;Some

  18. Tropical Underdevelopment Jeffrey D. Sachs

    E-Print Network [OSTI]

    of mobilizing energy resources in tropical economies is emphasized as another significant contributor measure of economic development. Tropical and landlocked regions, by contrast ­ such as Bolivia, Chad

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

    E-Print Network [OSTI]

    Boyer, Edmond

    2003-01-01T23:59:59.000Z

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

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

    E-Print Network [OSTI]

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

  1. 1234 VOLUME 42J O U R N A L O F A P P L I E D M E T E O R O L O G Y Radiative and Microphysical Characteristics of Deep Convective Systems in the

    E-Print Network [OSTI]

    precipitation radar and Geostationary Meteorological Satellite infrared radiometer measurements are used%. In cases in which the convective available potential energy (CAPE) is large, deep convective clouds roles in producing the high albedos of tropical anvil clouds. A comparison of the radiative heating

  2. Development of Ensemble Neural Network Convection Parameterizations for Climate Models

    SciTech Connect (OSTI)

    Fox-Rabinovitz, M. S.; Krasnopolsky, V. M.

    2012-05-02T23:59:59.000Z

    The novel neural network (NN) approach has been formulated and used for development of a NN ensemble stochastic convection parametrization for climate models. This fast parametrization is built based on data from Cloud Resolving Model (CRM) simulations initialized with and forced by TOGA-COARE data. The SAM (System for Atmospheric Modeling), developed by D. Randall, M. Khairoutdinov, and their collaborators, has been used for CRM simulations. The observational data are also used for validation of model simulations. The SAM-simulated data have been averaged and projected onto the GCM space of atmospheric states to implicitly define a stochastic convection parametrization. This parametrization is emulated using an ensemble of NNs. An ensemble of NNs with different NN parameters has been trained and tested. The inherent uncertainty of the stochastic convection parametrization derived in such a way is estimated. Due to these inherent uncertainties, NN ensemble is used to constitute a stochastic NN convection parametrization. The developed NN convection parametrization have been validated in a diagnostic CAM (CAM-NN) run vs. the control CAM run. Actually, CAM inputs have been used, at every time step of the control/original CAM integration, for parallel calculations of the NN convection parametrization (CAM-NN) to produce its outputs as a diagnostic byproduct. Total precipitation (P) and cloudiness (CLD) time series, diurnal cycles, and P and CLD distributions for the large Tropical Pacific Ocean for the parallel CAM-NN and CAM runs show similarity and consistency with the NCEP reanalysis. The P and CLD distributions for the tropical area for the parallel runs have been analyzed first for the TOGA-COARE boreal winter season (November 1992 through February 1993) and then for the winter seasons of the follow-up parallel decadal simulations. The obtained results are encouraging and practically meaningful. They show the validity of the NN approach. This constitutes an important practical conclusion of the study: the obtained results on NN ensembles as a stochastic physics parametrization show a realistic possibility of development of NN convection parametrization for climate (and NWP) models based on learning cloud physics from CRM/SAM simulated data.

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

    E-Print Network [OSTI]

    Richner, Heinz

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

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

    E-Print Network [OSTI]

    Schlick, Tamar

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

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

    E-Print Network [OSTI]

    Lin, Zhiqun

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

  6. Course MA59800: Numerical Simulation in Applied Geophysics. From the Mesoscale to the Macroscale.

    E-Print Network [OSTI]

    Santos, Juan

    Course MA59800: Numerical Simulation in Applied Geophysics. From the Mesoscale to the Macroscale matrix properties, fine layering, frac- tures and craks at the mesoscale (on the order of centimeters

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

    E-Print Network [OSTI]

    Santos, Juan

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

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

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

    Mesoscale Origin of the Enhanced Cycling-Stability of the Si-Conductive Polymer Anode for Li-ion Batteries. Mesoscale Origin of the Enhanced Cycling-Stability of the Si-Conductive...

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

    E-Print Network [OSTI]

    Sastry, Ann Marie

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

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

    E-Print Network [OSTI]

    Pilon, Laurent

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

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

    E-Print Network [OSTI]

    Goddard III, William A.

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

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

    E-Print Network [OSTI]

    Geissler, Phillip

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

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

    E-Print Network [OSTI]

    Elliott, James

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

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

    E-Print Network [OSTI]

    Lisbon, University of

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

  15. MPMM: A Massively Parallel Mesoscale Model

    SciTech Connect (OSTI)

    Foster, I.; Michalakes, J.

    1992-12-31T23:59:59.000Z

    Static domain decomposition is a technique that provides a quick path to porting atmospheric models on distributed memory parallel computers. However, parallel inefficiencies in the form of load imbalances and ill-tuned communication are difficult to correct without complicated and explicit recoding. Reconfiguring the code to run on larger or smaller numbers of processors may require recompiling. Modularity and machine independence may also suffer. If full advantage is to be taken of Massively Parallel Processing (MPP) technology, tools and techniques that allow for dynamic performance tuning and reconfiguration are required. Program Composition Notation (PCN) is a language and run-time system for expressing parallel programs developed at Argonne and at the California Institute of Technology. It provides an intermediate layer between the application program and the physical processors of a computer. It allows the model to be statically decomposed over a virtual machine, but this virtual machine can be mapped and remapped dynamically over the physical computer. Programs are portable to as many machines as PCN itself, modularity is easily preserved, and communication tuning for a particular computer is encapsulated within the PCN run-time system. In this paper we report on a project at Argonne National Laboratory to parallelize the Penn State/NCAR Mesoscale Model version 5 using a fine grain decomposition dynamically mapped and managed under PCN.

  16. Meso-scale turbulence in living fluids

    E-Print Network [OSTI]

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

    2012-08-21T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Maine, University of

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

  18. Wind ringing of the ocean in presence of mesoscale eddies P. Klein and G. Lapeyre

    E-Print Network [OSTI]

    Lapeyre, Guillaume

    Wind ringing of the ocean in presence of mesoscale eddies P. Klein and G. Lapeyre Laboratoire de scales related to oceanic mesoscale eddies. Results show that a turbulent eddy field does not affect Oceanography: Physical: Eddies and mesoscale processes; 4572 Oceanography: Physical: Upper ocean processes

  19. New Efficient Sparse SpaceTime Algorithms for Superparameterization on Mesoscales

    E-Print Network [OSTI]

    Xing, Yulong

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

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

    E-Print Network [OSTI]

    Cai, Wei

    1995-01-01T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Miami, University of

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

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

    E-Print Network [OSTI]

    Tandon, Amit

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

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

    E-Print Network [OSTI]

    Miami, University of

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

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

    E-Print Network [OSTI]

    Plale, Beth

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

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

    E-Print Network [OSTI]

    Rooker, Jay R.

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

  6. A SCALABLE FULLY IMPLICIT COMPRESSIBLE EULER SOLVER FOR MESOSCALE NONHYDROSTATIC SIMULATION OF

    E-Print Network [OSTI]

    Cai, Xiao-Chuan

    A SCALABLE FULLY IMPLICIT COMPRESSIBLE EULER SOLVER FOR MESOSCALE NONHYDROSTATIC SIMULATION for the mesoscale nonhydrostatic simulation of atmospheric flows governed by the compressible Euler equations is of interest as in mesoscale and cloud-resolving atmospheric simulations, fast and efficient solution

  7. Author , Short title EFFECTS OF MESOSCALE TEXTURE ON APPARENT SURFACE GLOSS

    E-Print Network [OSTI]

    Ferwerda, James A.

    Author , Short title 1 EFFECTS OF MESOSCALE TEXTURE ON APPARENT SURFACE GLOSS James A. Ferwerda to it. We first measure both the microscale reflectance properties and mesoscale texture of flat, latex these images as stimuli in perceptual experiments to systematically study how surface mesoscale properties

  8. Persistence of iron limitation in the western subarctic Pacific SEEDS II mesoscale fertilization experiment

    E-Print Network [OSTI]

    Cochlan, William P.

    Persistence of iron limitation in the western subarctic Pacific SEEDS II mesoscale fertilization t The cumulative evidence from more than a dozen mesoscale iron-enrichment studies in high nitrate low chlorophyll diatoms, vary greatly among these mesoscale experiments even though similar amounts of iron were added

  9. Spatio-temporal segmentation of mesoscale ocean surface dynamics using satellite data

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Spatio-temporal segmentation of mesoscale ocean surface dynamics using satellite data Pierre Tandeo Temperature (SST) provide a wealth of information about ocean circulation, espe- cially mesoscale ocean an observation-driven framework, we investigate the extent to which mesoscale ocean dynamics may be decomposed

  10. Development of a Piezoelectrically-Actuated Mesoscale Robot Quadruped Michael Goldfarb, Michael Gogola, Gregory Fischer

    E-Print Network [OSTI]

    Development of a Piezoelectrically-Actuated Mesoscale Robot Quadruped Michael Goldfarb, Michael approach that offers a high locomotive efficiency, and is therefore well suited to mesoscale robot design actuated mesoscale robot quadruped. The design described utilizes a lightly damped skeletal structure

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

    E-Print Network [OSTI]

    Howat, Ian M.

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

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

    E-Print Network [OSTI]

    Fox-Kemper, Baylor

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

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

    E-Print Network [OSTI]

    Mass, Clifford F.

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

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

    E-Print Network [OSTI]

    Cushman-Roisin, Benoit

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

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

    E-Print Network [OSTI]

    Raman, Sethu

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

  16. Studies on non-premixed flame streets in a mesoscale channel

    E-Print Network [OSTI]

    Ju, Yiguang

    Studies on non-premixed flame streets in a mesoscale channel Bo Xu *, Yiguang Ju Department of channel width, wall temperature, and flow rate on the dynamics of non-premix flames in a mesoscale The Combustion Institute. Published by Elsevier Inc. All rights reserved. Keywords: Mesoscale combustion; Non

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

    E-Print Network [OSTI]

    Moelders, Nicole

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

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

    E-Print Network [OSTI]

    Spiga, Aymeric

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

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

    E-Print Network [OSTI]

    Prentiss, Mara

    Mesoscale Self-Assembly of Hexagonal Plates Using Lateral Capillary Forces: Synthesis Using examines self-assembly in a quasi-two-dimensional, mesoscale system. The system studied here involves-assembly from the molecular to the mesoscale, (ii) the demonstration of a system in which small objects can

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

    E-Print Network [OSTI]

    Qiu, Bo

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

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

    E-Print Network [OSTI]

    Levi, Anthony F. J.

    2011-01-01T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Zhou, Quanlin

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

  3. Mesoscale distribution of zooplankton biomass in the northeast Atlantic Ocean determined with an Optical Plankton Counter

    E-Print Network [OSTI]

    Mesoscale distribution of zooplankton biomass in the northeast Atlantic Ocean determined Available online 2 June 2009 Keywords: Zooplankton Biomass Size distribution Mesoscale eddies Optical plankton counter Pelagic environment Northeast Atlantic Ocean a b s t r a c t We examined the mesoscale

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

    E-Print Network [OSTI]

    Niyogi, Dev

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

  5. Draft Chapter from Mesoscale Dynamic Meteorology By Prof. Yu-lang Lin, North Carolina State University

    E-Print Network [OSTI]

    Droegemeier, Kelvin K.

    1 Draft Chapter from Mesoscale Dynamic Meteorology By Prof. Yu-lang Lin, North Carolina State University Chapter 1 Overview 1.1 Introduction The so-called mesometeorology or mesoscale meteorology as mesoscale phenomena by others (e.g. Orlanski 1975; Thunis and Bornstein 1996). Therefore, a more precise

  6. Mesoscale Simulation of Grain David Kinderlehrer, Jeehyun Lee, Irene Livshits and Shlomo Ta'asan

    E-Print Network [OSTI]

    Mesoscale Simulation of Grain Growth David Kinderlehrer, Jeehyun Lee, Irene Livshits and Shlomo Ta'asan WILEY-VCH Verlag Berlin GmbH September 4, 2003 #12;2 0.1 Introduction The mesoscale simulation of grain of the statistics it provides, we are led to the companion issue of coarse graining in mesoscale simulations. We

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

    E-Print Network [OSTI]

    Hunt, Julian

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

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

    E-Print Network [OSTI]

    Pielke, Roger A.

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

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

    E-Print Network [OSTI]

    Fridlind, Ann

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

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

    E-Print Network [OSTI]

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

  11. Mesoscale transport properties induced by near critical resistive pressure-gradient-driven turbulence in toroidal geometry

    E-Print Network [OSTI]

    Martín-Solís, José Ramón

    Mesoscale transport properties induced by near critical resistive pressure diffusive equation for mesoscale tracer-particle transport. The indices of the fractional derivates a mesoscale regime. That is, for time scales above the fluctuation scales reaching to the trans- port scales

  12. Mesoscale energetics and ows induced by sea-land and mountain-valley contrasts

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Mesoscale energetics and ¯ows induced by sea-land and mountain-valley contrasts S. Federico1 , G. A in determining the development of thermally forced mesoscale circula- tions (TFMCs) over a mountainous peninsula dynamics (climatology; mesoscale meteorology) 1 Introduction In the early hours of the morning the sun

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

    E-Print Network [OSTI]

    Fischlin, Andreas

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

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

    E-Print Network [OSTI]

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

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

    E-Print Network [OSTI]

    Menon, Govind

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

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

    E-Print Network [OSTI]

    Peszynska, Malgorzata

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

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

    E-Print Network [OSTI]

    Hamburg,.Universität

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

  18. Segmentation of mesoscale ocean surface dynamics using satellite SST and SSH observations

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 Segmentation of mesoscale ocean surface dynamics using satellite SST and SSH observations Pierre about ocean circulation, espe- cially mesoscale ocean dynamics which may involve strong spatio- temporal to which mesoscale ocean dynamics may be decomposed into a mixture of dynamical modes, characterized

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

    E-Print Network [OSTI]

    Generation of strong mesoscale eddies by weak ocean gyres by Michael A. Spall1 ABSTRACT The generation of strong mesoscale variability through instability of the large-scale circulation in the interior with the scaling theory. 1. Introduction It is now well recognized that the kinetic energy of the mesoscale

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

    E-Print Network [OSTI]

    Belykh, Igor

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

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

    E-Print Network [OSTI]

    Bergen, Universitetet i

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

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

    E-Print Network [OSTI]

    Qiu, Bo

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

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

    E-Print Network [OSTI]

    Niyogi, Dev

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

  4. Mesoscale symmetries explain dynamical equivalence of food webs

    E-Print Network [OSTI]

    Aufderheide, Helge; Gross, Thilo

    2012-01-01T23:59:59.000Z

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

  5. CIGUATERA: TROPICAL FISH POISONING

    E-Print Network [OSTI]

    CIGUATERA: TROPICAL FISH POISONING Marine Biological I · ·' iw« L I B R >*· ** Y JUL 3 -1350 WOODS POISONING By William Arcisz, Bacteriologist, Formerly with the Fishery Research Laboratory Branch in which Fish Poisoning is Prevalento........... 3 Symptoms of Ciguatera ...... 00

  6. Eddy heat fluxes at Drake Passage due to mesoscale motions

    E-Print Network [OSTI]

    Rojas Recabal, Ricardo Luis

    1982-01-01T23:59:59.000Z

    EDDY HEAT FLUKES AT DRAKE PASSAGE DUE TO MESOSCALE MOTIONS A Thesis by RICARDO LUIS ROJAS RECABAL Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE May... 1982 Major Subject: Oceanography EDDY HEAT FLUXES AT DRAKE PASSAGE DUE TO MESOSCALE NOTIONS A Thesis by RICARDO LUIS ROJAS RECABAL Approved as to style and content by: was )W-~ Member em er May 1982 ABSTRACT Eddy Heat Fluxes at Drake Passage...

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

    SciTech Connect (OSTI)

    Li, Dongsheng

    2014-05-01T23:59:59.000Z

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

  8. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Calibrated Probabilistic Mesoscale Weather Field Forecasting: The Geostatist...

    E-Print Network [OSTI]

    Raftery, Adrian

    permission. Calibrated Probabilistic Mesoscale Weather Field Forecasting: The Geostatist... Yulia Gel; Adrian

  9. The nonlinear coupling between gyroradius scale turbulence and mesoscale magnetic islands in fusion plasmas

    SciTech Connect (OSTI)

    Hornsby, W. A.; Peeters, A. G.; Snodin, A. P.; Casson, F. J.; Camenen, Y.; Szepesi, G. [Department of Physics, Centre for Fusion, Space, and Astrophysics, University of Warwick, Coventry (United Kingdom); Siccinio, M.; Poli, E. [Max-Planck-Institut fuer Plasmaphysik, Boltzmannstrasse 2, D-85748 Garching bei Muenchen (Germany)

    2010-09-15T23:59:59.000Z

    The interaction between small scale turbulence (of the order of the ion Larmor radius) and mesoscale magnetic islands is investigated within the gyrokinetic framework. Turbulence, driven by background temperature and density gradients, over nonlinear mode coupling, pumps energy into long wavelength modes, and can result in an electrostatic vortex mode that coincides with the magnetic island. The strength of the vortex is strongly enhanced by the modified plasma flow response connected with the change in topology, and the transport it generates can compete with the parallel motion along the perturbed magnetic field. Despite the stabilizing effect of sheared plasma flows in and around the island, the net effect of the island is a degradation of the confinement. When density and temperature gradients inside the island are below the threshold for turbulence generation, turbulent fluctuations still persist through turbulence convection and spreading. The latter mechanisms then generate a finite transport flux and, consequently, a finite pressure gradient in the island. A finite radial temperature gradient inside the island is also shown to persist due to the trapped particles, which do not move along the field around the island. In the low collisionality regime, the finite gradient in the trapped population leads to the generation of a bootstrap current, which reduces the neoclassical drive.

  10. Mesoscale predictability of an extreme warm-season precipitation event

    E-Print Network [OSTI]

    Odins, Andrew Michael

    2005-02-17T23:59:59.000Z

    . The Penn State University/NCAR Mesoscale Model version 5 (MM5) was used to conduct predictability experiments, which follow closely to the research conducted by Zhang et al. A control simulation initialized at 00Z 1 July is established over a 30-km grid...

  11. MESOSCALE MODELLING OF WIND ENERGY OVER NON-HOMOGENEOUS TERRAIN

    E-Print Network [OSTI]

    Pielke, Roger A.

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

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

    E-Print Network [OSTI]

    Boyer, Edmond

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

  13. Characterization of Caribbean Meso-Scale Eddies Jose M. Lopez

    E-Print Network [OSTI]

    Gilbes, Fernando

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

  14. Mesoscale simulations of surfactant dissolution and mesophase formation

    E-Print Network [OSTI]

    P. Prinsen; P. B. Warren; M. A. J. Michels

    2002-04-22T23:59:59.000Z

    The evolution of the contact zone between pure surfactant and solvent has been studied by mesoscale simulation. It is found that mesophase formation becomes diffusion controlled and follows the equilibrium phase diagram adiabatically almost as soon as individual mesophases can be identified, corresponding to times in real systems of order 10 microseconds.

  15. LANSCE School on Neutron Scattering: Materials at the Mesoscale

    E-Print Network [OSTI]

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

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

    E-Print Network [OSTI]

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

  17. School of Meteorology Comprehensive Exam Policy Below is the Comprehensive Exam Policy as approved by the School of Meteorology Faculty at the

    E-Print Network [OSTI]

    Oklahoma, University of

    , tropical meteorology, mesoscale meteorology, turbulence and computational fluid dynamics. Normally

  18. Sensitivity of Tropical Cyclone Intensity to Ventilation in an Axisymmetric Model National Center for Atmospheric Research,* Boulder, Colorado

    E-Print Network [OSTI]

    Tang, Brian

    into the boundary layer. The sensitivity of tropical cyclone intensity to ventilation can be viewed in the context mixing above the boundary layer. In the latter, ventilation weakens the eyewall entropy front, resulting, an oscillatory intensity regime materializes and is tied to transient convective bursts and strong downdrafts

  19. Respective roles of shallow convection and stratiform rainfall on the simulation of Madden-Julian Oscillation.

    SciTech Connect (OSTI)

    Fu, Joshua Xiouhua [IPRC/SOEST/UH; Wang, Bin [IPRC& DM/SOEST/UH; Yeh, Hsi-Chyi

    2010-03-15T23:59:59.000Z

    Respective Roles of Shallow Convection and Stratiform Rainfall on the Simulation of Madden Julian Oscillation Joshua Xiouhua Fu IPRC, SOEST, University of Hawaii The IPRC/UH Hybrid-coupled GCM (HcGCM), which combined ECHAM-4 AGCM with UH intermediate ocean model, produces robust Tropical Intra-Seasonal Oscillations including the boreal-winter MJO and boreal-summer Monsoon Intra-Seasonal Oscillation. In this study, two sets of sensitivity experiments (i.e., short-term retrospective forecast of one MJO event observed during TOGA COARE and long-term free integrations) have been carried out to understand the respective roles of shallow-convection and stratiform rainfall on the simulations and predictions of the MJO. Major findings are summarized as following: Shallow-convection ahead of MJO deep convection moistens the lower-troposphere and preconditions the movement of the MJO. Present study shows that this process is very important to the eastward propagating speed of the MJO. A significant fraction of stratiform rainfall (~30%; stratiform part vs. total rainfall) is needed for ECHAM-4 to have a robust MJO. The above findings suggest that in addition to deep convection, shallow convection and stratiform rainfall needs to be well represented in conventional GCMs to ensure a robust model MJO.

  20. Heat distribution by natural convection

    SciTech Connect (OSTI)

    Balcomb, J.D.; Yamaguchi, K.

    1983-01-01T23:59:59.000Z

    Natural convection between spaces in a building can play a major role in energy transfer. Two situations are investigated: convection through a single doorway into a remote room, and a convective loop in a two-story house with a south sunspace where a north stairway serves as the return path. A doorway-sizing equation is given for the single-door case. Detailed data are given from the monitoring of airflow in one two-story house and summary data are given for five others. Observations on the nature of the airflow and design guidelines are presented.

  1. Heat distribution by natural convection

    SciTech Connect (OSTI)

    Balcomb, J.D.

    1985-01-01T23:59:59.000Z

    Natural convection can provide adequate heat distribution in many situtations that arise in buildings. This is appropriate, for example, in passive solar buildings where some rooms tend to be more strongly solar heated than others or to reduce the number of heating units required in a building. Natural airflow and heat transport through doorways and other internal building apertures is predictable and can be accounted for in the design. The nature of natural convection is described, and a design chart is presented appropriate to a simple, single-doorway situation. Natural convective loops that can occur in buildings are described and a few design guidelines are presented.

  2. Cirrus cloud-temperature interactions over a tropical station, Gadanki from lidar and satellite observations

    SciTech Connect (OSTI)

    S, Motty G, E-mail: mottygs@gmail.com; Satyanarayana, M., E-mail: mottygs@gmail.com; Krishnakumar, V., E-mail: mottygs@gmail.com; Dhaman, Reji k., E-mail: mottygs@gmail.com [Department of Optoelectronics, University of Kerala, Kariavattom, Trivandrum-695 581, Kerala (India)

    2014-10-15T23:59:59.000Z

    The cirrus clouds play an important role in the radiation budget of the earth's atmospheric system and are important to characterize their vertical structure and optical properties. LIDAR measurements are obtained from the tropical station Gadanki (13.5{sup 0} N, 79.2{sup 0} E), India, and meteorological indicators derived from Radiosonde data. Most of the cirrus clouds are observed near to the tropopause, which substantiates the strength of the tropical convective processes. The height and temperature dependencies of cloud height, optical depth, and depolarization ratio were investigated. Cirrus observations made using CALIPSO satellite are compared with lidar data for systematic statistical study of cirrus climatology.

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

    E-Print Network [OSTI]

    Schlegel, Nicole-Jeanne

    2011-01-01T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

    PT May; C Jakob; JH Mather

    2004-05-30T23:59:59.000Z

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

  5. Development and evaluation of a convection scheme for use in climate models

    SciTech Connect (OSTI)

    Emanuel, K.A. [Massachusetts Inst. of Tech., Cambridge, MA (United States). Program for Atmospheres, Oceans, and Climate] [Massachusetts Inst. of Tech., Cambridge, MA (United States). Program for Atmospheres, Oceans, and Climate; Zivkovic-Rothman, M. [Atmospheric and Environmental Research, Inc., Cambridge, MA (United States)] [Atmospheric and Environmental Research, Inc., Cambridge, MA (United States)

    1999-06-01T23:59:59.000Z

    Cumulus convection is a key process in controlling the water vapor content of the atmosphere, which is in turn the largest feedback mechanism for climate change in global climate models. Yet scant attention has been paid to designing convective representations that attempt to handle water vapor with fidelity, and even less to evaluating their performance. Here the authors attempt to address this deficiency by designing a representation of cumulus convection with close attention paid to convective water fluxes and by subjecting the scheme to rigorous tests using sounding array data. The authors maintain that such tests, in which a single-column model is forced by large-scale processes measured by or inferred from the sounding data, must be carried out over a period at least as long as the radiative-subsidence timescale--about 30 days--governing the water vapor adjustment time. The authors also argue that the observed forcing must be preconditioned to guarantee integral enthalpy conservation, else errors in the single-column prediction may be falsely attributed to convective schemes. Optimization of the new scheme`s parameters is performed using one month of data from the intensive flux array operating during the Tropical Ocean Global Atmosphere Coupled Ocean-Atmosphere Response Experiment, with the aid of the adjoint of the linear tangent of the single-column model. Residual root-mean-square errors, after optimization, are about 15% in relative humidity and .8 K in temperature. It is difficult to reject the hypothesis that the residual errors are due to noise in the forcing. Evaluation of the convective scheme is performed using Global Atmospheric Research Program Atlantic Tropical Experiment data. The performance of the scheme is compared to that of a few other schemes used in current climate models. It is also shown that a vertical resolution better than 50 mb in pressure is necessary for accurate prediction of atmospheric water vapor.

  6. Heat distribution by natural convection

    SciTech Connect (OSTI)

    Balcomb, J.D.

    1985-01-01T23:59:59.000Z

    Natural convection can provide adequate heat distribution in many situations that arise in buildings. This is appropriate, for example, in passive solar buildings where some rooms tend to be more strongly solar heated than others. Natural convection can also be used to reduce the number of auxiliary heating units required in a building. Natural airflow and heat transport through doorways and other internal building apertures are predictable and can be accounted for in the design. The nature of natural convection is described, and a design chart is presented appropriate to a simple, single-doorway situation. Experimental results are summarized based on the monitoring of 15 passive solar buildings which employ a wide variety of geometrical configurations including natural convective loops.

  7. Penetrative turbulence associated with mesoscale surface heat flux variations

    E-Print Network [OSTI]

    Alam, Jahrul M

    2015-01-01T23:59:59.000Z

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

  8. Quantum fluctuations and saturable absorption in mesoscale lasers

    SciTech Connect (OSTI)

    Roy-Choudhury, Kaushik [Department of Physics and Astronomy, University of Southern California, Los Angeles, California 90089-0484 (United States); Levi, A. F. J. [Department of Physics and Astronomy, University of Southern California, Los Angeles, California 90089-0484 (United States); Department of Electrical Engineering, University of Southern California, Los Angeles, California 90089-2533 (United States)

    2011-04-15T23:59:59.000Z

    We present a quantum-mechanical treatment of fluctuations and saturable absorption in mesoscale lasers. The time evolution of the density matrix is obtained from numerical integration and field-field and intensity-intensity correlations are calculated to obtain steady-state linewidth and photon statistics. Inclusion of a saturable absorber in the otherwise homogeneous medium is shown to suppress lasing, increase fluctuations, and enhance spontaneous emission near threshold.

  9. Mesoscale modeling of metal-loaded high explosives

    SciTech Connect (OSTI)

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

    2010-01-01T23:59:59.000Z

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

  10. Mesoscale Modeling of LX-17 Under Isentropic Compression

    SciTech Connect (OSTI)

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

    2010-03-06T23:59:59.000Z

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

  11. Interval eigenproblem in tropical and fuzzy algebra Tolerance eigenproblem in tropical algebra

    E-Print Network [OSTI]

    Mitchener, Paul

    Interval eigenproblem in tropical and fuzzy algebra Tolerance eigenproblem in tropical algebra Tolerance eigenproblem in fuzzy algebra Tolerance interval eigenvectors in tropical and fuzzy algebra Martin Workshop Birmingham, May 16, 2013 #12;Interval eigenproblem in tropical and fuzzy algebra Tolerance

  12. Convective heat flow probe

    DOE Patents [OSTI]

    Dunn, J.C.; Hardee, H.C.; Striker, R.P.

    1984-01-09T23:59:59.000Z

    A convective heat flow probe device is provided which measures heat flow and fluid flow magnitude in the formation surrounding a borehole. The probe comprises an elongate housing adapted to be lowered down into the borehole; a plurality of heaters extending along the probe for heating the formation surrounding the borehole; a plurality of temperature sensors arranged around the periphery of the probe for measuring the temperature of the surrounding formation after heating thereof by the heater elements. The temperature sensors and heater elements are mounted in a plurality of separate heater pads which are supported by the housing and which are adapted to be radially expanded into firm engagement with the walls of the borehole. The heat supplied by the heater elements and the temperatures measured by the temperature sensors are monitored and used in providing the desired measurements. The outer peripheral surfaces of the heater pads are configured as segments of a cylinder and form a full cylinder when taken together. A plurality of temperature sensors are located on each pad so as to extend along the length and across the width thereof, with a heating element being located in each pad beneath the temperature sensors. An expansion mechanism driven by a clamping motor provides expansion and retraction of the heater pads and expandable packet-type seals are provided along the probe above and below the heater pads.

  13. Feedbacks in a simple prognostic tropical climate model

    SciTech Connect (OSTI)

    Sherwood, S.C. (Scripps Institution of Oceanography, La Jolla, CA (United States))

    1999-07-01T23:59:59.000Z

    A simple four-cell model of the tropical atmosphere in equilibrium with its boundaries is introduced, which can support a variable diabatic circulation and prognostic temperature and humidity profiles. The model is used to predict atmospheric perturbations away from the observed base state. Prognostic variables include radiation, surface fluxes, and dynamic transports, with temperature and water vapor levels determined by conservation constraints. The model includes a specially developed water vapor scheme that performs favorably compared with observations. The model is used to simulate the local and nonlocal sensitivity of the tropical maritime atmosphere to changes in surface temperature and other boundary conditions at very large horizontal scales. The main findings are as follows: (i) The sensitivity of boundary layer convergence to sea surface temperature (SST) variations depends on the behavior of convective heating over cooler regions and may be overestimated by heuristic models that ignore or oversimplify thermodynamic and radiative constraints; (ii) The maintenance of humidity equilibrium over weakly convective areas is modulated by local radiative feedback; (iii) Evaporation feedbacks on SST may be overestimated by heuristic arguments that do not carefully treat atmospheric water transport. An explanation for the constant-relative humidity behavior of general circulation models under climate changes is also offered based on the results.

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

    E-Print Network [OSTI]

    Hogan, Robin

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

  15. FeCycle: Attempting an iron biogeochemical budget from a mesoscale SF6 tracer experiment in unperturbed low iron waters

    E-Print Network [OSTI]

    Wilhelm, Steven W.

    FeCycle: Attempting an iron biogeochemical budget from a mesoscale SF6 tracer experiment to ocean physics. In summer 2003 we conducted FeCycle, a 10-day mesoscale tracer release in HNLC waters SE biogeochemical budget from a mesoscale SF6 tracer experiment in unperturbed low iron waters, Global Biogeochem

  16. Proceedings in Applied Mathematics and Mechanics, 31 October 2007 Parametrization for Mesoscale Ocean Transport through Random Flow

    E-Print Network [OSTI]

    Kramer, Peter

    Proceedings in Applied Mathematics and Mechanics, 31 October 2007 Parametrization for Mesoscale a mathematical approach based on homogenization theory toward representing the effects of mesoscale coherent in parameterizing the transport effects of sub-grid scale flow structures appearing in mesoscale oceanic turbulence

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

    E-Print Network [OSTI]

    Politècnica de Catalunya, Universitat

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

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

    E-Print Network [OSTI]

    Boyer, Edmond

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

  19. THE USE OF SPATIAL CONSTRAINTS IN THE DERIVATION OF MESOSCALE SEA SURFACE CURRENT FIELDS FROM MULTI-SENSOR SATELLITE DATA

    E-Print Network [OSTI]

    Hamburg,.Universität

    THE USE OF SPATIAL CONSTRAINTS IN THE DERIVATION OF MESOSCALE SEA SURFACE CURRENT FIELDS FROM MULTI images are used for the computation of mesoscale surface currents in the Northern and Southern Baltic for the derivation of mesoscale sea surface currents using multi-sensor / multi-channel satellite images by means

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

    E-Print Network [OSTI]

    Niyogi, Dev

    (GEM) for Mesoscale Weather Forecasting Applications DEV NIYOGI Department of Agronomy, and Department form 13 May 2008) ABSTRACT Current land surface schemes used for mesoscale weather forecast models use model (GEM) as a land surface scheme for mesoscale weather forecasting model applications. The GEM

  1. THE PRECIPITATION REGIME OF DRONNING MAUD LAND, ANTARCTICA, DERIVED FROM AMPS (ANTARCTIC MESOSCALE PREDICTION SYSTEM) ARCHIVE DATA

    E-Print Network [OSTI]

    Schlosser, Elisabeth

    THE PRECIPITATION REGIME OF DRONNING MAUD LAND, ANTARCTICA, DERIVED FROM AMPS (ANTARCTIC MESOSCALE. Manning2) 1) Institute of Meteorology and Geophysics, University of Innsbruck, Austria 2) Mesoscale the temporal and spatial distribution of precipitation in DML using AMPS (Antarctic Mesoscale Prediction System

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

    E-Print Network [OSTI]

    Wang, Yuqing

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

  3. IEEE TRANSACTIONS ON ROBOTICS, VOL. 25, NO. 5, OCTOBER 2009 1047 A New Mechanism for Mesoscale Legged

    E-Print Network [OSTI]

    Webster III, Robert James

    IEEE TRANSACTIONS ON ROBOTICS, VOL. 25, NO. 5, OCTOBER 2009 1047 A New Mechanism for Mesoscale for a novel mechanism for robotic legged locomotion at the mesoscale (from hundreds of microns to tens mesoscale locomotion tasks, in- cluding endoscopic capsule robot locomotion in the gastrointestinal tract

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

    E-Print Network [OSTI]

    Smith, K. Shafer

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

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

    E-Print Network [OSTI]

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

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

    E-Print Network [OSTI]

    Raman, Sethu

    Mesoscale Atmospheric Dispersion, 2001, Ed. Z. Boybeyi, WIT Publications, Southampton, UK, Advances surface­atmosphere exchanges in mesoscale air pollution systems Devdutta S. Niyogi & Sethu Raman North-physiological leaf scaling approach. Finally, of particular relevance to mesoscale applications is the area averaging

  7. Characterization of Mesoscale Coiled-Coil Peptide-Porphyrin Brian J. Pepe-Mooney, Bashkim Kokona, and Robert Fairman*

    E-Print Network [OSTI]

    Fairman, Robert

    Characterization of Mesoscale Coiled-Coil Peptide-Porphyrin Complexes Brian J. Pepe-Mooney, Bashkim-assemble to form mesoscale filaments and serve as a scaffold for porphyrin interaction. In our earlier work mesoscale fibrils were formed, taking advantage of the types of porphyrin interactions that are present

  8. The Surface Expression of Semidiurnal Internal Tides near a Strong Source at Hawaii. Part II: Interactions with Mesoscale Currents*

    E-Print Network [OSTI]

    : Interactions with Mesoscale Currents* C. CHAVANNE, P. FLAMENT, AND D. LUTHER School of Ocean and Earth Science in the light of the interaction of internal tides with energetic surface-intensified mesoscale currents locations at critical topographic slopes through idealized mesoscale currents approximating the observed

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

    E-Print Network [OSTI]

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

  10. Nature of the Mesoscale Boundary Layer Height and Water Vapor Variability Observed 14 June 2002 during the IHOP_2002 Campaign

    E-Print Network [OSTI]

    Guichard, Francoise

    Nature of the Mesoscale Boundary Layer Height and Water Vapor Variability Observed 14 June 2002, Boulder, Colorado (Manuscript received 4 September 2007, in final form 23 June 2008) ABSTRACT Mesoscale at the mesoscale, with the spatial pattern and the magnitude of the variability changing from day to day. On 14

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

    E-Print Network [OSTI]

    Miami, University of

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

  12. Copyright (to be inserted by the publisher ) Mesoscale Simulation of the Evolution of the Grain Boundary Character

    E-Print Network [OSTI]

    Rohrer, Gregory S.

    Citation & Copyright (to be inserted by the publisher ) Mesoscale Simulation of the Evolution; Simulation; Grain boundary energy; Mullins Equation Abstract. A mesoscale, variational simulation of grain to the mesoscale simulation of grain growth in large two dimensional systems to study the evolution of the grain

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

    E-Print Network [OSTI]

    Yang, Vigor

    1 Combustion in Meso-scale Vortex Chambers Ming-hsun Wu* , Yanxing Wang, Vigor Yang and Richard A) #12;2 COMBUSTION IN MESO-SCALE VORTEX CHAMBERS Ming-hsun Wu, Yanxing Wang, Vigor Yang and Richard A with the chemical energy varying from 25 to 174W. For the largest combustion volume, hydrogen and hydrocarbons

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

    E-Print Network [OSTI]

    Wang, Shuguang

    2006-04-12T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Wang, Shuguang

    2006-04-12T23:59:59.000Z

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

  16. ARM - Midlatitude Continental Convective Clouds

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Jensen, Mike; Bartholomew, Mary Jane; Genio, Anthony Del; Giangrande, Scott; Kollias, Pavlos

    Convective processes play a critical role in the Earth's energy balance through the redistribution of heat and moisture in the atmosphere and their link to the hydrological cycle. Accurate representation of convective processes in numerical models is vital towards improving current and future simulations of Earths climate system. Despite improvements in computing power, current operational weather and global climate models are unable to resolve the natural temporal and spatial scales important to convective processes and therefore must turn to parameterization schemes to represent these processes. In turn, parameterization schemes in cloud-resolving models need to be evaluated for their generality and application to a variety of atmospheric conditions. Data from field campaigns with appropriate forcing descriptors have been traditionally used by modelers for evaluating and improving parameterization schemes.

  17. Tropical Warm Pool International Cloud Experiment TWP-ICE Cloud and rain characteristics in the Australian Monsoon

    SciTech Connect (OSTI)

    May, P.T., Jakob, C., and Mather, J.H.

    2004-05-31T23:59:59.000Z

    The impact of oceanic convection on its environment and the relationship between the characteristics of the convection and the resulting cirrus characteristics is still not understood. An intense airborne measurement campaign combined with an extensive network of ground-based observations is being planned for the region near Darwin, Northern Australia, during January-February, 2006, to address these questions. The Tropical Warm Pool International Cloud Experiment (TWP-ICE) will be the first field program in the tropics that attempts to describe the evolution of tropical convection, including the large scale heat, moisture, and momentum budgets, while at the same time obtaining detailed observations of cloud properties and the impact of the clouds on the environment. The emphasis will be on cirrus for the cloud properties component of the experiment. Cirrus clouds are ubiquitous in the tropics and have a large impact on their environment but the properties of these clouds are poorly understood. A crucial product from this experiment will be a dataset suitable to provide the forcing and testing required by cloud-resolving models and parameterizations in global climate models. This dataset will provide the necessary link between cloud properties and the models that are attempting to simulate them.

  18. Phase behavior and mesoscale solubilization in aqueous solutions of hydrotropes

    E-Print Network [OSTI]

    Deepa Subramanian; Mikhail A. Anisimov

    2013-09-27T23:59:59.000Z

    Hydrotropes are amphiphilic molecules that are too small to spontaneously form equilibrium structures in aqueous solutions, but form dynamic, noncovalent assemblies, referred to as clusters. In the presence of a hydrophobic compound, these clusters seem to get stabilized leading to the formation of long-lived, highly stable mesoscopic droplets, a phenomenon that we call mesoscale solubilization. In this work, we focus on the unusual mesoscopic properties of aqueous solutions of a nonionic hydrotrope, namely tertiary butyl alcohol (TBA), on addition of various hydrophobic compounds. Aqueous TBA solutions, in about 3 to 8 mol percent TBA concentration range and about 0 to 25 deg. C temperature range, show the presence of short-ranged (0.5 nm), short-lived (tens of picoseconds) molecular clusters which result in anomalies of the thermodynamic properties. These clusters are transient but do not relax by diffusion, thus distinctly different from conventional concentration fluctuations. In this concentration and temperature range, upon the addition of a third (more hydrophobic) component to TBA-water solutions, long-lived mesoscopic droplets of about 100 nm size are observed. In this work, we clarify the ambiguity behind the definition of solubility and elucidate the phenomenon of mesoscale solubilization. A systematic study of the macro and meso phase behavior of three ternary systems TBA-water-propylene oxide, TBA-water-isobutyl alcohol, and TBA-water-cyclohexane has been carried out. We differentiate between molecular solubility, mesoscale solubilization, and macroscopic phase separation. We have confirmed that practically stable aqueous colloids can be created from small molecules, without addition of surfactants or polymers. Such kind of novel materials may find applications in the design of various processes and products, ranging from pharmaceuticals to cosmetics and agrochemicals.

  19. Customizing mesoscale self-assembly with 3D printing

    E-Print Network [OSTI]

    M. Poty; G. Lumay; N. Vandewalle

    2013-10-17T23:59:59.000Z

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

  20. Analytical Rescaling of Polymer Dynamics from Mesoscale Simulations

    E-Print Network [OSTI]

    I. Y. Lyubimov; J. McCarty; A. Clark; M. G. Guenza

    2011-03-10T23:59:59.000Z

    We present a theoretical approach to scale the artificially fast dynamics of simulated coarse-grained polymer liquids down to its realistic value. As coarse-graining affects entropy and dissipation, two factors enter the rescaling: inclusion of intramolecular vibrational degrees of freedom, and rescaling of the friction coefficient. Because our approach is analytical, it is general and transferable. Translational and rotational diffusion of unentangled and entangled polyethylene melts, predicted from mesoscale simulations of coarse-grained polymer melts using our rescaling procedure, are in quantitative agreement with united atom simulations and with experiments.

  1. Mesoscale simulations of polymer dynamics in microchannel flows

    E-Print Network [OSTI]

    L. Cannavacciuolo; R. G. Winkler; G. Gompper

    2007-09-24T23:59:59.000Z

    The non-equilibrium structural and dynamical properties of flexible polymers confined in a square microchannel and exposed to a Poiseuille flow are investigated by mesoscale simulations. The chain length and the flow strength are systematically varied. Two transport regimes are identified, corresponding to weak and strong confinement. For strong confinement, the transport properties are independent of polymer length. The analysis of the long-time tumbling dynamics of short polymers yields non-periodic motion with a sublinear dependence on the flow strength. We find distinct differences for conformational as well as dynamical properties from results obtained for simple shear flow.

  2. Combating tropical deforestation in Haiti

    SciTech Connect (OSTI)

    Pellek, R.

    1990-09-01T23:59:59.000Z

    This article outlines the findings of Tropical Forestry Action Plan (TFAP), which was part of an international initiative on tropical deforestation. Ten specific recommendations are addressed. Haiti has lost more than 97% of its forestland, so emphasis should be placed on replenishing the forest cover.

  3. NATURAL CONVECTION IN ROOM GEOMETRIES

    SciTech Connect (OSTI)

    Gadgil, A.; Bauman, Fred; Kammerud, R.; Ruberg, K.

    1980-06-01T23:59:59.000Z

    Computer programs have been developed to numerically simulate natural convection in room geometries in two and three dimensions. The programs have been validated using published data from the literature, results from a full-scale experiment performed at Massachusetts Institute of Technology, and results from a small-scale experiment reported here. One of the computer programs has been used to study the influence of natural convection on the thermal performance of a single thermal zone in a direct-gain passive solar building. The results indicate that the building heating loads calculated by standard building energy analysis methods may be in error by as much as 50% as a result of their use of common assumptions regarding the convection processes which occur in an enclosure. It is also found that the convective heat transfer coefficients between the air and the enclosure surfaces can be substantially different from the values assumed in the standard building energy analysis methods, and can exhibit significant variations across a given surface.

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

    SciTech Connect (OSTI)

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

    2010-11-01T23:59:59.000Z

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

  5. Generated using version 3.0 of the official AMS LATEX template Predictability and genesis of Hurricane Karl (2010) examined

    E-Print Network [OSTI]

    2010-01-01T23:59:59.000Z

    and column moisture are allowed to build up in this region35 until the eventual formation of a tropical by the development of a synoptic-20 scale disturbance; e.g., a low-pressure system along a tropical wave, a monsoon associated with mesoscale convective systems within the synoptic-25 scale disturbance acts to moisten

  6. Seismic Constraints on Interior Solar Convection

    E-Print Network [OSTI]

    Hanasoge, S M; DeRosa, M L

    2010-01-01T23:59:59.000Z

    We constrain the velocity spectral distribution of global-scale solar convective cells at depth using techniques of local helioseismology. We calibrate the sensitivity of helioseismic waves to large-scale convective cells in the interior by analyzing simulations of waves propagating through a velocity snapshot of global solar convection via methods of time-distance helioseismology. Applying identical analysis techniques to observations of the Sun, we are able to bound from above the magnitudes of solar convective cells as a function of spatial convective scale. We find that convection at a depth of $r/R_\\odot = 0.95$ with spatial extent $\\ell <20$, where $\\ell$ is the spherical harmonic degree, comprise weak flow systems, on the order of 15 m/s or less. Convective features deeper than $r/R_\\odot = 0.95$ are more difficult to image due to the rapidly decreasing sensitivity of helioseismic waves.

  7. Copyrighted Material What Is Tropical Ecology?

    E-Print Network [OSTI]

    Landweber, Laura

    Copyrighted Material What Is Tropical Ecology? Asking the question, What is tropical ecology? may seem akin to asking questions such as, Who is buried in Grant's tomb? Tropical ecology is the study of the ecology of tropical regions. But so what? Consider these questions: First, what is ecology? What are its

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

    SciTech Connect (OSTI)

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

    2012-04-11T23:59:59.000Z

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

  9. Heat transfers in a double-skin roof ventilated by natural convection in summer time

    E-Print Network [OSTI]

    Biwole, Pascal; Pompeo, C

    2013-01-01T23:59:59.000Z

    The double-skin roofs investigated in this paper are formed by adding a metallic screen on an existing sheet metal roof. The system enhances passive cooling of dwellings and can help diminishing power costs for air conditioning in summer or in tropical and arid countries. In this work, radiation, convection and conduction heat transfers are investigated. Depending on its surface properties, the screen reflects a large amount of oncoming solar radiation. Natural convection in the channel underneath drives off the residual heat. The bi-dimensional numerical simulation of the heat transfers through the double skin reveals the most important parameters for the system's efficiency. They are, by order of importance, the sheet metal surface emissivity, the screen internal and external surface emissivity, the insulation thickness and the inclination angle for a channel width over 6 cm. The influence of those parameters on Rayleigh and Nusselt numbers is also investigated. Temperature and air velocity profiles on seve...

  10. Tropical Cyclones and Climate Change

    E-Print Network [OSTI]

    Knutson, Thomas R.

    Whether the characteristics of tropical cyclones have changed or will change in a warming climate — and if so, how — has been the subject of considerable investigation, often with conflicting results. Large amplitude ...

  11. Tropical bases by regular projections

    E-Print Network [OSTI]

    Hept, Kerstin

    2007-01-01T23:59:59.000Z

    We consider the tropical variety $\\mathcal{T}(I)$ of a prime ideal $I$ generated by the polynomials $f_1, ..., f_r$ and revisit the regular projection technique introduced by Bieri and Groves from a computational point of view. In particular, we show that $I$ has a short tropical basis of cardinality at most $r + \\codim I + 1$ at the price of increased degrees, and we provide a computational description of these bases.

  12. Comparison of Simulated and Observed Continental Tropical Anvil Clouds and Their Radiative Heating Profiles

    SciTech Connect (OSTI)

    Powell, Scott W.; Houze, R.; Kumar, Anil; McFarlane, Sally A.

    2012-09-06T23:59:59.000Z

    Vertically pointing millimeter-wavelength radar observations of anvil clouds extending from mesoscale convective systems (MCSs) that pass over an Atmospheric Radiation Measurement Program (ARM) field site in Niamey, Niger, are compared to anvil structures generated by the Weather Research and Forecasting (WRF) mesoscale model using six different microphysical schemes. The radar data provide the statistical distribution of the radar reflectivity values as a function of height and anvil thickness. These statistics are compared to the statistics of the modeled anvil cloud reflectivity at all altitudes. Requiring the model to be statistically accurate at all altitudes is a stringent test of the model performance. The typical vertical profile of radiative heating in the anvil clouds is computed from the radar observations. Variability of anvil structures from the different microphysical schemes provides an estimate of the inherent uncertainty in anvil radiative heating profiles. All schemes underestimate the optical thickness of thin anvils and cirrus, resulting in a bias of excessive net anvil heating in all of the simulations.

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

    E-Print Network [OSTI]

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

    2014-01-01T23:59:59.000Z

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

  14. Dynamics of Mesoscale Magnetic Field in Diffusive Shock Acceleration

    E-Print Network [OSTI]

    P. H. Diamond; M. A. Malkov

    2006-05-15T23:59:59.000Z

    We present a theory for the generation of mesoscale ($kr_{g}\\ll 1$, where $r_{g}$ is the cosmic ray gyroradius) magnetic fields during diffusive shock acceleration. The decay or modulational instability of resonantly excited Alfven waves scattering off ambient density perturbations in the shock environment naturally generates larger scale fields. For a broad spectrum of perturbations, the physical mechanism of energy transfer is random refraction, represented by diffusion of Alfven wave packet in $k-$space. The scattering field can be produced directly by the decay instability or by the Drury instability, a hydrodynamic instability driven by the cosmic ray pressure gradient. This process is of interest to acceleration since it generates waves of longer wavelength, and so enables the confinement and acceleration of higher energy particles. This process also limits the intensity of resonantly generated turbulent magnetic field on $r_{g}$ scales.

  15. Mesoscale modeling of colloidal suspensions with adsorbing solutes

    E-Print Network [OSTI]

    Rei Tatsumi; Osamu Koike; Yukio Yamaguchi

    2015-01-14T23:59:59.000Z

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

  16. Mesoscale polycrystal calculations of damage in spallation in metals

    SciTech Connect (OSTI)

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

    2010-01-01T23:59:59.000Z

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

  17. Coastal Wave Generation and Wave Breaking over Terrain: Two Problems in Mesoscale Wave Dynamics 

    E-Print Network [OSTI]

    Qian, Tingting

    2010-07-14T23:59:59.000Z

    Two problems in mesoscale wave dynamics are addressed: (i) wave-turbulence interaction in a breaking mountain wave and (ii) gravity wave generation associated with coastal heating gradients. The mean and turbulent structures in a breaking mountain...

  18. Mesoscale X-Ray Fluorescence (XRF) Mapping Reveals Growth Processes for Stromatolites from the Nsuze Group 

    E-Print Network [OSTI]

    Quezergue, Kimbra Rose

    2014-12-05T23:59:59.000Z

    Stromatolites are formed by physical, biological, and chemical processes, and combinations of specific processes produced the great variety of textures and morphologies in the geologic record. I here introduce a new technique for mesoscale chemical...

  19. Rationalizing the Spatial Distribution of Mesoscale Eddy Diffusivity in Terms of Mixing Length Theory

    E-Print Network [OSTI]

    Bates, Michael

    Observations and theory suggest that lateral mixing by mesoscale ocean eddies only reaches its maximum potential at steering levels, surfaces at which the propagation speed of eddies approaches that of the mean flow. Away ...

  20. Mesoscale X-Ray Fluorescence (XRF) Mapping Reveals Growth Processes for Stromatolites from the Nsuze Group

    E-Print Network [OSTI]

    Quezergue, Kimbra Rose

    2014-12-05T23:59:59.000Z

    Stromatolites are formed by physical, biological, and chemical processes, and combinations of specific processes produced the great variety of textures and morphologies in the geologic record. I here introduce a new technique for mesoscale chemical...

  1. Coastal Wave Generation and Wave Breaking over Terrain: Two Problems in Mesoscale Wave Dynamics

    E-Print Network [OSTI]

    Qian, Tingting

    2010-07-14T23:59:59.000Z

    Two problems in mesoscale wave dynamics are addressed: (i) wave-turbulence interaction in a breaking mountain wave and (ii) gravity wave generation associated with coastal heating gradients. The mean and turbulent structures in a breaking mountain...

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

    E-Print Network [OSTI]

    Almeida, Rafael Vladimir

    2009-05-15T23:59:59.000Z

    Spot cores from Phase 1 drilling of the main borehole at the San Andreas Fault Observatory at Depth (SAFOD) were mapped to characterize the mesoscale structure and infer paleostress at depth. Cores were oriented by comparing mapped structures...

  3. Enhancement of Mesoscale Eddy Stirring at Steering Levels in the Southern Ocean

    E-Print Network [OSTI]

    Marshall, John C.

    Meridional cross sections of effective diffusivity in the Southern Ocean are presented and discussed. The effective diffusivity, K[subscript eff], characterizes the rate at which mesoscale eddies stir properties on interior ...

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

    E-Print Network [OSTI]

    Golda, Dariusz, 1979-

    2008-01-01T23:59:59.000Z

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

  5. Energy transport using natural convection boundary layers

    SciTech Connect (OSTI)

    Anderson, R.

    1986-04-01T23:59:59.000Z

    Natural convection is one of the major modes of energy transport in passive solar buildings. There are two primary mechanisms for natural convection heat transport through an aperture between building zones: (1) bulk density differences created by temperature differences between zones; and (2) thermosyphon pumping created by natural convection boundary layers. The primary objective of the present study is to compare the characteristics of bulk density driven and boundary layer driven flow, and discuss some of the advantages associated with the use of natural convection boundary layers to transport energy in solar building applications.

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

    SciTech Connect (OSTI)

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

    2003-11-01T23:59:59.000Z

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

  7. Utilizing CLASIC observations and multiscale models to study the impact of improved Land surface representation on modeling cloud- convection

    SciTech Connect (OSTI)

    Niyogi, Devdutta S. [Purdue

    2013-06-07T23:59:59.000Z

    The CLASIC experiment was conducted over the US southern great plains (SGP) in June 2007 with an objective to lead an enhanced understanding of the cumulus convection particularly as it relates to land surface conditions. This project was design to help assist with understanding the overall improvement of land atmosphere convection initiation representation of which is important for global and regional models. The study helped address one of the critical documented deficiency in the models central to the ARM objectives for cumulus convection initiation and particularly under summer time conditions. This project was guided by the scientific question building on the CLASIC theme questions: What is the effect of improved land surface representation on the ability of coupled models to simulate cumulus and convection initiation? The focus was on the US Southern Great Plains region. Since the CLASIC period was anomalously wet the strategy has been to use other periods and domains to develop the comparative assessment for the CLASIC data period, and to understand the mechanisms of the anomalous wet conditions on the tropical systems and convection over land. The data periods include the IHOP 2002 field experiment that was over roughly same domain as the CLASIC in the SGP, and some of the DOE funded Ameriflux datasets.

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

    E-Print Network [OSTI]

    Guglielmi, Y.

    2008-01-01T23:59:59.000Z

    of these effects in fractured reservoirs, at an intermediateinteractions in a fractured carbonate reservoir inferredis a mesoscale fractured carbonate reservoir (30 m × 30 m ×

  9. Midlevel Ventilation's Constraint on Tropical Cyclone Intensity

    E-Print Network [OSTI]

    Tang, Brian Hong-An

    Midlevel ventilation, or the flux of low-entropy air into the inner core of a tropical cyclone (TC), is a hypothesized mechanism by which environmental vertical wind shear can constrain a tropical cyclone’s intensity. An ...

  10. A Ventilation Index for Tropical Cyclones

    E-Print Network [OSTI]

    Tang, Brian

    An important environmental control of both tropical cyclone intensity and genesis is vertical wind shear. One hypothesized pathway by which vertical shear affects tropical cyclones is midlevel ventilation—or the flux of ...

  11. Estimating tropical cyclone precipitation risk in Texas

    E-Print Network [OSTI]

    Zhu, Laiyin

    This paper uses a new rainfall algorithm to simulate the long-term tropical cyclone precipitation (TCP) climatology in Texas based on synthetic tropical cyclones generated from National Center for Atmospheric Research/National ...

  12. NISTIR 6095 Horizontal Convective Condensation of

    E-Print Network [OSTI]

    Oak Ridge National Laboratory

    NISTIR 6095 Horizontal Convective Condensation of Alternative Refrigerants within a Micro-Fin Tube Horizontal Convective Condensation of Alternative Refrigerants Within a Micro-Fin Tube Mark A. Kedzierski J for flow boiling pressure drop in a smooth tube. Correlation of the pressure drop measurements suggested

  13. Collective phase description of oscillatory convection

    SciTech Connect (OSTI)

    Kawamura, Yoji, E-mail: ykawamura@jamstec.go.jp [Institute for Research on Earth Evolution, Japan Agency for Marine-Earth Science and Technology, Yokohama 236-0001 (Japan)] [Institute for Research on Earth Evolution, Japan Agency for Marine-Earth Science and Technology, Yokohama 236-0001 (Japan); Nakao, Hiroya [Department of Mechanical and Environmental Informatics, Tokyo Institute of Technology, Tokyo 152-8552 (Japan)] [Department of Mechanical and Environmental Informatics, Tokyo Institute of Technology, Tokyo 152-8552 (Japan)

    2013-12-15T23:59:59.000Z

    We formulate a theory for the collective phase description of oscillatory convection in Hele-Shaw cells. It enables us to describe the dynamics of the oscillatory convection by a single degree of freedom which we call the collective phase. The theory can be considered as a phase reduction method for limit-cycle solutions in infinite-dimensional dynamical systems, namely, stable time-periodic solutions to partial differential equations, representing the oscillatory convection. We derive the phase sensitivity function, which quantifies the phase response of the oscillatory convection to weak perturbations applied at each spatial point, and analyze the phase synchronization between two weakly coupled Hele-Shaw cells exhibiting oscillatory convection on the basis of the derived phase equations.

  14. Asian Clinical Tropical Medicine Bangkok, Thailand

    E-Print Network [OSTI]

    Minnesota, University of

    Asian Clinical Tropical Medicine Bangkok, Thailand July 21 ­ August 3, 2012 Join the Faculty, and the University of Minnesota as they co-host the fourth Asian Clinical Tropical Medical Course in beautiful Bangkok, Thailand. Healthcare providers with experience and/or a special interest in clinical tropical

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

    E-Print Network [OSTI]

    Niyogi, Dev

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

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

    E-Print Network [OSTI]

    Takada, Shoji

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

  17. Journal of the Mechanics and Physics of Solids 56 (2008) 14501459 Shocks and slip systems: Predictions from a mesoscale theory of

    E-Print Network [OSTI]

    Sethna, James P.

    2008-01-01T23:59:59.000Z

    : Predictions from a mesoscale theory of continuum dislocation dynamics S. Limkumnerda,Ã, J.P. Sethnab a Zernike developed mesoscale continuum theory of dislocation dynamics, we derive three predictions about plasticity

  18. MICRO-SEISMOMETERS VIA ADVANCED MESO-SCALE FABRICATION

    SciTech Connect (OSTI)

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

    2014-11-07T23:59:59.000Z

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

  19. Manufacturing Ultra-Precision Meso-scale Products by Coining

    SciTech Connect (OSTI)

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

    2010-02-18T23:59:59.000Z

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

  20. Interpreting Temperature Strain Data from Meso-Scale Clathrate Experiments

    SciTech Connect (OSTI)

    Leeman, John R [ORNL; Rawn, Claudia J [ORNL; Ulrich, Shannon M [ORNL; Elwood Madden, Megan [University of Oklahoma, Norman; Phelps, Tommy Joe [ORNL

    2012-01-01T23:59:59.000Z

    Gas hydrates are important in global climate change, carbon sequestra- tion, and seafloor stability. Currently, formation and dissociation pathways are poorly defined. We present a new approach for processing large amounts of data from meso-scale experiments, such as the LUNA distributed sensing system (DSS) in the seafloor process simulator (SPS) at Oak Ridge National Laboratory. The DSS provides a proxy for temperature measurement with a high spatial resolution allowing the heat of reaction during gas hydrate formation/dissociation to aid in locating clathrates in the vessel. The DSS fibers are placed in the sediment following an Archimedean spiral design and then the position of each sensor is solved by iterating over the arc length formula with Newtons method. The data is then gridded with 1 a natural neighbor interpolation algorithm to allow contouring of the data. The solution of the sensor locations is verified with hot and cold stimulus in known locations. An experiment was preformed with a vertically split column of sand and silt. The DSS system clearly showed hydrate forming in the sand first, then slowly creeping into the silt. Similar systems and data processing techniques could be used for monitoring of hydrates in natural environments or in any situation where a hybrid temperature/strain index is useful. Further ad- vances in fiber technology allow the fiber to be applied in any configuration and the position of each sensor to be precisely determined making practical applications easier.

  1. Mesoscale and Large-Eddy Simulations for Wind Energy

    SciTech Connect (OSTI)

    Marjanovic, N

    2011-02-22T23:59:59.000Z

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

  2. Emergent Mesoscale Phenomena in Magnetized Accretion Disc Turbulence

    E-Print Network [OSTI]

    Simon, Jacob B; Armitage, Philip J

    2012-01-01T23:59:59.000Z

    We study how the structure and variability of magnetohydrodynamic (MHD) turbulence in accretion discs converge with domain size. Our results are based on a series of vertically stratified local simulations, computed using the Athena code, that have fixed spatial resolution, but varying radial and azimuthal extent (from \\Delta R = 0.5H to 16H, where H is the vertical scale height). We show that elementary local diagnostics of the turbulence, including the Shakura-Sunyaev {\\alpha} parameter, the ratio of Maxwell stress to magnetic energy, and the ratio of magnetic to fluid stresses, converge to within the precision of our measurements for spatial domains of radial size Lx \\geq 2H. We obtain {\\alpha} = 0.02-0.03, consistent with recent results. Very small domains (Lx = 0.5H) return anomalous results, independent of spatial resolution. The convergence with domain size is only valid for a limited set of diagnostics: larger spatial domains admit the emergence of dynamically important mesoscale structures. In our la...

  3. Microphysical Effects Determine Macrophysical Response for Aerosol Impacts on Deep Convective Clouds

    SciTech Connect (OSTI)

    Fan, Jiwen; Leung, Lai-Yung R.; Rosenfeld, Daniel; Chen, Qian; Li, Zhanqing; Zhang, Jinqiang; Yan, Hongru

    2013-11-26T23:59:59.000Z

    Deep convective clouds (DCCs) play a crucial role in the general circulation and energy and hydrological cycle of our climate system. Anthropogenic and natural aerosol particles can influence DCCs through changes in cloud properties, precipitation regimes, and radiation balance. Modeling studies have reported both invigoration and suppression of DCCs by aerosols, but none has fully quantified aerosol impacts on convection life cycle and radiative forcing. By conducting multiple month-long cloud-resolving simulations with spectral-bin cloud microphysics that capture the observed macro- and micro-physical properties of summer convective clouds in the tropics and mid-latitudes, this study provides the first comprehensive look at how aerosols affect cloud cover, cloud top height (CTH), and radiative forcing. Observations validate these simulation results. We find that microphysical aerosol effects contribute predominantly to increased cloud cover and CTH by inducing larger amount of smaller but longer lasting ice particles in the stratiform/anvils of DCCs with dynamical aerosol effects contributing at most ~ 1/4 of the total increase of cloud cover. The overall effect is a radiative warming in the atmosphere (3 to 5 W m-2) with strong surface cooling (-5 to -8 W m-2). Herein we clearly identified mechanisms more important than and additional to the invigoration effects hypothesized previously that explain the consistent signatures of increased cloud tops area and height by aerosols in DCCs revealed by observations.

  4. Interannual variability of summer biochemical enhancement in relation to mesoscale eddies at the shelf break in the vicinity of the Pribilof Islands,

    E-Print Network [OSTI]

    Interannual variability of summer biochemical enhancement in relation to mesoscale eddies the 1300-km-long eastern shelf break accompanied by a mesoscale eddy field (Okkonen, 2001a). Eddies occur., 2002). Mesoscale eddies, which penetrate to depths of at least 1000 m (Roden, 1995; Mizobata et al

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

    E-Print Network [OSTI]

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

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

    E-Print Network [OSTI]

    Harting, Jens

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

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

    E-Print Network [OSTI]

    Madeleine, Jean-Baptiste

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

  8. arXiv:1205.6074v1[physics.bio-ph]28May2012 Mesoscale symmetries explain dynamical equivalence of food webs

    E-Print Network [OSTI]

    arXiv:1205.6074v1[physics.bio-ph]28May2012 Mesoscale symmetries explain dynamical equivalence is to identify mesoscale structures that have distinct dynamical implications. In this paper we present show that this equivalence is rooted in mesoscale symmetries that exist in these webs. Certain

  9. Analyses of the role of grain boundaries in mesoscale dynamic fracture resistance of SiCSi3N4 intergranular nanocomposites

    E-Print Network [OSTI]

    Tomar, Vikas

    Analyses of the role of grain boundaries in mesoscale dynamic fracture resistance of SiC­Si3N4 with SiC dispersions as well as Si3N4 matrix of mesoscale dimensions ($1 lm) are considered to have, cohesive finite element method (CFEM) based mesoscale dynamic fracture anal- yses of SiC­Si3N4

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

    E-Print Network [OSTI]

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

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

    E-Print Network [OSTI]

    Chaboureau, Jean-Pierre

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

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

    E-Print Network [OSTI]

    Hartley, Roger

    ARCHITECTURE OF THE MERCURY MESOSCALE METEOROLOGICAL DATA FUSION C. Fields, C. Cavendish, M. Coombs mesoscale meteorological data fusion system is being developed as an intelligent interface between the U.S. Army's Integrated Meteorological System IM[ETS) mesoscale database and tactical decision aids (TDAs

  13. REVIEWS OF GEOPHYSICS: U.S. NATIONAL REPORT TO INTERNATIONAL UNION OF GEODESY AND GEOPHYSICS COOL SEASON CYCLOGENESIS AND ASSOCIATED MESOSCALE WEATHER

    E-Print Network [OSTI]

    Businger, Steven

    -1994 COOL SEASON CYCLOGENESIS AND ASSOCIATED MESOSCALE WEATHER Steven Businger Department of Meteorology (NWS) and a profusion of recent field experiments1 are bringing an explosion of mesoscale2 observations to probe the mesoscale structure and evolution of winter cyclones in recent years. Many recent advances

  14. Mesoscale Patterns Formed by Evaporation of a Polymer Solution in the Proximity of a Sphere on a Smooth Substrate: Molecular Weight

    E-Print Network [OSTI]

    Lin, Zhiqun

    Mesoscale Patterns Formed by Evaporation of a Polymer Solution in the Proximity of a Sphere evaporation as a simple, lithography- and external-field- free route to well-ordered mesoscale structures weight (MW) effect on the mesoscale polymer patterns formed by drying a drop of polymer solution

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

    E-Print Network [OSTI]

    Takada, Shoji

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

  16. Tests of an Ensemble Kalman Filter for Mesoscale and Regional-Scale Data Assimilation. Part I: Perfect Model Experiments

    E-Print Network [OSTI]

    Meng, Zhiyong

    Tests of an Ensemble Kalman Filter for Mesoscale and Regional-Scale Data Assimilation. Part I the potential of using the ensemble Kalman filter (EnKF) for mesoscale and regional-scale data assimilation are assimilated. 1. Introduction The ensemble-based data assimilation method [en- semble Kalman filter (En

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

    E-Print Network [OSTI]

    Meng, Zhiyong

    Tests of an Ensemble Kalman Filter for Mesoscale and Regional-Scale Data Assimilation. Part II In Part I of this two-part work, the feasibility of using an ensemble Kalman filter (EnKF) for mesoscale that using an ensemble Kalman filter (EnKF) in the context of a perfect model (i.e., both the truth

  18. arXiv:1207.3736v1[math.DS]16Jul2012 Meso-scale obstructions to

    E-Print Network [OSTI]

    arXiv:1207.3736v1[math.DS]16Jul2012 Meso-scale obstructions to stability of 1D center manifolds, the impact of meso-scale structural properties on the dynamics of complex networks. As a motivational exam

  19. Convective Cooling and Passive Stack Improvements in Motors (Presentation)

    SciTech Connect (OSTI)

    Bennion, K.

    2014-06-01T23:59:59.000Z

    This presentation discusses current research at NREL in convective cooling and passive stack improvements in motors.

  20. Convective heat transfer inside passive solar buildings

    SciTech Connect (OSTI)

    Jones, R.W.; Balcomb, J.D.; Yamaguchi, K.

    1983-01-01T23:59:59.000Z

    Natural convection between spaces in a building can play a major role in energy transfer. Two situations are investigated: convection through a single doorway into a remote room, and a convective loop in a two-story house with a south sunspace where a north stairway serves as the return path. A doorway-sizing equation is given for the single-door case. Detailed data are given from the monitoring of airflow in one two-story house and summary data are given for five others. Observations on the nature of the airflow and design guidelines are presented.

  1. Convective heat transfer inside passive solar buildings

    SciTech Connect (OSTI)

    Jones, R.W.; Balcomb, J.D.; Yamaguchi, K.

    1983-11-01T23:59:59.000Z

    Natural convection between spaces in a building which play a major role in energy transfer are discussed. Two situations are investigated: Convection through a single doorway into a remote room, and a convective loop in a two story house with a south sunspace where a north stairway serves as the return path. A doorway sizing equation is given for the single door case. Data from airflow monitoring in one two-story house and summary data for five others are presented. The nature of the airflow and design guidelines are presented.

  2. Mesoscale Modeling During Mixed-Phase Arctic Cloud Experiment

    SciTech Connect (OSTI)

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

    2005-03-18T23:59:59.000Z

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

  3. Multiscale dynamics of atmospheric and oceanic variability in the climate system

    E-Print Network [OSTI]

    Subramanian, Aneesh C.

    2012-01-01T23:59:59.000Z

    applied to the Oceanic Mesoscale in the South Eastassimilation at the oceanic mesoscale: A review. JOURNAL-scale circulations and mesoscale convective activity in

  4. Immersed Boundary Methods for High-Resolution Simulation of Atmospheric Boundary-Layer Flow Over Complex Terrain

    E-Print Network [OSTI]

    Lundquist, Katherine Ann

    2010-01-01T23:59:59.000Z

    large-eddy simulations within mesoscale simulations for windEddy Simulation of a Mesoscale Convective Internal Boundary185, 1957. Pielke, R. , Mesoscale Meteorological Modeling,

  5. Circulation and convection in the Irminger Sea

    E-Print Network [OSTI]

    Våge, Kjetil

    2010-01-01T23:59:59.000Z

    Aspects of the circulation and convection in the Irminger Sea are investigated using a variety of in-situ, satellite, and atmospheric reanalysis products. Westerly Greenland tip jet events are intense, small-scale wind ...

  6. Modeling convection in the Greenland Sea

    E-Print Network [OSTI]

    Bhushan, Vikas

    1998-01-01T23:59:59.000Z

    A detailed examination of the development of a deep convection event observed in the Greenland Sea in 1988-89 is carried out through a combination of modeling, scale estimates, and data analysis. We develop a prognostic ...

  7. Marangoni convection in droplets on superhydrophobic surfaces

    E-Print Network [OSTI]

    Tam, Daniel

    We consider a small droplet of water sitting on top of a heated superhydrophobic surface. A toroidal convection pattern develops in which fluid is observed to rise along the surface of the spherical droplet and to accelerate ...

  8. An investigation of rainfall distribution within a mesoscale network in the middle Brazos River area

    E-Print Network [OSTI]

    Bell, Carroll Wilson

    1966-01-01T23:59:59.000Z

    AN INVESTIGATION OF RAINFALL DISTRIBUTION WITHIN A MESOSCALE NETWORK IN THE MIDDLE BRAZOS RIVER AREA A Thesis By CARROLL W. BELL Submitted to the Graduate College of the Texas A&M University in partial fulfillment of the requirements... for the degree of MASTER OF SCIENCE May 1966 Ma]or Subject: METEOROLOGY AN INVESTIGATION OF RAINFALL DISTRIBUTION WITHIN A MESOSCALE NETWORK IN THE MIDDLE BRAZOS RIVER AREA A Thesis By CARROLL W. BELL Approved as to style and content by: C airman o...

  9. Evaluation of tropical cloud and precipitation statistics of CAM3 using CloudSat and CALIPSO data

    SciTech Connect (OSTI)

    Zhang, Y; Klein, S; Boyle, J; Mace, G G

    2008-11-20T23:59:59.000Z

    The combined CloudSat and CALIPSO satellite observations provide the first simultaneous measurements of cloud and precipitation vertical structure, and are used to examine the representation of tropical clouds and precipitation in the Community Atmosphere Model Version 3 (CAM3). A simulator package utilizing a model-to-satellite approach facilitates comparison of model simulations to observations, and a revised clustering method is used to sort the subgrid-scale patterns of clouds and precipitation into principal cloud regimes. Results from weather forecasts performed with CAM3 suggest that the model underestimates the horizontal extent of low and mid-level clouds in subsidence regions, but overestimates that of high clouds in ascending regions. CAM3 strongly overestimates the frequency of occurrence of the deep convection with heavy precipitation regime, but underestimates the horizontal extent of clouds and precipitation at low and middle levels when this regime occurs. This suggests that the model overestimates convective precipitation and underestimates stratiform precipitation consistent with a previous study that used only precipitation observations. Tropical cloud regimes are also evaluated in a different version of the model, CAM3.5, which uses a highly entraining plume in the parameterization of deep convection. While the frequency of occurrence of the deep convection with heavy precipitation regime from CAM3.5 forecasts decreases, the incidence of the low clouds with precipitation and congestus regimes increases. As a result, the parameterization change does not reduce the frequency of precipitating convection that is far too high relative to observations. For both versions of CAM, clouds and precipitation are overly reflective at the frequency of the CloudSat radar and thin clouds that could be detected by the lidar only are underestimated.

  10. Origins of convective activity over Panama

    E-Print Network [OSTI]

    Strager, Christopher Stephen

    1989-01-01T23:59:59.000Z

    ORIGINS OF CONVECTIVE ACTIVITY OVER PANAMA A Thesis by CHRISTOPHER STEPHEN STRAGER Submitted to the Office of Graduate Studies of Texas ARM University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE August 1989... Major Subject: Meteorology ORIGINS OF CONVECTIVE ACTIVITY OVER PANAMA A Thesis by CHRISTOPHER STEPHEN STRAGER Approved as to style and content by: Steven W. ons (Chair of Committee) Kenneth C. Brundidge (Member) Rud lf J. Freund ( ember...

  11. Convective cores in galactic cooling flows

    E-Print Network [OSTI]

    A. Kritsuk; T. Plewa; E. Mueller

    2001-05-02T23:59:59.000Z

    We use hydrodynamic simulations with adaptive grid refinement to study the dependence of hot gas flows in X-ray luminous giant elliptical galaxies on the efficiency of heat supply to the gas. We consider a number of potential heating mechanisms including Type Ia supernovae and sporadic nuclear activity of a central supermassive black hole. As a starting point for this research we use an equilibrium hydrostatic recycling model (Kritsuk 1996). We show that a compact cooling inflow develops, if the heating is slightly insufficient to counterbalance radiative cooling of the hot gas in the central few kiloparsecs. An excessive heating in the centre, instead, drives a convectively unstable outflow. We model the onset of the instability and a quasi-steady convective regime in the core of the galaxy in two-dimensions assuming axial symmetry. Provided the power of net energy supply in the core is not too high, the convection remains subsonic. The convective pattern is dominated by buoyancy driven large-scale mushroom-like structures. Unlike in the case of a cooling inflow, the X-ray surface brightness of an (on average) isentropic convective core does not display a sharp maximum at the centre. A hybrid model, which combines a subsonic peripheral cooling inflow with an inner convective core, appears to be stable. We also discuss observational implications of these results.

  12. Seismic Sounding of Convection in the Sun

    E-Print Network [OSTI]

    Hanasoge, Shravan; Sreenivasan, Katepalli R

    2015-01-01T23:59:59.000Z

    Our Sun, primarily composed of ionized hydrogen and helium, has a surface temperature of 5777~K and a radius $R_\\odot \\approx 696,000$ km. In the outer $R_\\odot/3$, energy transport is accomplished primarily by convection. Using typical convective velocities $u\\sim100\\,\\rm{m\\,s^{-1}}$ and kinematic viscosities of order $10^{-4}$ m$^{2}$s$^{-1}$, we obtain a Reynolds number $Re \\sim 10^{14}$. Convection is thus turbulent, causing a vast range of scales to be excited. The Prandtl number, $Pr$, of the convecting fluid is very low, of order $10^{-7}$\\,--\\,$10^{-4}$, so that the Rayleigh number ($\\sim Re^2 Pr$) is on the order of $10^{21}\\,-\\,10^{24}$. Solar convection thus lies in extraordinary regime of dynamical parameters, highly untypical of fluid flows on Earth. Convective processes in the Sun drive global fluid circulations and magnetic fields, which in turn affect its visible outer layers ("solar activity") and, more broadly, the heliosphere ("space weather"). The precise determination of the depth of sola...

  13. The tropical double description method

    E-Print Network [OSTI]

    Allamigeon, Xavier; Goubault, Eric

    2010-01-01T23:59:59.000Z

    We develop a tropical analogue of the classical double description method allowing one to compute an internal representation (in terms of vertices) of a polyhedron defined externally (by inequalities). The heart of the tropical algorithm is a characterization of the extreme points of a polyhedron in terms of a system of constraints which define it. We show that checking the extremality of a point reduces to checking whether there is only one minimal strongly connected component in an hypergraph. The latter problem can be solved in almost linear time, which allows us to eliminate quickly redundant generators. We report extensive tests (including benchmarks from an application to static analysis) showing that the method outperforms experimentally the previous ones by orders of magnitude. The present tools also lead to worst case bounds which improve the ones provided by previous methods.

  14. A Satellite Study of Tropical Moist Convection and Environmental Variability: A Moisture and Thermal Budget Analysis

    E-Print Network [OSTI]

    Masunaga, Hirohiko

    radiometer and scatterometer aboard different platforms. Satellite measurements of atmospheric parameters of moisture and dry static energy and their vertical flux at cloud base from satellite observations alone convergence for highly organized systems; 2) FT diabatic heating is largely offset on an instantaneous basis

  15. A Simple Multicloud Parameterization for Convectively Coupled Tropical Waves. Part II: Nonlinear Simulations

    E-Print Network [OSTI]

    Majda, Andrew J.

    , British Columbia, Canada ANDREW J. MAJDA Department of Mathematics, and Center for Atmosphere Ocean clouds, and deep penetrative cumulus clouds (Lin and Johnson 1996; Johnson et al. 1999). Furthermore

  16. Intersecting Cold Pools: Convective Cloud Organization by Cold Pools over Tropical Ocean

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn OtherEnergy International Fuel7Radiative Transfer

  17. Influence of Tropical Tropopause Layer Cooling on Atlantic Hurricane Activity

    E-Print Network [OSTI]

    Solomon, Susan

    Virtually all metrics of Atlantic tropical cyclone activity show substantial increases over the past two decades. It is argued here that cooling near the tropical tropopause and the associated decrease in tropical cyclone ...

  18. The Role of the Tropics in Abrupt Climate Changes

    SciTech Connect (OSTI)

    Fedorov, Alexey [Yale University] [Yale University

    2013-12-07T23:59:59.000Z

    Topics addressed include: abrupt climate changes and ocean circulation in the tropics; what controls the ocean thermal structure in the tropics; a permanent El Niño in paleoclimates; the energetics of the tropical ocean.

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

    E-Print Network [OSTI]

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

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

    E-Print Network [OSTI]

    Jochum, Markus

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

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

    E-Print Network [OSTI]

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

    2012-02-02T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

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

    2010-10-01T23:59:59.000Z

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

  3. Convection automated logic oven control

    SciTech Connect (OSTI)

    Boyer, M.A.; Eke, K.I. [Apollo U.S.A. Inc., Orlando, FL (United States)] [Apollo U.S.A. Inc., Orlando, FL (United States)

    1998-03-01T23:59:59.000Z

    For the past few years, there has been a greater push to bring more automation to the cooling process. There have been attempts at automated cooking using a wide range of sensors and procedures, but with limited success. The authors have the answer to the automated cooking process; this patented technology is called Convection AutoLogic (CAL). The beauty of the technology is that it requires no extra hardware for the existing oven system. They use the existing temperature probe, whether it is an RTD, thermocouple, or thermistor. This means that the manufacturer does not have to be burdened with extra costs associated with automated cooking in comparison to standard ovens. The only change to the oven is the program in the central processing unit (CPU) on the board. As for its operation, when the user places the food into the oven, he or she is required to select a category (e.g., beef, poultry, or casseroles) and then simply press the start button. The CAL program then begins its cooking program. It first looks at the ambient oven temperature to see if it is a cold, warm, or hot start. CAL stores this data and then begins to look at the food`s thermal footprint. After CAL has properly detected this thermal footprint, it can calculate the time and temperature at which the food needs to be cooked. CAL then sets up these factors for the cooking stage of the program and, when the food has finished cooking, the oven is turned off automatically. The total time for this entire process is the same as the standard cooking time the user would normally set. The CAL program can also compensate for varying line voltages and detect when the oven door is opened. With all of these varying factors being monitored, CAL can produce a perfectly cooked item with minimal user input.

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

    SciTech Connect (OSTI)

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

    2014-06-01T23:59:59.000Z

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

  5. Asteroseismic Diagnostics of Stellar Convective Cores

    E-Print Network [OSTI]

    Anwesh Mazumdar; Sarbani Basu; Braxton L. Collier; Pierre Demarque

    2006-08-16T23:59:59.000Z

    We present a detailed study of the small frequency separations as diagnostics of the mass of the convective core and evolutionary stage of solar-type stars. We demonstrate how the small separations can be combined to provide sensitive tests for the presence of convective overshoot at the edge of the core. These studies are focused on low degree oscillation modes, the only modes expected to be detected in distant stars. Using simulated data with realistic errors, we find that the mass of the convective core can be estimated to within 5% if the total stellar mass is known. Systematic errors arising due to uncertainty in the mass could be up to 20%. The evolutionary stage of the star, determined in terms of the central hydrogen abundance using our proposed technique, however, is much less sensitive to the mass estimate.

  6. ORIGINAL ARTICLE Mitigation needs adaptation: Tropical forestry

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    ORIGINAL ARTICLE Mitigation needs adaptation: Tropical forestry and climate change Manuel R adapt to this change. This paper discusses how tropical forestry practices can contribute to maintaining Forestry Research, P.O. Box 6596 JKPWB, Jakarta 10065, Indonesia e-mail: m.guariguata@cgiar.org J. P

  7. Tropical Western Pacific CART Site

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron Spin Transition in2,EHSS A-Z SiteManhattan ProjectMayARM-00-005Tropical

  8. A CONVECTIVE HEAT TRANSFER MODEL FOR SIMULATION OF ROOMS WITH

    E-Print Network [OSTI]

    A CONVECTIVE HEAT TRANSFER MODEL FOR SIMULATION OF ROOMS WITH ATTACHED WALL JETS By WEIXIU KONGQuest Information and Learning Company. #12;II A CONVECTIVE HEAT TRANSFER MODEL FOR SIMULATION OF ROOMS

  9. LARGE EDDY SIMULATION OF NATURAL AND MIXED CONVECTION AIRFLOW INDOORS

    E-Print Network [OSTI]

    Chen, Qingyan "Yan"

    coordinate Greek symbols : Thermal expansion coefficient t : Time step : Filter size : Kinematic viscocity convection, such as winter heating by a baseboard heater; forced convection, such as free cooling in shoulder

  10. Fluidized bed boiler convective zone tube replacement

    SciTech Connect (OSTI)

    Not Available

    1991-03-21T23:59:59.000Z

    A major problem with the Georgetown University Atomspheric-Pressure, Fluidized-Bed Combustor-Boiler (GU AFBC) experienced during the first six years of operation was tube erosion. Previous corrective measures for in-bed tube erosion appeared to be effective, but excessive wear of the convective zone tubes was still occurring, and the entire heat transfer tube bundle in the boiler required replacement. In the planned project,the eroded tubes would be replaced, and the convective zone modified to eliminate the problem. Progress is discussed.

  11. Convection and dynamo action in B stars

    E-Print Network [OSTI]

    Augustson, Kyle C; Toomre, Juri

    2010-01-01T23:59:59.000Z

    Main-sequence massive stars possess convective cores that likely harbor strong dynamo action. To assess the role of core convection in building magnetic fields within these stars, we employ the 3-D anelastic spherical harmonic (ASH) code to model turbulent dynamics within a 10 solar mass main-sequence (MS) B-type star rotating at 4 times the solar rate. We find that strong (900 kG) magnetic fields arise within the turbulence of the core and penetrate into the stably stratified radiative zone. These fields exhibit complex, time-dependent behavior including reversals in magnetic polarity and shifts between which hemisphere dominates the total magnetic energy.

  12. Urban morphological analysis for mesoscale meteorological and dispersion modeling applications : current issues

    SciTech Connect (OSTI)

    Burian, S. J. (Steven J.); Brown, M. J. (Michael J.); Ching, J. (Jason); Cheuk, M. L. (Mang Lung); Yuan, M. (May); McKinnon, A. T. (Andrew T.); Han, W. S. (Woo Suk)

    2004-01-01T23:59:59.000Z

    Accurate predictions of air quality and atmospheric dispersion at high spatial resolution rely on high fidelity predictions of mesoscale meteorological fields that govern transport and turbulence in urban areas. However, mesoscale meteorological models do not have the spatial resolution to directly simulate the fluid dynamics and thermodynamics in and around buildings and other urban structures that have been shown to modify micro- and mesoscale flow fields (e.g., see review by Bornstein 1987). Mesoscale models therefore have been adapted using numerous approaches to incorporate urban effects into the simulations (e.g., see reviews by Brown 2000 and Bornstein and Craig 2002). One approach is to introduce urban canopy parameterizations to approximate the drag, turbulence production, heating, and radiation attenuation induced by sub-grid scale buildings and urban surface covers (Brown 2000). Preliminary results of mesoscale meteorological and air quality simulations for Houston (Dupont et al. 2004) demonstrated the importance of introducing urban canopy parameterizations to produce results with high spatial resolution that accentuates variability, highlights important differences, and identifies critical areas. Although urban canopy parameterizations may not be applicable to all meteorological and dispersion models, they have been successfully introduced and demonstrated in many of the current operational and research mode mesoscale models, e.g., COAMPS (Holt et al. 2002), HOTMAC (Brown and Williams 1998), MM5 (e.g., Otte and Lacser 2001; Lacser and Otte 2002; Dupont et al. 2004), and RAMS (Rozoff et al. 2003). The primary consequence of implementing an urban parameterization in a mesoscale meteorological model is the need to characterize the urban terrain in greater detail. In general, urban terrain characterization for mesoscale modeling may be described as the process of collecting datasets of urban surface cover physical properties (e.g., albedo, emissivity) and morphology (i.e., ground elevation, building and tree height and geometry characteristics) and then processing the data to compute physical cover and morphological parameters. Many of the surface cover and morphological parameters required for mesoscale meteorological models are also needed by atmospheric dispersion models. Thus, most of the discussion below is relevant to both types of modeling. In this paper, the term urban morphological analysis will be used to define the component of urban terrain characterization concerned with the morphological parameters. Furthermore, the focus will be building morphological parameters; therefore, the term urban morphological analysis will refer exclusively to the task of inventorying, computing or estimating building morphological parameters. Several approaches to perform urban morphological analysis exist; however, all have in common three types of practice issues related to the uncertainty of (1) data, (2) parameter definitions and calculation methods, and (3) extrapolation techniques. The objective of this paper is to describe the state-of-the-practice of urban morphological analysis by reviewing the primary approaches presented in the literature and outlining and commenting on key aspects of the three types of practice issues listed above.

  13. Convection and convective overshooting in stars more massive than 10 $M_\\odot$

    E-Print Network [OSTI]

    Jie, Jin; Lv, Guoliang

    2015-01-01T23:59:59.000Z

    In this paper, four sets of evolutionary models are computed with different values of the mixing length parameter $\\alpha_{\\rm p}$ and the overshooting parameter $\\delta_{\\rm ov}$. The properties of the convective cores and the convective envelopes are studied in the massive stars. We get three conclusions: First, the larger $\\alpha_{\\rm p}$ leads to enhancing the convective mixing, removing the chemical gradient, and increasing the convective heat transfer efficiency. Second, core potential $\\phi_{\\rm c} = M_{\\rm c} / R_{\\rm c}$ describes sufficiently the evolution of a star, whether it is a red or blue supergiant at central helium ignition. Third, the discontinuity of hydrogen profile above the hydrogen burning shell seriously affect the occurrence of blue loops in the Hertzsprung--Russell diagram.

  14. Solar Dynamics, Rotation, Convection and Overshoot

    E-Print Network [OSTI]

    Hanasoge, S; Roth, M; Schou, J; Schuessler, M; Thompson, M J

    2015-01-01T23:59:59.000Z

    We discuss recent observational, theoretical and modeling progress made in understanding the Sun's internal dynamics, including its rotation, meridional flow, convection and overshoot. Over the past few decades, substantial theoretical and observational effort has gone into appreciating these aspects of solar dynamics. A review of these observations, related helioseismic methodology and inference and computational results in relation to these problems is undertaken here.

  15. The effect of convection on pulsational stability

    E-Print Network [OSTI]

    G. Houdek

    2008-10-29T23:59:59.000Z

    A review on the current state of mode physics in classical pulsators is presented. Two, currently in use, time-dependent convection models are compared and their applications on mode stability are discussed with particular emphasis on the location of the Delta Scuti instability strip.

  16. Convective Instability of a Boundary Layer with

    E-Print Network [OSTI]

    Conrad, Clint

    proportional to the integral over the depth of the lithosphere of the 19 #12;ratio of thermal buoyancy. Such instabilities are driven by the negative thermal buoyancy of the cold lithosphere and retarded largely for driving convective downwelling. For non-Newtonian viscosity with power law exponent n and temperature

  17. Convective and absolute instabilities in eccentric Taylor

    E-Print Network [OSTI]

    Shyamasundar, R.K.

    Convective and absolute instabilities in eccentric Taylor Laboratoire de mécanique des fluides et d and absolute instabilities in Taylor-Couette-Poiseuille flow Benoît PIER Laboratoire de mécanique des fluides flow type often disrupt oil-well drilling By implementing a detailed instability analysis, the dynamics

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

    E-Print Network [OSTI]

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

    2012-01-01T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

    Werth, D.; O'Steen, L.

    2008-02-11T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Anne-Ly Do; Johannes Höfener; Thilo Gross

    2012-07-05T23:59:59.000Z

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

  1. CONVECTION THEORY AND SUB-PHOTOSPHERIC STRATIFICATION

    SciTech Connect (OSTI)

    Arnett, David; Meakin, Casey; Young, Patrick A., E-mail: darnett@as.arizona.ed, E-mail: casey.meakin@gmail.co, E-mail: patrick.young.1@asu.ed [Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States)

    2010-02-20T23:59:59.000Z

    As a preliminary step toward a complete theoretical integration of three-dimensional compressible hydrodynamic simulations into stellar evolution, convection at the surface and sub-surface layers of the Sun is re-examined, from a restricted point of view, in the language of mixing-length theory (MLT). Requiring that MLT use a hydrodynamically realistic dissipation length gives a new constraint on solar models. While the stellar structure which results is similar to that obtained by Yale Rotational Evolution Code (Guenther et al.; Bahcall and Pinsonneault) and Garching models (Schlattl et al.), the theoretical picture differs. A new quantitative connection is made between macro-turbulence, micro-turbulence, and the convective velocity scale at the photosphere, which has finite values. The 'geometric parameter' in MLT is found to correspond more reasonably with the thickness of the superadiabatic region (SAR), as it must for consistency in MLT, and its integrated effect may correspond to that of the strong downward plumes which drive convection (Stein and Nordlund), and thus has a physical interpretation even in MLT. If we crudely require the thickness of the SAR to be consistent with the 'geometric factor' used in MLT, there is no longer a free parameter, at least in principle. Use of three-dimensional simulations of both adiabatic convection and stellar atmospheres will allow the determination of the dissipation length and the geometric parameter (i.e., the entropy jump) more realistically, and with no astronomical calibration. A physically realistic treatment of convection in stellar evolution will require substantial additional modifications beyond MLT, including nonlocal effects of kinetic energy flux, entrainment (the most dramatic difference from MLT found by Meakin and Arnett), rotation, and magnetic fields.

  2. Coastal zone wind energy. Part I. Synoptic and mesoscale controls and distributions of coastal wind energy

    SciTech Connect (OSTI)

    Garstang, M.; Nnaji, S.; Pielke, R.A.; Gusdorf, J.; Lindsey, C.; Snow, J.W.

    1980-03-01T23:59:59.000Z

    This report describes a method of determining coastal wind energy resources. Climatological data and a mesoscale numerical model are used to delineate the available wind energy along the Atlantic and Gulf coasts of the United States. It is found that the spatial distribution of this energy is dependent on the locations of the observing sites in relation to the major synoptic weather features as well as the particular orientation of the coastline with respect to the large-scale wind.

  3. Massively parallel implementation of the Penn State/NCAR Mesoscale Model

    SciTech Connect (OSTI)

    Foster, I.; Michalakes, J.

    1992-12-01T23:59:59.000Z

    Parallel computing promises significant improvements in both the raw speed and cost performance of mesoscale atmospheric models. On distributed-memory massively parallel computers available today, the performance of a mesoscale model will exceed that of conventional supercomputers; on the teraflops machines expected within the next five years, performance will increase by several orders of magnitude. As a result, scientists will be able to consider larger problems, more complex model processes, and finer resolutions. In this paper. we report on a project at Argonne National Laboratory that will allow scientists to take advantage of parallel computing technology. This Massively Parallel Mesoscale Model (MPMM) will be functionally equivalent to the Penn State/NCAR Mesoscale Model (MM). In a prototype study, we produced a parallel version of MM4 using a static (compile-time) coarse-grained ``patch`` decomposition. This code achieves one-third the performance of a one-processor CRAY Y-MP on twelve Intel 1860 microprocessors. The current version of MPMM is based on all MM5 and uses a more fine-grained approach, decomposing the grid as finely as the mesh itself allows so that each horizontal grid cell is a parallel process. This will allow the code to utilize many hundreds of processors. A high-level language for expressing parallel programs is used to implement communication strearns between the processes in a way that permits dynamic remapping to the physical processors of a particular parallel computer. This facilitates load balancing, grid nesting, and coupling with graphical systems and other models.

  4. Massively parallel implementation of the Penn State/NCAR Mesoscale Model

    SciTech Connect (OSTI)

    Foster, I.; Michalakes, J.

    1992-01-01T23:59:59.000Z

    Parallel computing promises significant improvements in both the raw speed and cost performance of mesoscale atmospheric models. On distributed-memory massively parallel computers available today, the performance of a mesoscale model will exceed that of conventional supercomputers; on the teraflops machines expected within the next five years, performance will increase by several orders of magnitude. As a result, scientists will be able to consider larger problems, more complex model processes, and finer resolutions. In this paper. we report on a project at Argonne National Laboratory that will allow scientists to take advantage of parallel computing technology. This Massively Parallel Mesoscale Model (MPMM) will be functionally equivalent to the Penn State/NCAR Mesoscale Model (MM). In a prototype study, we produced a parallel version of MM4 using a static (compile-time) coarse-grained patch'' decomposition. This code achieves one-third the performance of a one-processor CRAY Y-MP on twelve Intel 1860 microprocessors. The current version of MPMM is based on all MM5 and uses a more fine-grained approach, decomposing the grid as finely as the mesh itself allows so that each horizontal grid cell is a parallel process. This will allow the code to utilize many hundreds of processors. A high-level language for expressing parallel programs is used to implement communication strearns between the processes in a way that permits dynamic remapping to the physical processors of a particular parallel computer. This facilitates load balancing, grid nesting, and coupling with graphical systems and other models.

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

    E-Print Network [OSTI]

    Walters, Michael Kent

    1985-01-01T23:59:59.000Z

    values of model variables for static test and kinetic energy calculations . . . . . . . . . 25 2 Results of kinetic energy budget calculations . . 29 ? 1 -5 Surface heating rate (K s x 10 ) . . . . . . . 32 4 Initial values of variables for nonlinear.... These tests provide an important means of debugging the numerical scheme. The validation tests performed on the mesoscale model consisted of a simple static test, calculation of the mass continuity and the kinet. ic energy budget, and performing non...

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

    E-Print Network [OSTI]

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

    2015-01-01T23:59:59.000Z

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

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

    SciTech Connect (OSTI)

    Paul C. Millett; Michael Tonks

    2011-06-01T23:59:59.000Z

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

  8. Scaling of convective velocity in a vertically vibrated granular bed

    E-Print Network [OSTI]

    Tomoya M. Yamada; Hiroaki Katsuragi

    2014-05-30T23:59:59.000Z

    We experimentally study the velocity scaling of granular convection which is a possible mechanism of the regolith migration on the surface of small asteroids. In order to evaluate the contribution of granular convection to the regolith migration, the velocity of granular convection under the microgravity condition has to be revealed. Although it is hard to control the gravitational acceleration in laboratory experiments, scaling relations involving the gravitational effect can be evaluated by systematic experiments. Therefore, we perform such a systematic experiment of the vibration-induced granular convection. From the experimental data, a scaling form for the granular convective velocity is obtained. The obtained scaling form implies that the granular convective velocity can be decomposed into two characteristic velocity components: vibrational and gravitational velocities. In addition, the system size dependence is also scaled. According to the scaling form, the granular convective velocity $v$ depends on the gravitational acceleration $g$ as $v \\propto g^{0.97}$ when the normalized vibrational acceleration is fixed.

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

    E-Print Network [OSTI]

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

    2015-01-01T23:59:59.000Z

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

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

    E-Print Network [OSTI]

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

    2013-08-22T23:59:59.000Z

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

  11. Cloud to ground lightning in tropical cyclone: a study of 34 West Atlantic tropical cyclones from 1986-1996

    E-Print Network [OSTI]

    Coyne, John Michael

    2001-01-01T23:59:59.000Z

    Hurricane Tropical Storm Hurricane Hurricane Andrew Charley Arlene Floyd Alberto Chris Keith Allison Chantal Hugo Jerry Marco Ana Bob Fabian ?8 Andrew Danielle Earl Arlene Emily Alberto Beryl Gordon Allison Dean Erin Jerry Opal... Tropical Storm Hurricane Tropical Storm Hurricane Tropical Storm Hurricane Humcane Tropical Storm Hurricane Andrew Charley Arlene Floyd Alberto Chris Keith Allison Chantal Hugo Jerry Marco Ana Bob Fabian ?8 Andrew Danielle Earl...

  12. Midlevel ventilation's constraint on tropical cyclone intensity

    E-Print Network [OSTI]

    Tang, Brian Hong-An

    2010-01-01T23:59:59.000Z

    Midlevel ventilation, or the flux of low-entropy air into the inner core of a tropical cyclone (TC), is a hypothesized mechanism by which environmental vertical wind shear can constrain a TC's intensity. An idealized ...

  13. Tropical cyclone-ocea~ interactions Isaac Ginis

    E-Print Network [OSTI]

    Rhode Island, University of

    Hurricane Andrew in 1992 exceeded 60 with nearly $30 billion damage. Tropical cyclone modeling efforts over of hurricane track predictions over the last 30 years, in contrast there has been no perceptible improvement

  14. Elements of tropical Pacific decadal variability

    E-Print Network [OSTI]

    Fuckar, Neven-Stjepan

    2003-01-01T23:59:59.000Z

    of the period from 1965 to 1999. Model results show Pacific basin decadal changes, including the prominent 1976-77 climate shift, in agreement with previous research. The reanalysis indicates an evolution intrinsic to the tropical Pacific which propagates...

  15. On the connection between continental-scale land surface processes and the tropical climate in a coupled ocean-atmosphere-land system

    SciTech Connect (OSTI)

    Ma, Hsi-Yen; Mechoso, C. R.; Xue, Yongkang; Xiao, Heng; Neelin, David; Ji, Xuan

    2013-11-15T23:59:59.000Z

    The impact of global tropical climate to perturbations in land surface processes (LSP) are evaluated using perturbations given by different LSP representations of continental-scale in a global climate model that includes atmosphere-ocean interactions. One representation is a simple land scheme, which specifies climatological albedos and soil moisture availability. The other representation is the more comprehensive Simplified Simple Biosphere Model, which allows for interactive soil moisture and vegetation biophysical processes. The results demonstrate that LSP processes such as interactive soil moisture and vegetation biophysical processes have strong impacts on the seasonal mean states and seasonal cycles of global precipitation, clouds, and surface air temperature. The impact is especially significant over the tropical Pacific. To explore the mechanisms for such impact, different LSP representations are confined to selected continental-scale regions where strong interactions of climate-vegetation biophysical processes are present. We find that the largest impact is mainly from LSP perturbations over the tropical African continent. The impact is through anomalous convective heating in tropical Africa due to changes in the surface heat fluxes, which in turn affect basinwide teleconnections in the Pacific through equatorial wave dynamics. The modifications in the equatorial Pacific climate are further enhanced by strong air-sea coupling between surface wind stress and upwelling, as well as effect of ocean memory. Our results further suggest that correct representations of land surface processes, land use change and the associated changes in the deep convection over tropical Africa are crucial to reducing the uncertainty when performing future climate projections under different climate change scenarios.

  16. Laser induced natural convection and thermophoresis

    SciTech Connect (OSTI)

    Wang, C.Y.; Cipolla, J.; Morse, T.F.

    1983-07-01T23:59:59.000Z

    The influence of axial laser volumetric heating and forced convection on the motion of aerosol particles in a vertical tube has been studied. The asymptotic case of constant wall temperature provides simple temperature and velocity profiles that determine the convection and thermophoretic motion of small aerosol particles. For the case in which the flow (in the absence of laser heating) is downward, the laser heating induces upward buoyant motion near the tube center. When the laser heating is taken to be constant (a small absorption limit), a velocity profile may be found that will minimize the distance over which particles are deposited on the wall. Such an observation may have some bearing on the manufacture of preforms from which optical fibers are drawn.

  17. Increase in the Intensity of Postmonsoon Bay of Bengal Tropical Cyclones

    SciTech Connect (OSTI)

    Balaguru, Karthik; Taraphdar, Sourav; Leung, Lai-Yung R.; Foltz, Gregory R.

    2014-05-28T23:59:59.000Z

    The post-monsoon (October-November) tropical cyclone (TC) season in the Bay of Bengal has spawned many of the deadliest storms in recorded history. Here it is shown that the intensity of post-monsoon Bay of Bengal TCs, and the contribution of major TCs to total TC power, increased during 1981-2010. It is found that changes in environmental parameters are responsible for the observed increases in TC intensity. Increases in sea surface temperature and upper ocean heat content made the ocean more conducive to TC development, while enhanced convective instability made the atmosphere more favorable for the growth of TCs. The largest changes in the atmosphere and ocean occurred in the eastern Bay of Bengal, where nearly all major TCs form. These changes are part of positive linear trends, suggesting that the intensity of post-monsoon Bay of Bengal TCs may continue to increase in the future.

  18. Convective Dynamo Simulation with a Grand Minimum

    E-Print Network [OSTI]

    Augustson, Kyle; Miesch, Mark; Toomre, Juri

    2015-01-01T23:59:59.000Z

    The global-scale dynamo action achieved in a simulation of a Sun-like star rotating at thrice the solar rate is assessed. The 3-D MHD Anelastic Spherical Harmonic (ASH) code, augmented with a viscosity minimization scheme, is employed to capture convection and dynamo processes in this G-type star. The simulation is carried out in a spherical shell that encompasses 3.8 density scale heights of the solar convection zone. It is found that dynamo action with a high degree of time variation occurs, with many periodic polarity reversals occurring roughly every 6.2 years. The magnetic energy also rises and falls with a regular period. The magnetic energy cycles arise from a Lorentz-force feedback on the differential rotation, whereas the processes leading to polarity reversals are more complex, appearing to arise from the interaction of convection with the mean toroidal fields. Moreover, an equatorial migration of toroidal field is found, which is linked to the changing differential rotation, and potentially to a no...

  19. Convective heat transport in geothermal systems

    SciTech Connect (OSTI)

    Lippmann, M.J.; Bodvarsson, G.S.

    1986-08-01T23:59:59.000Z

    Most geothermal systems under exploitation for direct use or electrical power production are of the hydrothermal type, where heat is transferred essentially by convection in the reservoir, conduction being secondary. In geothermal systems, buoyancy effects are generally important, but often the fluid and heat flow patterns are largely controlled by geologic features (e.g., faults, fractures, continuity of layers) and location of recharge and discharge zones. During exploitation, these flow patterns can drastically change in response to pressure and temperature declines, and changes in recharge/discharge patterns. Convective circulation models of several geothermal systems, before and after start of fluid production, are described, with emphasis on different characteristics of the systems and the effects of exploitation on their evolution. Convective heat transport in geothermal fields is discussed, taking into consideration (1) major geologic features; (2) temperature-dependent rock and fluid properties; (3) fracture- versus porous-medium characteristics; (4) single- versus two-phase reservoir systems; and (5) the presence of noncondensible gases.

  20. Magneto-convection in a sunspot umbra

    E-Print Network [OSTI]

    M. Schuessler; A. Voegler

    2006-03-03T23:59:59.000Z

    Results from a realistic simulation of 3D radiative magneto-convection in a strong background magnetic field corresponding to the conditions in sunspot umbrae are shown. The convective energy transport is dominated by narrow upflow plumes with adjacent downflows, which become almost field-free near the surface layers. The strong external magnetic field forces the plumes to assume a cusp-like shape in their top parts, where the upflowing plasma loses its buoyancy. The resulting bright features in intensity images correspond well (in terms of brightness, size, and lifetime) to the observed umbral dots in the central parts of sunspot umbrae. Most of the simulated umbral dots have a horizontally elongated form with a central dark lane. Above the cusp, most plumes show narrow upflow jets, which are driven by the pressure of the piled-up plasma below. The large velocities and low field strengths in the plumes are effectively screened from spectroscopic observation because the surfaces of equal optical depth are locally elevated, so that spectral lines are largely formed above the cusp. Our simulations demonstrate that nearly field-free upflow plumes and umbral dots are a natural result of convection in a strong, initially monolithic magnetic field.

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

    E-Print Network [OSTI]

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

  2. Faculty Positions Department of Earth, Atmospheric, and Planetary Sciences

    E-Print Network [OSTI]

    Kihara, Daisuke

    of hazardous weather phenomena, such as tornadoes, mesoscale convective systems, and winter storms. Climate

  3. JamesCookUniversity (JCU) es la principal universidad australiana en la zona tropical.JCU ofrece excelencia

    E-Print Network [OSTI]

    selva tropical, calentamiento global, turismo, medicina tropical y cuidado de la salud pública. JCU es

  4. Tests of an Ensemble Kalman Filter for Mesoscale and Regional-Scale Data Assimilation. Part III: Comparison with 3DVAR in a Real-Data Case Study

    E-Print Network [OSTI]

    Tests of an Ensemble Kalman Filter for Mesoscale and Regional-Scale Data Assimilation. Part III 8 May 2007) ABSTRACT The feasibility of using an ensemble Kalman filter (EnKF) for mesoscale application of an ensemble Kalman filter (EnKF; Evensen 1994) in the atmospheric sci- ences field (Houtekamer

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

    E-Print Network [OSTI]

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

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

    E-Print Network [OSTI]

    Samelson, Roger

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

  7. Seasonal shift in the foraging niche of a tropical avian resident: resource competition at work?

    E-Print Network [OSTI]

    Jedlicka, J A; Greenberg, R; Perfecto, I; Philpottt, S M; Dietsch, T V

    2006-01-01T23:59:59.000Z

    and migrant birds in Campeche, Mexico. Tropical Ecology 22:a dry tropical forest in Campeche, Mexico and found that

  8. Mesoscale Origin of the Enhanced Cycling-Stability of the Si-Conductive Polymer Anode for Li-ion Batteries

    SciTech Connect (OSTI)

    Gu, Meng; Xiao, Xingcheng; Liu, Gao; Thevuthasan, Suntharampillai; Baer, Donald R.; Zhang, Jiguang; Liu, Jun; Browning, Nigel D.; Wang, Chong M.

    2014-01-14T23:59:59.000Z

    Electrode used in lithium-ion battery is invariably a composite of multifunctional components. The performance of the electrode is controlled by the interactive function of all components at mesoscale. Fundamental understanding of mesoscale phenomenon sets the basis for innovative designing of new materials. Here we report the achievement and origin of a significant performance enhancement of electrode for lithium ion batteries based on Si nanoparticles wrapped with conductive polymer. This new material is in marked contrast with conventional material, which exhibit fast capacity fade. In-situ TEM unveils that the enhanced cycling stability of the conductive polymer-Si composite is associated with mesoscale concordant function of Si nanoparticles and the conductive polymer. Reversible accommodation of the volume changes of Si by the conductive polymer allows good electrical contact between all the particles during the cycling process. In contrast, the failure of the conventional Si-electrode is probed to be the inadequate electrical contact.

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

    SciTech Connect (OSTI)

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

    2008-09-08T23:59:59.000Z

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

  10. Characterization of melting level clouds over the tropical western pacific warm pool

    SciTech Connect (OSTI)

    Jensen, M.; Johnson, K.; Billings, J.; Troyan, D.; Long, C.; Comstock, J.

    2010-03-15T23:59:59.000Z

    A cursory examination of historical ARSCL data indicates a common cloud feature in the tropics are thin detrainment shelves (Attendant Shelf Clouds, or ASCs) near the melting level (see figure for example). We use the ARSCL product to identify ASCs by defining them as cloud layers with bases above 4 km, a corresponding top below 6 km, and a thickness of less than 1 km. In order to prevent biases in determination of the diurnal cycle of cloud occurrence, we require that both the MMCR and MPL are operating well. In this study we use a total of 55 months of data collected over 14 years of deployments at the Manus, Nauru, and Darwin ARM sites in the Tropical Western Pacific to define the frequency of occurrence (~ 14% of the time) and diurnal cycle of these clouds, along with the atmospheric thermodynamic profile. We further investigate the horizontal extent, cloud radiative forcing, and cloud particle phase through a series of “golden cases” where there is a general absence of additional cloud types in the column and nearby deep convection. These cases indicate that the clouds can cover horizontal areas on the order of a GCM gridbox, have significant (but not always) cloud radiative forcing, and may be composed of liquid or ice water.

  11. Transport coefficients of off-lattice mesoscale-hydrodynamics simulation techniques

    E-Print Network [OSTI]

    Hiroshi Noguchi; Gerhard Gompper

    2008-04-14T23:59:59.000Z

    The viscosity and self-diffusion constant of particle-based mesoscale hydrodynamic methods, multi-particle collision dynamics (MPC) and dissipative particle dynamics (DPD), are investigated, both with and without angular-momentum conservation. Analytical results are derived for fluids with an ideal-gas equation of state and a finite-time-step dynamics, and compared with simulation data. In particular, the viscosity is derived in a general form for all variants of the MPC method. In general, very good agreement between theory and simulations is obtained.

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

    E-Print Network [OSTI]

    Patrick B. Warren; Andrey Vlasov

    2014-02-25T23:59:59.000Z

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

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

    E-Print Network [OSTI]

    Kennedy, Charles Joseph

    1987-01-01T23:59:59.000Z

    of Committee) James P. McGuirk (Member) J'ohn M. Klinck (Member) James R. Sco ns (Head of Department) December 1987 ABSTRACT Moist Processes and the Ouasi-Hydrostatic Approximation in a Mesoscale Numerical Model. (December 1987) Charles Joseph...HV)ds' ? gHp s + gHps a dg 1 gt = (gt), s 1 1 (19) the pressure tendency at the model top equation: g f V ~ (pHV)ds' ? VS Vp Q ( el 1 + 0 Yp CpT ? V (H0) ds' )' ? ) (20) Richardson's equation for vertical motion: s f , , f Id d'D &DDVdd ' ? 0 D, 0...

  14. Air convection noise of pencil-beam interferometer for long trace profiler

    E-Print Network [OSTI]

    Yashchuk, Valeriy V.; Irick, Steve C.; MacDowell, Alastair A.; McKinney, Wayne R.; Takacs, Peter Z.

    2006-01-01T23:59:59.000Z

    Air Convection Noise of Pencil-beam Interferometer for Longwe investigate the effect of air convection on laser-beamshown that the NPD spectra due to air convection have a very

  15. Ocean dynamics and thermodynamics in the tropical Indo- Pacific region

    E-Print Network [OSTI]

    Drushka, Kyla

    2011-01-01T23:59:59.000Z

    Pacific Oceans . . . . . . . . . . . . . . . . . . . . . . . . . . . . .in the eastern tropical Pacific Ocean associated with thethe western equatorial Pacific Ocean. J. Geophys. Res. , 96,

  16. Sensitivity of global tropical climate to land surface processes: Mean state and interannual variability

    SciTech Connect (OSTI)

    Ma, Hsi-Yen; Xiao, Heng; Mechoso, C. R.; Xue, Yongkang

    2013-03-01T23:59:59.000Z

    This study examines the sensitivity of global tropical climate to land surface processes (LSP) using an atmospheric general circulation model both uncoupled (with prescribed SSTs) and coupled to an oceanic general circulation model. The emphasis is on the interactive soil moisture and vegetation biophysical processes, which have first order influence on the surface energy and water budgets. The sensitivity to those processes is represented by the differences between model simulations, in which two land surface schemes are considered: 1) a simple land scheme that specifies surface albedo and soil moisture availability, and 2) the Simplified Simple Biosphere Model (SSiB), which allows for consideration of interactive soil moisture and vegetation biophysical process. Observational datasets are also employed to assess the reality of model-revealed sensitivity. The mean state sensitivity to different LSP is stronger in the coupled mode, especially in the tropical Pacific. Furthermore, seasonal cycle of SSTs in the equatorial Pacific, as well as ENSO frequency, amplitude, and locking to the seasonal cycle of SSTs are significantly modified and more realistic with SSiB. This outstanding sensitivity of the atmosphere-ocean system develops through changes in the intensity of equatorial Pacific trades modified by convection over land. Our results further demonstrate that the direct impact of land-atmosphere interactions on the tropical climate is modified by feedbacks associated with perturbed oceanic conditions ("indirect effect" of LSP). The magnitude of such indirect effect is strong enough to suggest that comprehensive studies on the importance of LSP on the global climate have to be made in a system that allows for atmosphere-ocean interactions.

  17. The Relation Between Dry Vortex Merger and Tropical Cyclone Genesis over the Atlantic Ocean

    SciTech Connect (OSTI)

    Chen, Shu-Hua; Liu, Yi-Chin

    2014-10-27T23:59:59.000Z

    A strong, convective African tropical disturbance has a greater chance to develop into a Tropical 23 Depression (TD) if it merges with a shallow, dry vortex (D-vortex) from the north of the African 24 easterly jet (AEJ) after leaving the western coast. Using 11-year reanalysis data we found that the 25 western tip of a vortex strip at northwestern Africa can serve as dry vortices for the D-vortex 26 merger if it shifts southward. Another source of D-vortices is the westward propagating lows 27 along the southern edge of the Saharan air. The D-vortex merger process occurred for 63.5% of 28 tropical cyclones (TCs) or developing systems over the main development region of the Atlantic 29 Ocean, while it occurred for 54% of non-developing systems. TC genesis could be largely 30 controlled by the large-scale environment, but the differences in characteristics of vortices 31 associated with the D-vortex merger between developing and non-developing systems could 32 potentially help determine their destinies; in general, developing systems were dominated by a 33 more intense and moist south vortex, while non-developing systems were dominated by a north 34 vortex which was more intense, drier, and larger in size. Analysis also shows that 74% of intense 35 developing systems were involved with the D-vortex merger process. More attention needs to be 36 paid to the D-vortex merger and the characteristics of those vortices as they can play significant 37 roles or have a strong indication in Atlantic TC genesis.

  18. About convective heat transfer in geothermal systems

    SciTech Connect (OSTI)

    Pashkevich, R.I. [Kamchatsky Complex Department of NIPIgeotherm Institute, Petropavlovsk-Kamchatsky (Russian Federation)

    1996-12-31T23:59:59.000Z

    The interphase fluid-rock heat exchange in convective beat transfer in geothermal systems is investigated Nonlinear model of interphase heat exchange is suggested. Calculation for one dimension case and comparison with known Anzelius-Schumann solution is presented Generalized type block heat transfer model is formulated. The model is adequate for case of geothermal systems and reservoir when a rock block size is comparable with filtration path length. Criterion equations for nonstationary coefficients of interphase heat exchange we presented these equations were obtained in laboratory experiments with diorites.

  19. Natural convection airflow measurement and theory

    SciTech Connect (OSTI)

    Balcomb, J.D.; Jones, G.F.; Yamaguchi, Kenjiro

    1984-01-01T23:59:59.000Z

    Natural convection is a major mechanism for heat distribution in many passive solar buildings, especially those with sunspaces. To better understand this mechanism, observations of air velocities and temperatures have been made in 13 different houses that encompass a wide variety of one- and two-story geometries. This paper extends previous reports. Results from one house are described in detail, and some generalizations are drawn from the large additional mass of data taken. A simple mathematical model is presented that describes the general nature of airflow and energy flow through an aperture.

  20. Improving Convective Parameterization Using ARM Data

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh School footballHydrogenITLaboratory inImproving Convective

  1. Hurricane Earl, September 1, 2010/NOAA Tropical Cyclones

    E-Print Network [OSTI]

    Fang, Yuguang "Michael"

    Hurricane Earl, September 1, 2010/NOAA Tropical Cyclones A PREPAREDNESS GUIDE U.S. DEPARTMENT, 6 of which became hurricanes East Pacific Ocean: 15 tropical storms, 8 of which became hurricanes Central Pacific Ocean: 4 tropical storms, 2 of which became hurricanes Over a typical 2-year period, the U

  2. Species Loss and Aboveground Carbon Storage in a Tropical Forest

    E-Print Network [OSTI]

    Bunker, Daniel E.

    of tropical tree species on carbon storage by simulating 18 possible extinction scenarios within a well-studied 50-hectare tropical forest plot in Panama, which contains 227 tree species. Among extinction as well as the size and longevity of tropical trees. Instead, we simulated species extinctions

  3. LONDON SCHOOL OF HYGIENE & TROPICAL TERMS & CONDITIONS OF BUSINESS

    E-Print Network [OSTI]

    Maizels, Rick

    LONDON SCHOOL OF HYGIENE & TROPICAL MEDICINE TERMS & CONDITIONS OF BUSINESS October 2003 #12 in accordance with these Terms and Conditions; · "School" shall mean the London School of Hygiene & Tropical of Hygiene & Tropical Medicine · "School Purchasing Officer" shall mean the Postholder, Mr Keith Flanders

  4. Malaria Centre London School of Hygiene & Tropical Medicine

    E-Print Network [OSTI]

    Maizels, Rick

    Malaria Centre London School of Hygiene & Tropical Medicine Keppel Street, London, WC1E 7HT, UK October 2014 MalariaCentreReport2012-14LondonSchoolofHygiene&TropicalMedicine #12;#12;Contents Director;2 Director's message London School of Hygiene & Tropical Medicine Despite being preventable and treatable

  5. Investigating Tropical Deforestation Using Two-Stage Spatially Misaligned

    E-Print Network [OSTI]

    Silander Jr., John A.

    Investigating Tropical Deforestation Using Two-Stage Spatially Misaligned Regression Models Deepak Deforestation in the tropics has been a major concern in conservationscience for more than 20 years. Estimates of tropical deforestation over the past few decades have shown an alarming accelerationin forest lost. Concern

  6. ONGOING RESEARCH PROJECTS Model of tropical forest structure and dynamics

    E-Print Network [OSTI]

    Hill, Jeffrey E.

    ONGOING RESEARCH PROJECTS Model of tropical forest structure and dynamics There is a need canopy structure and partitions dynamic rates for a tropical forest on Barro Colorado Island (BCI structure and partitions dynamic rates in a tropical forest. In Review. Journal of Ecology. #12;PPA model

  7. Convective heating analysis of an IFE target in a high temperature, low Reynolds number xenon environment

    E-Print Network [OSTI]

    Holdener, Dain Steffen

    2011-01-01T23:59:59.000Z

    OF THE THESIS Convective Heating Analysis of an IFE Targetto reduce the convective heating to the LEH windows and fuelpoint for more forceful heating simulations, placing less

  8. UNCORRECTED Grid geometry effects on convection in ocean climate models

    E-Print Network [OSTI]

    Kuhlbrodt, Till

    UNCORRECTED PROOF Grid geometry effects on convection in ocean climate models: a conceptual study is the 12 improvement of convection parameterization schemes, but the question of grid geometry also plays to an at- 14 mosphere model. Such ocean climate models have mostly structured, coarsely resolved grids. 15

  9. FLUCTUATIONS NEAR THE CONVECTIVE INSTABILITY IN A CHOLESTERIC LIQUID CRYSTAL

    E-Print Network [OSTI]

    Boyer, Edmond

    . For sufficiently strong heating, it is pos- sible for the buoyancy force to overcome the vis- cous shear forces convective pour une certaine valeur critique. A cause du couplage de modes induit par la force extérieure, la, drives the system into convective instability. It is found that, because of the mode coupling induced

  10. Drainage induced convection rolls in foams (revised version)

    E-Print Network [OSTI]

    Cox, Simon

    , where soap solution is added to the foam at constant flow rate, the irregular motion in the beer glass results for convection in quasi two-dimensional foams (monolayers of bubbles between two glass platesDrainage induced convection rolls in foams (revised version) S. Hutzler, S.J. Cox*, E. Janiaud

  11. Microphysical/mesoscale aspects of nuclear winter and new directions in assessments

    SciTech Connect (OSTI)

    Knox, J.B.

    1985-06-01T23:59:59.000Z

    Recent results of model studies and sensitivity tests have shown the degree to which the intensity and duration of ''nuclear winter'' depends on the mass of soot and dust suspended, its optical properties, its vertical distribution in the atmosphere, and the residence time. The soot from urban fires is viewed as evolving during its dispersion from the early fire induced plumes, to cloud scale systems, to the mesoscale and larger systems. Micro-physical processes are perceived as operating within these systems in a manner to enhance removal from the troposphere, and to alter the verical distribution of the soot or its subsequent, aging or evolving aerosol. Relevant observations and studies of these processes are presented and discussed. Critical inputs to the climate simulation models may well be altered significantly by these process effects, many of which are in need of better definition. Appropriate research needs to be initiated to address and better define these microphysical/mesoscale processes of potential importance in the altered atmospheric system after a major nuclear exchange. 11 refs., 2 figs.

  12. MalariaCentreReport2010-11LondonSchoolofHygiene&TropicalMedicine London School of Hygiene and Tropical Medicine

    E-Print Network [OSTI]

    Maizels, Rick

    MalariaCentreReport2010-11LondonSchoolofHygiene&TropicalMedicine London School of Hygiene Dessens; DTM&H students in laboratory 24 February 2011. Copyright London School of Hygiene & Tropical Publications 114 Members 130 Abbreviations 134 #12;2Director's Message London School of Hygiene & Tropical

  13. Convection, granulation and period jitter in classical Cepheids

    E-Print Network [OSTI]

    Neilson, Hilding R

    2014-01-01T23:59:59.000Z

    Analyses of recent observations of the sole classical Cepheid in the Kepler field, V1154 Cygni, found random changes of about 30 minutes in the pulsation period. These period changes challenge standard theories of pulsation and evolution because the period change is non-secular, and explaining this period jitter is necessary for understanding stellar evolution and the role of Cepheids as precise standard candles. We suggest that convection and convective hot spots can explain the observed period jitter. Convective hot spots alter the timing of flux maximum and minimum in the Cepheid light curve, hence change the measured pulsation period. We present a model of random hot spots that generate a localized flux excess that perturbs the Cepheid light curve and consequently the pulsation period which is consistent with the observed jitter. This result demonstrates how important understanding convection is for modeling Cepheid stellar structure and evolution, how convection determines the red edge of the instability...

  14. Tropical and subtropical cloud transitions in weather and climate prediction models: the GCSS/WGNE Pacific Cross-Section Intercomparison (GPCI)

    SciTech Connect (OSTI)

    Teixeira, J.; Cardoso, S.; Bonazzola, M.; Cole, Jason N.; DelGenio, Anthony D.; DeMott, C.; Franklin, A.; Hannay, Cecile; Jakob, Christian; Jiao, Y.; Karlsson, J.; Kitagawa, H.; Koehler, M.; Kuwano-Yoshida, A.; LeDrian, C.; Lock, Adrian; Miller, M.; Marquet, P.; Martins, J.; Mechoso, C. R.; Meijgaard, E. V.; Meinke, I.; Miranda, P.; Mironov, D.; Neggers, Roel; Pan, H. L.; Randall, David A.; Rasch, Philip J.; Rockel, B.; Rossow, William B.; Ritter, B.; Siebesma, A. P.; Soares, P.; Turk, F. J.; Vaillancourt, P.; Von Engeln, A.; Zhao, M.

    2011-11-01T23:59:59.000Z

    A model evaluation approach is proposed where weather and climate prediction models are analyzed along a Pacific Ocean cross-section, from the stratocumulus regions off the coast of California, across the shallow convection dominated trade-winds, to the deep convection regions of the ITCZ: the GCSS/WGNE Pacific Cross-section Intercomparison (GPCI). The main goal of GPCI is to evaluate, and help understand and improve the representation of tropical and sub-tropical cloud processes in weather and climate prediction models. In this paper, a detailed analysis of cloud regime transitions along the cross-section from the sub-tropics to the tropics for the season JJA of 1998 is presented. This GPCI study confirms many of the typical weather and climate prediction model problems in the representation of clouds: underestimation of clouds in the stratocumulus regime by most models with the corresponding consequences in terms of shortwave radiation biases; overestimation of clouds by the ECMWF Re-Analysis (ERA40) in the deep tropics (in particular) with the corresponding impact in the outgoing longwave radiation; large spread between the different models in terms of cloud cover, liquid water path and shortwave radiation; significant differences between the models in terms of vertical crosssections of cloud properties (in particular), vertical velocity and relative humidity. An alternative analysis of cloud cover mean statistics is proposed where sharp gradients in cloud cover along the GPCI transect are taken into account. This analysis shows that the negative cloud bias of some models and ERA40 in the stratocumulus regions (as compared to ISCCP) is associated not only with lower values of cloud cover in these regimes, but also with a stratocumulus-to-cumulus transition that occurs too early along the trade-wind Lagrangian trajectory. Histograms of cloud cover along the cross-section differ significantly between models. Some models exhibit a quasi-bimodal structure with cloud cover being either very large (close to 100%) or very small, while other models show a more continuous transition. The ISCCP observations suggest that reality is in-between these two extreme examples. These different patterns reflect the diverse nature of the cloud, boundary layer, and convection parameterizations in the participating weather and climate prediction models.

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

    E-Print Network [OSTI]

    Heinemann, Detlev

    the wind energy potential are re- quired. While the European Wind Atlas [3] has been proven to be suitableExperiences with the Application of the Non-Hydrostatic Mesoscale Model GESIMA for assessing Wind.physik.uni-oldenburg.de/ehf *GKSS Research Center Geesthacht, Max-Planck-StraÃ?e 1, D-21494 Geesthacht, Germany To asses wind

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

    E-Print Network [OSTI]

    Kirchner, James W.

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

  17. High-definition analysis of fluid-induced seismicity related to the mesoscale hydromechanical properties of a fault zone

    E-Print Network [OSTI]

    Vallée, Martin

    -strain and seismic measurements taken in the fractured damage zone during the pressurization indicated that seismicity is triggered along low-permeable, highly rigid, low-dip angle, mesoscale-inherited fractures where-so-rigid, aseismic, sub- vertical, fault-related fractures. Using a three-dimensional distinct-element representation

  18. MODIS-Derived Boundary Conditions for a Mesoscale Climate Model: Application to Irrigated Agriculture in the Euphrates Basin

    E-Print Network [OSTI]

    Evans, Jason

    -level water consumption were more than doubled relative to simulations that did not incorporate MODIS data to improve the realism of a regional climate model (the fifth-generation Pennsylvania State University­NCAR Mesoscale Model) with respect to irrigated agriculture. MODIS data were used to estimate spatially

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

    SciTech Connect (OSTI)

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

    2009-08-01T23:59:59.000Z

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

  20. Climate Science: Tropical Expansion by Ocean Swing

    SciTech Connect (OSTI)

    Lu, Jian

    2014-04-01T23:59:59.000Z

    The tropical belt has become wider over the past decades, but climate models fall short of capturing the full rate of the expansion. The latest analysis of the climate simulations suggests that a long-term swing of the Pacific Decadal Oscillation is the main missing cause.