Sample records for tropical convection visiting

  1. 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

  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. 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...

  4. 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

  5. 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

  6. 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

  7. 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.

  8. 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 ...

  9. 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...

  10. 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).

  11. 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.

  12. 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

  13. 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

  14. 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...

  15. 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

  16. 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

  17. 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.

  18. 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.

  19. 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 ...

  20. 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

  1. 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

  2. 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

  3. 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

  4. 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.

  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. 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 ...

  7. 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.

  8. 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...

  9. Plan Your School Visit

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

    Plan Your School Visit For Teachers Teachers Visit the Museum We Visit You Teacher Resources Home Schoolers Plan Your School Visit invisible utility element Plan Your School Visit...

  10. 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...

  11. We Visit You

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

    We Visit You For Teachers Teachers Visit the Museum We Visit You Teacher Resources Home Schoolers Plan Your School Visit invisible utility element We Visit You Science on Wheels:...

  12. When to Visit

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

    When to Visit Plan Your Visit Visit About the Museum Museum Hours Directions & Maps When to Visit Arrange for a Visit Around Los Alamos Contact Us invisible utility element When to...

  13. Arrange for a visit

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

    Arrange for a Visit Plan Your Visit Visit About the Museum Museum Hours Directions & Maps When to Visit Arrange for a Visit Around Los Alamos Contact Us invisible utility element...

  14. 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

  15. 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.

  16. Visiting Dignitaries

    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 SpinPrincetonUsing Maps1 - USAFofEmailNORDUnet,gov Materials areVisiting

  17. Visit Us

    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 1,006 492 742EnergyOnItemResearch >Internship Program TheSite MapScienceVentilation Newss SavannahVisit Us

  18. Visiting CAMS

    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 1,006 492 742EnergyOnItemResearch >Internship Program TheSite MapScienceVentilation Newss SavannahVisit

  19. 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

  20. 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

  1. 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

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. ATLAS Virtual Visits

    E-Print Network [OSTI]

    Goldfarb, Steven; The ATLAS collaboration

    2015-01-01T23:59:59.000Z

    ATLAS Virtual Visits is a project initiated in 2011 for the Education & Outreach program of the ATLAS Experiment at CERN. Its goal is to promote public appreciation of the LHC physics program and particle physics, in general, through direct dialogue between ATLAS physicists and remote audiences. A Virtual Visit is an IP-based videoconference, coupled with a public webcast and video recording, between ATLAS physicists and remote locations around the world, that typically include high school or university classrooms, Masterclasses, science fairs, or other special events, usually hosted by collaboration members. Over the past two years, more than 10,000 people, from all of the world’s continents, have actively participated in ATLAS Virtual Visits, with many more enjoying the experience from the publicly available webcasts and recordings. We present an overview of our experience and discuss potential development for the future.

  12. 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

  13. CAMD Visits Bethany High

    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 3,625govInstrumentstdmadapInactiveVisiting the TWPSuccess Stories Siteandscience, and8 FY0 ByVisits Bethany High

  14. 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...

  15. Home Weatherization Visit

    ScienceCinema (OSTI)

    Chu, Steven

    2013-05-29T23:59:59.000Z

    Secretary Steven Chu visits a home that is in the process of being weatherized in Columbus, OH, along with Ohio Governor Ted Strickland and Columbus Mayor Michael Coleman. They discuss the benefits of weatherization and how funding from the recovery act is having a direct impact in communities across America.

  16. Congressman Clyburn Visit

    ScienceCinema (OSTI)

    Cody, Tom

    2012-06-14T23:59:59.000Z

    Congressman James Clyburn visits the new employees of the Savannah River Site. These new jobs the graduates have received are a result of the Recovery Act at work. Lisa Jackson of the Environmental Protection Agency speaks about how the ARRA is in line with President Obama's vision of a better economy and cleaner environment.

  17. Alien Visitations Close Encounters

    E-Print Network [OSTI]

    Walter, Frederick M.

    Alien Visitations #12;#12;Close Encounters · I: Visual sighting of aerial object (UFO) · II damage · III: Direct observation of extraterrestrials · IV: Abduction #12;UFOs What is a UFO? ·All Sheaffer: http://www.debunker.com/ufo.html #12;#12;#12;Extraordinary Claims Require Extraordinary Evidence

  18. ACADEMIC DELEGATION VISITS 2008 -2014

    E-Print Network [OSTI]

    Di Pillo, Gianni

    ACADEMIC DELEGATION VISITS GRAPHICS 2008 - 2014 #12;Europe: Macedonia, Estonia, Romania, Bosnia, Germany, Estonia, Romania, Turkey, Belarus Asia: Kazakhstan, Russia, Thailand, Japan, Armenia, China, Brazil North America: Mexico, Canada Total Visits: 30 Europe: Czech Republic, Latvia, Germany, Romania

  19. President Obama visits Geothermal Technologies Program Partner...

    Energy Savers [EERE]

    President Obama visits Geothermal Technologies Program Partner President Obama visits Geothermal Technologies Program Partner May 2, 2011 - 1:41pm Addthis President Obama visited...

  20. 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

  1. 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

  2. Visiting Scientists and Researchers

    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 SpinPrincetonUsing Maps1 - USAFofEmailNORDUnet,gov MaterialsVisiting

  3. ARM - Visiting the TWP

    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 3,625govInstrumentstdmadapInactiveVisiting the TWP TWP Related Links Facilities and Instruments Manus Island Nauru

  4. ORISE: Visiting Us

    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 1,006 492 742EnergyOnItemResearch > TheNuclear Astrophysics One of theDedicationOakVisiting Us If you are

  5. When to Visit

    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. DOE Office of ScienceandMesa del SolStrengthening aTurbulenceUtilizeRuraltheWelcomeAnalytics | ArgonneWhen to Visit

  6. Plan Your Visit

    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. DOE Office of Science (SC)IntegratedSpeeding accessPeptoidLabPhysics Physics Oursources |Visit Plan your

  7. Arrange for a Visit

    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 3,625govInstrumentstdmadapInactiveVisiting the TWP TWPAlumni AlumniFederal FacilityAprilAreAround Los Alamos Around

  8. Fermilab | Visit Fermilab | Colloquium

    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. DOE Office of Science (SC) Environmental Assessments (EA)Budget »Travel and Lodging DirectionsSurfaceVisit

  9. NREL: Library - Visiting the Library

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

    Visiting the Library Lending Policy The NREL Library will lend material to outside requesters via their local library's Interlibrary Loan Services. Visitors may not borrow from our...

  10. 2013 PLASTIC SURGERY VISITING PROFESSOR

    E-Print Network [OSTI]

    Shoubridge, Eric

    2013 PLASTIC SURGERY VISITING PROFESSOR Dr. Mutaz B. Habal June 6, 2013 McGill University Division of Plastic Surgery 2013 PLASTIC SURGERY VISITING PROFESSOR Special thanks to our sponsors: Representative: Katherine Marchand Canadian Association of Plastic Surgeons Educational Foundation Division of Plastic

  11. 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;

  12. 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;

  13. 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...

  14. 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

  15. Sandia National Laboratories: Scientific Visit on Crystalline...

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

    WorkshopsScientific Visit on Crystalline Rock Repository Development Scientific Visit on Crystalline Rock Repository Development Many thanks to all participants at the Scientific...

  16. Sandia National Laboratories: 2005 Presidential Visit / Bill...

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

    2005 Presidential Visit Bill Signing ATLAS II Data Acquisition System SandiaKAFB Wind Farm 2005 Presidential Visit Bill Signing On May 18, 2011, in Energy, News, Renewable...

  17. Unclassified Foreign Visits and Assignments

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2004-06-18T23:59:59.000Z

    To define a program for unclassified foreign national access to Department of Energy sites, information, and technologies. This Order cancels DOE P 142.1, Unclassified Foreign Visits and Assignments, dated 7-14-99; DOE N 142.1, Unclassified Foreign Visits and Assignments, dated 7-14-99; Secretarial Memorandum Unclassified Foreign Visits and Assignments, dated 7-14-99; Memorandum from Francis S. Blake, Departmental Use of Foreign Access Central Tracking System, dated 11-05-01; Memorandum from Kyle E. McSlarrow, Interim Guidance for Implementation of the Department's Unclassified Foreign Visits and Assignments Program, dated 12-17-02; and Secretarial Memorandum, Policy Exclusion for Unclassified Foreign National's Access to Department of Energy Facilities in Urgent or Emergency Medical Situations, dated 4-10-01. Cancels: DOE P 142.1 and DOE N 142.1

  18. Unclassified Foreign Visits and Assignments

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    1999-07-14T23:59:59.000Z

    To provide interim Department of Energy (DOE) requirements and responsibilities for unclassified visits and assignment by foreign nationals to DOE facilities for unclassified activities. This Notice supplements DOE P 142.1 dated 7-14-99, which sets overall Departmental policy on unclassified foreign visits and assignments. It is a complement to existing counterintelligence and security orders and policies. DOE N 251.53, dated 05/14/03, extends this directive until canceled. Cancels: DOE 1240.2B

  19. 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

  20. 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...

  1. Unclassified Foreign Visits and Assignments

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    1999-07-14T23:59:59.000Z

    International cooperation and collaboration is an important element in the effective planning and implementation of many Department of Energy (DOE) programs. DOE and its international partners benefit from the exchange of information that results from a managed process of unclassified visits and assignments by foreign nationals. These visits and assignments must be conducted in a manner consistent with U.S. and DOE national security policies, requirements, and objectives including export control laws and regulations. Canceled by DOE O 142.3. Does not cancel other directives.

  2. 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

  3. 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

  4. 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

  5. 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

  6. 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

  7. Classified Visits Involving Foreign Nationals

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2004-01-13T23:59:59.000Z

    The Order establishes a program to manage the Department-wide program to facilitate, document, and assure accountability when approving foreign national access to classified DOE programs and facilities. Cancels portions of Chapter VIII, of DOE O 470.1 that pertain to foreign nationals who visit DOE sitess and require access to classified information. Canceled by DOE O 470.4B.

  8. 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

  9. 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

  10. Estimating visitor and visit numbers to

    E-Print Network [OSTI]

    ............................................ 24 4.5 Monitoring and Evaluating Quality of Life for CRS'07 .......................................25 4.6 Quality of experience visitor, visit and total numbers of visits to woodlands. This document builds on guidance on visitor

  11. Visit

    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 1,006 492 742EnergyOnItemResearch >Internship Program TheSite MapScienceVentilation Newss Savannah

  12. BRAZIL VISITING FELLOWSHIP SCHEME Application Form

    E-Print Network [OSTI]

    Birmingham, University of

    BRAZIL VISITING FELLOWSHIP SCHEME Application Form APPLICATIONS SHOULD BE TYPEWRITTEN AND BOXES of attendance Qualifications awarded and class of Honours, etc. Principal Subject(s) taken #12;BRAZIL VISITING): Date(s) From To To Nature of work and Position held Name and address of employer #12;BRAZIL VISITING

  13. 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

  14. Revisiting the Visit: Understanding How Technology Can Shape the Museum Visit

    E-Print Network [OSTI]

    Grinter, Rebecca Elizabeth

    Revisiting the Visit: Understanding How Technology Can Shape the Museum Visit Rebecca E. Grinter of the current visit, and any museum visiting strategies that the couples had. Finally, we describe how) influenced use. Keywords Electronic guidebook, museum, visitor behavior INTRODUCTION The last few years have

  15. 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

  16. 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.

  17. 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

  18. Math PUrview -- NSF Visiting Professorship for Women

    E-Print Network [OSTI]

    Professor Barbara MacCluer will spend 1994-95 at Purdue as an awardee of a National Science Foundation Visiting Professorship for Women (VPW). As the ...

  19. Jakowski named an EMSL visiting scientist | EMSL

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

    Jakowski named an EMSL visiting scientist Released: March 10, 2015 Enhancing mesoscale computational capabilities in NWChem Jacek Jakowski Jacek Jakowski has been selected...

  20. CAMPUS VISIT AWARD APPLICATION GRADUATE SCHOOL DIVERSITY

    E-Print Network [OSTI]

    Johnston, Daniel

    CAMPUS VISIT AWARD APPLICATION GRADUATE SCHOOL DIVERSITY (MCNAIR, SOUTH TEXAS, WEST TEXAS School Diversity - MCNAIR, SOUTH TEXAS, WEST TEXAS, DIVERSITY MENTORING Fellowship nominees to visit The University of Texas at Austin campus before making a decision on their fellowship offers. The deadline

  1. 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

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. Visiting Database Programmer/Application Developer School of Chemical Sciences

    E-Print Network [OSTI]

    Zimmerman, Steven C.

    Visiting Database Programmer/Application Developer School of Chemical Sciences University professional as Visiting Database Programmer/Application Developer. This position reports to the Information administrative database environment (specifically Oracle and SQL Server). This is a visiting position, but may

  8. 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.

  9. 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.

  10. THURSDAY: Deputy Secretary of Energy to Visit Western Area Power...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    THURSDAY: Deputy Secretary of Energy to Visit Western Area Power Administration Transmission Substation THURSDAY: Deputy Secretary of Energy to Visit Western Area Power...

  11. Site Visit Report, Hanford Waste Encapsulation Storage Facility...

    Energy Savers [EERE]

    Site Visit Report, Hanford Waste Encapsulation Storage Facility - January 2011 Site Visit Report, Hanford Waste Encapsulation Storage Facility - January 2011 January 2011 Hanford...

  12. Vice President Biden Visits National Renewable Energy Laboratory...

    Energy Savers [EERE]

    Vice President Biden Visits National Renewable Energy Laboratory, Announces First Agreement Under "America's Next Top Energy Innovator" Challenge Vice President Biden Visits...

  13. angela merkel visits: Topics by E-print Network

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

    Researchers Physics Websites Summary: at Avalon Photonics T. Asano Visiting Researcher, Sony Corporation J. Hutchinson Visiting Researcher, Intel of Queensland M. Reddy Post...

  14. analysing repeat visitation: Topics by E-print Network

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

    Researchers Physics Websites Summary: at Avalon Photonics T. Asano Visiting Researcher, Sony Corporation J. Hutchinson Visiting Researcher, Intel of Queensland M. Reddy Post...

  15. annual dental visits: Topics by E-print Network

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

    Researchers Physics Websites Summary: at Avalon Photonics T. Asano Visiting Researcher, Sony Corporation J. Hutchinson Visiting Researcher, Intel of Queensland M. Reddy Post...

  16. President Obama Visits the Argonne National Research Lab to Talk...

    Energy Savers [EERE]

    President Obama Visits the Argonne National Research Lab to Talk About American Energy Security President Obama Visits the Argonne National Research Lab to Talk About American...

  17. 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

  18. 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.

  19. 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.

  20. I have just returned from my second visit to China, where I visited with University of

    E-Print Network [OSTI]

    Dahlberg, E. Dan

    and political transforma- tion--heralds a new age not only for China, the world's most populous nation, but also#12;I have just returned from my second visit to China, where I visited with University of the fastest growing in the world--and so is its economy. China is quickly gaining dominance in global markets

  1. 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.

  2. 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.

  3. 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

  4. 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.

  5. 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.

  6. Visit of the Federal President of Germany

    ScienceCinema (OSTI)

    None

    2011-04-25T23:59:59.000Z

    Le D.G. H.Schopper a le plaisir de souhaiter la bienvenue au président de la République fédérale allemande, Richard von Weizsäcker (président féderale de 1984-1994). C'est la première visite d'un président allemand dans l'histoire du Cern.

  7. 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.

  8. 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

  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. Secretary Chu to Visit Houston to Highlight Obama's State of...

    Energy Savers [EERE]

    Visit Houston to Highlight Obama's State of the Union Address, Discuss "All of the Above" Energy Strategy Secretary Chu to Visit Houston to Highlight Obama's State of the Union...

  11. Unclassified Foreign Visits and Assignments Program

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    2004-06-18T23:59:59.000Z

    The order defines a program for unclassified foreign national access to Department of Energy sites, information, and technologies. The page change streamlines the HQs Management Panel review process to include reviews by HSS, IN, and a representative of the cognizant under secretary for access requests involving foreign nationals. Cancels Secretarial Memorandum, Unclassified Foreign Visits and Assignments, dated 7-14-99; Memorandum from Francis S. Blake, Departmental Use of Foreign Access Central Tracking System, dated 11-05-01; Memorandum from Kyle E. McSlarrow, Interim Guidance for Implementation of the Department's Unclassified Foreign Visits and Assignments Program, dated 12-17-02; and Secretarial Memorandum, Policy Exclusion for Unclassified Foreign National's Access to Department of Energy Facilities in Urgent or Emergency Medical Situations, dated 4-10-01. Cancels: DOE P 142.1 and DOE N 142.1

  12. United States-Russia exchange visits

    SciTech Connect (OSTI)

    Desmond, W.J.; Czajkowski, A.F. [USDOE, Washington, DC (United States). Office of Nonproliferation and National Security; Zack, N.R. [Los Alamos National Lab., NM (United States); Martin, H.R. [USDOE New Brunswick Lab., Argonne, IL (United States); Gardner, B. [Sandia National Labs., Albuquerque, NM (United States); Schlegel, S. [Pacific Northwest Lab., Richland, WA (United States); Von Hippel, F. [US Office of Science and Technology Policy, Washington, DC (United States)

    1995-09-01T23:59:59.000Z

    The Department of Energy, under a government-to-government program, hosted the first visit with the Russian Federation to exchange information and technologies for special nuclear material control, accounting, and physical protection at a plutonium storage facility. The Russian specialists toured a storage facility at the Hanford Site near Richland, Washington, and were shown the physical protection and materials control systems that DOE employs to protect excess nuclear materials. Technical discussions included topics associated with protective forces and their operation, perimeter and interior intrusion detection and assessment equipment/systems, vulnerability assessment demonstrations, and the vault monitoring and materials control systems. In October, the Russian Federation hosted a reciprocal visit to the Mayak Enterprise civil plutonium storage facility, previously known as Chelyabinsk-65. The US specialists participated in technical discussions on the protection and control of plutonium and supported an evaluation of safeguards and security at the Mayak storage facility.

  13. 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 ...

  14. 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.

  15. 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...

  16. 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.

  17. 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.

  18. NPT Transparency Visit | National Nuclear Security Administration

    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. DOE Office of Science (SC)Integrated CodesTransparency Visit | National Nuclear Security Administration Facebook

  19. Visit on Cooley | Argonne Leadership Computing Facility

    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. DOE Office of ScienceandMesa del SolStrengthening aTurbulenceUtilize AvailableMedia1.1 The History of theVisionVisit

  20. 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 ...

  1. 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 ...

  2. 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 ...

  3. 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

  4. 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.

  5. 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

  6. 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.

  7. TUESDAY: Energy Secretary Moniz to Visit Los Alamos and Sandia...

    Energy Savers [EERE]

    Energy Secretary Moniz to Visit Los Alamos and Sandia National Laboratories in New Mexico with Senator Udall, Senator Heinrich, and Representative Lujan TUESDAY: Energy...

  8. JLab mourns loss of colleague, visiting scientist Razmik Asaturyan...

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

    after completing assembly and testing. In Memoriam Razmik Asaturyan, 1954 - 2006 CEBAF-Yerevan Collaboration Hall C Visiting Scientist He was only 52 years old. On the...

  9. anniversary public visits: Topics by E-print Network

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

    of Scotland, and the educational effectiveness of its history content for the visiting public Edinburgh, University of - Research Archive Summary: My aim was to investigate the...

  10. Richmond's Kennedy High Visits NERSC- NERSC Center News, Feb...

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

    February 10, 2011 Eighteen students from Richmond's Kennedy High School's TechFutures Academy paid a visit to the National Energy Research Scientific Computing Center (NERSC) at...

  11. 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.

  12. 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.

  13. 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...

  14. 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.

  15. 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.

  16. Fair Nuclear Museum Blank Nanosize Me Camp Visits CHTM

    E-Print Network [OSTI]

    New Mexico, University of

    Fair Nuclear Museum Blank Outreach Nanosize Me Camp Visits CHTM By Stefi Weisburd - July 18, 2013 Campers from the National Museum of Nuclear Science and History's Nanosize Me camp visited CHTM labs and the museum. Students, faculty & staff show Nuclear Museum summer campers nanoscience labs at the Center

  17. Wind, Klickitat, Hood and Fifteen Mile Habitat Site Visits

    E-Print Network [OSTI]

    Wind, Klickitat, Hood and Fifteen Mile Habitat Site Visits April 17-19th, 2013 ISRP Review Team (4 at the Sheraton Airport at 7:15 a.m. Site Visits: Depart airport and head east: Wind, Klickitat, White Salmon in this review: 1998-019-00 Wind River Watershed Underwood Conservation District (UCD), US Forest Service (USFS

  18. 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 ...

  19. 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 ...

  20. 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 ...

  1. 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.

  2. 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...

  3. 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.

  4. 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...

  5. 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.

  6. 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

  7. 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...

  8. 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

  9. 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

  10. 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

  11. 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 ...

  12. 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.

  13. 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.

  14. Visiting senior scientist at Jefferson Lab leads the way on cavity...

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

    Jacek Sekutowicz, visiting senior staff scientist at Jefferson Lab's Institute for Superconducting Radiofrequency Science and Technology Visiting senior scientist at Jefferson Lab...

  15. Energy Secretary to Visit Georgia Nuclear Reactor Site and Tennessee...

    Broader source: Energy.gov (indexed) [DOE]

    D.C. - U.S. Secretary of Energy Secretary Steven Chu will visit the Vogtle nuclear power plant in Waynesboro, Georgia, and Oak Ridge National Laboratory on Wednesday,...

  16. asthma patient visits: Topics by E-print Network

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

    for 10 million school days missed per year S more than any other childhood chronic illness. Asthma accounts for 3 million doctor visits each year. It is the most common 17...

  17. Houston Visit Highlights People and Programs Helping the Office...

    Energy Savers [EERE]

    Its Mission December 4, 2013 - 1:18pm Addthis DOE Deputy Assistant Secretary for Oil and Natural Gas Paula Gant visits GE O&G Customer Collaboration Center in Houston. (L to R -...

  18. 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.

  19. 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

  20. 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

  1. Proceedings of the scientific visit on crystalline rock repository development.

    SciTech Connect (OSTI)

    Mariner, Paul E.; Hardin, Ernest L.; Miksova, Jitka [RAWRA, Czech Republic

    2013-02-01T23:59:59.000Z

    A scientific visit on Crystalline Rock Repository Development was held in the Czech Republic on September 24-27, 2012. The visit was hosted by the Czech Radioactive Waste Repository Authority (RAWRA), co-hosted by Sandia National Laboratories (SNL), and supported by the International Atomic Energy Agency (IAEA). The purpose of the visit was to promote technical information exchange between participants from countries engaged in the investigation and exploration of crystalline rock for the eventual construction of nuclear waste repositories. The visit was designed especially for participants of countries that have recently commenced (or recommenced) national repository programmes in crystalline host rock formations. Discussion topics included repository programme development, site screening and selection, site characterization, disposal concepts in crystalline host rock, regulatory frameworks, and safety assessment methodology. Interest was surveyed in establishing a %E2%80%9Cclub,%E2%80%9D the mission of which would be to identify and address the various technical challenges that confront the disposal of radioactive waste in crystalline rock environments. The idea of a second scientific visit to be held one year later in another host country received popular support. The visit concluded with a trip to the countryside south of Prague where participants were treated to a tour of the laboratory and underground facilities of the Josef Regional Underground Research Centre.

  2. 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

  3. 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

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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

  10. 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

  11. 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.

  12. 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.

  13. 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.

  14. Visit to Darwin Regional Forecasting Centre, 11 April 2012 Drivers of tropical intra-seasonal climate variability

    E-Print Network [OSTI]

    Marshall, Andrew

    -seasonal climate variability: simulation and prediction using POAMA-2 Andrew Marshall Debbie Hudson, Matthew

  15. 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...

  16. 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 ...

  17. 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

  18. 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...

  19. 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...

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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...

  5. 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.

  6. 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.

  7. Housing & other information for international students visiting the CEP

    E-Print Network [OSTI]

    Cosmides, Leda

    Housing & other information for international students visiting the CEP · General information about housing at UCSB: http://www.housing.ucsb.edu/hchoices/cho-general-info.htm · Housing tips for international students: http://www.housing.ucsb.edu/hchoices/international-tips.htm · Housing placement

  8. Visit us online for updates! www.eucenter.wisc.edu

    E-Print Network [OSTI]

    Scharer, John E.

    Visit us online for updates! www.eucenter.wisc.edu Events at a Glance European Union Center: EUCE 4.16.2013 4:00pm, Wisconsin Idea Room, 159 Education Building Wiemer Salverda, "Inequalities at UW-Madison) 4.18.2013 2:00pm,245 Education Building, 1000 Bascom Mall Jutta Allmendinger

  9. Hanford/Tomsk reciprocal site visit: Plutonium agreement compliance talks

    SciTech Connect (OSTI)

    Libby, R.A.; Sorenson, R.; Six, D.; Schiegel, S.C.

    1994-11-01T23:59:59.000Z

    The objective of the visit to Hanford Site was to: demonstrate equipment, technology, and methods for calculating Pu production, measuring integrated reactor power, and storing and safeguarding PuO{sub 2}; demonstrate the shutdown of Hanford production reactors; and foster openness and transparency of Hanford operations. The first day`s visit was an introduction to Hanford and a review of the history of the reactors. The second day consisted of discussions on the production reactors, reprocessing operations, and PuO{sub 2} storage. The group divided on the third day to tour facilities. Group A toured the N reactor, K-West reactor, K-West Basins, B reactor, and participated in a demonstration and discussion of reactor modeling computer codes. Group B toured the Hanford Pu Storage Facility, 200-East Area, N-cell (oxide loadout station), the Automated Storage Facility, and the Nondestructive Assay Measurement System. Group discussions were held during the last day of the visit, which included scheduling of a US visit to Russia.

  10. Re-Visiting Health Informatics What is Health Informatics?

    E-Print Network [OSTI]

    Abidi, Syed Sibte Raza

    and the quality of care Facilitate remote healthcare at a patient's home #12;What do Health Informaticians DoRe-Visiting Health Informatics HINF1100 Fall 2008 #12;What is Health Informatics? · Health the effective organization, analysis, management and use of health information to improve the delivery

  11. Visite du navire ocanographique Bilan de la campagne scientifique AWA

    E-Print Network [OSTI]

    du Maroc. Les scientifiques issus de ces pays données à bord du navire. La visite guidée du navire Sénégal, en présence d d'Allemagne, de la Belgique, du Cap-Vert, de la Guinée Bissau, du Royaume du Maroc

  12. 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

  13. 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

  14. 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.

  15. 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

  16. 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

  17. Girl Scouts USA CEO visits ORNL to discuss STEM programs | ornl...

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

    -4165 Girl Scouts USA CEO visits ORNL to discuss STEM programs Anna Maria Chavez, middle, CEO of the Girl Scouts USA, visits the Center for Computational Sciences Jan. 30 with two...

  18. 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,

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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

  4. Bees visiting squash (Cucurbita moschata Duchesne ex Poiret) in southwestern Colombia (Hymenoptera: Apoidea)

    E-Print Network [OSTI]

    Zambrano-G, Giselle; Gonzalez, Victor H.; Hinojosa-Dí az, Ismael A.; Engel, Michael S.

    2013-10-07T23:59:59.000Z

    , southwestern Colombia. Two further bee species are also recorded from a crop visited in the Department of Huila...

  5. Review of the US Department of Energy Classified Visits Program

    SciTech Connect (OSTI)

    Martin, S W; Killinger, M H; Segura, M A

    1992-07-01T23:59:59.000Z

    This review examines the US Department of Energy (DOE) Classified Visits Program, which is administered by the Office of Safeguards and Security. The overall purpose of this analysis is to (1) ensure that DOE policy and implementing procedures are appropriate to maintain US national security intentions; (2) evaluate the effectiveness of the process used across the DOE complex; and (3) recommend changes which will enhance the overall efficiency of the process while maintaining the program's integrity.

  6. Department of Defense Benchmarks VPP in Visit to Hanford

    Broader source: Energy.gov [DOE]

    Representatives of the Department of Defense's (DoD's) Voluntary Protection Program Center of Excellence (VPP-CX) are working to meet a safety and health goal established by Secretary of Defense Donald Rumsfeld to reduce injuries at DoD sites nationwide. In order to accomplish this goal, DoD visited the Department of Energy's (DOE's) Hanford Site in southeast Washington State on December 12, 2005, to learn about its exemplary safety programs and benchmark the site's VPP effort.

  7. 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

  8. 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

  9. 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

  10. 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

  11. 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

  12. 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

  13. Supporting museum co-visits using mobile devices Yann Laurillau, Fabio Patern

    E-Print Network [OSTI]

    Supporting museum co-visits using mobile devices Yann Laurillau, Fabio Paternò Consiglio Nazionale learning in museum visits and show an example application based on mobile palmtop systems. To this end, we, such as museums. The museum visit is usually an individual experience. Furthermore, electronic guides

  14. VISITING COMMITTEE ON ADVANCED TECHNOLOGY National Institute of Standards and Technology

    E-Print Network [OSTI]

    VISITING COMMITTEE ON ADVANCED TECHNOLOGY National Institute of Standards and Technology 2007 Annual Report Visiting Committee on Advanced Technology of the National Institute of Standards and Technology U.S. Department of Commerce March 3, 2008 #12;VISITING COMMITTEE ON ADVANCED TECHNOLOGY National

  15. VISITING COMMITTEE ON ADVANCED TECHNOLOGY National Institute of Standards and Technology

    E-Print Network [OSTI]

    VISITING COMMITTEE ON ADVANCED TECHNOLOGY National Institute of Standards and Technology 1 2009 Annual Report Visiting Committee on Advanced Technology (VCAT) of the National Institute of Standards and Technology U.S. Department of Commerce March 3, 2010 #12;VISITING COMMITTEE

  16. A Model for Predicting Daily Peak Visitation and Implications for Recreation Management and Water Quality: Evidence

    E-Print Network [OSTI]

    carrying capacity. Keywords Visitation model Á Recreation management Á Water quality Á River visitation ÁA Model for Predicting Daily Peak Visitation and Implications for Recreation Management and Water Quality: Evidence from Two Rivers in Puerto Rico Luis E. Santiago � Armando Gonzalez-Caban � John Loomis

  17. Please visit our web site: w3.pppl.gov/CEMM The Center for Extended

    E-Print Network [OSTI]

    Please visit our web site: w3.pppl.gov/CEMM The Center for Extended Magnetohydrodynamic Modeling APDEC #12;Please visit our web site: w3.pppl.gov/CEMM We have had (and are having) a very productive, etc.), and many journal papers #12;Please visit our web site: w3.pppl.gov/CEMM All the presentations

  18. 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

  19. 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...

  20. 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

  1. 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

  2. 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

  3. 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

  4. 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

  5. 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...

  6. 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.

  7. 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.

  8. Oceanic Origins of Southwest Tropical Atlantic Biases

    E-Print Network [OSTI]

    Xu, Zhao

    2013-05-03T23:59:59.000Z

    Oceanic General Circulation Model POP Parallel Ocean Program ROMS Regional Ocean Modeling System SEC South Equatorial Current SECC South Equatorial Counter Current SETA Southeast Tropical Atlantic SEUC South Equatorial UnderCurrent SLP Sea Level... SST bias ................................................................................... 5 1.3.2 SST bias in SETA ...................................................................................... 8 1.4 Objectives and Approach...

  9. 6, 1064910672, 2006 Extinction in tropical

    E-Print Network [OSTI]

    (Stephens et al., 1990). The radiative influence of a given cirrus cloud depends mostly on the delicate balance between its albedo effect and its greenhouse effect. The dominant effect is globally unknownACPD 6, 10649­10672, 2006 Extinction in tropical ice clouds from lidar, Nephelometer V. Noel et al

  10. The development of convective instability in relation to convective activity and synoptic systems in AVE IV

    E-Print Network [OSTI]

    Davis, James Gregory

    1979-01-01T23:59:59.000Z

    700 mb 500 mb 300 mb 100 mb 1. 8 2 54 3. 1' 6. 2 3. 8 5 64 7 5 15. 0 RMS Direction Error RNS ~Seed Error -1 -1 0. 5ms l. oms -1 -1 0. 8 m s 2. 0 m s -1 -1 10ms 3. 8ms -1 -1 2. 0 m s 5. 7 m s The rawinsonde data were supplemented by hourly... of Co ttee) 4' (Member) N. I (Member) (Head of Department) August 1979 ABSTRACT Tha Development of Convective Instability in Relation to ConVectiVe Activity and Synoptic Systems in AVE 1V, (August 1979$ James Gregory Davis, B. S. , Texas A&M...

  11. Minister Sophia Aggelonitis Visits the Gilbrea Centre for Studies in Aging Minister Sophia Aggelonitis, Minister Responsible for Seniors and Minister of Revenue, visited

    E-Print Network [OSTI]

    Thompson, Michael

    Minister Sophia Aggelonitis Visits the Gilbrea Centre for Studies in Aging Minister Sophia. Sophia Aggelonitis, MPP Hamilton Mountain (centre) visits the Gilbrea Centre for Studies in Aging. Pictured with Sophia is Dr. Margaret Denton, Director, Gilbrea Centre for Studies in Aging (left

  12. EM Leaders Visit Employees at Moab Site | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't Your Destiny:RevisedAdvisory Board Contributions EM Highlights AdvisoryLeaders Visit Employees

  13. Congressional Delegation visits Naval Reactors Facility | National Nuclear

    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 3,625govInstrumentstdmadapInactiveVisiting theCommercialization andComputerConfirmed: Stellar Behemoth

  14. Energy Secretary Steven Chu Visits Oak Ridge | Department of Energy

    Office of Environmental Management (EM)

    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 1,006 492 742 33 1112011 Strategic Plan Departmentof EnergyPublic Law of| Department ofMake MajorVisits Oak

  15. DOE secretary stresses energy security during Los Alamos visit

    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 3,625govInstrumentstdmadapInactiveVisitingContract Management Fermi SitePARTOffice ofHale Plan by(formerlyand

  16. Defense Secretary Chuck Hagel visits Sandia | National Nuclear Security

    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 3,625govInstrumentstdmadapInactiveVisitingContract Management FermiDavid Turner David3 | NationalSUBSCRIBE:|

  17. Investor and entrepreneur visits Los Alamos for open coffee

    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. DOE Office of Science (SC)Integrated Codes | NationalCurriculum IntroductionInvestor and entrepreneur visits

  18. Admiral Haney visits New Mexico labs | National Nuclear Security

    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 3,625govInstrumentstdmadapInactiveVisiting the TWP TWP Related LinksATHENAAdministrative ContactsAdministration New

  19. Admiral Haney visits Pantex | National Nuclear Security Administration

    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 3,625govInstrumentstdmadapInactiveVisiting the TWP TWP Related LinksATHENAAdministrative ContactsAdministration

  20. Sandia Energy - Energy Council Executive Committee Visits Sandia

    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. DOE Office of Scienceand RequirementsCoatingsUltra-High-Voltage SiliconEnergy Council Executive Committee Visits

  1. Visiting Speaker Program - July 24, 2009 | Department of Energy

    Office of Environmental Management (EM)

    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 1,006 492 742 33 1112011 Strategic2Uranium TransferonUS-IndiaVALUE STUDY4, 2009 Visiting Speaker Program - July

  2. Visiting Speaker Program - July 28, 2010 | Department of Energy

    Office of Environmental Management (EM)

    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 1,006 492 742 33 1112011 Strategic2Uranium TransferonUS-IndiaVALUE STUDY4, 2009 Visiting Speaker Program - July8,

  3. Visiting NETL Albany, Morgantown or Pittsburgh | netl.doe.gov

    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. DOE Office of ScienceandMesa del SolStrengthening aTurbulenceUtilize AvailableMedia1.1 The HistoryVisiting NETL

  4. WEDNESDAY: Energy Secretary Moniz to Visit National Renewable Energy

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnual Siteof Energy 2, 2015Visiting Strong, Smart, and BoldDepartmentManufacturingLaboratory in

  5. Planetary scientist to discuss Curiosity rover's visit to Mars

    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. DOE Office of Science (SC)IntegratedSpeeding accessPeptoidLabPhysics Physics Oursources |Visit Plan

  6. Ars Technica Visits GE's China Technology Center | GE Global Research

    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 3,625govInstrumentstdmadapInactiveVisiting the TWP TWPAlumni AlumniFederal FacilityAprilAreAround Los Alamos

  7. Energy Innovation Hub Directors Visit the Hill | Department of Energy

    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 3,625govInstrumentstdmadapInactiveVisitingContractElectron-StateEnergyHeavy DutyDistrict |Consumption Survey

  8. Secretary Chu Visits Japanese Embassy | Department of Energy

    Office of Environmental Management (EM)

    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 1,006 492 742 33Frequently AskedEnergy SmallImplementing J-F-1Department ofSecretaryTokmanVisits Japanese

  9. Convective effects in a regulatory and proposed fire model

    SciTech Connect (OSTI)

    Wix, S.D. [GRAM, Inc., Albuquerque, NM (United States); Hohnstreiter, G.F. [Sandia National Labs., Albuquerque, NM (United States). Transportation System Development Dept.

    1995-12-31T23:59:59.000Z

    Radiation is the dominant mode of heat transfer in large fires. However, convection can be as much as 10 to 20 percent of the total heat transfer to an object in a large fire. The current radioactive material transportation packaging regulations include convection as a mode of heat transfer in the accident condition scenario. The current International Atomic Energy Agency Safety Series 6 packaging regulation states ``the convection coefficient shall be that value which the designer can justify if the package were exposed to the specified fire``. The current Title 10, Code of Federal Regulations, Part 71 (10CFR71) packaging regulation states ``when significant, convection heat input must be included on the basis of still, ambient air at 800{degrees}C (1475{degrees}F)``. Two questions that can arise in an analysts mind from an examination of the packaging regulations is whether convection is significant and whether convection should be included in the design analysis of a radioactive materials transportation container. The objective of this study is to examine the convective effects on an actual radioactive materials transportation package using a regulatory and a proposed thermal boundary condition.

  10. Numerical and Experimental Modeling of Natural Convection for a Cryogenic Prototype of a Titan

    E-Print Network [OSTI]

    Colonius, Tim

    in Sutherland's law D = diameter g = gravitation acceleration h = convection coefficient k = thermal

  11. Convective heat transfer characteristics of China RP-3 aviation kerosene at supercritical pressure

    E-Print Network [OSTI]

    Guo, Zhixiong "James"

    Convective heat transfer characteristics of China RP-3 aviation kerosene at supercritical pressure Keywords: Supercritical pressure Aviation kerosene Convective heat transfer Numerical study a b s t r a c convective in kerosene pipe flow is complicated. Here the convective heat transfer characteristics of China

  12. PHYSICS OF FLUIDS 25, 044105 (2013) Onset of buoyancy-driven convection in Cartesian

    E-Print Network [OSTI]

    Firoozabadi, Abbas

    2013-01-01T23:59:59.000Z

    the onset of buoyancy-driven convection relevant to subsurface carbon dioxide sequestration in confined

  13. ADVANCED TROPICAL METEOROLOGY: METR 5453.001 T R 11:30-12:45, NWC 5820

    E-Print Network [OSTI]

    Droegemeier, Kelvin K.

    and their limitations. - Why study the tropics separately? Examples of major tropical circulations on weather. - Easterly waves. 5. Tropical Cyclones What are they? How do they differ from extratropical cyclones cyclones: operations and research. - Predictability aspects of tropical cyclones. - Tropical cyclones

  14. On the connection between continental-scale land surface processes and the tropical climate in a coupled ocean-atmosphere-land system

    E-Print Network [OSTI]

    Ma, H-Y; Mechoso, CR; Xue, Y; Xiao, H; Neelin, JD; Ji, X

    2013-01-01T23:59:59.000Z

    the remote response to the convective heating in Africa, weand remote regions. The convective heating anomalies

  15. VARIATION OF STELLAR ENVELOPE CONVECTION AND OVERSHOOT WITH METALLICITY

    SciTech Connect (OSTI)

    Tanner, Joel D.; Basu, Sarbani; Demarque, Pierre [Department of Astronomy, Yale University, P.O. Box 208101, New Haven, CT 06520-8101 (United States)] [Department of Astronomy, Yale University, P.O. Box 208101, New Haven, CT 06520-8101 (United States)

    2013-04-10T23:59:59.000Z

    We examine how metallicity affects convection and overshoot in the superadiabatic layer of main sequence stars. We present results from a grid of three-dimensional radiation hydrodynamic simulations with four metallicities (Z = 0.040, 0.020, 0.010, 0.001), and spanning a range in effective temperature (4950 < T{sub eff} < 6230). We show that changing the metallicity alters properties of the convective gas dynamics, and the structure of the superadiabatic layer and atmosphere. Our grid of simulations shows that the amount of superadiabaticity, which tracks the transition from efficient to inefficient convection, is sensitive to changes in metallicity. We find that increasing the metallicity forces the location of the transition region to lower densities and pressures, and results in larger mean and turbulent velocities throughout the superadiabatic region. We also quantify the degree of convective overshoot in the atmosphere, and show that it increases with metallicity as well.

  16. Overshooting Convection from High-resolution NEXRAD Observations

    E-Print Network [OSTI]

    Solomon, David

    2014-01-09T23:59:59.000Z

    of the Rocky Mountains. Overshooting convection is most common over the high plains, and there is a pronounced seasonal and diurnal cycle present. The majority of overshooting systems occur during the warm season, and a diurnal maximum of overshooting occurs...

  17. Theory for induced convection experiments in the tokamak edge

    E-Print Network [OSTI]

    Theory for induced convection experiments in the tokamak edge P. Helander1 , D.D. Ryutov2 , and R National Laboratory, Livermore, USA By biasing alternate divertor plates in a tokamak, one can create

  18. atmospheric convective boundary: Topics by E-print Network

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

    convective conditions is found to be primarily due to variations in mixed layer wind speed. Low-level winds thus play the major role in regulating the ability of thermals to...

  19. Experimental Investigation of Natural Convection in Trombe Wall Systems

    E-Print Network [OSTI]

    Chen, B.; Zhao, J.; Chen, C.; Zhuang, Z.

    2006-01-01T23:59:59.000Z

    In this paper, experiments with a passive solar building with Trombe wall in the north cold climate are carried out and discussed, and the natural convection heat transfer process has been investigated. The relativity of the factors affecting indoor...

  20. Identification of Robust Terminal-Area Routes in Convective Weather

    E-Print Network [OSTI]

    Balakrishnan, Hamsa

    Convective weather is responsible for large delays and widespread disruptions in the U.S. National Airspace System, especially during summer. Traffic flow management algorithms require reliable forecasts of route blockage ...

  1. Effects of aerosols on deep convective cumulus clouds

    E-Print Network [OSTI]

    Fan, Jiwen

    2009-05-15T23:59:59.000Z

    This work investigates the effects of anthropogenic aerosols on deep convective clouds and the associated radiative forcing in the Houston area. The Goddard Cumulus Ensemble model (GCE) coupled with a spectral-bin microphysics is employed...

  2. Identification of Robust Routes using Convective Weather Forcasts

    E-Print Network [OSTI]

    Michalek, Diana

    Convective weather is responsible for large delays and widespread disruptions in the U.S. National Airspace System (NAS), especially during summer months when travel demand is high. This has been the motivation for Air ...

  3. Survey and evaluation of techniques to augment convective heat transfer

    E-Print Network [OSTI]

    Bergles A. E.

    1965-01-01T23:59:59.000Z

    This report presents a survey and evaluation of the numerous techniques which have been shown to augment convective heat transfer. These techniques are: surface promoters, including roughness and treatment; displaced ...

  4. NATURAL CONVECTION IN PASSIVE SOLAR BUILDINGS: EXPERIMENTS, ANALYSIS AND RESULTS

    E-Print Network [OSTI]

    Gadgil, Ashok; Bauman, Fred; Kammerud, Ronald

    2008-01-01T23:59:59.000Z

    effect of the adjacent conditioned zones was properly accounted for by the BLASTeffects of this observation on the accuracy of results from the programs, the convection code was used iteratively with BLAST

  5. Interaction between surface and atmosphere in a convective boundary layer /

    E-Print Network [OSTI]

    Garai, Anirban

    2013-01-01T23:59:59.000Z

    of cold fluid constitute most of the heat transport andevent cold air descends to the ground, heat transport fromcold air during sweep events. The convective boundary layer has a great influence on moisture transport,

  6. Land-atmosphere interaction and radiative-convective equilibrium

    E-Print Network [OSTI]

    Cronin, Timothy (Timothy Wallace)

    2014-01-01T23:59:59.000Z

    I present work on several topics related to land-atmosphere interaction and radiative-convective equilibrium: the first two research chapters invoke ideas related to land-atmosphere interaction to better understand ...

  7. NATURAL CONVECTION IN PASSIVE SOLAR BUILDINGS: EXPERIMENTS, ANALYSIS AND RESULTS

    SciTech Connect (OSTI)

    Gadgil, A.; Bauman, F.; Kammerud, R.

    1981-04-01T23:59:59.000Z

    Computer programs have been developed to numerically simulate natural convection in two- and three-dimensional room geometries. The programs have been validated using published data from the literature, results from a full-scale experiment performed at the Massachusetts Institute of Technology, and results from a small-scale experiment performed at LBL. One of the computer programs has been used to study the influence of natural convection on the thermal performance of a single zone in a direct-gain passive solar building. It is 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. This study implies that the building heating loads calculated by standard building energy analysis methods may have substantial errors as a result of their use of common assumptions regarding the convection processes which occur in an enclosure.

  8. 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

  9. Vertical convection in neutrino-dominated accretion flows

    E-Print Network [OSTI]

    Liu, Tong; Kawanaka, Norita; Li, Ang

    2015-01-01T23:59:59.000Z

    We present the effects of the vertical convection on the structure and luminosity of the neutrino-dominated accretion flow (NDAF) around a stellar-mass black hole in spherical coordinates. We found that the convective energy transfer can suppress the radial advection in the NDAF, and that the density, temperature and opening angle are slightly changed. As a result, the neutrino luminosity and annihilation luminosity are increased, which is conducive to achieve the energy requirement of gamma-ray bursts.

  10. Possible solar cycle variations in the convection zone

    E-Print Network [OSTI]

    Sarbani Basu; H. M. Antia

    2000-01-26T23:59:59.000Z

    Using data from the Global Oscillations Network Group (GONG) that covers the period from 1995 to 1998 we study the change in frequencies of solar oscillations with solar activity. From these frequencies we attempt to determine any possible variation in solar structure with solar activity. We do not find any evidence of a change in the convection zone depth or extent of overshoot below the convection zone during the solar cycle.

  11. A numerical study of orographic effects on moist convection

    E-Print Network [OSTI]

    Smith, Robert Doyle

    1972-01-01T23:59:59.000Z

    based on a typical synoptic situation across the mountain range of northern Honshu, Japan. Wind shear, stability~ and moisture were varied from the basic situation to observe the effects of induced vertical motion on the different clouds which formed... forecaster in Japan. Convective systems were noted as they crossed the Sea oi' Japan and changes to these systems ovserved as they crossed the mountain ranges of Japan. Some convective systems would move across the Sea of Japan caus1ng consecutive reports...

  12. Natural convection airflow and heat transport in buildings: experimental results

    SciTech Connect (OSTI)

    Balcomb, J.D.; Jones, G.F.

    1985-01-01T23:59:59.000Z

    Observations of natural convection airflow in passive solar buildings are described. Particular results are given for two buildings supplementing other data already published. A number of generalizations based on the monitoring of the 15 buildings are presented. It is concluded that energy can be reasonably well distributed throughout a building by natural convection provided suitable openings are present and that the direction of heat transport is either horizontally across or upward.

  13. Natural convection heat transfer within horizontal spent nuclear fuel assemblies

    SciTech Connect (OSTI)

    Canaan, R.E.

    1995-12-01T23:59:59.000Z

    Natural convection heat transfer is experimentally investigated in an enclosed horizontal rod bundle, which characterizes a spent nuclear fuel assembly during dry storage and/or transport conditions. The basic test section consists of a square array of sixty-four stainless steel tubular heaters enclosed within a water-cooled rectangular copper heat exchanger. The heaters are supplied with a uniform power generation per unit length while the surrounding enclosure is maintained at a uniform temperature. The test section resides within a vacuum/pressure chamber in order to subject the assembly to a range of pressure statepoints and various backfill gases. The objective of this experimental study is to obtain convection correlations which can be used in order to easily incorporate convective effects into analytical models of horizontal spent fuel systems, and also to investigate the physical nature of natural convection in enclosed horizontal rod bundles in general. The resulting data consist of: (1) measured temperatures within the assembly as a function of power, pressure, and backfill gas; (2) the relative radiative contribution for the range of observed temperatures; (3) correlations of convective Nusselt number and Rayleigh number for the rod bundle as a whole; and (4) correlations of convective Nusselt number as a function of Rayleigh number for individual rods within the array.

  14. Thermal effects of Kohout convection in the Bahamas and Florida

    SciTech Connect (OSTI)

    Simms, M.A.

    1985-01-01T23:59:59.000Z

    Kohout convection is a low-temperature groundwater thermal convection process in carbonate platform margins. It was first conceived of and postulated to occur in the subsurface of Florida by Francis Kohout in the 1960's. The flow is driven by buoyancy arising from subsurface differences in salinity and in temperature. Cold, dense seawater surrounding a platform at depth migrates inward, displacing warmer pore waters at the same elevation. This inflowing density current is in turn warmed within the platform and is buoyed upward to discharge on the platform shelf or margin resulting in a giant convective half-cell. In isolated platforms, such as the Bahamas, temperature differences alone drive Kohout convection. In Florida, the regional meteoric flow of the Floridan Aquifer mixes by dispersion with the convecting seawater resulting in an enhanced flow rate. Approximate analytical and numerical solutions of the governing differential equations allow the interactions of the flow and temperature fields to be determined. Permeability characteristics and platform margin geometry are the principal controls of the thermal structure and groundwater flow pattern in isolated platforms. In Florida, regional flow strength is also a control. High horizontal permeabilities (100 md to 1 darcy and higher) and tall, steep margins (1 km height, 30/sup 0/ slope) allow Kohout convection to penetrate 30 to 50 km inland causing substantial cooling. It may thus be a control of thermal evolution of the Florida-Bahamas Basin as well as parts of other sedimentary basins.

  15. Relationships between tropical cyclone intensity and satellite based indicators of inner core convection: 85 GHz ice scattering signature and lightning

    E-Print Network [OSTI]

    Cecil, Daniel Joseph

    1997-01-01T23:59:59.000Z

    -1' radius minimum PCT and lightning in Hurricane Felix. . . . . 48 22 Hurricane Luis best track, 12 UTC 27 August - 0 UTC 11 September 1995. . . ?50 23 Luis 85 GHz PCT iield at 0748 V TC 29 August 1995. . . . . . 57 24 Luis OTD lightning observations... at 2348 UTC 28 August 1995. . . . . 25 Luis 85 GHz PCT field at 0905 UTC 30 August 1995. . . . 54 26 Luis 85 GHz PCT field at 2017 UTC 31 August 1995. . . . . . . . 27 Luis 85 GHz PCT field at 0841 UTC 2 September 1995. . . . 28 Luis 85 GHz PCT field...

  16. 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...

  17. Insights into the historical construction of species-rich Mesoamerican seasonally dry tropical forests: the diversification

    E-Print Network [OSTI]

    Olson, Mark

    Insights into the historical construction of species-rich Mesoamerican seasonally dry tropical, Mesoamerica, niche conservatism, seasonally dry tropical forests. Summary · Mesoamerican arid biomes epitomize the vast species richness of Meso- american seasonally dry tropical forests (SDTFs), and to evaluate

  18. Carbon sequestration potential of tropical pasture compared with afforestation in Panama

    E-Print Network [OSTI]

    Potvin, Catherine

    Carbon sequestration potential of tropical pasture compared with afforestation in Panama S E B) to estimate the carbon sequestration potential of tropical pasture compared with afforestation; and (3 show the potential for considerable carbon sequestration of tropical afforestation and highlight

  19. GCM simulation of the tropical mixing barriers in the lower stratosphere

    E-Print Network [OSTI]

    Hu, Yongyun

    1996-01-01T23:59:59.000Z

    The high-resolution SKYHI general circulation model is used to simulate tropical mixing behavior and to investigate mixing barriers in the tropical lower stratosphere. Results show that during the solstitial seasons a tropical weak-mixing zone...

  20. australian tropical savannas: Topics by E-print Network

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

    results in warmer and drier climate of tropical savannas increases temperatures and wind speeds and decreases precipitation and relative humidity Jackson, Robert B. 2...

  1. Ocean Barrier Layers’ Effect on Tropical Cyclone Intensification

    SciTech Connect (OSTI)

    Balaguru, Karthik; Chang, P.; Saravanan, R.; Leung, Lai-Yung R.; Xu, Zhao; Li, M.; Hsieh, J.

    2012-09-04T23:59:59.000Z

    Improving a tropical cyclone's forecast and mitigating its destructive potential requires knowledge of various environmental factors that influence the cyclone's path and intensity. Herein, using a combination of observations and model simulations, we systematically demonstrate that tropical cyclone intensification is significantly affected by salinity-induced barrier layers, which are 'quasi-permanent' features in the upper tropical oceans. When tropical cyclones pass over regions with barrier layers, the increased stratification and stability within the layer reduce storm-induced vertical mixing and sea surface temperature cooling. This causes an increase in enthalpy flux from the ocean to the atmosphere and, consequently, an intensification of tropical cyclones. On average, the tropical cyclone intensification rate is nearly 50% higher over regions with barrier layers, compared to regions without. Our finding, which underscores the importance of observing not only the upper-ocean thermal structure but also the salinity structure in deep tropical barrier layer regions, may be a key to more skillful predictions of tropical cyclone intensities through improved ocean state estimates and simulations of barrier layer processes. As the hydrological cycle responds to global warming, any associated changes in the barrier layer distribution must be considered in projecting future tropical cyclone activity.

  2. Energy saving strategies with personalized ventilation in tropics

    E-Print Network [OSTI]

    Schiavon, Stefano; Melikov, Arsen; Chandra Sekhar, Chandra Sekhar

    2010-01-01T23:59:59.000Z

    of a personalized ventilation system in the tropics, in:edged-mounted task ventilation system, Indoor Air, Vol. 14 (a chair-based personalized ventilation system, Building and

  3. Clarence Strait Tidal Energy Project, Tenax Energy Tropical Tidal...

    Open Energy Info (EERE)

    Test Centre, Jump to: navigation, search 1 Retrieved from "http:en.openei.orgwindex.php?titleClarenceStraitTidalEnergyProject,TenaxEnergyTropicalTidalTestCentre,&o...

  4. Characterization of Trapped Lignin-Degrading Microbes in Tropical...

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

    to cellulose, which is critical for biofuels production. Tropical rain forest soils in Puerto Rico are characterized by frequent anoxic conditions and fluctuating redox,...

  5. "A New Paradigm for Secondary Eyewall Formation in Tropical Cyclones...

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

    Road Princeton, NJ 08540-6649 "A New Paradigm for Secondary Eyewall Formation in Tropical Cyclones", Chun-Chieh Wu (National Taiwan University) Contact Information Website: Website...

  6. TROPICAL DEFORESTATION MODELLING: A COMPARATIVE ANALYSIS OF DIFFERENT PREDICTIVE APPROACHES.

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    TROPICAL DEFORESTATION MODELLING: A COMPARATIVE ANALYSIS OF DIFFERENT PREDICTIVE APPROACHES-time discretisation; Remote Sensing; Neural Networks; Markov Chains; MCE; Dinamica; Risk management; Deforestation

  7. DOE Deputy Secretary and Rosatom Director Visit Y-12, Oak Ridge...

    National Nuclear Security Administration (NNSA)

    Deputy Secretary and Rosatom Director Visit Y-12, Oak Ridge National Laboratory During Frist Meeting of US-Russian Nuclear Energy and Nuclear Security Working Group | National...

  8. Emergency Department Frequent User: Pilot Study of Intensive Case Management to Reduce Visits and Computed Tomography

    E-Print Network [OSTI]

    Grover, Casey A; Close, Reb JH; Villarreal, Kathy; Goldman, Lee M

    2010-01-01T23:59:59.000Z

    33. Brenner DJ, Hall EJ. Computed tomography – an increasingReduce Visits and Computed Tomography Casey A. Grover* Rebof total images in all computed tomography (CT) scans during

  9. Acknowledgements These articles above are based on visits to the following sites, among others

    E-Print Network [OSTI]

    Keniston, Kenneth

    Acknowledgements These articles above are based on visits to the following sites, among others Pradesh, Karnataka, Maharastra, and Haryana. #12;Acknowledgements 2 Many friends have helped me throughout

  10. Direct numerical simulations of convective heat transfer

    SciTech Connect (OSTI)

    Pointel, G.; Acharya, S.; Sharma, C. [Louisiana State Univ., Baton Rouge, LA (United States). Mechanical Engineering Dept.

    1996-11-01T23:59:59.000Z

    This paper deals with the development of a direct numerical simulation (DNS) code for solving the incompressible Navier-Stokes equation using higher order finite difference schemes. The time dependent Navier Stokes equation has been discretized using semi-implicit second order time splitting scheme, which requires the solution of pressure Poisson equation. For this purpose a Galerkin Fourier transform in the spanwise direction and a matrix diagonalization technique is used. The convection terms are formulated in non-conservative form on a collocated grid. A fifth order upwind biased scheme is used for this purpose. Diffusion terms are differenced using a sixth order central difference scheme. The algorithm is implemented on the MasPar MP-1, a Single Instruction Multiple Data computer where efficient data parallelization is used to get DNS results. The code has been used to get results for smooth channel flow at Re{sub {tau}} = 180. Results are now being obtained for the energy equation and for flow in a periodic ribbed channel.

  11. EVIDENCE FOR CONVECTION IN SUNSPOT PENUMBRAE

    SciTech Connect (OSTI)

    Bharti, L.; Solanki, S. K.; Hirzberger, J., E-mail: bharti@mps.mpg.d [Max-Planck-Institute fuer sonnensystemforschung, Max-Planck-Str. 2, 37191 Katlenburg-Lindau (Germany)

    2010-10-20T23:59:59.000Z

    We present an analysis of twisting motions in penumbral filaments in sunspots located at heliocentric angles from 30{sup 0} to 48{sup 0} using three time series of blue continuum images obtained by the Broadband Filter Imager (BFI) on board Hinode. The relations of the twisting motions to the filament brightness and the position within the filament and within the penumbra, respectively, are investigated. Only certain portions of the filaments show twisting motions. In a statistical sense, the part of the twisting portion of a filament located closest to the umbra is brightest and possesses the fastest twisting motion, with a mean twisting velocity of 2.1 km s{sup -1}. The middle and outer sections of the twisting portion of the filament (lying increasingly further from the umbra), which are less bright, have mean velocities of 1.7 km s{sup -1} and 1.35 km s{sup -1}, respectively. The observed reduction of brightness and twisting velocity toward the outer section of the filaments may be due to reducing upflow along the filament's long axis. No significant variation of twisting velocity as a function of viewing angles was found. The obtained correlation of brightness and velocity suggests that overturning convection causes the twisting motions observed in penumbral filament and may be the source of the energy needed to maintain the brightness of the filaments.

  12. Dynamic Transitions of Surface Tension Driven Convection

    E-Print Network [OSTI]

    Henk Dijkstra; Taylan Sengul; Shouhong Wang

    2011-05-05T23:59:59.000Z

    We study the well-posedness and dynamic transitions of the surface tension driven convection in a three-dimensional (3D) rectangular box with non-deformable upper surface and with free-slip boundary conditions. It is shown that as the Marangoni number crosses the critical threshold, the system always undergoes a dynamic transition. In particular, two different scenarios are studied. In the first scenario, a single mode losing its stability at the critical parameter gives rise to either a Type-I (continuous) or a Type-II (jump) transition. The type of transitions is dictated by the sign of a computable non-dimensional parameter, and the numerical computation of this parameter suggests that a Type-I transition is favorable. The second scenario deals with the case where the geometry of the domain allows two critical modes which possibly characterize a hexagonal pattern. In this case we show that the transition can only be either a Type-II or a Type-III (mixed) transition depending on another computable non-dimensional parameter. We only encountered Type-III transition in our numerical calculations. The second part of the paper deals with the well-posedness and existence of global attractors for the problem.

  13. Tropical Pacific nutrient dynamics in the modern and pleistocene ocean : insights from the nitrogen isotope system

    E-Print Network [OSTI]

    Rafter, Patrick Anthony

    2009-01-01T23:59:59.000Z

    eastern tropical North Pacific Ocean, Mar. Chem. , 3, 271–eastern tropical South Pacific Ocean, Mar. Chem. , 16, 277–and N 2 fixation in the Pacific Ocean, Global Biogeochem.

  14. A Large Eddy Simulation of Turbulent Compressible Convection: Differential Rotation in the Solar Convection Zone

    E-Print Network [OSTI]

    Francis J. Robinson; Kwing L. Chan

    2000-11-21T23:59:59.000Z

    We present results of two simulations of the convection zone, obtained by solving the full hydrodynamic equations in a section of a spherical shell. The first simulation has cylindrical rotation contours (parallel to the rotation axis) and a strong meridional circulation, which traverses the entire depth. The second simulation has isorotation contours about mid-way between cylinders and cones, and a weak meridional circulation, concentrated in the uppermost part of the shell. We show that the solar differential rotation is directly related to a latitudinal entropy gradient, which pervades into the deep layers of the convection zone. We also offer an explanation of the angular velocity shear found at low latitudes near the top. A non-zero correlation between radial and zonal velocity fluctuations produces a significant Reynolds stress in that region. This constitutes a net transport of angular momentum inwards, which causes a slight modification of the overall structure of the differential rotation near the top. In essence, the {\\it thermodynamics controls the dynamics through the Taylor-Proudman momentum balance}. The Reynolds stresses only become significant in the surface layers, where they generate a weak meridional circulation and an angular velocity `bump'.

  15. Influence of the tropical Atlantic versus the tropical Pacific on Caribbean rainfall

    E-Print Network [OSTI]

    . Taylor Department of Physics, University of the West Indies, Mona, Jamaica David B. Enfield Physical); KEYWORDS: Caribbean, rainfall, El Nin~o, tropical Atlantic, warm pool, model Citation: Taylor, M. A., D. B the two equatorial oceanic basins. Oppositely signed SST anomalies in the NINO3 region and the central

  16. Predicting travel costs for recreational visits at aquatic sites within the Caribbean National Forest using GIS

    E-Print Network [OSTI]

    1 Predicting travel costs for recreational visits at aquatic sites within the Caribbean National to visit various recreation sites. Cost surface models, developed in a GIS, can estimate the amount' predictive capabilities. The GIS models were then used to estimate the travel costs associated

  17. PRINCETON UNIVERSITY ART MUSEUM Small group visits to the Art Museum can...

    E-Print Network [OSTI]

    PRINCETON UNIVERSITY ART MUSEUM Small group visits to the Art Museum can... ...Hone visual literacy, Lights, Camera, Action (FRS 110), to the Museum to apply lessons learned about how the eye sees via a module at the Art Museum on French Impressionist art. They first visit the Museum together

  18. VISITING COMMITTEE ON ADVANCED TECHNOLOGY National Institute of Standards and Technology

    E-Print Network [OSTI]

    VISITING COMMITTEE ON ADVANCED TECHNOLOGY National Institute of Standards and Technology FY 2006 Annual Report U.S. Department of Commerce Technology Administration National Institute of Standards and Technology #12;VISITING COMMITTEE ON ADVANCED TECHNOLOGY National Institute of Standards and Technology

  19. NORWAY-SOUTH AFRICA RESEARCH PROJECT TPCP/CTHB STUDENTS VISIT NORWAY

    E-Print Network [OSTI]

    NORWAY-SOUTH AFRICA RESEARCH PROJECT TPCP/CTHB STUDENTS VISIT NORWAY Recently two masters' students of visiting Norway to work with the Norwegian Forestry Research Institute (Skogforsk) in Ã?s. This opportunity arose from a bilateral agreement between the Governments of Norway and South Africa. For Gilbert

  20. Stay protected when connected Visit security.duke.edu for more information.

    E-Print Network [OSTI]

    McShea, Daniel W.

    Stay protected when connected Visit security.duke.edu for more information. Follow these guidelines Visit security.duke.edu for more information. Follow these tips for securing mobile devices: iOS 6/software/. Windows Mac Another free option: Microsoft Security Essentials: http://windows.microsoft.com/en- US/windows/products/security

  1. Chapter Number1 Biomass Prediction in Tropical Forests:2

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Chapter Number1 Biomass Prediction in Tropical Forests:2 The Canopy Grain Approach3 Christophe France9 1. Introduction10 The challenging task of biomass prediction in dense and heterogeneous tropical different forest structures may indeed present similar above ground biomass (AGB) values.13 This is probably

  2. Facts about ENSO: . Originates in the tropical Pacific

    E-Print Network [OSTI]

    : . Computer models show skill in forecasting tropical Pacific Ocean temperatures one to two years in advance for Pacific Ocean observations that are the foundation of skillful ENSO forecasts: Moored buoys Drifting buoysaaaaaa Facts about ENSO: . Originates in the tropical Pacific . Has a periodicity of 2­7 years

  3. What is a Hurricane? Tropical system with maximum sustained

    E-Print Network [OSTI]

    Meyers, Steven D.

    Andrew-Category 4· Category 4 Hurricane - Winds 131-155 mph. Wall failures in homes and complete roofHurricane 101 #12;What is a Hurricane? · Tropical system with maximum sustained surface wind of 74 mph or greater. A hurricane is the worst and the strongest of all tropical systems. · Also known

  4. The Maslov dequantization, idempotent and tropical mathematics: A brief introduction

    E-Print Network [OSTI]

    G. L. Litvinov

    2005-07-01T23:59:59.000Z

    This paper is a brief introduction to idempotent and tropical mathematics. Tropical mathematics can be treated as a result of the so-called Maslov dequantization of the traditional mathematics over numerical fields as the Planck constant $\\hbar$ tends to zero taking imaginary values.

  5. Proximate Population Factors and Deforestation in Tropical Agricultural Frontiers

    E-Print Network [OSTI]

    Lopez-Carr, David

    Proximate Population Factors and Deforestation in Tropical Agricultural Frontiers David L. Carr are significantly associated at the global and regional scales, evidence for population links to deforestation of thought on population­environment theories relevant to deforestation in tropical agricultural frontiers

  6. ORIGINAL PAPER Formulation of a tropical town energy budget

    E-Print Network [OSTI]

    Ribes, Aurélien

    ORIGINAL PAPER Formulation of a tropical town energy budget (t-TEB) scheme Hugo Abi Karam & Augusto /Accepted: 18 August 2009 # Springer-Verlag 2009 Abstract This work describes the tropical town energy) as observed in the Metropolitan Area of Rio de Janeiro (MARJ; -22° S; -44° W) in Brazil. Reasoning about

  7. Carbon accumulation of tropical peatlands over millennia: a modeling approach

    E-Print Network [OSTI]

    in the global carbon cycle by storing about 40­90 Gt C in peat. Over the past several decades, tropical with lowering the water table and peat burning, releasing large amounts of carbon stored in peat the Holocene Peat Model (HPM), which has been successfully applied to northern temperate peatlands. Tropical

  8. The iron nutrition of tropical foliage plants

    E-Print Network [OSTI]

    Lang, Harvey Joe

    1986-01-01T23:59:59.000Z

    extraction of Fe from fresh leaves proved to be a good indicator of the Fe status of plants. It consistently gave higher correlations with chlorophyll concentration than other methods tested. Conversely, total Fe analysis on dried leaves did not always... resolve the correct Fe status of the plant. The studies also suggested that P and the ratio of P/0. 1 N HC1-Fe may be important parameters in the diagnosis of Fe status. In a screening of 11 tropical foliage plants, Ficus benj ami ha and Nephroiepi...

  9. UPDATE: Tropical Storm Isaac | Department of Energy

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directed off Energy.gov. Are you sureReportsofDepartmentSeries | Department ofDepartmentChinaUPDATE: Tropical

  10. ARM - Lesson Plans: 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: National5Sales for4,645 3,625govInstrumentstdmadap Documentation TDMADAP : XDC documentationBarrow, Alaska OutreachMakingPastSurfaceTheTropical

  11. 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...

  12. 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...

  13. Efficient small-scale dynamo in solar convection zone

    E-Print Network [OSTI]

    Hotta, H; Yokoyama, T

    2015-01-01T23:59:59.000Z

    We investigate small-scale dynamo action in the solar convection zone through a series of high resolution MHD simulations in a local Cartesian domain with 1$R_\\odot$ (solar radius) of horizontal extent and a radial extent from 0.715 to 0.96$R_\\odot$. The dependence of the solution on resolution and diffusivity is studied. For a grid spacing of less than 350 km, the root mean square magnetic field strength near the base of the convection zone reaches 95% of the equipartition field strength (i.e. magnetic and kinetic energy are comparable). For these solutions the Lorentz force feedback on the convection velocity is found to be significant. The velocity near the base of the convection zone is reduced to 50% of the hydrodynamic one. In spite of a significant decrease of the convection velocity, the reduction in the enthalpy flux is relatively small, since the magnetic field also suppresses the horizontal mixing of the entropy between up- and downflow regions. This effect increases the amplitude of the entropy pe...

  14. Visualizations, Screen Shots, and Data Input Files from VisIT

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

    VisIt is a free interactive parallel visualization and graphical analysis tool for viewing scientific data on Unix and PC platforms. Users can quickly generate visualizations from their data, animate them through time, manipulate them, and save the resulting images for presentations. VisIt contains a rich set of visualization features so that you can view your data in a variety of ways. It can be used to visualize scalar and vector fields defined on two- and three-dimensional (2D and 3D) structured and unstructured meshes. VisIt was designed to handle very large data set sizes in the terascale range and yet can also handle small data sets in the kilobyte range. The VisIT website provides a gallery of vizualizations, another set of screen shots, and allows downloads of data files for input and source codes and executables for the VisIT software suite.

  15. Trip report for field visit to Fayetteville Shale gas wells.

    SciTech Connect (OSTI)

    Veil, J. A.; Environmental Science Division

    2007-09-30T23:59:59.000Z

    This report describes a visit to several gas well sites in the Fayetteville Shale on August 9, 2007. I met with George Sheffer, Desoto Field Manager for SEECO, Inc. (a large gas producer in Arkansas). We talked in his Conway, Arkansas, office for an hour and a half about the processes and technologies that SEECO uses. We then drove into the field to some of SEECO's properties to see first-hand what the well sites looked like. In 2006, the U.S. Department of Energy's (DOE's) National Energy Technology Laboratory (NETL) made several funding awards under a program called Low Impact Natural Gas and Oil (LINGO). One of the projects that received an award is 'Probabilistic Risk-Based Decision Support for Oil and Gas Exploration and Production Facilities in Sensitive Ecosystems'. The University of Arkansas at Fayetteville has the lead on the project, and Argonne National Laboratory is a partner. The goal of the project is to develop a Web-based decision support tool that will be used by mid- and small-sized oil and gas companies as well as environmental regulators and other stakeholders to proactively minimize adverse ecosystem impacts associated with the recovery of gas reserves in sensitive areas. The project focuses on a large new natural gas field called the Fayetteville Shale. Part of the project involves learning how the natural gas operators do business in the area and the technologies they employ. The field trip on August 9 provided an opportunity to do that.

  16. ARM - Midlatitude Continental Convective Clouds (comstock-hvps)

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

    Jensen, Mike; Comstock, Jennifer; 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. Eects of thermo-chemical mantle convection on the thermal evolution of the Earth's core

    E-Print Network [OSTI]

    Tackley, Paul J.

    E¡ects of thermo-chemical mantle convection on the thermal evolution of the Earth's core Takashi in the core with a fully dynamic thermo-chemical mantle convection model is developed to investigate

  18. 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 ...

  19. Forced-convection surface-boiling heat transfer and burnout in tubes of small diameters

    E-Print Network [OSTI]

    Bergles A. E.

    1962-01-01T23:59:59.000Z

    A basic heat-transfer apparatus was designed and constructed for the study of forced-convection boiling in small channels. The various regions of forced-convection surface boiling were studied experimentally and analytically. ...

  20. The influence of convective activity on the vorticity budget 

    E-Print Network [OSTI]

    Townsend, Tamara L

    1987-01-01T23:59:59.000Z

    . Continued. ~E' i~ QE I ~ tt Jtm a tt NE v~ l / tmt ta' NE ~~f IIIY G NE~~ NE a/+ NE NE NE NE 1st NE Fig. 13. Radar summary for 1435 GNT 10 Apri. l 1979. NE I l. c I E j~7 ~ NE NE MP- Qo+ Fig. 14. Radar summary for 2235 GMT 10 April 1979... experiment. 15 3 Average values of terms in the vorticity equation for a convective (Area 1) and a nonconvective (Area 2) area during AVE VII. Units of 10 s 145 4 Average values of terms in the vorticity equation for a convective (Area 1) and a...

  1. Midlatitude Continental Convective Clouds Experiment (MC3E)

    SciTech Connect (OSTI)

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

    2010-04-01T23:59:59.000Z

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

  2. Calculus Cheat Sheet Visit http://tutorial.math.lamar.edu for a complete set of Calculus notes. 2005 Paul Dawkins

    E-Print Network [OSTI]

    Bogaerts, Steven

    Calculus Cheat Sheet Visit http://tutorial.math.lamar.edu for a complete set of Calculus notes;Calculus Cheat Sheet Visit http://tutorial.math.lamar.edu for a complete set of Calculus notes. © 2005 Paul

  3. On the Wavelength of the Rossby Waves Radiated by Tropical Cyclones KYLE D. KROUSE

    E-Print Network [OSTI]

    Sobel, Adam

    of tropical cyclones; the theory then predicts the zonal separation distance of such tropical cyclone pairsOn the Wavelength of the Rossby Waves Radiated by Tropical Cyclones KYLE D. KROUSE Department cyclone (TC). In some cases, such disturbances undergo tropical cyclogenesis, resulting in a pair

  4. Submitted to Geophysical and Astrophysical Fluid Dynamics Shear and Mixing in Oscillatory Doubly Di usive Convection

    E-Print Network [OSTI]

    Paparella, Francesco

    convection are found in the Earth's oceans, most notably, below the polar ice caps. There melting ice

  5. The ionospheric signature of transient dayside reconnection and the associated pulsed convection return ow

    E-Print Network [OSTI]

    Boyer, Edmond

    of convection. Key words. Ionosphere (plasma convection) á Magne- tospheric physics (magnetopause, cusp, 1996, and references therein) and the excitation of dayside convection is the focus of the present of magnetosheath plasma into the magneto- sphere, and the ionospheric plasma ¯ow at the footprint of the cusp

  6. 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

  7. weber, evans, moser, and newell Air Traffic Management Decision Support During Convective Weather

    E-Print Network [OSTI]

    Reuter, Martin

    · weber, evans, moser, and newell Air Traffic Management Decision Support During Convective WeatherTraffic Management Decision Support During Convective Weather Mark E. Weber, James E. Evans, William R. Moser algorithm. #12;· weber, evans, moser, and newell Air Traffic Management Decision Support During Convective

  8. 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

  9. 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

  10. Tropical Cloud Properties and Radiative Heating Profiles

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

    Mather, James

    We have generated a suite of products that includes merged soundings, cloud microphysics, and radiative fluxes and heating profiles. The cloud microphysics is strongly based on the ARM Microbase value added product (Miller et al., 2003). We have made a few changes to the microbase parameterizations to address issues we observed in our initial analysis of the tropical data. The merged sounding product is not directly related to the product developed by ARM but is similar in that it uses the microwave radiometer to scale the radiosonde column water vapor. The radiative fluxes also differ from the ARM BBHRP (Broadband Heating Rate Profile) product in terms of the radiative transfer model and the sampling interval.

  11. Does convective aggregation need to be represented in cumulus parameterizations?

    E-Print Network [OSTI]

    Does convective aggregation need to be represented in cumulus parameterizations? Isabelle Tobin,1 in phenomena such as ``hot spots'' or the Madden-Julian Oscillation. These findings support the need climate models lack any such representation. The ability of a cloud system- resolving model to reproduce

  12. NATURAL CONVECTION OF SUBCOOLED LIQUID NITROGEN IN A VERTICAL CAVITY

    E-Print Network [OSTI]

    Chang, Ho-Myung

    temperature superconductor) power devices, such as HTS transformers, fault current limiters, and terminals power transformer cooled by natural convection of subcooled liquid nitrogen. A liquid nitrogen bath of subcooled liquid nitrogen system for an HTS transformer, operating at around 65 K. This system consists

  13. Sparse grid collocation schemes for stochastic natural convection problems

    E-Print Network [OSTI]

    Zabaras, Nicholas J.

    stochastic methods and Monte-Carlo based sam- pling methods are two approaches that have been used to analyzeSparse grid collocation schemes for stochastic natural convection problems Baskar on the Smolyak algorithm offers a viable alternate method for solving high-dimensional stochastic partial

  14. Convection venting lensed reflector-type compact fluorescent lamp system

    DOE Patents [OSTI]

    Pelton, B.A.; Siminovitch, M.

    1997-07-29T23:59:59.000Z

    Disclosed herein is a fluorescent lamp housing assembly capable of providing convection cooling to the lamp and the ballast. The lens of the present invention includes two distinct portions, a central portion and an apertured portion. The housing assembly further includes apertures so that air mass is able to freely move up through the assembly and out ventilation apertures. 12 figs.

  15. Convection venting lensed reflector-type compact fluorescent lamp system

    DOE Patents [OSTI]

    Pelton, Bruce A. (825 Manor Rd., El Sobrante, CA 94803); Siminovitch, Michael (829 Manor Rd., El Sobrante, CA 94803)

    1997-01-01T23:59:59.000Z

    Disclosed herein is a fluorescent lamp housing assembly capable of providing convection cooling to the lamp and the ballast. The lens of the present invention includes two distinct portions, a central portion and an apertured portion. The housing assembly further includes apertures so that air mass is able to freely move up through the assembly and out ventilation apertures.

  16. EFFECTS OF SURFACE DEPRESSION AND CONVECTION IN GTA WELDING

    E-Print Network [OSTI]

    Eagar, Thomas W.

    EFFECTS OF SURFACE DEPRESSION AND CONVECTION IN GTA WELDING M.L. Lin, T.W. Eagar Materials of the weld pool which are changed by these fact ors . It is shown that, at current s in excess of 300 amperes in a different heat distribution on the weld pool surface . ALTHOUGH THE GAS tungsten arc (GTA) welding process

  17. Estimation of Convection Loss from Paraboloidal Dish Cavity Receivers

    E-Print Network [OSTI]

    In general, cavity receivers employed in the sun-tracking paraboloidal dish concentrator are subjected the numerical investigation of natural and combined convection loss from cavity receivers employed in solar is a significant source of energy loss from thermal receivers used with dish solar concentrators. This paper

  18. Modeling thermal convection in supradetachment basins: example from western Norway

    E-Print Network [OSTI]

    Andersen, Torgeir Bjørge

    Modeling thermal convection in supradetachment basins: example from western Norway A. SOUCHE*, M. DABROWSKI AND T. B. ANDERSEN Physics of Geological Processes (PGP), University of Oslo, Oslo, Norway basins of western Norway are examples of supradetachment basins that formed in the hanging wall

  19. 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...

  20. The CHUVA Project how does convection vary across the Brazil?

    E-Print Network [OSTI]

    Chaboureau, Jean-Pierre

    1 The CHUVA Project ­ how does convection vary across the Brazil? Luiz A. T. Machado1 , Maria A. F de Previsão de Tempo e Estudos Climáticos (CPTEC), Brazil. 2. Universidade de São Paulo. Instituto de Astronomia, Geofísica e Ciências Atmosféricas, Brazil. 3. Departamento de Ciências e Tecnologia Espacial

  1. Symmetrybreaking instabilities of convection By A.M. Rucklidge

    E-Print Network [OSTI]

    Rucklidge, Alastair

    fluid layer is often modelled by considering a finite box with periodic boundary conditions in the two­dimensional convection in a plane layer of unit depth with periodic boundary conditions with equal wave numbers k oscillatory solutions are cre­ ated in a Hopf bifurcation. One of the three oscillations, alternating

  2. 'Butterfly effect' in porous Bénard convection heated from below

    SciTech Connect (OSTI)

    Siri, Z.; Liew, K. Y. [Institute of Mathematical Sciences, University of Malaya, 50603 Kuala Lumpur (Malaysia); Ibrahim, R. I. [Faculty of Science and Technology, Universiti Sains Islam Malaysia, 71800 Bandar Baru Nilai, Negeri Sembilan Darul Khusus (Malaysia)

    2014-07-10T23:59:59.000Z

    Transition from steady to chaos for the onset of Bénard convection in porous medium was analyzed. The governing equation is reduced to ordinary differential equation and solved using built in MATLAB ODE45. The transition from steady to chaos take over from a limit cycle followed by homoclinic explosion.

  3. Preparation, Biodistribution and Neurotoxicity of Liposomal Cisplatin following Convection Enhanced

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Preparation, Biodistribution and Neurotoxicity of Liposomal Cisplatin following Convection Enhanced delivery (CED) to F98 glioma bearing rats. Neurotoxicologic studies were carried out in non-tumor bearing. Unexpectedly, LipoplatinTM was highly neurotoxic when given i.c. by CED and resulted in death immediately

  4. Stellar Surface Convection, Line Asymmetries, and Wavelength Shifts

    E-Print Network [OSTI]

    , Box 43, SE­22100 Lund, Sweden Abstract. Wavelength positions of photospheric absorption lines may the sinking and cooler (darker) gas. For the Sun, the effect is around 300 m s \\Gamma1 , expected to increase), and intergranular lanes with local redshifts (sinking motion), as naturally expected in convective energy transfer

  5. Predicting flow reversals in chaotic natural convection using data assimilation

    E-Print Network [OSTI]

    Danforth, Chris

    . The thermosyphon, a type of natural convection loop or non-mechanical heat pump, can be likened to a toy model of climate. Thermosyphons are used in solar water heaters (Belessiotis and Mathiou- lakis, 2002), cooling) and other industrial applications. In these heat pumps, buoyant forces move fluid through a closed loop

  6. Nonequilibrium pattern formation and spatiotemporal chaos in fluid convection

    SciTech Connect (OSTI)

    Michael Cross

    2006-09-13T23:59:59.000Z

    The final report for grant number DE-FG03-98ER14891 summarizes the application of the unique simulation capabilities developed under DOE support to investigations of important issues in pattern formation and spatiotemporal chaos in Rayleigh-Benard convection, particularly emphasizing quantitative contact with the active experimental programs.

  7. OSCILLATORY FLOW FORCED CONVECTION IN MICRO HEAT SPREADERS

    E-Print Network [OSTI]

    Beskok, Ali

    transfer devices, micro heat pipes, based on capillary pumping of a multiphase ¯uid in microchannels, have-phase forced convection heat transfer and ¯ow characteristics of water in microchannels, both in the laminar) concept for ef cient transport of large, concentrated heat loads is introduced. The MHS is a single

  8. Transport of Magnetic Fields in Convective, Accreting Supernova Cores

    E-Print Network [OSTI]

    Christopher Thompson; Norman Murray

    2001-05-24T23:59:59.000Z

    We consider the amplification and transport of a magnetic field in the collapsed core of a massive star, including both the region between the neutrinosphere and the shock, and the central, opaque core. An analytical argument explains why rapid convective overturns persist within a newly formed neutron star for roughly 10 seconds ($> 10^3$ overturns), consistent with recent numerical models. A dynamical balance between turbulent and magnetic stresses within this convective layer corresponds to flux densities in excess of $10^{15}$G. Material accreting onto the core is heated by neutrinos and also becomes strongly convective. We compare the expected magnetic stresses in this convective `gain layer' with those deep inside the neutron core. Buoyant motions of magnetized fluid are greatly aided by the intense neutrino flux. We calculate the transport rate through a medium containing free neutrons protons, and electrons, in the limiting cases of degenerate or non-degenerate nucleons. Fields stronger than $\\sim 10^{13}$ G are able to rise through the outer degenerate layers of the neutron core during the last stages of Kelvin-Helmholtz cooling (up to 10 seconds post-collapse), even though these layers have become stable to convection. We also find the equilibrium shape of a thin magnetic flux rope in the dense hydrostatic atmosphere of the neutron star, along with the critical separation of the footpoints above which the rope undergoes unlimited expansion against gravity. The implications of these results for pulsar magnetism are summarized, and applied to the case of late fallback over the first 1,000-10,000 s of the life of a neutron star

  9. Study of Multi-Scale Cloud Processes Over the Tropical Western Pacific Using Cloud-Resolving Models Constrained by Satellite Data

    SciTech Connect (OSTI)

    Dudhia, Jimy

    2013-03-12T23:59:59.000Z

    Clouds in the tropical western Pacific are an integral part of the large scale environment. An improved understanding of the multi-scale structure of clouds and their interactions with the environment is critical to the ARM (Atmospheric Radiation Measurement) program for developing and evaluating cloud parameterizations, understanding the consequences of model biases, and providing a context for interpreting the observational data collected over the ARM Tropical Western Pacific (TWP) sites. Three-dimensional cloud resolving models (CRMs) are powerful tools for developing and evaluating cloud parameterizations. However, a significant challenge in using CRMs in the TWP is that the region lacks conventional data, so large uncertainty exists in defining the large-scale environment for clouds. This project links several aspects of the ARM program, from measurements to providing improved analyses, and from cloud-resolving modeling to climate-scale modeling and parameterization development, with the overall objective to improve the representations of clouds in climate models and to simulate and quantify resolved cloud effects on the large-scale environment. Our objectives will be achieved through a series of tasks focusing on the use of the Weather Research and Forecasting (WRF) model and ARM data. Our approach includes: -- Perform assimilation of COSMIC GPS radio occultation and other satellites products using the WRF Ensemble Kalman Filter assimilation system to represent the tropical large-scale environment at 36 km grid resolution. This high-resolution analysis can be used by the community to derive forcing products for single-column models or cloud-resolving models. -- Perform cloud-resolving simulations using WRF and its nesting capabilities, driven by the improved regional analysis and evaluate the simulations against ARM datasets such as from TWP-ICE to optimize the microphysics parameters for this region. A cirrus study (Mace and co-authors) already exists for TWP-ICE using satellite and ground-based observations. -- Perform numerical experiments using WRF to investigate how convection over tropical islands in the Maritime Continent interacts with large-scale circulation and affects convection in nearby regions. -- Evaluate and apply WRF as a testbed for GCM cloud parameterizations, utilizing the ability of WRF to run on multiple scales (from cloud resolving to global) to isolate resolution and physics issues from dynamical and model framework issues. Key products will be disseminated to the ARM and larger community through distribution of data archives, including model outputs from the data assimilation products and cloud resolving simulations, and publications.

  10. Home visits by neighborhood Mentor Mothers provide timely recovery from childhoood malnutrition in South Africa: results from a randomized controlled trial

    E-Print Network [OSTI]

    2010-01-01T23:59:59.000Z

    Home visits by neighborhood Mentor Mothers provide timelyHome visits by neighborhood Mentor Mothers provide timelyin a timely manner. Methods: Mentor Mothers were trained to

  11. An Empirical Chart Analysis of the Suitability of Telemedicine for Hospice Visits

    E-Print Network [OSTI]

    Doolittle, Gary C.; Whitten, Pamela; Mccartney, Michael; Cook, David J.; Nazir, Niaman

    2005-03-22T23:59:59.000Z

    Telehospice® (TH) utilizes telemedicine technology to provide care at the end of life. A bistate project was launched in 1998 to study the use of home-based telemedicine for routine hospice care. Videophones were deployed for telenursing visits...

  12. DOE Deputy Secretary and Rosatom Director Visit Y-12, Oak Ridge...

    Energy Savers [EERE]

    DOE Deputy Secretary and Rosatom Director Visit Y-12, Oak Ridge National Laboratory During First Meeting of U.S.-Russian Nuclear Energy and Nuclear Security Working Group DOE...

  13. The Places of Our Lives: Visiting Patterns and Automatic Labeling from Longitudinal

    E-Print Network [OSTI]

    Do,Trinh-Minh-Tri

    to provide location explicitly (via check-ins) or to infer it from sensors [1], [2]. Given the importance affects place visiting patterns. For instance, do woman and men have different patterns? or how

  14. Visite el sitio Web del Instituto de Ciencia Regional, donde encontrar informacin

    E-Print Network [OSTI]

    Snelting, Gregor

    Visite el sitio Web del Instituto de Ciencia Regional, donde encontrará información detallada Instituto de Ciencia Regional Estado de actualización: Junio del 2005 Universität Karlsruhe (TH) Instituto de Ciencia Regional Programa acreditado de Master ,,Ciencia regional/ Planificaión territorial

  15. Sites with Holocene dung deposits in the Eastern Desert of Egypt: Visited by herders?

    E-Print Network [OSTI]

    Marinova, Elena

    Sites with Holocene dung deposits in the Eastern Desert of Egypt: Visited by herders? V. Linseele a by the Belgian Middle Egypt Prehistoric Project of Leuven University under the direction of P.M. Vermeersch

  16. Creating a Parallel Version of VisIt for Microsoft Windows

    SciTech Connect (OSTI)

    Whitlock, B J; Biagas, K S; Rawson, P L

    2011-12-07T23:59:59.000Z

    VisIt is a popular, free interactive parallel visualization and analysis tool for scientific data. Users can quickly generate visualizations from their data, animate them through time, manipulate them, and save the resulting images or movies for presentations. VisIt was designed from the ground up to work on many scales of computers from modest desktops up to massively parallel clusters. VisIt is comprised of a set of cooperating programs. All programs can be run locally or in client/server mode in which some run locally and some run remotely on compute clusters. The VisIt program most able to harness today's computing power is the VisIt compute engine. The compute engine is responsible for reading simulation data from disk, processing it, and sending results or images back to the VisIt viewer program. In a parallel environment, the compute engine runs several processes, coordinating using the Message Passing Interface (MPI) library. Each MPI process reads some subset of the scientific data and filters the data in various ways to create useful visualizations. By using MPI, VisIt has been able to scale well into the thousands of processors on large computers such as dawn and graph at LLNL. The advent of multicore CPU's has made parallelism the 'new' way to achieve increasing performance. With today's computers having at least 2 cores and in many cases up to 8 and beyond, it is more important than ever to deploy parallel software that can use that computing power not only on clusters but also on the desktop. We have created a parallel version of VisIt for Windows that uses Microsoft's MPI implementation (MSMPI) to process data in parallel on the Windows desktop as well as on a Windows HPC cluster running Microsoft Windows Server 2008. Initial desktop parallel support for Windows was deployed in VisIt 2.4.0. Windows HPC cluster support has been completed and will appear in the VisIt 2.5.0 release. We plan to continue supporting parallel VisIt on Windows so our users will be able to take full advantage of their multicore resources.

  17. annual tropical cyclone: Topics by E-print Network

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

    SEASONAL AND MONTHLY FORECASTS Geosciences Websites Summary: 10 12.25 8 5.75 Accumulated Cyclone Energy (ACE) (96.2) 130 170 170 150 148 100 68 Net Tropical't press us too hard on...

  18. WMO/CAS/WWW SIXTH INTERNATIONAL WORKSHOP on TROPICAL CYCLONES

    E-Print Network [OSTI]

    Colorado at Boulder, University of

    to Human and Economic Losses Rapporteur: Roger A. Pielke, Jr. Center for Science and Technology Policy.2.3 Tropical cyclone case studies a) India b) Australia c) United States 5.2.4 Differing views of the role

  19. ambiente tropical um: Topics by E-print Network

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

    Abstract. We show that the tropicalization of an irreducible May 18, 2012. 1089 12;1090 DUSTIN CARTWRIGHT AND SAM PAYNE real closed fields with convex valuation Payne, Sam 460...

  20. Surface Fluxes and Tropical Intraseasonal Variability: a Reassessment

    E-Print Network [OSTI]

    Ribes, Aurélien

    and Department of Earth and Environmental Sciences, Columbia University, New York, New York, USA 2 Department whose essential features -- its existence, energetics, spatial and temporal scales -- remain so be fundamental similarities in their energetics. General circulation models (GCMs) simulate tropical

  1. The Political Economy of Deforestation in the Tropics

    E-Print Network [OSTI]

    Burgess, Robin

    Tropical deforestation accounts for almost one-fifth of greenhouse gas emissions and threatens the world’s most diverse ecosystems. Much of this deforestation is driven by illegal logging. We use novel satellite data that ...

  2. Commercial Building HVAC Energy Usage in Semi-Tropical Climates

    E-Print Network [OSTI]

    Worbs, H. E.

    1987-01-01T23:59:59.000Z

    The design of heating and cooling equipment in semi-tropical climates presents some design considerations and limitations not so prevalent in temperate climates. In some cases, the heating season may be non-existent for all practical purposes...

  3. american tropical cyclone: Topics by E-print Network

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

    24 25 Next Page Last Page Topic Index 21 Cross-equatorial influences of a South American cold surge on the development of two eastern North Pacific tropical cyclones Texas A&M...

  4. The NASA Tropical Composition, Cloud and Climate Coupling Mission

    E-Print Network [OSTI]

    a dramatic effect on the overall amount of radiation and heat the Earth's atmosphere contains. These systems Rica in the Gulf of Panama are remarkably intense for tropical maritime systems due to a number

  5. african tropical forests: Topics by E-print Network

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

    Cory C. Cleveland1,4, and Alan R in tropical rain forests may be among the highest on earth. However, data supporting this contention are rare Cleveland, Cory 116 THE WEST...

  6. african tropical forest: Topics by E-print Network

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

    Cory C. Cleveland1,4, and Alan R in tropical rain forests may be among the highest on earth. However, data supporting this contention are rare Cleveland, Cory 116 THE WEST...

  7. MODELING THE DYNAMICAL COUPLING OF SOLAR CONVECTION WITH THE RADIATIVE INTERIOR

    SciTech Connect (OSTI)

    Brun, Allan Sacha [Laboratoire AIM Paris-Saclay, CEA/Irfu Universite Paris-Diderot CNRS/INSU, 91191 Gif-sur-Yvette (France); Miesch, Mark S. [High Altitude Observatory, NCAR, Boulder, CO 80307-3000 (United States); Toomre, Juri [JILA and Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, CO 80309-0440 (United States)

    2011-12-01T23:59:59.000Z

    The global dynamics of a rotating star like the Sun involves the coupling of a highly turbulent convective envelope overlying a seemingly benign radiative interior. We use the anelastic spherical harmonic code to develop a new class of three-dimensional models that nonlinearly couple the convective envelope to a deep stable radiative interior. The numerical simulation assumes a realistic solar stratification from r = 0.07 up to 0.97R (with R the solar radius), thus encompassing part of the nuclear core up through most of the convection zone. We find that a tachocline naturally establishes itself between the differentially rotating convective envelope and the solid body rotation of the interior, with a slow spreading that is here diffusively controlled. The rapid angular momentum redistribution in the convective envelope leads to a fast equator and slow poles, with a conical differential rotation achieved at mid-latitudes, much as has been deduced by helioseismology. The convective motions are able to overshoot downward about 0.04R into the radiative interior. However, the convective meridional circulation there is confined to a smaller penetration depth and is directed mostly equatorward at the base of the convection zone. Thermal wind balance is established in the lower convection zone and tachocline but departures are evident in the upper convection zone. Internal gravity waves are excited by the convective overshooting, yielding a complex wave field throughout the radiative interior.

  8. Response of tropical sea surface temperature, precipitation, and tropical cyclone-related variables to changes in global and local forcing

    E-Print Network [OSTI]

    Sobel, Adam

    A single-column model is used to estimate the equilibrium response of sea surface temperature (SST), precipitation, and several variables related to tropical cyclone (TC) activity to changes in both local and global forcing. ...

  9. The Tropical Brown Alga Lobophora variegata (Lamouroux) Womersley: A Prospective Bioindicator for Ag Contamination in Tropical Coastal Waters

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    The Tropical Brown Alga Lobophora variegata (Lamouroux) Womersley: A Prospective Bioindicator determined in the brown alga Lobophora variegata, using radiotracer techniques. Results indicate that this widely distributed alga could be a useful bioindicator species for surveying silver contamination

  10. COMPARING THE EFFECT OF RADIATIVE TRANSFER SCHEMES ON CONVECTION SIMULATIONS

    SciTech Connect (OSTI)

    Tanner, Joel D.; Basu, Sarbani; Demarque, Pierre [Astronomy Department, Yale University, P.O. Box 208101, New Haven, CT 06520-8101 (United States)

    2012-11-10T23:59:59.000Z

    We examine the effect of different radiative transfer schemes on the properties of three-dimensional (3D) simulations of near-surface stellar convection in the superadiabatic layer, where energy transport transitions from fully convective to fully radiative. We employ two radiative transfer schemes that fundamentally differ in the way they cover the 3D domain. The first solver approximates domain coverage with moments, while the second solver samples the 3D domain with ray integrations. By comparing simulations that differ only in their respective radiative transfer methods, we are able to isolate the effect that radiative efficiency has on the structure of the superadiabatic layer. We find the simulations to be in good general agreement, but they show distinct differences in the thermal structure in the superadiabatic layer and atmosphere.

  11. Midlatitude Continental Convective Clouds Experiment (MC3E)

    SciTech Connect (OSTI)

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

    2010-04-10T23:59:59.000Z

    The Midlatitude Continental Convective Clouds Experiment (MC3E) will take place in central Oklahoma during the April–May 2011 period. The experiment is a collaborative effort between the U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Climate Research Facility and the National Aeronautics and Space Administration’s (NASA) Global Precipitation Measurement (GPM) mission Ground Validation (GV) program. The field campaign leverages the unprecedented observing infrastructure currently available in the central United States, combined with an extensive sounding array, remote sensing and in situ aircraft observations, NASA GPM ground validation remote sensors, and new ARM instrumentation purchased with American Recovery and Reinvestment Act funding. The overarching goal is to provide the most complete characterization of convective cloud systems, precipitation, and the environment that has ever been obtained, providing constraints for model cumulus parameterizations and space-based rainfall retrieval algorithms over land that have never before been available.

  12. Convection in multiphase flows using Lattice Boltzmann methods

    E-Print Network [OSTI]

    L. Biferale; P. Perlekar; M. Sbragaglia; F. Toschi

    2011-11-03T23:59:59.000Z

    We present high resolution numerical simulations of convection in multiphase flows (boiling) using a novel algorithm based on a Lattice Boltzmann method. We first validate the thermodynamical and kinematical properties of the algorithm. Then, we perform a series of 3d numerical simulations at changing the mean properties in the phase diagram and compare convection with and without phase coexistence at $Ra \\sim 10^7$. We show that in presence of nucleating bubbles non-Oberbeck Boussinesq effects develops, mean temperature profile becomes asymmetric, heat-transfer and heat-transfer fluctuations are enhanced. We also show that small-scale properties of velocity and temperature fields are strongly affected by the presence of buoyant bubble leading to high non-Gaussian profiles in the bulk.

  13. Dissipation Efficiency in Turbulent Convective Zones in Low Mass Stars

    E-Print Network [OSTI]

    Kaloyan Penev; Dimitar Sasselov; Frank Robinson; Pierre Demarque

    2009-09-26T23:59:59.000Z

    We extend the analysis of Penev et al. (2007) to calculate effective viscosities for the surface convective zones of three main sequence stars of 0.775Msun, 0.85Msun and the present day Sun. In addition we also pay careful attention to all normalization factors and assumptions in order to derive actual numerical prescriptions for the effective viscosity as a function of the period and direction of the external shear. Our results are applicable for periods that are too long to correspond to eddies that fall within the inertial subrange of Kolmogorov scaling, but no larger than the convective turnover time, when the assumptions of the calculation break down. We find linear scaling of effective viscosity with period and magnitudes at least three times larger than the Zahn (1966, 1989) prescription.

  14. The Critical Rayleigh Number in Horizontal Convection for $\\Pran=1$

    E-Print Network [OSTI]

    Sun, L; Sun, De-Jun; Sun, Liang

    2007-01-01T23:59:59.000Z

    We report the numerical simulations of the horizontal convection within a rectangle cavity tank at high Rayleigh numbers. The physical solution of horizontal convection depends the space resolution of the meshes. The mesh number $N$ is proportion to $Ra^{1/3}$. The unstable numerical solutions are obtained as $Npower law also implies that the space resolution is dominated by the viscosity and heat diffusion. It implies that the special resolution is dominated by viscosity and thermal diffusivity but the length of the tank. Moreover, there is a Hopf bifurcation from steady solutions to unsteady solutions and the critical Rayleigh number $Ra_c$ is obtained as $5.53\\times 10^8

  15. Diamagnetic pumping near the base of a stellar convection zone

    E-Print Network [OSTI]

    L. L. Kitchatinov; G. Rüdiger

    2008-02-18T23:59:59.000Z

    The property of inhomogeneous turbulence in conducting fluids to expel large-scale magnetic fields in the direction of decreasing turbulence intensity is shown as important for the magnetic field dynamics near the base of a stellar convection zone. The downward diamagnetic pumping confines a fossil internal magnetic field in the radiative core so that the field geometry is appropriate for formation of the solar tachocline. For the stars of solar age, the diamagnetic confinement is efficient only if the ratio of turbulent magnetic diffusivity of the convection zone to the (microscopic or turbulent) diffusivity of the radiative interiour is larger than 10^5. Confinement in younger stars require still larger diffusivity ratio. The observation of persistent magnetic structures on young solar-type stars can thus provide evidences for the nonexistence of tachoclines in stellar interiors and on the level of turbulence in radiative cores.

  16. 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.

  17. Influence of geometry on natural convection in buildings

    SciTech Connect (OSTI)

    White, M.D.; Winn, C.B.; Jones, G.F.; Balcomb, J.D.

    1985-01-01T23:59:59.000Z

    Strong free convection airflows occur within passive solar buildings resulting from elevated temperatures of surfaces irradiated by solar energy compared with the cooler surfaces not receiving radiation. The geometry of a building has a large influence on the directions and magnitudes of natural airflows, and thus heat transfer between zones. This investigation has utilized a variety of reduced-scale building configurations to study the effects of geometry on natural convection heat transfer. Similarity between the reduced-scale model and a full-scale passive solar building is achieved by having similar geometries and by replacing air with Freon-12 gas as the model's working fluid. Filling the model with Freon-12 gas results in similarity in Prandtl numbers and Rayleigh numbers based on temperature differences in the range from 10/sup 9/ to 10/sup 11/. Results from four geometries are described with an emphasis placed on the effects of heat loss on zone temperature stratification shifts.

  18. THE DOMINANCE OF NEUTRINO-DRIVEN CONVECTION IN CORE-COLLAPSE SUPERNOVAE

    SciTech Connect (OSTI)

    Murphy, Jeremiah W.; Dolence, Joshua C.; Burrows, Adam, E-mail: jmurphy@astro.princeton.edu, E-mail: jdolence@astro.princeton.edu, E-mail: burrows@astro.princeton.edu [Princeton University, Princeton, NJ (United States)

    2013-07-01T23:59:59.000Z

    Multi-dimensional instabilities have become an important ingredient in core-collapse supernova (CCSN) theory. Therefore, it is necessary to understand the driving mechanism of the dominant instability. We compare our parameterized three-dimensional CCSN simulations with other buoyancy-driven simulations and propose scaling relations for neutrino-driven convection. Through these comparisons, we infer that buoyancy-driven convection dominates post-shock turbulence in our simulations. In support of this inference, we present four major results. First, the convective fluxes and kinetic energies in the neutrino-heated region are consistent with expectations of buoyancy-driven convection. Second, the convective flux is positive where buoyancy actively drives convection, and the radial and tangential components of the kinetic energy are in rough equipartition (i.e., K{sub r} {approx} K{sub {theta}} + K{sub {phi}}). Both results are natural consequences of buoyancy-driven convection, and are commonly observed in simulations of convection. Third, buoyant driving is balanced by turbulent dissipation. Fourth, the convective luminosity and turbulent dissipation scale with the driving neutrino power. In all, these four results suggest that in neutrino-driven explosions, the multi-dimensional motions are consistent with neutrino-driven convection.

  19. 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...

  20. AERIAL MEASUREMENTS OF CONVECTION CELL ELEMENTS IN HEATED LAKES

    SciTech Connect (OSTI)

    Villa-Aleman, E; Saleem Salaymeh, S; Timothy Brown, T; Alfred Garrett, A; Malcolm Pendergast, M; Linda Nichols, L

    2007-12-19T23:59:59.000Z

    Power plant-heated lakes are characterized by a temperature gradient in the thermal plume originating at the discharge of the power plant and terminating at the water intake. The maximum water temperature discharged by the power plant into the lake depends on the power generated at the facility and environmental regulations on the temperature of the lake. Besides the observed thermal plume, cloud-like thermal cells (convection cell elements) are also observed on the water surface. The size, shape and temperature of the convection cell elements depends on several parameters such as the lake water temperature, wind speed, surfactants and the depth of the thermocline. The Savannah River National Laboratory (SRNL) and Clemson University are collaborating to determine the applicability of laboratory empirical correlations between surface heat flux and thermal convection intensity. Laboratory experiments at Clemson University have demonstrated a simple relationship between the surface heat flux and the standard deviation of temperature fluctuations. Similar results were observed in the aerial thermal imagery SRNL collected at different locations along the thermal plume and at different elevations. SRNL will present evidence that the results at Clemson University are applicable to cooling lakes.

  1. SOUND-SPEED INVERSION OF THE SUN USING A NONLOCAL STATISTICAL CONVECTION THEORY

    SciTech Connect (OSTI)

    Zhang Chunguang; Deng Licai [Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China); Xiong Darun [Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008 (China); Christensen-Dalsgaard, Jorgen, E-mail: cgzhang@nao.cas.cn [Stellar Astrophysics Centre, Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C (Denmark)

    2012-11-01T23:59:59.000Z

    Helioseismic inversions reveal a major discrepancy in sound speed between the Sun and the standard solar model just below the base of the solar convection zone. We demonstrate that this discrepancy is caused by the inherent shortcomings of the local mixing-length theory adopted in the standard solar model. Using a self-consistent nonlocal convection theory, we construct an envelope model of the Sun for sound-speed inversion. Our solar model has a very smooth transition from the convective envelope to the radiative interior, and the convective energy flux changes sign crossing the boundaries of the convection zone. It shows evident improvement over the standard solar model, with a significant reduction in the discrepancy in sound speed between the Sun and local convection models.

  2. Tropical climate variability from the last glacial maximum to the present

    E-Print Network [OSTI]

    Dahl, Kristina Ariel

    2005-01-01T23:59:59.000Z

    This thesis evaluates the nature and magnitude of tropical climate variability from the Last Glacial Maximum to the present. The temporal variability of two specific tropical climate phenomena is examined. The first is the ...

  3. Vertical flux, ecology and dissolution of radiolaria in tropical oceans : implications for the silica cycle

    E-Print Network [OSTI]

    Takahashi, Kozo

    1982-01-01T23:59:59.000Z

    Radiolarians which settle through the oceanic water column were recovered from three stations (western Tropical Atlantic-Station E, central Tropical Pacific-P1 and Panama Basin-PB) using PARFLUX sediment traps in moored ...

  4. The Role of Mineralogy in Organic Matter Stabilization in Tropical Soils

    E-Print Network [OSTI]

    Sparks, Donald L.

    The Role of Mineralogy in Organic Matter Stabilization in Tropical Soils Wipawan Thaymuang,1 Irb) and mineralogy. This study investigated the mineral properties and OM stabilization in 12 surface tropical soil

  5. Sensitivity of Tropical Cyclone Intensity to Ventilation in an Axisymmetric Model

    E-Print Network [OSTI]

    Tang, Brian

    The sensitivity of tropical cyclone intensity to ventilation of cooler, drier air into the inner core is examined using an axisymmetric tropical cyclone model with parameterized ventilation. Sufficiently strong ventilation ...

  6. Geographic variation in vulnerability to climate warming in a tropical Caribbean lizard

    E-Print Network [OSTI]

    Leal, Manuel S.

    Geographic variation in vulnerability to climate warming in a tropical Caribbean lizard Alex R temperatures (Tb) of the tropical Caribbean lizard Anolis cristatellus at nine sites representing two habitat

  7. LONDON SCHOOL OF HYGIENE & TROPICAL MEDICINE FREEDOM OF INFORMATION ACT 2000

    E-Print Network [OSTI]

    Maizels, Rick

    1 LONDON SCHOOL OF HYGIENE & TROPICAL MEDICINE FREEDOM OF INFORMATION ACT 2000 REQUEST help. NB. The London School of Hygiene & Tropical Medicine has the right to ask for clarification

  8. London School of Hygiene & Tropical The School is a world-leading centre for

    E-Print Network [OSTI]

    Maizels, Rick

    London School of Hygiene & Tropical Medicine The School is a world-leading centre for research information Registry London School of Hygiene & Tropical Medicine Keppel Street London WC1E 7HT UNITED KINGDOM

  9. How might a statistical cloud scheme be coupled to a mass-flux convection scheme?

    SciTech Connect (OSTI)

    Klein, Stephen A.; Pincus, Robert; Hannay, Cecile; Xu, Kuan-man

    2004-09-27T23:59:59.000Z

    The coupling of statistical cloud schemes with mass-flux convection schemes is addressed. Source terms representing the impact of convection are derived within the framework of prognostic equations for the width and asymmetry of the probability distribution function of total water mixing ratio. The accuracy of these source terms is quantified by examining output from a cloud resolving model simulation of deep convection. Practical suggestions for inclusion of these source terms in large-scale models are offered.

  10. Tropical forest responses to increasing atmospheric CO2: current knowledge and opportunities for future research

    E-Print Network [OSTI]

    Bermingham, Eldredge

    their representation in Earth system models. Tropical forests play a significant role in the global carbon cycle

  11. Tropical Forestry Researchat the USDA Forest Service's Instituteof Pacific Islands Forestry1

    E-Print Network [OSTI]

    Standiford, Richard B.

    Tropical Forestry Researchat the USDA Forest Service's Instituteof Pacific Islands Forestry1 C greater emphasis on tropical forestry management and research was provided by the International Forestry Islands Forestry in Hawaii, the Institute of Tropical Forestry in Puerto Rico, and the U S . Forest

  12. Developing versus Nondeveloping Disturbances for Tropical Cyclone Formation. Part I: North Atlantic*

    E-Print Network [OSTI]

    Li, Tim

    Developing versus Nondeveloping Disturbances for Tropical Cyclone Formation. Part I: North Atlantic the characteristic differences of tropical disturbances that eventually develop into tropical cyclones (TCs) versus for TC genesis in the North Atlantic. When the east and west (separated by 408W) Atlantic are examined

  13. Notes and Correspondence Are Tropical Cyclones Less Effectively Formed by Easterly Waves in the

    E-Print Network [OSTI]

    Chen, Tsing-Chang "Mike"

    tropical cyclones in the western North Pacific. By carefully separating easterly waves from the lowerNotes and Correspondence Are Tropical Cyclones Less Effectively Formed by Easterly Waves@iastate.edu #12;1 Abstract It has been observed that the percentage of tropical cyclones originating from easterly

  14. Midlevel Ventilation's Constraint on Tropical Cyclone Intensity BRIAN TANG AND KERRY EMANUEL

    E-Print Network [OSTI]

    Emanuel, Kerry A.

    Midlevel Ventilation's Constraint on Tropical Cyclone Intensity BRIAN TANG AND KERRY EMANUEL ventilation, or the flux of low-entropy air into the inner core of a tropical cyclone (TC), is a hy to assess how ventilation affects tropical cyclone intensity via two possible pathways: the first through

  15. Regional Patterns of Tropical Indo-Pacific Climate Change: Evidence of the Walker Circulation Weakening*

    E-Print Network [OSTI]

    Xie, Shang-Ping

    in the tropical eastern Pacific and western Indian Ocean than in the tropical western Pacific and eastern IndianRegional Patterns of Tropical Indo-Pacific Climate Change: Evidence of the Walker Circulation Weakening* HIROKI TOKINAGA, SHANG-PING XIE, AND AXEL TIMMERMANN International Pacific Research Center, SOEST

  16. An optimizing reduced order FDS for the tropical Pacific Ocean reduced gravity model

    E-Print Network [OSTI]

    Aluffi, Paolo

    An optimizing reduced order FDS for the tropical Pacific Ocean reduced gravity model Zhendong Luoa) for the tropical Pacific Ocean reduced gravity model. Ensembles of data are compiled from transient solutions computed from the discrete equation system derived by FDS for the tropical Pacific Ocean reduced gravity

  17. Primary production in the eastern tropical Pacific: A review J. Timothy Pennington a

    E-Print Network [OSTI]

    Pennington, J. Timothy

    , Peru Abstract The eastern tropical Pacific includes 28 million km2 of ocean between 23.5°N phytoplankton growth (and nitrogen fixation) over large portions of the open-ocean eastern tropical Pacific Pacific. Seasonal cycles are weak over much of the open-ocean eastern tropical Pacific, although several

  18. Reduced Order Modeling of the Upper Tropical Pacific Ocean Model Using Proper Orthogonal Decomposition

    E-Print Network [OSTI]

    Aluffi, Paolo

    Reduced Order Modeling of the Upper Tropical Pacific Ocean Model Using Proper Orthogonal of a large-scale upper ocean circulation in the tropic Pacific domain. We construct different POD models-scale seasonal variability of the tropic Pacific obtained by the original model is well captured by a low

  19. Eddy mean flow decomposition and eddy diffusivity estimates in the tropical Pacific Ocean

    E-Print Network [OSTI]

    Eddy mean flow decomposition and eddy diffusivity estimates in the tropical Pacific Ocean: 2] Eddy diffusivity of the surface velocity field in the tropical Pacific Ocean was estimated using diffusivity estimates in the tropical Pacific Ocean: 2. Results, J. Geophys. Res., 107(C10), 3154, doi:10

  20. Interhemispheric Teleconnections from Tropical Heat Sources in Intermediate and Simple Models

    E-Print Network [OSTI]

    the prescribed tropical heating in both intensity and geographical extent and by inducing remote precipitation anomalies by interaction with the basic state. 1. Introduction Tropical heat sources can remotely influenceInterhemispheric Teleconnections from Tropical Heat Sources in Intermediate and Simple Models XUAN

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

    E-Print Network [OSTI]

    Wang, Chunzai

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

  2. Regional feedbacks among fire, climate, and tropical deforestation William A. Hoffmann1

    E-Print Network [OSTI]

    Jackson, Robert B.

    Regional feedbacks among fire, climate, and tropical deforestation William A. Hoffmann1 December 2003. [1] Numerous studies with general circulation models suggest that tropical deforestation can to estimate the effect of tropical deforestation on fire risk through the McArthur forest fire danger index

  3. Global warming shifts Pacific tropical cyclone location MinHo Kwon,1,3

    E-Print Network [OSTI]

    Li, Tim

    Global warming shifts Pacific tropical cyclone location Tim Li,1 MinHo Kwon,1,3 Ming Zhao,3 Jong) is used to investigate the change of tropical cyclone frequency in the North Pacific under global warming, and W. Yu (2010), Global warming shifts Pacific tropical cyclone location, Geophys. Res. Lett., 37, L

  4. Interactions between the tropical ISO and midlatitude low-frequency flow

    E-Print Network [OSTI]

    Li, Tim

    Interactions between the tropical ISO and midlatitude low-frequency flow Lin-Lin Pan Æ Tim Li Abstract In this study, we investigate the interaction between the tropical Intraseasonal Oscillation (ISO study the role of the syn- optic eddy feedback in the midlatitude response to the tropical ISO forcing

  5. Natural convection in high heat flux tanks at the Hanford Waste Site / [by] Mark van der Helm and Mujid S. Kazimi

    E-Print Network [OSTI]

    Van der Helm, Mark Johan, 1972-

    1996-01-01T23:59:59.000Z

    A study was carried out on the potential for natural convection and the effect of natural convection in a High Heat Flux Tank, Tank 241-C-106, at the Hanford Reservation. To determine the existence of natural convection, ...

  6. Water Vapor Turbulence Profiles in Stationary Continental Convective Mixed Layers

    SciTech Connect (OSTI)

    Turner, D. D.; Wulfmeyer, Volker; Berg, Larry K.; Schween, Jan

    2014-10-08T23:59:59.000Z

    The U.S. Department of Energy Atmospheric Radiation Measurement (ARM) program’s Raman lidar at the ARM Southern Great Plains (SGP) site in north-central Oklahoma has collected water vapor mixing ratio (q) profile data more than 90% of the time since October 2004. Three hundred (300) cases were identified where the convective boundary layer was quasi-stationary and well-mixed for a 2-hour period, and q mean, variance, third order moment, and skewness profiles were derived from the 10-s, 75-m resolution data. These cases span the entire calendar year, and demonstrate that the q variance profiles at the mixed layer (ML) top changes seasonally, but is more related to the gradient of q across the interfacial layer. The q variance at the top of the ML shows only weak correlations (r < 0.3) with sensible heat flux, Deardorff convective velocity scale, and turbulence kinetic energy measured at the surface. The median q skewness profile is most negative at 0.85 zi, zero at approximately zi, and positive above zi, where zi is the depth of the convective ML. The spread in the q skewness profiles is smallest between 0.95 zi and zi. The q skewness at altitudes between 0.6 zi and 1.2 zi is correlated with the magnitude of the q variance at zi, with increasingly negative values of skewness observed lower down in the ML as the variance at zi increases, suggesting that in cases with larger variance at zi there is deeper penetration of the warm, dry free tropospheric air into the ML.

  7. Convection induced by radiative cooling of a layer of participating medium

    SciTech Connect (OSTI)

    Prasanna, Swaminathan, E-mail: prasannaswam@gmail.com [Laboratoire EM2C, CNRS UPR 288 92295, Chatenay-Malabry, France and Ecole Centrale Paris, Grande Voie des Vignes 92295, Chatenay-Malabry (France)] [Laboratoire EM2C, CNRS UPR 288 92295, Chatenay-Malabry, France and Ecole Centrale Paris, Grande Voie des Vignes 92295, Chatenay-Malabry (France); Venkateshan, S. P., E-mail: spv@iitm.ac.in [HTTP Laboratory, Department of Mechanical Engineering IIT Madras, Chennai (India)

    2014-05-15T23:59:59.000Z

    Simulations and experiments have been conducted to study the effect of radiative cooling on natural convection in a horizontal layer of a participating medium enclosed between isothermal opaque wall and radiatively transparent wall and exposed to a cold background. The study is of relevance to a nocturnal boundary layer under clear and calm conditions. The focus of the study is to capture the onset of convection caused by radiative cooling. The experiments have been designed to mimic the atmospheric radiative boundary conditions, and hence decoupling convection and radiation boundary conditions. Planck number Pl and optical thickness of the layer ?{sub H} are the two important parameters that govern the interaction between radiation and convection. The radiation-convection coupling is a strong function of length scale. Convection sets up within first few seconds for all the experiments. Strong plume like convection is observed for the experimental conditions used in the present study. Both simulations and experiments confirm that radiative cooling increases substantially with decrease in emissivity of the bottom wall. Radiative cooling is strongly influenced by the nongray nature of the participating medium, especially when strong emission from the medium escapes to space, in the window region of the atmosphere. Accurate representation of radiative properties is critical. Linear stability analysis of onset of convection indicates that radiation stabilizes convection as Pl decreases. The observations are similar to the case of Rayleigh Bénard convection in a radiating gas. However, for both experimental and numerical conditions, the observed Rayleigh numbers are much greater than the critical Rayleigh number. To conclude, the role of radiation is to drive and sustain convection in the unstable layer.

  8. Generation of large-scale winds in horizontally anisotropic convection

    E-Print Network [OSTI]

    von Hardenberg, J; Provenzale, A; Spiegel, E A

    2015-01-01T23:59:59.000Z

    We simulate three-dimensional, horizontally periodic Rayleigh-B\\'enard convection between free-slip horizontal plates, rotating about a horizontal axis. When both the temperature difference between the plates and the rotation rate are sufficiently large, a strong horizontal wind is generated that is perpendicular to both the rotation vector and the gravity vector. The wind is turbulent, large-scale, and vertically sheared. Horizontal anisotropy, engendered here by rotation, appears necessary for such wind generation. Most of the kinetic energy of the flow resides in the wind, and the vertical turbulent heat flux is much lower on average than when there is no wind.

  9. Redistribution of trace chemical species by a small convective cloud

    SciTech Connect (OSTI)

    Stith, J.L.; Alkezweeny, A.J.; Pleim, J.E.; Ching, J.K.S.

    1993-01-01T23:59:59.000Z

    The paper describes a new experiment with a SF6 tracer to determine the mixing history of a small region of cloud-base air. In situ measurements of the SF6 are made to follow the region and simultaneous measurements of natural trace gases are used to determine the dilution of the tagged region as it is affected by the cloud. After describing the experimental method, the results from an experiment with a small cumulus, which was ideally suited for the experiment, are explained. The goal of the paper is to better understand how convective clouds redistribute trace constituents (e.g. moisture, trace gases) in the vertical.

  10. SRS reactor control rod cooling without normal forced convection cooling

    SciTech Connect (OSTI)

    Smith, D.C. (SAIC, Albuquerque, NM (United States)); Easterling, T.C. (Westinghouse Savannah River Co., Aiken, SC (United States))

    1993-01-01T23:59:59.000Z

    This paper describes an analytical study of the coolability of the control rods in the Savannah River site (SRS) K production reactor under conditions of loss of normal forced convection cooling. The study was performed as part of the overall safety analysis of the reactor supporting its restart. The analysis addresses the buoyancy-driven boiling flow over the control rods that occurs when forced cooling is lost. The objective of the study was to demonstrate that the control rods will remain cooled (i.e., no melting) at powers representative of those anticipated for restart of the reactor.

  11. A numerical study of convection with an ambient wind field

    E-Print Network [OSTI]

    Cottrell, Kit Garfield

    1970-01-01T23:59:59.000Z

    equations in ehe same order as in (8. 16)-(8. 19). ? TEB = TEB1 + TEB2 at ? TEC = TEC1 + TEC2 a at ? NEB = MEB1 + NEB2 a ae ? NEC = MEC1 + NEC2 + MEC3 + HECT a at TEB and TEC are the thermal energies for the basic and con- vective flows, respectively...; likewise, MZB and MEC are the mechanical energies for the basic and convective flows. The evaluation of ehese terms at each time step represents the total amount of energy presene in these forms. TEB1 represents a thermal energy transformation...

  12. Gradients of meteorological parameters in convective and nonconvective areas

    E-Print Network [OSTI]

    McCown, Milton Samuel

    1976-01-01T23:59:59.000Z

    . SYNOPTIC CONDITIONS 4. STRATIFICATION OF DATA 5. COMPUTATIONAL PROCEDURES 21 25 a. Gridding of rawinsonde data 25 b. Gradients 26 5'' lp t* 27 RESULTS 29 a. Gradients 29 1) Convective areas 29 2) Nonconvective areas 31 3) Combined areas 33 vi... air turbulence. By using airplane data from over the western United States, Scoggins (1975) has shown that CAT at 300 mb occurred 71% of the time when the magnitude of the vector horizontal wind shear -5 -1 exceeded 4. 5 x 10 sec . The horizontal...

  13. Convection feedbacks in a super-parameterization GCM

    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

  14. Acute poisoning is a common reason for visits to emergency departments and for hospitalization

    E-Print Network [OSTI]

    Bushman, Frederic

    ACUTE POISONING jUNE 2012, Issue 6 Acute poisoning is a common reason for visits to emergency departments and for hospitalization worldwide. The prevalence of acute poisoning in Southern Africa varies between 1 and 17%1 and available evidence from Botswana suggests that acute poisoning ranks third among

  15. HOUSING GUIDE FOR VISITING RESEARCHERS Keys to better understanding French rental rules

    E-Print Network [OSTI]

    Jeanjean, Louis

    HOUSING GUIDE FOR VISITING RESEARCHERS Keys to better understanding French rental rules Document written by the Housing Working Group of the association EURAXESS FRANCE #12;Housing guide Euraxess France................................................................................................................P.3 o Key Principles of House Renting in France...........................................P.4 o

  16. Re-visiting the Foundations of Artificial Immune Systems for Data Mining

    E-Print Network [OSTI]

    Timmis, Jon

    Re-visiting the Foundations of Artificial Immune Systems for Data Mining Alex A. Freitas Jon Timmis) for data mining. By problem-oriented approach we mean that, in real-world data mining applications, the design of an AIS should take into account the characteristics of the data to be mined together

  17. Appendix B: Site Visit Reports. Assessment of Research Needs for Coal Utilization

    SciTech Connect (OSTI)

    Penner, S.S.

    1983-05-01T23:59:59.000Z

    This section contains edited copies of site-visit and other reports prepared by CCAWG members. Some of the hand-out materials prepared by DOE contractors and others are included (without explication) to permit readers the construction of a coherent picture of work in progress.

  18. Welcome to San Francisco State University. Questions about this tour? Visit Student

    E-Print Network [OSTI]

    Cox Stadium. 6. Thornton Hall This is home to the College of Science and Engineering and its departments of Physics and Astronomy, Chemistry and Biochemistry, Computer Science, GeosciencesWelcome to San Francisco State University. Questions about this tour? Visit Student Outreach

  19. ADVANCE Program Site Visit Report The University of Wisconsin at Madison

    E-Print Network [OSTI]

    Sheridan, Jennifer

    - 1 - 1/25/2006 ADVANCE Program Site Visit Report The University of Wisconsin at Madison November 7 institutional change at a major research university with few women faculty in the science and engineering in the College of Engineering, Agricultural and Life Sciences, Letters and Sciences, Schools of Medicine

  20. Map of wireless networks For more information on University wireless services visit

    E-Print Network [OSTI]

    Martin, Stephen John

    Map of wireless networks For more information on University wireless services visit: http://www.shef.ac.uk/cics/wireless. Corporate Information and Computing Services. Connecting To the Wireless Network. Mac OS X, Apple iPhone and iPod Touch #12;Connecting to the eduroam wireless network Mac OS X Prerequisites Mac OS X 10

  1. USFS Administrative Tour The Aspen FACE site hosted a visit of some 36 senior

    E-Print Network [OSTI]

    1 USFS Administrative Tour The Aspen FACE site hosted a visit of some 36 senior USFS administrators (USFS) welcomed the group to the site and Dave Karnosky (MTU) gave a brief overview of the Aspen FACE Global Change Program Director Rich Birdsey. Aspen FACE in the News On May 16, 2003, the Aspen FACE

  2. INTERIOR LIGHTING CASE STUDY For more information, visit PARTNERSHIPDEMONSTRATIONS.ORG

    E-Print Network [OSTI]

    California at Davis, University of

    INTERIOR LIGHTING CASE STUDY » For more information, visit PARTNERSHIPDEMONSTRATIONS.ORG In 2013 the SPEED team collaborated with UC San Francisco to demonstrate three lighting retrofits of fluorescent the feasibility of adaptive corridor lighting retrofits for sites with different budgets and financing

  3. EXTERIOR LIGHTING CASE STUDY For more information, visit PARTNERSHIPDEMONSTRATIONS.ORG

    E-Print Network [OSTI]

    California at Davis, University of

    EXTERIOR LIGHTING CASE STUDY » For more information, visit PARTNERSHIPDEMONSTRATIONS.ORG In 2013, UC Santa Barbara partnered with the SPEED team to demonstrate network controlled LED lighting sensors. These lighting controls allowed all the units to be incorporated into an adaptive mesh network

  4. Institute for Health Research and Policy Distinguished Lecture Pfizer Visiting Professorship of Clear Health Communication

    E-Print Network [OSTI]

    Illinois at Chicago, University of

    Institute for Health Research and Policy Distinguished Lecture Pfizer Visiting Professorship of Clear Health Communication April 8, 2009 Matthew W. Kreuter, PhD, MPH Washington University in St. Louis St. Louis, MO Communication-based strategies to eliminate health disparities in diverse populations

  5. Closing Remarks: A Visit to Dr. Stout's and Dr. Murphy's Forest Health Clinic

    E-Print Network [OSTI]

    Fried, Jeremy S.

    Closing Remarks: A Visit to Dr. Stout's and Dr. Murphy's Forest Health Clinic RussellT. Graham and the partici- silvicultu-ristsin central North Carolina. Camp pants. Terrie and I were looking for a clinic is complete, I might attend a rehabilitation clinic. She said a clinic would help me readjust to society

  6. Visit in Iran from August 23 to September 6, 2003 Michel Waldschmidt

    E-Print Network [OSTI]

    Waldschmidt, Michel

    Visit in Iran from August 23 to September 6, 2003 by Michel Waldschmidt Introduction. In August of Mathematicians). There I met the representatives of Iran, Dr Mehdi Behzad, President of the Iranian Mathematical to Iran to go there. She helped me to contact the Director of this institute, Professor Youssef Sobuti

  7. Waste Incineration in China page 1 Figure 1: Visit to MWI in Harbin

    E-Print Network [OSTI]

    Columbia University

    Waste Incineration in China page 1 Figure 1: Visit to MWI in Harbin Waste Incineration in China Balz Solenthaler, Rainer Bunge Summary China currently operates 19 municipal waste incinerators (MWI of the low calorific value of the waste (approx. 5 MJ/kg), incineration on a fluidized bed and the addition

  8. Grant Title: ADVANCING HOME VISITING RESEARCH TO INFORM PUBLIC POLICY Funding Opportunity Number: N/A

    E-Print Network [OSTI]

    Farritor, Shane

    Center on the States, promotes smart state investments in quality, home-based programs for newGrant Title: ADVANCING HOME VISITING RESEARCH TO INFORM PUBLIC POLICY Funding Opportunity Number: N Charitable Trusts. Area of Research: Home-based programs for new and expectant families. Release

  9. Possible linkages between Saharan dust and tropical cyclone rain band invigoration in the eastern Atlantic during NAMMA-06

    E-Print Network [OSTI]

    Rutledge, Steven

    for tropical cyclogenesis, it also provides an infusion of cloud condensation and ice nuclei which can

  10. Temporal Changes in a Tropical Nekton Assemblage and

    E-Print Network [OSTI]

    Temporal Changes in a Tropical Nekton Assemblage and Performance of a Prawn Selective Gear TING and weights of 39 trials conductedfor a selective prawning gear whose performance in bycatch reduc tionI., 1975; Rob erts, 1978; Allen and Coates, 1990), but is extremely rich in the marine coun terpart

  11. Environmental Factors Affecting Tropical Cyclone Power Dissipation KERRY EMANUEL

    E-Print Network [OSTI]

    Emanuel, Kerry A.

    - son 1974; Webster et al. 2005), and the Accumulated Cyclone Energy (ACE) index (Bell et al. 2000, the PDI is also accumulated over each year. Annually accumulated integral metrics such as ACE and PDI showEnvironmental Factors Affecting Tropical Cyclone Power Dissipation KERRY EMANUEL Program

  12. Low beta diversity of herbivorous insects in tropical forests

    E-Print Network [OSTI]

    Basset, Yves

    LETTERS Low beta diversity of herbivorous insects in tropical forests Vojtech Novotny1 , Scott E) and fruit (fruitflies, Diptera) found a low rate of change in species composition (beta diversity) across 75 of kilo- metres. Low beta diversity was also documented in groups with differing host specificity

  13. Variable Responses of Lowland Tropical Forest Nutrient Status

    E-Print Network [OSTI]

    Harms, Kyle E.

    Variable Responses of Lowland Tropical Forest Nutrient Status to to play a key role in nutrient retention. We discuss our findings in the context of possible impacts Springer Science+Business Media, LLC 387 #12;growth not only alters forests' nutrient demands but also

  14. Detection of iodine monoxide in the tropical free troposphere

    E-Print Network [OSTI]

    19, 2012) Atmospheric iodine monoxide (IO) is a radical that catalytically destroys heat trapping in the remote tropical marine boundary layer (MBL) (2­4). IO further affects the oxidative capacity iodine species over the remote ocean remain poorly understood (11, 14) but are currently thought

  15. TROPICAL MULTIPLICATION MAPS AND THE GIESEKER-PETRI THEOREM

    E-Print Network [OSTI]

    Payne, Sam

    TROPICAL MULTIPLICATION MAPS AND THE GIESEKER-PETRI THEOREM DAVID JENSEN AND SAM PAYNE Abstract. We. Supported in part by NSF grants DMS­1068689 and CAREER DMS­1149054. 1 #12;2 DAVID JENSEN AND SAM PAYNE v1 w1 by the addition or deletion of a bridge are canonically isomorphic, and these isomorphisms respect the images of the

  16. Fungal endophytes limit pathogen damage in a tropical tree

    E-Print Network [OSTI]

    Bermingham, Eldredge

    Fungal endophytes limit pathogen damage in a tropical tree A. Elizabeth Arnold* , Luis Carlos Meji species examined to date harbors endophytic fungi within its asymptomatic aerial tissues, such that endophytes rep- resent a ubiquitous, yet cryptic, component of terrestrial plant communities. Fungal

  17. Global Patterns of Ecological Productivity and Tropical Forest Biomass

    E-Print Network [OSTI]

    Wisconsin at Madison, University of

    those measurements in addition to climate data to construct a suite of empirical models of NPP productivity (NPP) on a global scale and biomass accumulation across thee tropics. Scientists have been model of terrestrial net primary productivity (NPP), and its simplicity and relative accuracy has led

  18. Tropical forest soil microbial communities couple iron and carbon biogeochemistry

    SciTech Connect (OSTI)

    Dubinsky, E.A.; Silver, W.L.; Firestone, M.K.

    2009-10-15T23:59:59.000Z

    We report that iron-reducing bacteria are primary mediators of anaerobic carbon oxidation in upland tropical soils spanning a rainfall gradient (3500 - 5000 mm yr-1) in northeast Puerto Rico. The abundant rainfall and high net primary productivity of these tropical forests provide optimal soil habitat for iron-reducing and iron-oxidizing bacteria. Spatially and temporally dynamic redox conditions make iron-transforming microbial communities central to the belowground carbon cycle in these wet tropical forests. The exceedingly high abundance of iron-reducing bacteria (up to 1.2 x 10{sup 9} cells per gram soil) indicated that they possess extensive metabolic capacity to catalyze the reduction of iron minerals. In soils from the higher rainfall sites, measured rates of ferric iron reduction could account for up to 44 % of organic carbon oxidation. Iron reducers appeared to compete with methanogens when labile carbon availability was limited. We found large numbers of bacteria that oxidize reduced iron at sites with high rates of iron reduction and large numbers of iron-reducers. the coexistence of large populations of ironreducing and iron-oxidizing bacteria is evidence for rapid iron cycling between its reduced and oxidized states, and suggests that mutualistic interactions among these bacteria ultimately fuel organic carbon oxidation and inhibit CH4 production in these upland tropical forests.

  19. Tropical mountain cradles of dry forest diversity Christopher W. Dick*

    E-Print Network [OSTI]

    Bermingham, Eldredge

    * *Smithsonian Tropical Research Institute, Apartado 0843-03092, Balboa, Panama´; and Department of Ecology radiated at vastly different times, so fo- cus on a single taxon would be mislead- ing. On the side of rain- ple, the dry forest legume clade Leu- caena underwent endemic radiation in southwest Mexico beginning

  20. Transport of carbon monoxide from the tropics to the extratropics

    E-Print Network [OSTI]

    November), biomass burning in the southern tropics produces large-scale plumes of CO. These plumes can biomass-burning regions generally rises into the middle and upper troposphere, where it is entrained. For example, it is now clear that the main population areas in the northern hemisphere (North America, Europe

  1. 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 ...

  2. Our Visit To The Holy Apostle Soup Kitchen: Touching Real People With Real Stories By Ashley Olson

    E-Print Network [OSTI]

    Wisconsin at Madison, University of

    instructor was in charge of greeting people at the entryway. Many times she saw guests give hugs and kissesOur Visit To The Holy Apostle Soup Kitchen: Touching Real People With Real Stories By Ashley Olson Our visit to the Holy Apostle Soup Kitchen defined my experience in New York City. People came from

  3. Three-Year Non-Tenure Track Visiting Assistant Professor Position Geophysics -The University of Alabama Department of Geological

    E-Print Network [OSTI]

    Zheng, Chunmiao

    Three-Year Non-Tenure Track Visiting Assistant Professor Position ­ Geophysics - The University of Alabama invites applications for a three-year, non-tenure track visiting faculty position in geophysics geophysical sub-disciplines, preference will be given to candidates who will enhance our existing geophysics

  4. 1CDF-LBNL Status. J. Kogut visit, 10/09/07, Lina Galtieri The CDF Group at LBNL

    E-Print Network [OSTI]

    Galtieri, Lina

    1CDF-LBNL Status. J. Kogut visit, 10/09/07, Lina Galtieri The CDF Group at LBNL Outline Past and Conclusions Expected Tev luminosity to FY'09 CDFII Detector LBNL contribution on: silicon detector and COT tracker #12;2CDF-LBNL Status. J. Kogut visit, 10/09/07, Lina Galtieri Contributions since 1981 Joined

  5. THE MAGNETIC CONNECTION BETWEEN THE CONVECTION ZONE AND CORONA IN THE QUIET SUN

    E-Print Network [OSTI]

    Abbett, Bill

    THE MAGNETIC CONNECTION BETWEEN THE CONVECTION ZONE AND CORONA IN THE QUIET SUN W. P. Abbett Space connection between the convectively unstable layers below the visible surface of the Sun and the overlying application of this numerical model, we present a series of simulations of the quiet Sun in a domain

  6. Linear control and estimation of nonlinear chaotic convection: Harnessing the butterfly effect

    E-Print Network [OSTI]

    Bewley, Thomas

    Linear control and estimation of nonlinear chaotic convection: Harnessing the butterfly effect/robust control theory to a low-order nonlinear chaotic convection problem. Linear control feedback is found before control is applied. Linear estimator feedback is found to be fully effective only when

  7. Improving Simulations of Convective Systems from TRMM LBA: Easterly and Westerly Regimes

    E-Print Network [OSTI]

    Rutledge, Steven

    ) experiment in Brazil. These two events epitomized the type of convective systems that formed in two a sheared low-level easterly wind flow. On 23 February 1999, convection developed in weak low-level westerly-scale models. A central objective of the Global Energy and Water-Cycle Experiment (GEWEX) Cloud System Study

  8. 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...

  9. Improving Convection Parameterization Using ARM Observations and NCAR Community Atmosphere Model

    SciTech Connect (OSTI)

    Zhang, Guang J [Scripps Institution of Oceanography

    2013-07-29T23:59:59.000Z

    Highlight of Accomplishments: We made significant contribution to the ASR program in this funding cycle by better representing convective processes in GCMs based on knowledge gained from analysis of ARM/ASR observations. In addition, our work led to a much improved understanding of the interaction among aerosol, convection, clouds and climate in GCMs.

  10. Modelling the convective flow in solar thermal receivers K.C. Yeh; G. Hughes & K. Lovegrove

    E-Print Network [OSTI]

    value energy conversions such as heat engine cycles or chemical process to be carried outModelling the convective flow in solar thermal receivers K.C. Yeh; G. Hughes & K. Lovegrove, Canberra AUSTRALIA E-mail: u3370739@anu.edu.au The natural convective flow inside a concentrating solar

  11. Numerical study of natural convection in a vertical porous annulus with discrete heating

    E-Print Network [OSTI]

    Lopez, John M.

    Numerical study of natural convection in a vertical porous annulus with discrete heating M. Sankar online 20 December 2010 Keywords: Natural convection Annulus Discrete heating Porous medium Radii ratio to discrete heating. The outer wall is maintained iso- thermally at a lower temperature, while the top

  12. 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

  13. 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

  14. 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

  15. THE BASE OF THE CONVECTION ZONE AND THE SOLAR MAGNETIC CYCLE: SEISMIC DETECTION OF THEIR CONNECTION

    E-Print Network [OSTI]

    Monteiro, Mário João

    495 THE BASE OF THE CONVECTION ZONE AND THE SOLAR MAGNETIC CYCLE: SEISMIC DETECTION Unit, School of Mathematical Sciences, Queen Mary & Westfield College, Mile End Road, London El 4NS of the transition at the bot- tom of the solar convection zone, as determined from the periodic signal

  16. PARAMETERS OF THE SOLAR CONVECTION ZONE IN EVOLUTIONARY AND SEISMIC MODELS

    E-Print Network [OSTI]

    PARAMETERS OF THE SOLAR CONVECTION ZONE IN EVOLUTIONARY AND SEISMIC MODELS VLADIMIR A. BATURIN Queen Mary & Westfield College, Mile End Road, London E1 4NS, UK AND SERGEY V. AYUKOV Sternberg of the entropy of the adiabatic part of the solar convection zone are compared. Key words: solar physics

  17. Global Gevrey Regularity for the B'enard Convection in Porous Medium with Zero

    E-Print Network [OSTI]

    Global Gevrey Regularity for the B'enard Convection in Porous Medium with Zero Darcy­Prandtl Number for the three­dimensional B'enard convection model in porous medium with zero Darcy­Prandtl number using system for energy conservation, enhancing recovery of oil by thermal methods, assessing risks for nuclear

  18. Simulated Convective Invigoration Processes at Trade Wind Cumulus Cold Pool ZHUJUN LI AND PAQUITA ZUIDEMA

    E-Print Network [OSTI]

    Zuidema, Paquita

    convection and cold pools using a nested­Weather Research and Fore- casting Model simulation of 19 January ratio drops in simulated cold pools fall within the envelope of observed cases, and the wind enhancement pools invigorating convection at their downwind boundary and suppressing thermals in- side the stable

  19. A Fourier-spectral element algorithm for thermal convection in rotating axisymmetric containers

    E-Print Network [OSTI]

    Fournier, Alexandre

    A Fourier-spectral element algorithm for thermal convection in rotating axisymmetric containers Abstract We present a Fourier-spectral element approach for modeling thermal convection in a rotating, Spectral Methods for Axisymmetric Domains, Gauthier-Villars, Paris, 1999], a Fourier expansion of the field

  20. Convective heat transfer as a function of wavelength: Implications for the cooling of the Earth

    E-Print Network [OSTI]

    Convective heat transfer as a function of wavelength: Implications for the cooling of the Earth C, in particular, on its variation with the wavelength of convection. The heat transfer strongly depends in Earth's mantle can significantly reduce the efficiency of heat transfer. The likely variations

  1. EulerianEulerian two-phase numerical simulation of nanofluid laminar forced convection in a microchannel

    E-Print Network [OSTI]

    Harting, Jens

    Eulerian­Eulerian two-phase numerical simulation of nanofluid laminar forced convection August 2010 Accepted 5 August 2010 Keywords: Nanofluid Microchannel Two-phase Laminar Heat transfer a b s t r a c t In this paper, laminar forced convection heat transfer of a copper­water nanofluid inside

  2. Dielectrophoretic Rayleigh-Benard convection under microgravity conditions H. N. Yoshikawa,

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    conditions. A thermo-electric coupling resulting from the thermal variation of the electric permittivity of the fluid produces the dielectrophoretic (DEP) body force, which can be regarded as thermal buoyancy due of the GL equation are comparable with those for the RB convection. The heat transfer in the DEP convection

  3. Kinetics of the clay roofing tile convection drying

    SciTech Connect (OSTI)

    Thomas, S. (Univ. of Osijek (Croatia). Faculty of Food Technology); Skansi, D. (Univ. of Zagreb (Croatia). Faculty of Chemical Engineering and Technology); Sokele, M. (Croatian Post and Telecommunications, Zagreb (Croatia). Telecommunications Center)

    1993-01-01T23:59:59.000Z

    Kinetics of the convection drying process of flat tile has been investigated experimentally in an industrial tunnel dryer. Several velocities of wet tile movement through the dryer were tested to obtain maximum allowable drying rate curve. As there are various models to describe the kinetics of convection drying, finding a model that would fairly well approximate the kinetics of the whole drying process was part of the research. Especially the polynomial and exponential models were tested. It was found that exponential model of the type: B(t) = (a[minus]B[sub e])[center dot]EXP([minus]bt[sup 2])+B[sub e], ([minus]dB(t)/dt) = 2bt(B(t)[minus]B[sub e]) significantly correlates the kinetics of the whole tile drying process. Applying the maximum allowable drying rate curve obtained for flat tile in the first period of drying, a grapho-analytic model for the optimal conducting of the process has been developed.

  4. A Multiscale Dynamo Model Driven by Quasi-geostrophic Convection

    E-Print Network [OSTI]

    Calkins, Michael A; Tobias, Steven M; Aurnou, Jonathan M

    2015-01-01T23:59:59.000Z

    A convection-driven multiscale dynamo model is developed for the plane layer geometry in the limit of low Rossby number. The small-scale fluctuating dynamics are described by a magnetically-modified quasi-geostrophic equation set, and the large-scale mean dynamics are governed by a diagnostic thermal wind balance. The model utilizes three timescales that respectively characterize the convective timescale, the large-scale magnetic diffusion timescale, and the large-scale thermal diffusion timescale. Distinct equations are derived for the cases of order one and low magnetic Prandtl number. It is shown that the low magnetic Prandtl number model is characterized by a magnetic to kinetic energy ratio that is asymptotically large, with ohmic dissipation dominating viscous dissipation on the large-scales. For the order one magnetic Prandtl number model the magnetic and kinetic energies are equipartitioned and both ohmic and viscous dissipation are weak on the large-scales; large-scale ohmic dissipation occurs in thi...

  5. Particle filter based on thermophoretic deposition from natural convection flow

    SciTech Connect (OSTI)

    Sasse, A.G.B.M.; Nazaroff, W.W. (Univ. of California, Berkeley, CA (United States)); Gadgil, A.J. (Lawrence Berkeley Lab., CA (United States))

    1994-04-01T23:59:59.000Z

    We present an analysis of particle migration in a natural convection flow between parallel plates and within the annulus of concentric tubes. The flow channel is vertically oriented with one surface maintained at a higher temperature than the other. Particle migration is dominated by advection in the vertical direction and thermophoresis in the horizontal direction. From scale analysis it is demonstrated that particles are completely removed from air flowing through the channel if its length exceeds L[sub c] = (b[sup 4]g/24K[nu][sup 2]), where b is the width of the channel, g is the acceleration of gravity, K is a thermophoretic coefficient of order 0.5, and [nu] is the kinematic viscosity of air. Precise predictions of particle removal efficiency as a function of system parameters are obtained by numerical solution of the governing equations. Based on the model results, it appears feasible to develop a practical filter for removing smoke particles from a smoldering cigarette in an ashtray by using natural convection in combination with thermophoresis. 22 refs., 8 figs., 1 tab.

  6. ARM - Midlatitude Continental Convective Clouds (jensen-sonde)

    SciTech Connect (OSTI)

    Jensen, Mike; Comstock, Jennifer; Genio, Anthony Del; Giangrande, Scott; Kollias, Pavlos

    2012-01-19T23:59:59.000Z

    A major component of the Mid-latitude Continental Convective Clouds Experiment (MC3E) field campaign was the deployment of an enhanced radiosonde array designed to capture the vertical profile of atmospheric state variables (pressure, temperature, humidity wind speed and wind direction) for the purpose of deriving the large-scale forcing for use in modeling studies. The radiosonde array included six sites (enhanced Central Facility [CF-1] plus five new sites) launching radiosondes at 3-6 hour sampling intervals. The network will cover an area of approximately (300)2 km2 with five outer sounding launch sites and one central launch location. The five outer sounding launch sites are: S01 Pratt, KS [ 37.7oN, 98.75oW]; S02 Chanute, KS [37.674, 95.488]; S03 Vici, Oklahoma [36.071, -99.204]; S04 Morris, Oklahoma [35.687, -95.856]; and S05 Purcell, Oklahoma [34.985, -97.522]. Soundings from the SGP Central Facility during MC3E can be retrieved from the regular ARM archive. During routine MC3E operations 4 radiosondes were launched from each of these sites (approx. 0130, 0730, 1330 and 1930 UTC). On days that were forecast to be convective up to four additional launches were launched at each site (approx. 0430, 1030, 1630, 2230 UTC). There were a total of approximately 14 of these high frequency launch days over the course of the experiment.

  7. ARM - Midlatitude Continental Convective Clouds (jensen-sonde)

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

    Jensen, Mike; Comstock, Jennifer; Genio, Anthony Del; Giangrande, Scott; Kollias, Pavlos

    A major component of the Mid-latitude Continental Convective Clouds Experiment (MC3E) field campaign was the deployment of an enhanced radiosonde array designed to capture the vertical profile of atmospheric state variables (pressure, temperature, humidity wind speed and wind direction) for the purpose of deriving the large-scale forcing for use in modeling studies. The radiosonde array included six sites (enhanced Central Facility [CF-1] plus five new sites) launching radiosondes at 3-6 hour sampling intervals. The network will cover an area of approximately (300)2 km2 with five outer sounding launch sites and one central launch location. The five outer sounding launch sites are: S01 Pratt, KS [ 37.7oN, 98.75oW]; S02 Chanute, KS [37.674, 95.488]; S03 Vici, Oklahoma [36.071, -99.204]; S04 Morris, Oklahoma [35.687, -95.856]; and S05 Purcell, Oklahoma [34.985, -97.522]. Soundings from the SGP Central Facility during MC3E can be retrieved from the regular ARM archive. During routine MC3E operations 4 radiosondes were launched from each of these sites (approx. 0130, 0730, 1330 and 1930 UTC). On days that were forecast to be convective up to four additional launches were launched at each site (approx. 0430, 1030, 1630, 2230 UTC). There were a total of approximately 14 of these high frequency launch days over the course of the experiment.

  8. Numerical analysis of heat transfer by conduction and natural convection in loose-fill fiberglass insulation--effects of convection on thermal performance

    SciTech Connect (OSTI)

    Delmas, A.A.; Wilkes, K.E.

    1992-04-01T23:59:59.000Z

    A two-dimensional code for solving equations of convective heat transfer in porous media is used to analyze heat transfer by conduction and convection in the attic insulation configuration. The particular cases treated correspond to loose-fill fiberglass insulation, which is characterized by high porosity and air permeability. The effects of natural convection on the thermal performance of the insulation are analyzed for various densities, permeabilities, and thicknesses of insulation. With convection increasing the total heat transfer through the insulation, the thermal resistance was found to decrease as the temperature difference across the insulating material increases. The predicted results for the thermal resistance are compared with data obtained in the large-scale climate simulator at the Roof Research Center using the attic test module, where the same phenomenon has already been observed. The way the wood joists within the insulation influence the start of convection is studied for differing thermophysical and dynamic properties of the insulating material. The presence of wood joists induces convection at a lower temperature difference.

  9. 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

  10. Magnetospheric Convection The large-scale flow of rarefied plasma in the Earth's magnetosphere "is quite analogous to

    E-Print Network [OSTI]

    Michigan, University of

    quite analogous to thermal convection" (Gold, 1959); therefore, the term "convection" is commonly used of geomagnetic field lines in the crossed E and B fields. By analogy with the thermal convection in a non in the magnetosheath: a region between the bow shock and the magnetopause. A similar flow pattern is formed

  11. Accepted by Mon. Weather Rev. December 17, 1998. Convective Precursors and Predictability in the

    E-Print Network [OSTI]

    Sherwood, Steven

    in the Tropics are investigated by multivariate analysis of sounding and satellite data from the tropical western because it has been considered more complex and less well-understood than the activation problem, NASA Goddard Space Flight Center, Mail Code 916, Greenbelt, MD 20771 (ssherwood@alum.mit.edu) Many

  12. Wind reversals in turbulent Rayleigh-Benard convection

    E-Print Network [OSTI]

    Francisco Fontenele Araujo; S. Grossmann; D. Lohse

    2005-08-29T23:59:59.000Z

    The phenomenon of irregular cessation and subsequent reversal of the large-scale circulation in turbulent Rayleigh-B\\'enard convection is theoretically analysed. The force and thermal balance on a single plume detached from the thermal boundary layer yields a set of coupled nonlinear equations, whose dynamics is related to the Lorenz equations. For Prandtl and Rayleigh numbers in the range $10^{-2} \\leq \\Pr \\leq 10^{3}$ and $10^{7} \\leq \\Ra \\leq 10^{12}$, the model has the following features: (i) chaotic reversals may be exhibited at Ra $\\geq 10^{7}$; (ii) the Reynolds number based on the root mean square velocity scales as $\\Re_{rms} \\sim \\Ra^{[0.41 ... 0.47]}$ (depending on Pr), and as $\\Re_{rms} \\sim \\Pr^{-[0.66 ... 0.76]}$ (depending on Ra); and (iii) the mean reversal frequency follows an effective scaling law $\\omega / (\

  13. Experimental Investigation of Natural Convection in Trombe Wall Systems 

    E-Print Network [OSTI]

    Chen, B.; Zhao, J.; Chen, C.; Zhuang, Z.

    2006-01-01T23:59:59.000Z

    :0010:0011:0012:0013:0014:00 15:0016:0017:00 5 10 15 20 25 30 35 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 11/21 Solar radiant intensity[kW/m 2 ] Temperature[ ? ] Time Tr Tfu Twi Ta ------- I Fig. 2 Daily variation of Tr, Tfu, Twi , Ta , I and ? f... regarded that Gr~109 -3?Pr ?10 3? is the transition criterion as the natural convection flow from laminar to turbulent [12]. Experimental data from four sunny days (11.20, 11.21, 11.27, 11.28) with normal thermo-circulation (9:00-16:00) is utilized...

  14. Operating temperatures for a convectively cooled recessed incandescent light fixture

    SciTech Connect (OSTI)

    Yarbrough, D.W.; Toor, I.

    1980-12-01T23:59:59.000Z

    Test results are given for the operation of a recessed incandescent light fixture intended for residential use. The fixture is labeled for use in direct contact with attic thermal insulation. Temperature control of the powered fixture is provided by convective heat transfer from the ceiling side of the fixture. The fixture was operated at power levels up to two times the rated power of 75 watts and under thermal insulations up to R-40. In all operating configurations tested the fixture surface in contact with attic insulation was found to be less than 175/sup 0/C. The observed surface temperatures are judged to be safe for operation in contact with loose-fill or batt-type insulations. It was observed that the power leads inside one fixture configuration are exposed to temperatures as high as 168/sup 0/C. The electrical insulation could, therefore, have a limited life. The properties of the internal fixture wiring were not, however, studied in detail.

  15. Apparatus for production of synthesis gas using convective reforming

    SciTech Connect (OSTI)

    Karafian, M.; Tsang, I.C.

    1991-04-09T23:59:59.000Z

    This patent describes a system for the steam reforming of hydrocarbons into a hydrogen-rich gas. It comprises a convective reformer device having indirect heat exchange means for partially reforming a feed mixture of hydrocarbons and steam; a steam reforming furnace having a radiant section, reforming tubes in the radiant section, and means for producing radiant heat for the further reforming of the partially reformed effluent; an auto-thermal reformer for fully reforming the effluent; conduit means for passing the partially reformed effluent; conduit means for passing the effluent; and conduit means for passing the fully reformed effluent to supply the heat of reaction for the partial reformation of the hydrocarbon-steam feed mixture.

  16. Stability of sunspots to convective motions. I. Adiabatic instability

    SciTech Connect (OSTI)

    Moreno-Insertis, F.; Spruit, H.C. (Instituto de Astrofisica de Canarias, La Laguna (Spain); Max-Planck-Institut fuer Physik und Astrophysik, Garching (Germany, F.R.))

    1989-07-01T23:59:59.000Z

    For determining the adiabatic stability of a uniform vertical field in an arbitrary stratification it is sufficient to consider the limit of infinitesimal horizontal wavelength. It is shown how the behavior of the instability can be estimated qualitatively from the dependence of the equipartition field strength on depth. Modes are calculated numerically for analytic stratification models and for a detailed sunspot stratification, including the effects of partial ionization. It is concluded that for the observed field strengths of umbrae the stratification is indeed unstable, with a growth time of about 18 minutes. The unstable eigenfunctions have a maximum at about 2300 km below the surface of the umbra and are about 3900 km deep. Deeper layers may also be unstable depending on unknown details of the stratification. A connection between fluting instability and convective instability is noted. 37 refs.

  17. TURBULENT CONVECTION IN STELLAR INTERIORS. III. MEAN-FIELD ANALYSIS AND STRATIFICATION EFFECTS

    SciTech Connect (OSTI)

    Viallet, Maxime [Physics and Astronomy, University of Exeter, Stocker Road, Exeter, EX4 4QL (United Kingdom); Meakin, Casey; Mocak, Miroslav [Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Arnett, David [Steward Observatory, University of Arizona, Tucson, AZ 85721 (United States)

    2013-05-20T23:59:59.000Z

    We present three-dimensional implicit large eddy simulations of the turbulent convection in the envelope of a 5 M{sub Sun} red giant star and in the oxygen-burning shell of a 23 M{sub Sun} supernova progenitor. The numerical models are analyzed in the framework of one-dimensional Reynolds-Averaged Navier-Stokes equations. The effects of pressure fluctuations are more important in the red giant model, owing to larger stratification of the convective zone. We show how this impacts different terms in the mean-field equations. We clarify the driving sources of kinetic energy, and show that the rate of turbulent dissipation is comparable to the convective luminosity. Although our flows have low Mach numbers and are nearly adiabatic, our analysis is general and can be applied to photospheric convection as well. The robustness of our analysis of turbulent convection is supported by the insensitivity of the mean-field balances to linear mesh resolution. We find robust results for the turbulent convection zone and the stable layers in the oxygen-burning shell model, and robust results everywhere in the red giant model, but the mean fields are not well converged in the narrow boundary regions (which contain steep gradients) in the oxygen-burning shell model. This last result illustrates the importance of unresolved physics at the convective boundary, which governs the mixing there.

  18. The divergent wind component in data sparse tropical wind fields 

    E-Print Network [OSTI]

    Snyder, Bruce Alan

    1985-01-01T23:59:59.000Z

    boundary data were estimated by linear extrapolation from inner to outer grid points. Comparisons of level Illb wind data and cloud drift winds were made using Geostationary Operational Environmental Satelhte (GOES) West observed winds obtained from... for 0000 GMT 25 January 1979 were drawn and subjectively compared. Claudy regions viewed in enhanced GOES West imagery were superimposed on these streamline fields to determine whether the aliased wind fields correlated well with the convective activity...

  19. Interactions between Cumulus Convection and Its Environment as Revealed by the MC3E Sounding Array

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

    Xie, Shaocheng; Jensen, Michael P.; Zhang, Yunyan; Giangrande, Scott E.; McCoy, Renata; Zhang, Minghua

    2014-10-27T23:59:59.000Z

    This study attempts to understand interactions between midlatitude convective systems and their environments through a heat and moisture budget analysis using the sounding data collected from the Midlatitude Continental Convective Clouds Experiment (MC3E) in central Oklahoma. Distinct large-scale structures and diabatic heating and drying profiles are presented for cases of weaker and elevated thunderstorms as well as intense squall line and supercell thunderstorm events during the campaign. The elevated cell events were nocturnal convective systems occurring in an environment having low convective available potential energy (CAPE) and a very dry boundary layer. In contrast, deeper convective events happened during themore »morning into early afternoon within an environment associated with large CAPE and a near-saturated boundary layer. As the systems reached maturity, the diagnosed diabatic heating in the latter deep convective cases was much stronger and of greater vertical extent than the former. Both groups showed considerable diabatic cooling in the lower troposphere, associated with the evaporation of precipitation and low-level clouds. The horizontal advection of moisture also played a dominant role in moistening the lower troposphere, particularly for the deeper convective events, wherein the near surface southeasterly flow allows persistent low-level moisture return from the Gulf of Mexico to support convection. The moisture convergence often was present before these systems develop, suggesting a strong correlation between the large-scale moisture convergence and convection. Sensitivity tests indicated that the uncertainty in the surface precipitation and the size of analysis domain mainly affected the magnitude of these analyzed fields rather than their vertical structures.« less

  20. Interactions between Cumulus Convection and Its Environment as Revealed by the MC3E Sounding Array

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

    Xie, Shaocheng [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States); Jensen, Michael P. [Brookhaven National Laboratory (BNL), Upton, NY (United States); Zhang, Yunyan [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States); Giangrande, Scott E. [Brookhaven National Laboratory (BNL), Upton, NY (United States); McCoy, Renata [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States); Zhang, Minghua [Stony Brook Univ., Stony Brook, NY (United States)

    2014-10-27T23:59:59.000Z

    This study attempts to understand interactions between midlatitude convective systems and their environments through a heat and moisture budget analysis using the sounding data collected from the Midlatitude Continental Convective Clouds Experiment (MC3E) in central Oklahoma. Distinct large-scale structures and diabatic heating and drying profiles are presented for cases of weaker and elevated thunderstorms as well as intense squall line and supercell thunderstorm events during the campaign. The elevated cell events were nocturnal convective systems occurring in an environment having low convective available potential energy (CAPE) and a very dry boundary layer. In contrast, deeper convective events happened during the morning into early afternoon within an environment associated with large CAPE and a near-saturated boundary layer. As the systems reached maturity, the diagnosed diabatic heating in the latter deep convective cases was much stronger and of greater vertical extent than the former. Both groups showed considerable diabatic cooling in the lower troposphere, associated with the evaporation of precipitation and low-level clouds. The horizontal advection of moisture also played a dominant role in moistening the lower troposphere, particularly for the deeper convective events, wherein the near surface southeasterly flow allows persistent low-level moisture return from the Gulf of Mexico to support convection. The moisture convergence often was present before these systems develop, suggesting a strong correlation between the large-scale moisture convergence and convection. Sensitivity tests indicated that the uncertainty in the surface precipitation and the size of analysis domain mainly affected the magnitude of these analyzed fields rather than their vertical structures.