National Library of Energy BETA

Sample records for tropical convection visiting

  1. Layer inflow into precipitating convection over the western tropical Pacific

    E-Print Network [OSTI]

    Mechem, David B.; Houze, Robert A. Jr.; Chen, Shuyi S.

    2002-07-01

    A conceptual model of tropical convection frequently used in convective parametrization schemes is that of a parcel process in which boundary-layer air, characterized by high equivalent potential temperature, ascends to ...

  2. 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

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

    E-Print Network [OSTI]

    Lutz, Kurt Reed

    1992-01-01

    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... of the requirements for the degree of MASTER OF SCIENCE December 1992 Major Subject: Meteorology VERTICAL PROFILES OF RADAR REFLECTIVITY OF CONVECTIVE CELLS IN TROPICAL AND MID-LATITUDE MESOSCALE CONVECTIVE SYSTEMS A Thesis by KURT REED LUTZ Approved...

  4. Geographical distribution and interseasonal variability of tropical deep convection: UARS MLS observations and analyses

    E-Print Network [OSTI]

    Wang, Bin

    of water vapor maxima near the bottom of TTL are located directly above the deep convection centersGeographical distribution and interseasonal variability of tropical deep convection: UARS MLS December 2003; published 13 February 2004. [1] Tropical deep convection and its dynamical effect

  5. Effect of Convective Entrainment/Detrainment on the Simulation of the Tropical Precipitation Diurnal Cycle*

    E-Print Network [OSTI]

    Wang, Yuqing

    Effect of Convective Entrainment/Detrainment on the Simulation of the Tropical Precipitation the effect of assumed fractional convective entrainment/detrainment rates in the Tiedtke mass flux convective measurements. In a control experiment with the default fractional convective entrainment/detrainment rates

  6. 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

  7. 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

  8. Reproducibility by Climate Models of Cloud Radiative Forcing Associated with Tropical Convection

    E-Print Network [OSTI]

    Masunaga, Hirohiko

    for monthly mean data from twentieth-century simulations of 18 climate models participating in phase 3 perturbation is thus fundamental for our understanding of climate change, but shows no consistency in eitherReproducibility by Climate Models of Cloud Radiative Forcing Associated with Tropical Convection

  9. 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.

    2013-08-01

    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.

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

    SciTech Connect (OSTI)

    Schumacher, Courtney

    2012-12-13

    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.

  11. Convective Entrainment and Large-Scale Organization of Tropical Precipitation: Sensitivity of the CNRM-CM5 Hierarchy of Models

    E-Print Network [OSTI]

    Convective Entrainment and Large-Scale Organization of Tropical Precipitation: Sensitivity explore this sensitivity, the authors focus in this study on the influence of lateral entrainment to the entrainment parameter were performed in a hierarchy of models (coupled ocean­ atmosphere GCM, atmospheric GCM

  12. Tropical cyclone size in observations and in radiative-convective equilibrium

    E-Print Network [OSTI]

    Chavas, Daniel Robert

    2013-01-01

    Tropical cyclone size remains an unsolved problem in tropical meteorology, yet size plays a significant role in the damage caused by tropical cyclones due to wind, storm surge, and inland freshwater flooding. This work ...

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

    E-Print Network [OSTI]

    Chavas, Daniel Robert

    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 ...

  14. 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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would like submit the followingConcentratingPortal ControllingConvection feedbacks in a What

  15. 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

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

    E-Print Network [OSTI]

    McGaughey, Gary Rae

    1994-01-01

    the Advanced Microwave Precipitation Radiometer (AMPR) aboard the NASA ER2 during the Tropical Ocean and Global Atmosphere Coupled-Ocean Atmosphere Response Experiment (TOGA-COARE). The AMPR measures linearly polarized radiation at 10.7, 19.35, 37. 1, and 85...

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

    E-Print Network [OSTI]

    Hernandez, Celina Anne

    2009-05-15

    . THE QBO?S INFLUENCE ON LIGHTING PRODUCTION IN THE TROPICS ................................................................................................................ 10 3.1 Africa... lightning flash densities observed over land (Fig.8). Therefore, this analysis focuses on four land regions: Africa, India, Maritime continent/Australia, and South America. 3.1 Africa West minus east flash density anomalies for DJF (Fig. 9a) show...

  18. 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

    2012-10-02

    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.

  19. The relationship between atmospheric convective radiative effect and net1 energy transport in the tropical warm pool2

    E-Print Network [OSTI]

    Hartmann, Dennis

    of the atmospheric cloud radiative effect in determining the magnitude of hor- izontal export of energy, they increase the re- quirement for the atmosphere to export energy from convective regions. Over the warmest that the increased energy export is supplied by the radiative heating from convection. The net cloud radiative effect

  20. 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

  1. 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-

    2007-01-01

    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 ...

  2. 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

    2014-05-16

    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.

  3. Visiting ORNL

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

    or 865.574.7199. Before Arriving Entering ORNL Deliveries to ORNL Building Access Wireless Networking Tours Other Tours Research Visits What you must bring Entry Pass Visa...

  4. The Dynamics and Predictability of Tropical Cyclones 

    E-Print Network [OSTI]

    Sippel, Jason A.

    2010-01-15

    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 ...

  5. Diurnal analysis of intensity trends in Atlantic tropical cyclones

    E-Print Network [OSTI]

    Kowch, Roman S

    2013-01-01

    I postulate that a diurnal cycle may exist in observational variables related to tropical cyclone (TC) intensity. Prior studies document a significant diurnal signal in moist convection across tropical regions. Since ...

  6. 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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory ofDidDevelopmentat LENA|UpcomingVisit Us Download the NIF Visitor's

  7. 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

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

    E-Print Network [OSTI]

    Restivo, Michael Edward

    1995-01-01

    The TOGA COARE experiment was carried out in the western Pacific warm pool region from November 1992 through February 1993. Data from TOGA COARE provide the opportunity for comprehensive studies of tropical oceanic convection. ...

  9. Climate Science in the Tropics: Waves, Vortices, Boualem Khouider1

    E-Print Network [OSTI]

    Stechmann, Samuel N.

    Climate Science in the Tropics: Waves, Vortices, and PDEs Boualem Khouider1 , Andrew J Majda2 and climate on the entire globe, yet contemporary operational computer models are often deficient.10 Keywords: Climate science, Tropical meteorology, waves, vortices, convection, PDEs, MJO, GCMs, tropical

  10. The frequency of tropical precipitating clouds as observed by the TRMM PR and ICESat/GLAS 

    E-Print Network [OSTI]

    Casey, Sean Patrick

    2009-06-02

    Convective clouds in the tropics can be grouped into three categories: shallow clouds with cloud-top heights near 2 km above the surface, mid-level congestus clouds with tops near the 0°C level, and deep convective clouds ...

  11. Extreme Summer Convection in South America ULRIKE ROMATSCHKE

    E-Print Network [OSTI]

    Houze Jr., Robert A.

    -level suppressed flow of the southeast Pacific from the unstable low-level flow dominating weather over. Knowledge of the details of convection throughout the tropics and subtropics has been revolutionized

  12. Reactor Engineering: Experimental Investigation of Alpha Convection

    SciTech Connect (OSTI)

    Usman, Shoaib

    2012-10-12

    Natural convection, Rayleigh-Bernard convection, Transient convection and Conduction convection transition.

  13. Convection towers

    DOE Patents [OSTI]

    Prueitt, M.L.

    1996-01-16

    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.

  14. Convection towers

    DOE Patents [OSTI]

    Prueitt, Melvin L. (Los Alamos, NM)

    1995-01-01

    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.

  15. Convection towers

    DOE Patents [OSTI]

    Prueitt, Melvin L. (Los Alamos, NM)

    1994-01-01

    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.

  16. Convection towers

    DOE Patents [OSTI]

    Prueitt, Melvin L. (Los Alamos, NM)

    1996-01-01

    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.

  17. Convection towers

    DOE Patents [OSTI]

    Prueitt, M.L.

    1994-02-08

    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.

  18. CHARACTERIZATION OF CLOUDS IN TITAN'S TROPICAL ATMOSPHERE

    SciTech Connect (OSTI)

    Griffith, Caitlin A.; Penteado, Paulo; Rodriguez, Sebastien; Baines, Kevin H.; Buratti, Bonnie; Sotin, Christophe; Clark, Roger; Nicholson, Phil; Jaumann, Ralf

    2009-09-10

    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.

  19. Home Weatherization Visit

    Broader source: Energy.gov [DOE]

    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...

  20. Convective heater

    DOE Patents [OSTI]

    Thorogood, Robert M. (Macungie, PA)

    1986-01-01

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

  1. Home Weatherization Visit

    ScienceCinema (OSTI)

    Chu, Steven

    2013-05-29

    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.

  2. Congressman Clyburn Visit

    ScienceCinema (OSTI)

    Cody, Tom

    2012-06-14

    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.

  3. 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 or in tropical and arid countries. In this work, radiation, convection and conduction heat transfers-dimensional numerical simulation of the heat transfers through the double skin reveals the most important parameters

  4. Analysis of TRMM Precipitation Radar Algorithms and Rain over the Tropics and Southeast Texas 

    E-Print Network [OSTI]

    Funk, Aaron

    2013-12-10

    The Tropical Rainfall Measuring Mission (TRMM) Precipitation Radar (PR) 2A23 algorithm classifies rain echo as stratiform or convective while the 2A25 algorithm corrects vertical profiles of radar reflectivity for attenuation ...

  5. Visit the Museum

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    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservationBio-Inspired SolarAbout /Two0 -UsingHeat & Cool History FusionVisit the Museum

  6. Visiting | Advanced Photon Source

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  7. When to Visit

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  8. ARM - Visiting the SGP

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    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Comments?govInstrumentsnoaacrnBarrow,ProductstoacessProductsrlprofrlprofmerge1turnPlainsVisiting the SGP SGP

  9. ARM - Visiting the TWP

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  10. Visiting NREL | NREL

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    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory ofDidDevelopmentat LENA|UpcomingVisit Us Download the NIF

  11. Visiting Scientists and Professionals

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    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory ofDidDevelopmentat LENA|UpcomingVisit Us Download the NIF PPPL Area

  12. ORISE: Visiting Us

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  13. 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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking WithTelecentricN A CountyFeet) Cooley PoliciesAdditionalVisiting

  14. Plan Your Visit

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  15. 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

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

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

    Jensen, Michael

    2014-04-10

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

  17. 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;

  18. The efficiency of diabatic heating and tropical cyclone intensification

    E-Print Network [OSTI]

    Smith, Roger K.

    The efficiency of diabatic heating and tropical cyclone intensification Roger K. Smitha and Michael cyclones to the increasing "efficiency" of diabatic heating in the cyclone's inner core region associated with deep convection. The efficiency, in essence the amount of temperature warming compared to the amount

  19. University of Delaware | CCEI Visiting Scholars

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

    Visiting Scholars Adriano Freitas de Sousa- Visiting Student Universidade Federal do Cear Advisor: Vlachos, Dion Office: 367 ISE Lab Phone: (302) 831-4061 Email: Send email...

  20. Unclassified Foreign Visits and Assignments

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

    2004-06-18

    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

  1. ACADEMIC DELEGATION VISITS 2008 -2014

    E-Print Network [OSTI]

    Di Pillo, Gianni

    Total Visits: 38 Europe: Kosovo, Germany, Estonia, Romania, Turkey, Belarus Asia: Kazakhstan, Russia: Austria, Germany, Slovenia, Turkey, United Kingdom, Sweden, Hungary, France, Albania Asia: Kazakhstan: 54 Europe: Turkey, Czech Republic, Germany, Kosovo, Hungary, Romania, Serbia, Netherlands, Croatia

  2. Unclassified Foreign Visits and Assignments

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

    1999-07-14

    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

  3. 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.

    2015-01-06

    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 forcingmore »is weak. 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

  4. 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.

    2015-01-06

    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

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

    SciTech Connect (OSTI)

    Storer, R. L. [Univ. of Wisconsin - Milwaukee, Milwaukee, WI (United States); Griffin, B. M. [Univ. of Wisconsin - Milwaukee, Milwaukee, WI (United States); Höft, J. [Univ. of Wisconsin - Milwaukee, Milwaukee, WI (United States); Weber, J. K. [Univ. of Wisconsin - Milwaukee, Milwaukee, WI (United States); Raut, E. [Univ. of Wisconsin - Milwaukee, Milwaukee, WI (United States); Larson, V. E. [Univ. of Wisconsin - Milwaukee, Milwaukee, WI (United States); Wang, M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)] (ORCID:000000029179228X); Rasch, P. J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-01-01

    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. 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.

  6. Radiative-convective instability

    E-Print Network [OSTI]

    Wing, Allison A.

    Radiative-moist-convective equilibrium (RCE) is a simple paradigm for the statistical equilibrium the earth's climate would exhibit in the absence of lateral energy transport. It has generally been assumed that for a given ...

  7. Unclassified Foreign Visits and Assignments

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

    1999-07-14

    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.

  8. Experiment to Characterize Tropical Cloud Systems

    SciTech Connect (OSTI)

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

    2005-08-02

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

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

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Comments? WeDatastreamstps DocumentationAtlanticENA

  10. 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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass mapSpeeding access| Department ofStephenSkinner,PastPatent80

  11. 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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass mapSpeedingProgramExemptions |(Conference)Project TourVehicles & Fuels »

  12. 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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverseIMPACTThousand CubicResourcelogo and-E C H2015Tray and| National

  13. Classified Visits Involving Foreign Nationals

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

    2004-01-13

    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.

  14. 2015 PLASTIC SURGERY VISITING PROFESSOR

    E-Print Network [OSTI]

    Shoubridge, Eric

    2015 PLASTIC SURGERY VISITING PROFESSOR Dr. MichaelW. Neumeister June 25th 2015 McGill University Division of Plastic Surgery #12;PROGRAM THURSDAY, JUNE 25th 2015 7:30 am OSLER AMPHITHEATRE ­ MONTREAL-102 Research Presentations ­ Residents & Graduate Students in Plastic Surgery 10:15 am Coffee Break 10:30 am

  15. Mikulski and Bolden Visit Goddard

    E-Print Network [OSTI]

    Christian, Eric

    . The recent completion of the critical design review for Webb and the delivery of all its instruments hardware in the Building 29 clean room. Photo credit: NASA/Goddard/Bill Hrybyk Reflecting on Webb Visits Goddard ­ 9 GCDC Science Fair Photo Gallery ­ 10 OutsideGoddard Audrey Haar ­ 12 On the cover

  16. 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

  17. 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

  18. 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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory ofDidDevelopmentat LENA|Upcoming

  19. The Tropical Warm Pool International Cloud Experiment

    SciTech Connect (OSTI)

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

    2008-05-01

    One of the most complete data sets describing tropical convection ever collected will result from the upcoming Tropical Warm Pool International Cloud Experiment (TWP-ICE) in the area around Darwin, Northern Australia in January and February 2006. The aims of the experiment, which will be operated in conjunction with the DOE Atmospheric Radiation Measurement (ARM) site in Darwin, will be to examine convective cloud systems from their initial stages through to the decay of the cirrus generated and to measure their impact on the environment. The experiment will include an unprecedented network of ground-based observations (soundings, active and passive remote sensors) combined with low, mid and high altitude aircraft for in-situ and remote sensing measurements. A crucial outcome of the experiment will be a data set suitable to provide the forcing and evaluation data required by cloud resolving and single column models as well as global climate models (GCMs) with the aim to contribute to parameterization development. This data set will provide the necessary link between the observed cloud properties and the models that are attempting to simulate them. The experiment is a large multi-agency experiment including substantial contributions from the United States DOE ARM program, ARM-UAV program, NASA, the Australian Bureau of Meteorology, CSIRO, EU programs and many universities.

  20. Can the vertical motions in the eyewall of tropical cyclones support persistent UAV flight?

    E-Print Network [OSTI]

    Poh, Chung-Kiak

    2014-01-01

    Powered flights in the form of manned or unmanned aerial vehicles (UAVs) have been flying into tropical cyclones to obtain vital atmospheric measurements with flight duration typically lasting between 12 and 36 hours. Convective vertical motion properties of tropical cyclones have previously been studied. This work investigates the possibility to achieve persistent flight by harnessing the generally pervasive updrafts in the eyewall of tropical cyclones. A sailplane UAV capable of vertical take-off and landing (VTOL) is proposed and its flight characteristics simulated. Results suggest that the concept of persistent flight within the eyewall is promising and may be extendable to the rainband regions.

  1. Visiting Faculty Program Program Description

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservationBio-Inspired SolarAbout /Two0 -UsingHeat & Cool History FusionVisit

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

    SciTech Connect (OSTI)

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

    2012-05-02

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

  3. Increased sensitivity of tropical cyclogenesis to wind shear in higher SST environments

    E-Print Network [OSTI]

    Nolan, David S.

    Increased sensitivity of tropical cyclogenesis to wind shear in higher SST environments David S in environments of radiative- convective equilibrium (RCE) generated by the same model. This method is extended to allow for the incorporation of mean wind shear into the RCE states, thus providing much more realistic

  4. Diurnal cycle of liquid water path over the subtropical and tropical oceans

    E-Print Network [OSTI]

    Hartmann, Dennis

    (Tropical Rainfall Measuring Mission Microwave Imager) satellite microwave radiometer data. Diurnal, consistent with a diurnal cycle driven largely by cloud solar absorption. In deep convective regions [1995] examined a two-point sampling of the LWP diurnal cycle of using the special sensor microwave

  5. Diurnal cycle of liquid water path over the subtropical and tropical oceans

    E-Print Network [OSTI]

    Wood, Robert

    (Tropical Rainfall Measuring Mission Microwave Imager) satellite microwave radiometer data. Diurnal, consistent with a diurnal cycle driven largely by cloud solar absorption. In deep convective regions], using a 17 day period of near-continuous ground based microwave radio- meter data around the time

  6. Climate and the Tropical Atlantic

    E-Print Network [OSTI]

    Climate and the Tropical Atlantic Presenter: Rick Lumpkin AOML Program Review 4-6 March 2014 What drives Tropical Atlantic climate changes and what are their impacts? #12;AOML Program Review2 Climate and the Tropical Atlantic Why this matters to NOAA and to society: Climate variability in the Tropical Atlantic

  7. 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

  8. Chaperone Information Self-guided Visit

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    's visit to the Seymour Center! Being a chaperone is a great way to experience the Seymour Center. When you arrive at the Seymour Center, help to assemble students at the yellow kiosk by the public entrance doors to wait respectfully. 3. Your group is participating in a Self-guided Visit of the Seymour

  9. Heat distribution by natural convection

    SciTech Connect (OSTI)

    Balcomb, J.D.

    1985-01-01

    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.

  10. Heat distribution by natural convection

    SciTech Connect (OSTI)

    Balcomb, J.D.; Yamaguchi, K.

    1983-01-01

    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.

  11. Spatially Modulated Structures in Convective Systems

    E-Print Network [OSTI]

    Kao, Hsien-Ching

    2013-01-01

    Mode in Pattern Formation Convection in a horizontal ?uid layer rotating about the vertical or subject

  12. Heat distribution by natural convection

    SciTech Connect (OSTI)

    Balcomb, J.D.

    1985-01-01

    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.

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

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

    Richmond's Kennedy High Visits NERSC Richmond's Kennedy High Visits NERSC Students Learn About Computing Careers February 10, 2011 Eighteen students from Richmond's Kennedy High...

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

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

    to Visit Georgia Nuclear Reactor Site and Tennessee Laboratory to Highlight Administration Support for Nuclear Energy Energy Secretary to Visit Georgia Nuclear Reactor Site and...

  15. President Obama Visits North Carolina's Cree, Inc., and Meets...

    Office of Environmental Management (EM)

    Visits North Carolina's Cree, Inc., and Meets with Council on Jobs and Competitiveness President Obama Visits North Carolina's Cree, Inc., and Meets with Council on Jobs and...

  16. Convective heat flow probe

    DOE Patents [OSTI]

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

    1984-01-09

    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.

  17. The predictability of consumer visitation patterns

    E-Print Network [OSTI]

    Llorente, Alejandro

    We consider hundreds of thousands of individual economic transactions to ask: how predictable are consumers in their merchant visitation patterns? Our results suggest that, in the long-run, much of our seemingly elective ...

  18. Urban Parks: Constraints on Park Visitation 

    E-Print Network [OSTI]

    Scott, David

    2006-12-19

    Research shows that women, older people, members of some ethnic groups, and people with low educational and income levels are less likely than others to participate in leisure activities or visit parks. This publication explores the constraints...

  19. FREE CONVECTIVE LAMINAR FLOW WITHIN THE TROMBE WALL CHANNEL

    E-Print Network [OSTI]

    Akbari, H.

    2011-01-01

    Foreign FREE CONVECTIVE LAMINAR FLOW WITHIN THE TROMBE WALLEnergy. -i- FREE CONVECTIVE LAMINAR FLOW WITHIN THE TROMBEABSTRACT Free convective laminar heat transfer between the

  20. LECTURES, EXCURSIONS, VISITS & ACTIVITIES FACULTY-LED GROUPS

    E-Print Network [OSTI]

    . Zinoladou) --Two-Day Excursion: Visits to traditional mountain villages in Macedonia (Escort: Admidis

  1. 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)

    2014-10-15

    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.

  2. Tracking tropical cloud systems for the diagnosis of simulations by the weather research and forecasting (WRF) model

    SciTech Connect (OSTI)

    Vogelmann, A.M.; Lin, W.; Cialella, A.; Luke, E. P.; Jensen, M. P.; Zhang, M. H.; Boer, E.

    2010-06-27

    To aid in improving model parameterizations of clouds and convection, we examine the capability of models, using explicit convection, to simulate the life cycle of tropical cloud systems in the tropical warm pool. The cloud life cycle is determined using a satellite cloud tracking algorithm (Boer and Ramanathan, J. Geophys. Res., 1997), and the statistics are compared to those of simulations using the Weather Research and Forecasting (WRF) Model. Using New York Blue, a Blue Gene/L supercomputer that is co-operated by Brookhaven and Stony Brook, simulations are run at a resolution comparable to the observations. Initial results suggest that the organization of the mesoscale convective systems is particularly sensitive to the cloud microphysics parameterization used.

  3. 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

    2004-05-30

    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.

  4. 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

  5. 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

    2012-01-19

    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.

  6. 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.

  7. 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

  8. The convective desalination of sea ice

    E-Print Network [OSTI]

    Rees Jones, David

    2014-07-01

    in the interstices of an ice matrix. My focus is on one of the processes by which the salt content of sea ice decreases, namely convective desalination, which is also often called gravity drainage by geophysicists. Modelling convective desalination requires...

  9. Q. J. R. Meteorol. Soc. (2004), 130, pp. 31193137 doi: 10.1256/qj.03.103 The simulation of the diurnal cycle of convective precipitation over land

    E-Print Network [OSTI]

    Chaboureau, Jean-Pierre

    2004-01-01

    Cloud Systems project, the problem of the simulation of the diurnal cycle of convective precipitation general- circulation model. The focus is on tropical South America and Africa where the diurnal cycle on surface temperature. It is primarily controlled by a change of vertical stability that arises as solar

  10. Visiting Graduate Program | Argonne National Laboratory

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservationBio-Inspired SolarAbout /Two0 -UsingHeat & Cool History FusionVisitVisiting

  11. Geography 102, Spring 2007 Tropical Climatology

    E-Print Network [OSTI]

    Office: Bunche Hall 1176 Phone: 206-4590/825-1071, email:raphael@geog.ucla.edu Office Hours: M/W 10:30p the development of Tropical Cli- mates - the laws that govern the movement of air; solar radiation in the Tropics in the Tropics - the Hadley Cells, the Trade Winds, the InterTropical Convergence Zone, the Tropical ocean

  12. 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

  13. NATURAL CONVECTION IN ROOM GEOMETRIES

    SciTech Connect (OSTI)

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

    1980-06-01

    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.

  14. Visit of the Federal President of Germany

    ScienceCinema (OSTI)

    None

    2011-04-25

    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.

  15. KV04: Baxter Mountain This route visits

    E-Print Network [OSTI]

    Reiter, Clifford A.

    11 KV04: Baxter Mountain General This route visits Baxter Mountain which is a short hike that has between Hurricane and Green Mountains. The hike is relatively short although there is a good elevation Description The trail begins on Rt9N directly across from Hurricane Mountain Road. From Keene Valley, go north

  16. 2003 Annual Report THE NIST VISITING COMMITTEE

    E-Print Network [OSTI]

    Manager Motorola ROBERTT.WILLIAMS Director, Manufacturing Operations Support & Technology Caterpillar Inc WAYNE H. PITCHER, JR. Technology Management Consultant DR. F. RAYMOND SALEMME Retired President2003 Annual Report THE NIST VISITING COMMITTEE ON ADVANCED TECHNOLOGY U.S. DEPARTMENT OF COMMERCE

  17. Spring 2005 Ag students visit Taiwan

    E-Print Network [OSTI]

    Maxwell, Bruce D.

    Spring 2005 Ag students visit Taiwan The following is a first-hand account of the "Follow the Grain" trip to Taiwan, written by Mary Anne Anderson, a senior in Ag Education from Big Timber. A jour- nal and international markets for grain, and the class culminates with a trip to facili- ties in Portland and Taiwan

  18. 2002 Annual Report THE NIST VISITING COMMITTEE

    E-Print Network [OSTI]

    . Technology Management Consultant DR. F. RAYMOND SALEMME President and Chief Scientific Officer 3-Dimensional2002 Annual Report THE NIST VISITING COMMITTEE ON ADVANCED TECHNOLOGY U.S. DEPARTMENT OF COMMERCE TECHNOLOGY ADMINISTRATION NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY JANUARY 2003 #12;Report prepared by

  19. An observational study of entrainment rate in deep convection

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

    Guo, Xiaohao; Lu, Chunsong; Zhao, Tianliang; Zhang, Guang Jun; Liu, Yangang

    2015-09-22

    This study estimates entrainment rate and investigates its relationships with cloud properties in 156 deep convective clouds based on in-situ aircraft observations during the TOGA-COARE (Tropical Ocean Global Atmosphere Coupled Ocean Atmosphere Response Experiment) field campaign over the western Pacific. To the authors’ knowledge, this is the first study on the probability density function of entrainment rate, the relationships between entrainment rate and cloud microphysics, and the effects of dry air sources on the calculated entrainment rate in deep convection from an observational perspective. Results show that the probability density function of entrainment rate can be well fitted by lognormal,more »gamma or Weibull distribution, with coefficients of determination being 0.82, 0.85 and 0.80, respectively. Entrainment tends to reduce temperature, water vapor content and moist static energy in cloud due to evaporative cooling and dilution. Inspection of the relationships between entrainment rate and microphysical properties reveals a negative correlation between volume-mean radius and entrainment rate, suggesting the potential dominance of homogeneous mechanism in the clouds examined. The entrainment rate and environmental water vapor content show similar tendencies of variation with the distance of the assumed environmental air to the cloud edges. Their variation tendencies are non-monotonic due to the relatively short distance between adjacent clouds.« less

  20. 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.

    2004-05-31

    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.

  1. Large-scale Environmental Variables and Transition to Deep Convection in Cloud Resolving Model Simulations: A Vector Representation

    SciTech Connect (OSTI)

    Hagos, Samson M.; Leung, Lai-Yung R.

    2012-11-01

    Cloud resolving model simulations and vector analysis are used to develop a quantitative method of assessing regional variations in the relationships between various large-scale environmental variables and the transition to deep convection. Results of the CRM simulations from three tropical regions are used to cluster environmental conditions under which transition to deep convection does and does not take place. Projections of the large-scale environmental variables on the difference between these two clusters are used to quantify the roles of these variables in the transition to deep convection. While the transition to deep convection is most sensitive to moisture and vertical velocity perturbations, the details of the profiles of the anomalies vary from region to region. In comparison, the transition to deep convection is found to be much less sensitive to temperature anomalies over all three regions. The vector formulation presented in this study represents a simple general framework for quantifying various aspects of how the transition to deep convection is sensitive to environmental conditions.

  2. Chinese Delegation Meets with EM Officials in its First Visit...

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

    Chinese Delegation Meets with EM Officials in its First Visit to Savannah River Site Chinese Delegation Meets with EM Officials in its First Visit to Savannah River Site November...

  3. Secretary Chu Visits Vogtle Nuclear Power Plant | Department...

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

    Secretary Chu Visits Vogtle Nuclear Power Plant Secretary Chu Visits Vogtle Nuclear Power Plant February 15, 2012 - 3:54pm Addthis Secretary Chu traveled to Waynesboro, Georgia, to...

  4. Energy Secretary Moniz Visits Clean Coal Facility in Mississippi...

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

    Energy Secretary Moniz Visits Clean Coal Facility in Mississippi Energy Secretary Moniz Visits Clean Coal Facility in Mississippi November 8, 2013 - 3:36pm Addthis On Friday, Nov....

  5. 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)

    1995-09-01

    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.

  6. Unclassified Foreign Visits and Assignments Program

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

    2004-06-18

    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

  7. Secretary Bodman Visits Iraq | 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 on Google Bookmark EERE: Alternative Fuels Data Center Home Page on DeliciousMathematicsEnergyInterestedReplacement-2-AA-1 SECTIONEnergy ScientistsinArabVisits Iraq Secretary

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

    E-Print Network [OSTI]

    Biwole, Pascal; Pompeo, C

    2013-01-01

    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...

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

    E-Print Network [OSTI]

    Hoofard, Michael Eugene

    1986-01-01

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

  10. The Role of Wave Energy Accumulation in Tropical Cyclogenesis over the Tropical North Atlantic

    E-Print Network [OSTI]

    Webster, Peter J.

    The Role of Wave Energy Accumulation in Tropical Cyclogenesis over the Tropical North Atlantic "wave energy"). Relative vorticity increases locally leading to an increase in the likelihood scales of interaction. The importance of wave energy accumulation for tropical cyclogenesis

  11. Visiting PPPL | Princeton Plasma Physics Lab

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory ofDidDevelopmentat LENA|UpcomingVisit Us Download the NIF PPPL Area Map

  12. Visiting Us | 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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory ofDidDevelopmentat LENA|UpcomingVisit Us Download the NIF PPPL AreaVisitor

  13. Visiting Us | Y-12 National Security Complex

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory ofDidDevelopmentat LENA|UpcomingVisit Us Download the NIF PPPL

  14. Sandia National Laboratories: Visiting Research Scholars

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust, High-ThroughputUpcoming Release of thePrograms:ModeRobotics:Robotics:SensorsVisiting

  15. Tropical bases by regular projections

    E-Print Network [OSTI]

    Hept, Kerstin

    2007-01-01

    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.

  16. Tracking tropical cloud systems - Observations for the diagnosis of simulations by the Weather Research and Forecasting (WRF) Model

    SciTech Connect (OSTI)

    Vogelmann, A.M.; Lin, W.; Cialella, A.; Luke, E.; Jensen, M.; Zhang, M.

    2010-03-15

    To aid in improving model parameterizations of clouds and convection, we examine the capability of models, using explicit convection, to simulate the life cycle of tropical cloud systems in the vicinity of the ARM Tropical Western Pacific sites. The cloud life cycle is determined using a satellite cloud tracking algorithm (Boer and Ramanathan, 1997), and the statistics are compared to those of simulations using the Weather Research and Forecasting (WRF) Model. Using New York Blue, a Blue Gene/L supercomputer that is co-operated by Brookhaven and Stony Brook, simulations are run at a resolution comparable to the observations. Initial results suggest a computational paradox where, even though the size of the simulated systems are about half of that observed, their longevities are still similar. The explanation for this seeming incongruity will be explored.

  17. Experimental study of internal wave generation by convection in water

    E-Print Network [OSTI]

    2015-01-01

    study of internal wave generation by convection in waterstudies of internal wave generation by convective turbulenceintermittent generation of internal waves. We also computed

  18. 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.

    2013-06-07

    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.

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

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

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

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

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

    will visit the Western Area Power Administration for a ceremony at the Electrical District No. 5 Substation to view progress on the Electrical District 5-to-Palo...

  1. Deputy Secretary Sherwood-Randall Visits Waste Isolation Pilot...

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

    Deputy Secretary of Energy, visited DOE's Waste Isolation Pilot Plant (WIPP) on Tuesday for a firsthand look at the progress in the recovery of operations at the...

  2. Convective heat transfer inside passive solar buildings

    SciTech Connect (OSTI)

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

    1983-11-01

    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.

  3. Convective heat transfer inside passive solar buildings

    SciTech Connect (OSTI)

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

    1983-01-01

    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. Transient Mixed Convection Validation for NGNP

    SciTech Connect (OSTI)

    Smith, Barton; Schultz, Richard

    2015-10-19

    The results of this project are best described by the papers and dissertations that resulted from the work. They are included in their entirety in this document. They are: (1) Jeff Harris PhD dissertation (focused mainly on forced convection); (2) Blake Lance PhD dissertation (focused mainly on mixed and transient convection). This dissertation is in multi-paper format and includes the article currently submitted and one to be submitted shortly; and, (3) JFE paper on CFD Validation Benchmark for Forced Convection.

  5. 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 ...

  6. Climate Theme Global Tropical Moored Buoy Array

    E-Print Network [OSTI]

    Climate Theme Global Tropical Moored Buoy Array: Observing, Understanding Observing System for Climate #12;Performance 4 Global Tropical Moored Buoy Array: A coordinated multi-national effort to develop and sustain moored buoy observing systems for climate research

  7. The multiple vortex nature of tropical cyclogenesis 

    E-Print Network [OSTI]

    Sippel, Jason Allen

    2005-02-17

    This thesis contains an observational analysis of the genesis of Tropical Storm Allison (2001). Using a paradigm of tropical cyclone formation as the superposition of potential vorticity (PV) anomalies, the importance of different scales of PV...

  8. 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 ...

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

    SciTech Connect (OSTI)

    Bennion, K.

    2014-06-01

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

  10. 8, 42214266, 2008 Tropical forest fire

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    ACPD 8, 4221­4266, 2008 Tropical forest fire emissions R. J. Yokelson et al. Title Page Abstract Chemistry and Physics Discussions The tropical forest and fire emissions experiment: laboratory fire Publications on behalf of the European Geosciences Union. 4221 #12;ACPD 8, 4221­4266, 2008 Tropical forest fire

  11. Geography 102, Spring 2006 Tropical Climatology

    E-Print Network [OSTI]

    Hours: Tu/Th 9:30p.m-10:30p.m., and by appointment Office: Bunche Hall 1176 Phone: 206 that underly the development of Tropical Cli- mates - the laws that govern the movement of air; solar radiation Circulation in the Tropics - the Hadley Cells, the Trade Winds, the InterTropical Convergence Zone

  12. Geography 102, Spring 2008 Tropical Climatology

    E-Print Network [OSTI]

    Hall 1176 Phone: 206-4590/825-1071, email:raphael@geog.ucla.edu Office Hours: M/W 10:00a.m-11:00a Cli- mates - the laws that govern the movement of air; solar radiation in the Tropics; temperature - the Hadley Cells, the Trade Winds, the InterTropical Convergence Zone, the Tropical ocean circulation

  13. Visiting Assistant Professor New Mexico Institute of Mining and Technology

    E-Print Network [OSTI]

    Borchers, Brian

    Visiting Assistant Professor New Mexico Institute of Mining and Technology The Department. Send all material to New Mexico Institute of Mining and Technology, Human Resources, Socorro, NM 87801 of Mathematics at New Mexico Institute of Mining and Tech- nology invites applications for a Visiting Assistant

  14. 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

  15. University of Maryland, Baltimore (UMB) Visiting Scientist Agreement

    E-Print Network [OSTI]

    Weber, David J.

    1 University of Maryland, Baltimore (UMB) Visiting Scientist Agreement Name of Visiting Scientist: In consideration of being permitted to perform research at the University of Maryland, Baltimore (UMB) and to use _______________________________________________ ________________ Signature Date AUTHORIZED OFFICIAL SIGNATURE FOR UNIVERSITY OF MARYLAND, BALTIMORE Signature Date *Signature

  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. 12-MONTH SAMPLE OFFER LETTER VISITING TEACHING FACULTY I, RESEARCH

    E-Print Network [OSTI]

    McQuade, D. Tyler

    12-MONTH SAMPLE OFFER LETTER VISITING TEACHING FACULTY I, RESEARCH FACULTY I, INSTRUCTIONAL SPECIALIST I OR ASSOCIATE IN RESEARCH APPOINTMENT Dear Dr. xxx: I am pleased to offer you a visiting://facultyhandbook.fsu.edu). This offer is also contingent upon your providing the necessary documents to prove your identity

  18. 9-MONTH SAMPLE OFFER LETTER VISITING TEACHING FACULTY I, RESEARCH

    E-Print Network [OSTI]

    McQuade, D. Tyler

    9-MONTH SAMPLE OFFER LETTER VISITING TEACHING FACULTY I, RESEARCH FACULTY I, INSTRUCTIONAL SPECIALIST I OR ASSOCIATE IN RESEARCH APPOINTMENT Dear Dr. xxx: I am pleased to offer you a visiting of interest, and intellectual property (http://facultyhandbook.fsu.edu). This offer is also contingent upon

  19. Policy on adverse weather conditions affecting Higher Education Review visits

    E-Print Network [OSTI]

    Neirotti, Juan Pablo

    Policy on adverse weather conditions affecting Higher Education Review visits This policy entered into owing to adverse weather conditions will be by mutual agreement of QAA and the provider. Attendance at the review visit by the QAA officer If adverse weather conditions prevent, or appear likely

  20. Vortex Tubes of Turbulent Solar Convection

    E-Print Network [OSTI]

    Kitiashvili, I N; Mansour, N N; Lele, S K; Wray, A A

    2011-01-01

    Investigation of turbulent properties of solar convection is extremely important for understanding of the multi-scale dynamics observed on the solar surface. In particular, recent high-resolution observations revealed ubiquitous vortical structures, and numerical simulations demonstrated links between the vortex tube dynamics and magnetic field organization, and also importance of vortex tube interactions in the mechanism of acoustic wave excitation on the Sun. In this paper we investigate mechanisms of formation of vortex tubes in highly-turbulent convective flows near the solar surface by using realistic radiative hydrodynamic LES simulations. Analysis of data, obtained by the simulations, indicates two basic processes of the vortex tube formation: 1) development of small-scale convective instability inside convective granules, and 2) a Kelvin-Helmholtz type instability of shearing flows in intergranular lanes. Our analysis shows that vortex stretching during these processes is a primary source of generatio...

  1. A modified convective/stratiform partitioning algorithm 

    E-Print Network [OSTI]

    Listemaa, Steven Alan

    1998-01-01

    by using different radar reflectivity-rail-ate relationships. Several authors have developed their own convective-stratiform partitioning, but each had its limitations. An algorithm has been developed which partitions precipitating systems...

  2. Circulation and convection in the Irminger Sea

    E-Print Network [OSTI]

    Våge, Kjetil

    2010-01-01

    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 ...

  3. Modeling convection in the Greenland Sea

    E-Print Network [OSTI]

    Bhushan, Vikas

    1998-01-01

    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 ...

  4. 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.

    2013-01-31

    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.

  5. Convective cores in galactic cooling flows

    E-Print Network [OSTI]

    A. Kritsuk; T. Plewa; E. Mueller

    2001-05-02

    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.

  6. Impact of a Revised Convective Triggering Mechanism on CAM2 Model Simulations: Results from Short-Range Weather Forecasts

    SciTech Connect (OSTI)

    Xie, S; Boyle, J S; Cederwall, R T; Potter, G L; Zhang, M; Lin, W

    2004-02-19

    This study implements a revised convective triggering condition in the National Center for Atmospheric Research (NCAR) Community Atmosphere Model (CAM2) model to reduce its excessive warm season daytime precipitation over land. The new triggering mechanism introduces a simple dynamic constraint on the initiation of convection that emulates the collective effects of lower level moistening and upward motion of the large-scale circulation. It requires a positive contribution from the large-scale advection of temperature and moisture to the existing positive Convective Available Potential Energy (CAPE) for model convection to start. In contrast, the original convection triggering function in CAM2 assumes that convection is triggered whenever there is positive CAPE, which results in too frequent warm season convection over land arising from strong diurnal variation of solar radiation. We examine the impact of the new trigger on CAM2 simulations by running the climate model in Numerical Weather Prediction (NWP) mode so that more available observations and high-frequency NWP analysis data can be used to evaluate model performance. We show that the modified triggering mechanism has led to considerable improvements in the simulation of precipitation, temperature, moisture, clouds, radiations, surface temperature, and surface sensible and latent heat fluxes when compared to the data collected from the Atmospheric Radiation Measurement (ARM) program at its South Great Plains (SGP) site. Similar improvements are also seen over other parts of the globe. In particular, the surface precipitation simulation has been significantly improved over both the continental United States and around the globe; the overestimation of high clouds in the equatorial tropics has been substantially reduced; and the temperature, moisture, and zonal wind are more realistically simulated. Results from this study also show that some systematic errors in the CAM2 climate simulations can be detected in the early stage of model integration. Examples are the extremely overestimated high clouds in the tropics in the vicinity of ITCZ and the spurious precipitation maximum in the east of the Rockies. This has important implications in studies of these model errors since running the climate model in NWP mode allows us to perform a more in-depth analysis during a short time period where more observations are available and different model errors from various processes have not compensated for the systematic errors.

  7. Homogeneous Ice Nucleation in Subtropical and Tropical Convection and Its Influence on Cirrus Anvil Microphysics

    E-Print Network [OSTI]

    and large aggregates. Thermodynamic analysis suggests that the air sampled in the updraft core was mixed- erogeneously or secondarily produced, or recycled). 1. Introduction The poorly understood processes of ice

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

    E-Print Network [OSTI]

    Masunaga, Hirohiko

    of a variety of satellite sensors including radars, an infrared and microwave sounder unit, and a microwave including air temperature, water vapor, cumulus cloud cover, and surface wind are composited with respect of moisture and dry static energy and their vertical flux at cloud base from satellite observations alone

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

    E-Print Network [OSTI]

    Zolman, Jody Lynn

    1999-01-01

    ). The number, size, and intensity of the MCSs were examined for differences between the years in eighteen different regions. There are well documented patterns of anomalous precipitation due to El Nino and La Nina, and in general the MCS distributions between...

  10. 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

  11. 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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverseIMPACT EVALUATION PLANIsProcessRegulationRadiative Transfer Model and

  12. M. Bahrami ENSC 388 (F09) Forced Convection Heat Transfer 1 Forced Convection Heat Transfer

    E-Print Network [OSTI]

    Bahrami, Majid

    surface, and the type of the fluid flow (laminar or turbulent). Fig. 1: Forced convection fluid. Whereas in forced convection, the fluid is forced to flow over a surface or in a tube Boundary Layer Consider the flow of a fluid over a flat plate, the velocity and the temperature

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

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

    Assistant Secretary for Oil and Natural Gas Paula Gant visits GE O&G Customer Collaboration Center in Houston. (L to R - Chrissy Borskey, GE Distributed Power; Tracey Sledge, GE...

  14. VisIt at NERSC - 3D Scientific Visualization

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

    of creating new plugins. VisIt provides an easy-to-use GUI as well as C++, Python and Java interfaces. The Python scripting interface gives users the ability to batch process...

  15. Lempke visits Savannah River Site | National Nuclear Security...

    National Nuclear Security Administration (NNSA)

    Lempke visits Savannah River Site May 29, 2013 at 11:00 am Blog archive October 2015 (8) September 2015 (9) August 2015 (10) July 2015 (8) June 2015 (6) May 2015 (18) April...

  16. The tropical double description method

    E-Print Network [OSTI]

    Allamigeon, Xavier; Goubault, Eric

    2010-01-01

    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.

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

    SciTech Connect (OSTI)

    Mariner, Paul E.; Hardin, Ernest L.; Miksova, Jitka

    2013-02-01

    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.

  18. Low enthalpy convective system in Western Ohio

    SciTech Connect (OSTI)

    Cannon, M.S.; Tabet, C.A.; Eckstein, Y.

    1980-01-01

    A distinct positive anomaly in the temperatures of the shallow (Pleistocene) aquifers along the Cincinnati-Findlay Arch in Western Ohio coincides with a low geothermal gradient. A conceptual model of convective currents associated with a tensional fault and/or fracture system along the crest of the Arch is suggested as an explanation of the anomaly. Hydrochemical information indicates that various quantities of warmer ground water, with the composition characteristics of deep bedrock aquifers, is present as an admixture in the shallow aquifers. This confirms the conceptual model of convection in fractures.

  19. Laser induced ponderomotive convection in water

    E-Print Network [OSTI]

    Shneider, M N

    2015-01-01

    A new mechanism for inducing convection during IR laser interaction with water or any absorbing polar liquid is described theoretically. The numerical simulations performed using the developed model show that the ponderomotive force produces water flow in the direction of the laser beam propagation. In the later stage of interaction, when water temperature rises, the Archimedes force becomes first comparable and then dominant producing convection directed against the vector of gravitational acceleration (upward). The theoretical estimates and the numerical simulations predict fluid dynamics that is similar to the observed in the previous experiments.

  20. Geothermal reservoirs in hydrothermal convection systems

    SciTech Connect (OSTI)

    Sorey, M.L.

    1982-01-01

    Geothermal reservoirs commonly exist in hydrothermal convection systems involving fluid circulation downward in areas of recharge and upwards in areas of discharge. Because such reservoirs are not isolated from their surroundings, the nature of thermal and hydrologic connections with the rest of the system may have significant effects on the natural state of the reservoir and on its response to development. Conditions observed at numerous developed and undeveloped geothermal fields are discussed with respect to a basic model of the discharge portion of an active hydrothermal convection system. Effects of reservoir development on surficial discharge of thermal fluid are also delineated.

  1. Thermal convection in a liquid metal battery

    E-Print Network [OSTI]

    Shen, Yuxin

    2015-01-01

    Generation of thermal convection flow in the liquid metal battery, a device recently proposed as a promising solution for the problem of the short-term energy storage, is analyzed using a numerical model. It is found that convection caused by Joule heating of electrolyte during charging or discharging is virtually unavoidable. It exists in laboratory prototypes larger than a few cm in size and should become much stronger in larger-scale batteries. The phenomenon needs further investigation in view of its positive (enhanced mixing of reactants) and negative (loss of efficiency and possible disruption of operation due to the flow-induced deformation of the electrolyte layer) effects.

  2. Generation and Trapping of Gravity Waves from Convection with Comparison to Parameterization

    E-Print Network [OSTI]

    Alexander, M. Joan

    Generation and Trapping of Gravity Waves from Convection with Comparison to Parameterization M (GCMs) add realism by describing wave generation by tropospheric convection. Because the convection in GCMs is itself a parameterized process, these convectively generated wave parameterizations necessarily

  3. Numerical models of Rayleigh-Taylor instabilities superimposed upon convection

    E-Print Network [OSTI]

    Schmeling, Harro

    one R.T.-overturn to multiple convective with salt tectonics (R.T.), plutonism (R.T.), plate overturns. Secondly, how is the temperature field tectonics and mantle flows (convection) (see e.g. affected

  4. On the Forecasting of Orogenic Mesoscale Convective Complexes

    E-Print Network [OSTI]

    Tucker, Donna F.; Zentmire, Kristine S.

    1999-12-01

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

  5. The Role of the Tropics in Abrupt Climate Changes

    SciTech Connect (OSTI)

    Fedorov, Alexey

    2013-12-07

    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.

  6. Deep convective parameterization: Some issues (and some solutions?)

    E-Print Network [OSTI]

    Plant, Robert

    are basically an exercise in engineering / tuning fairly bad Deep convective parameterization ­ p.1/4 #12;Aim in engineering / tuning fairly bad The reality is that deep convective parameterizations are basicallyDeep convective parameterization: Some issues (and some solutions?) Bob Plant Department

  7. Convection in Stars Proceedings IAU Symposium No. 239, 2007

    E-Print Network [OSTI]

    Arnett, W. David

    and the geometric parameters in mixing length theory, and the solar Ne abundance problem. Explicit comparisons convection (with nuclear burning). The simulations are run long enough so that a robust statistical state will be made with convective driving of waves, convective zone growth by entrainment, the velocity scale

  8. Convective injection into stratospheric intrusions Cameron R. Homeyer,1

    E-Print Network [OSTI]

    Pan, Laura

    Convective injection into stratospheric intrusions Cameron R. Homeyer,1 Kenneth P. Bowman,1 Laura L, are not entirely understood. This study presents direct observations of moist convection penetrating into stratospheric intrusions. The characteristics of convective injection are shown by using in situ aircraft

  9. Stellar convective cores as dark matter probes

    E-Print Network [OSTI]

    Jordi Casanellas; Isa M. Brandão; Yveline Lebreton

    2015-05-06

    The recent detection of a convective core in a main-sequence solar-type star is used here to test particular models of dark matter (DM) particles, those with masses and scattering cross sections in the range of interest for the DM interpretation of the positive results in several DM direct detection experiments. If DM particles do not effectively self-annihilate after accumulating inside low-mass stars (e.g. in the asymmetric DM scenario) their conduction provides an efficient mechanism of energy transport in the stellar core. For main-sequence stars with masses between 1.1 and 1.3 Msun, this mechanism may lead to the suppression of the inner convective region expected to be present in standard stellar evolution theory. The asteroseismic analysis of the acoustic oscillations of a star can prove the presence/absence of such a convective core, as it was demonstrated for the first time with the Kepler field main-sequence solar-like pulsator, KIC 2009505. Studying this star we found that the asymmetric DM interpretation of the results in the CoGeNT experiment is incompatible with the confirmed presence of a small convective core in KIC 2009505.

  10. Laminar boundary layers in convective heat transport

    E-Print Network [OSTI]

    Christian Seis

    2012-12-12

    We study Rayleigh-Benard convection in the high-Rayleigh-number and high-Prandtl-number regime, i.e., we consider a fluid in a container that is exposed to strong heating of the bottom and cooling of the top plate in the absence of inertia effects. While the dynamics in the bulk are characterized by a chaotic convective heat flow, the boundary layers at the horizontal container plates are essentially conducting and thus the fluid is motionless. Consequently, the average temperature exhibits a linear profile in the boundary layers. In this article, we rigorously investigate the average temperature and oscillations in the boundary layer via local bounds on the temperature field. Moreover, we deduce that the temperature profile is indeed essentially linear close to the horizontal container plates. Our results are uniform in the system parameters (e.g. the Rayleigh number) up to logarithmic correction terms. An important tool in our analysis is a new Hardy-type estimate for the convecting velocity field, which can be used to control the fluid motion in the layer. The bounds on the temperature field are derived with the help of local maximal regularity estimates for convection-diffusion equations.

  11. Benefits of Tropical Forest Management Under the New Climate...

    Open Energy Info (EERE)

    Benefits of Tropical Forest Management Under the New Climate Change Agreement-A Case Study in Cambodia Jump to: navigation, search Name Benefits of Tropical Forest Management Under...

  12. 7, 69036958, 2007 Tropical Forest fire

    E-Print Network [OSTI]

    Boyer, Edmond

    ACPD 7, 6903­6958, 2007 Tropical Forest fire emissions R. J. Yokelson et al. Title Page Abstract Discussions The Tropical Forest and fire emissions experiment: overview and airborne fire emission factor Forest Service, Fire Sciences Laboratory, Missoula, MT, USA Received: 4 May 2007 ­ Accepted: 10 May 2007

  13. Penetrative internally heated convection in two and three dimensions

    E-Print Network [OSTI]

    Goluskin, David

    2015-01-01

    Convection of an internally heated fluid, confined between top and bottom plates of equal temperature, is studied by direct numerical simulation in two and three dimensions. The unstably stratified upper region drives convection that penetrates into the stably stratified lower region. The fraction of produced heat escaping across the bottom plate, which is one half without convection, initially decreases as convection strengthens. Entering the turbulent regime, this decrease reverses in two dimensions but continues monotonically in three dimensions. The mean fluid temperature, which grows proportionally to the heating rate ($H$) without convection, grows like $H^{4/5}$ when convection is strong in both two and three dimensions. The ratio of the heating rate to the fluid temperature is likened to the Nusselt number of Rayleigh-B\\'enard convection. Simulations are reported for Prandtl numbers between 0.1 and 10 and for Rayleigh numbers (defined in terms of the heating rate) up to $5\\times10^{10}$.

  14. The Phenix ultimate natural convection test

    SciTech Connect (OSTI)

    Gauthe, P.; Pialla, D.; Tenchine, D.; Vasile, A.; Rochwerger, D.

    2012-07-01

    The French sodium cooled fast reactor Phenix was shut down in 2009 after 35 years of operation. Before decommissioning, a final set of tests were performed by the CEA during 9 months. Several topics were involved such as thermal hydraulics, core physics and fuel behaviour. Among these ultimate experiments, two thermal hydraulic tests were performed: an asymmetrical test consisting in a trip of one secondary pump and a natural convection test in the primary circuit. Recognizing the unique opportunity offered by these Phenix ultimate tests, IAEA decided in 2007 to launch a Coordinated Research Project (CRP) devoted to benchmarking analyses with system codes on the Phenix natural convection test. One objective of the natural convection test in Phenix reactor is the assessment of the CATHARE system code for safety studies on future and advanced sodium cooled fast reactors. The aim of this paper is to describe this test, which was performed on June 22-23, 2009, and the associated benchmark specifications for the CRP work. The paper reminds briefly the Phenix reactor with the main physical parameters and the instrumentation used during the natural convection test. After that, the test scenario is described: - initial state at a power of 120 MWth, - test beginning resulting from a manual dry out of the two steam generators, - manual scram, - manual trip on the three primary pumps without back-up by pony motors, - setting and development of natural convection in the primary circuit, in a first phase without significant heat sink in the secondary circuits and in a second phase with significant heat sink in the secondary circuits, by opening the casing of steam generators to create an efficient heat sink, by air natural circulation in the steam generators casing. The benchmark case ends after this second phase, which corresponds to the experimental test duration of nearly 7 hours. The paper presents also the benchmark specifications data supplied by the CEA to all participants of this CRP in order to perform calculations (core, primary circuit, primary pumps, IHX, shutdown system, operating parameters, test scenario and real test conditions). Finally, main test results and analyses are presented including the evolution of the core and of the heat exchangers inlet and outlet temperatures, and some local temperature measurements. The natural convection has been easily set up in the pool type reactor Phenix with different boundary conditions at the secondary side, with or without heat sink. The data obtained during this unique test represent some very useful and precious results for the development of SFR in a wide range of thematic such as numerical methods dedicated to thermal-hydraulics safety analyses (system codes, CFD codes and coupling system and CFD codes) and instrumentation. (authors)

  15. Visiting Faculty Program (VFP) | Princeton Plasma Physics Lab

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservationBio-Inspired SolarAbout /Two0 -UsingHeat & Cool History FusionVisit theVisiting

  16. Convection of a stratified colloidal suspension

    SciTech Connect (OSTI)

    Cherepanov, I. N.; Smorodin, B. L., E-mail: bsmorodin@yandex.ru [Perm National Research University (Russian Federation)

    2013-11-15

    The convection of a colloidal suspension, which is a binary mixture of a carrier medium with an admixture of nanoparticles having a large positive thermal diffusion parameter, has been studied for the case of the heating of a horizontal cell from below and periodic conditions at the vertical boundaries corresponding to the experimental situation of ring channels. Bifurcation diagrams have been constructed for vibrational and monotonic regimes of the convection of the colloidal mixture. The time dependences of the maximum stream function and the stream function at a fixed point of the cell, as well as the spatial distributions of the concentration field of the colloid admixture, have been obtained. It has been shown that a stable regime of traveling waves exists in a certain region of the parameters of the problem (Boltzmann and Rayleigh numbers characterizing the gravitational stratification and intensity of the thermal effect, respectively)

  17. Laminar boundary layers in convective heat transport

    E-Print Network [OSTI]

    Seis, Christian

    2012-01-01

    We study Rayleigh-Benard convection in the high-Rayleigh-number and high-Prandtl-number regime, i.e., we consider a fluid in a container that is exposed to strong heating of the bottom and cooling of the top plate in the absence of inertia effects. While the dynamics in the bulk are characterized by a chaotic convective heat flow, the boundary layers at the horizontal container plates are essentially conducting and thus the fluid is motionless. Consequently, the average temperature exhibits a linear profile in the boundary layers. In this article, we rigorously investigate the average temperature and oscillations in the boundary layer via local bounds on the temperature field. Moreover, we deduce that the temperature profile is indeed essentially linear close to the horizontal container plates. Our results are uniform in the system parameters (e.g. the Rayleigh number) up to logarithmic correction terms. An important tool in our analysis is a new Hardy-type estimate for the convecting velocity field, which ca...

  18. Convective heat transport in geothermal systems

    SciTech Connect (OSTI)

    Lippmann, M.J.; Bodvarsson, G.S.

    1986-08-01

    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.

  19. Magnetic flux concentrations from turbulent stratified convection

    E-Print Network [OSTI]

    Käpylä, P J; Kleeorin, N; Käpylä, M J; Rogachevskii, I

    2015-01-01

    (abridged) Context: The mechanisms that cause the formation of sunspots are still unclear. Aims: We study the self-organisation of initially uniform sub-equipartition magnetic fields by highly stratified turbulent convection. Methods: We perform simulations of magnetoconvection in Cartesian domains that are $8.5$-$24$ Mm deep and $34$-$96$ Mm wide. We impose either a vertical or a horizontal uniform magnetic field in a convection-driven turbulent flow. Results: We find that super-equipartition magnetic flux concentrations are formed near the surface with domain depths of $12.5$ and $24$ Mm. The size of the concentrations increases as the box size increases and the largest structures ($20$ Mm horizontally) are obtained in the 24 Mm deep models. The field strength in the concentrations is in the range of $3$-$5$ kG. The concentrations grow approximately linearly in time. The effective magnetic pressure measured in the simulations is positive near the surface and negative in the bulk of the convection zone. Its ...

  20. Convective Dynamo Simulation with a Grand Minimum

    E-Print Network [OSTI]

    Augustson, Kyle; Miesch, Mark; Toomre, Juri

    2015-01-01

    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...

  1. Contemporary Mathematics Quantum chaos: a brief rst visit

    E-Print Network [OSTI]

    Contemporary Mathematics Quantum chaos: a brief #28;rst visit Stephan De Bièvre Abstract to some aspects of quantum chaos that is adapted #21; it is hoped #21; to the audience of the school of the Schnirelman theorem is given in this context. 1. Introduction Quantum chaos, or quantum chaology, as Michael

  2. New York City Visiting or living in New York

    E-Print Network [OSTI]

    Navigating New York City #12;·Visiting or living in New York for the first time is an interesting. #12;Learn the geography of New York City's five boroughs. 1) Manhattan 2) Brooklyn 3) Queens 4) Bronx Major airports serving New York City: 1) John F. Kennedy International Airport (JFK) 2) La

  3. Engineering by Design For more information, visit our website

    E-Print Network [OSTI]

    Virginia Tech

    Engineering by Design For more information, visit our website at http://www.aoe.vt.edu or call 540 in the aerospace and related industries and in the shipbuilding, naval engineering, and ship design fields. Some also choose to go into related fields such as automotive engineering, structural engineering

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

    SciTech Connect (OSTI)

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

    1994-11-01

    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.

  5. SPORTS HANDBOOK Visit us at: www.recwell.umn.edu

    E-Print Network [OSTI]

    Minnesota, University of

    1 INTRAMURAL SPORTS HANDBOOK Visit us at: www.recwell.umn.edu Revised: 5/2014 ATTENTION TEAM are prepared to accept the commitment and duties inherent in the title you are assuming. This handbook has been read this guide carefully and keep it available at all times. After reading this handbook, if you feel

  6. 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

  7. For more information visit: www.informaworld.com/IJRS

    E-Print Network [OSTI]

    Wang, Le

    and spatial analytical technologies Guest editors contact information Dr. Le Wang Assistant ProfessorFor more information visit: www.informaworld.com/IJRS Call for Papers International Journal of Remote Sensing Special Issue on "Population Estimation Using Remote Sensing and GIS Technologies" Guest

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

    E-Print Network [OSTI]

    Abidi, Syed Sibte Raza

    Re-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 and practice of healthcare · Health Informatics is the study of applying information and technology to improve

  9. Akademisches Auslandsamt / International Office Check list for International Visiting Scholars

    E-Print Network [OSTI]

    Steinhoff, Heinz-Jürgen

    with an insurance company before entering Germany to ensure that any problems can be clarified in good time for yourself and any family members accompanying you, you are frequently required to submit the originals your applications together with those for their family members. Visiting scholars should bear in mind

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

    SciTech Connect (OSTI)

    Lackmann, Gary

    2013-06-10

    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.

  11. 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

    2014-12-27

    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.

  12. Effects of convection on the mean solar structure

    E-Print Network [OSTI]

    Christensen-Dalsgaard, J

    1996-01-01

    The overall framework for the study of solar convection and oscillations is the spherically symmetric component of solar structure. I discuss those properties of the solar interior which depend on convection and other possible hydrodynamical motion and the increasingly detailed information about the structure which is provided by helioseismic data. The most basic dependence of solar models on convection is the calibration to fix the solar radius. The dominant causes for differences in oscillation frequencies between the Sun and solar models seem to be located near the top of the convection zone. However, there is also evidence for possible weak mixing below the convection zone and perhaps in the solar core. The former, at least, might be induced by penetration of convective motion into the stable layers below.

  13. Soil Moisture Impacts on Convective Precipitation in Oklahoma 

    E-Print Network [OSTI]

    Ford, Trenton

    2015-07-24

    of the States” instilled in me a lifelong curiosity in Geography. v NOMENCLATURE CAPE Convective Available Potential Energy CIN Convective Inhibition CTP Convective Triggering Potential DDR Directional Difference Ratio DM Dry Moderate DP Dry Polar.... The black line represents the 1-to-1 fit, while the dashed line represents the least squares fit. .………………………..119 Figure 5.3. Boxplots of DDR from each directional difference over dry soil events. The black, dashed line represents the 0 value, by which...

  14. The Tropical Forest and Fire Emissions Experiment: overview and airborne fire emission factor measurements

    E-Print Network [OSTI]

    2007-01-01

    W. M. : The tropical forest and fire emissions experiment:Physics The Tropical Forest and Fire Emissions Experiment:A. : The tropical forest and fire emissions experiment:

  15. Interactions between cumulus convection and its environment as...

    Office of Scientific and Technical Information (OSTI)

    Convective Clouds Experiment (MC3E) in central Oklahoma. Distinct large-scale structures and diabatic heating and drying profiles are presented for cases of weaker and...

  16. Objectives of Work Packages WP1: Thermal convection

    E-Print Network [OSTI]

    Cerveny, Vlastislav

    MAGMA Objectives of Work Packages WP1: Thermal convection Coordinator: O. Cadek · To enhance air-pollution assessment in the urban environment · To study the solar radiation impact

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

    E-Print Network [OSTI]

    Gadgil, Ashok; Bauman, Fred; Kammerud, Ronald

    2008-01-01

    CONVECTION IN PASSIVE SOLAR BUILDINGS: ANALYSIS AND RESULTSCONVECTION IN PASSIVE SOLAR BUILDINGS: EXPERIMENTS, ANALYSISin a direct gain passive solar building; this is described

  18. Convectively generated zonal jets by thunderstorms on Jupiter

    E-Print Network [OSTI]

    Zhang, Xi Arthur; Showman, Adam

    2011-01-01

    formation of equatorial jets in freely decaying shallowof moist convection with zonal jets on Jupiter and Saturn,Generation of equatorial jets by large-scale latent heating

  19. Tianxing Cai, Visiting Assistant Professor Dan F. Smith Department of Chemical Engineering

    E-Print Network [OSTI]

    Guo, John Zhanhu

    Tianxing Cai, Visiting Assistant Professor Dan F. Smith Department of Chemical Engineering Lamar, Texas Chemical Engineering Ph.D., 2014 B. Professional Experience 2015 ­ Present Visiting Assistant., "Coupling Multiple Water-reuse Network Designs for Agile Manufacturing", Computers & Chemical Engineering

  20. 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...

  1. UK Nuclear Cleanup and Research Experts Visit DOE to Expand Collaborat...

    Office of Environmental Management (EM)

    UK Nuclear Cleanup and Research Experts Visit DOE to Expand Collaboration UK Nuclear Cleanup and Research Experts Visit DOE to Expand Collaboration September 30, 2014 - 12:00pm...

  2. 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

    2013-11-15

    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.

  3. Natural convection airflow measurement and theory

    SciTech Connect (OSTI)

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

    1984-01-01

    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.

  4. Atmospheric Radiation Measurement Convective and Orographically Induced

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 OutreachProductswsicloudwsiclouddenDVA N C E D B L O O DBiomass and BiofuelsPhysicist47 Industrial1Convective and

  5. ARM - Evaluation Product - Convective Vertical Velocity

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Comments? WeDatastreamstps DocumentationAtlanticENA Contacts ENA RelatedProductsCalibrated KAZRProductsConvective

  6. 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.

    2014-05-28

    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.

  7. Vermont Wilderness Observation Assignment You are to visit one of the legally designated Wilderness areas in Vermont. The duration

    E-Print Network [OSTI]

    Brown, Gregory G.

    Vermont Wilderness Observation Assignment You are to visit one of the legally designated Wilderness areas in Vermont. The duration of your visit is up to you. The purpose of your visit is to conduct

  8. Paying a Visit: The Dalai Lama Effect on International Trade

    E-Print Network [OSTI]

    Fuchs, Andreas; Klann, Nils-Hendrik

    2011-01-26

    be negatively affected by a planned meeting between Dutch members of parliament and the Dalai Lama (“’We are clear: no dalai lama visits”, NRC Handelsblad, May 7th 2009, available at: http://www.nrc.nl/international/Features/article2234645.ece... ” which France alone would have to bear.21 In early 2009, France was crossed off the travel agenda of two Chinese trade delegations. The first delegation alone signed 15 billion US dollars’ worth of trade deals in other European countries. Furthermore...

  9. 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 2012 Annual Report Visiting Committee on Advanced Technology of the National Institute of Standards and Technology U.S. Department of Commerce February 2013 #12;VISITING COMMITTEE ON ADVANCED TECHNOLOGY National

  10. 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 2008 Annual Report Visiting Committee on Advanced Technology of the National Institute of Standards and Technology U.S. Department of Commerce February 24, 2009 #12;VISITING COMMITTEE ON ADVANCED

  11. 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

  12. 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

  13. 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

  14. Air convection noise of pencil-beam interferometer for long trace profiler

    E-Print Network [OSTI]

    Yashchuk, Valeriy V.; Irick, Steve C.; MacDowell, Alastair A.; McKinney, Wayne R.; Takacs, Peter Z.

    2006-01-01

    Air Convection Noise of Pencil-beam Interferometer for Longwe investigate the effect of air convection on laser-beamshown that the NPD spectra due to air convection have a very

  15. 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

  16. Tuberous legumes: preliminary evaluation of tropical Australian and introduced species as fuel crops

    SciTech Connect (OSTI)

    Saxon, E.C.

    1981-04-01

    The evaluation of native and introduced legumes with starch-storing roots or tubers was undertaken to test whether plants traditionally collected as food by Australian aborigines might have a role in the development of crops for liquid fuel production (by fermentation of carbohydrates to ethanol). Tuberous-rooted legumes from overseas were planted at the Commonwealth Scientific and Industrial Research Organization, division of Tropical Crops and Pastures, Kimberley Research Station, Western Australia (15/sup 0/39'S, 128/sup 0/42'E) in December 1974, March 1978 and February 1979. Roots from the latter plantings were harvested in June 1979. Native plant material was collected during visits to aboriginal communities in the Kimberleys between April and June 1979. The native and introduced specimens were analyzed for fermentable carbohydrate and protein content. Several native plants appear more promising than introduced species as liquid fuel crops.

  17. CONVECTIVE STABILITY OF GALAXY-CLUSTER PLASMAS Benjamin D. Chandran

    E-Print Network [OSTI]

    Chandran, Ben

    criterion by causing heat to diffuse primarily along magnetic field lines. We extend earlier analyses a cluster's age. In the cooling flow model, plasma heating is neglected, and the rate at which plasma cools nuclei and cosmic rays drive convection in galaxy-cluster plasmas and that convection heats cluster cores

  18. 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

  19. Toward the Long-range Prediction of Severe Convective Windstorms

    E-Print Network [OSTI]

    Kuligowski, Bob

    Toward the Long-range Prediction of Severe Convective Windstorms Ken Pryor Department review pertaining to severe convective windstorm (SCW) structure and evolution. · Identify potential for the development of a long-range SCW prediction technique. #12;Background · Severe windstorms resulting from large

  20. ON THE INTERACTION BETWEEN CONVECTION AND MAGNETIC FIELDS Fausto Cattaneo

    E-Print Network [OSTI]

    Emonet, Thierry

    found in these different regimes are described and analyzed. Subject headings: convection -- Sun: magnetic fields -- Sun: photosphere 1. INTRODUCTION Magnetic activity is exhibited by late-type stars with deep convective envelopes, but the fine structure of the magnetic field can only be detected on the Sun

  1. Accepted Manuscript Simulations of stellar convection with CO5BOLD

    E-Print Network [OSTI]

    Wedemeyer-Böhm, Sven

    ­ the top of the deep-reaching solar convection zone. Convection plays a role for the thermal structure of the solar interior and the dynamo acting there, for the stratification of the photosphere, where most stratification leads to completely dif- ferent conditions in the interior, the photosphere, and the corona

  2. Characterizing the convective velocity fields in massive stars

    SciTech Connect (OSTI)

    Chatzopoulos, Emmanouil; Graziani, Carlo; Couch, Sean M., E-mail: manolis@astro.as.utexas.edu [Department of Astronomy and Astrophysics, Flash Center for Computational Science, University of Chicago, Chicago, IL 60637 (United States)

    2014-11-01

    We apply the mathematical formalism of vector spherical harmonics decomposition to convective stellar velocity fields from multidimensional hydrodynamics simulations and show that the resulting power spectra furnish a robust and stable statistical description of stellar convective turbulence. Analysis of the power spectra helps identify key physical parameters of the convective process such as the dominant scale of the turbulent motions that influence the structure of massive evolved pre-supernova stars. We introduce the numerical method that can be used to calculate vector spherical harmonics power spectra from two-dimensional (2D) and three-dimensional (3D) convective shell simulation data. Using this method we study the properties of oxygen shell burning and convection for a 15 M {sub ?} star simulated by the hydrodynamics code FLASH in 2D and 3D. We discuss the importance of realistic initial conditions to achieving successful core-collapse supernova explosions in multidimensional simulations. We show that the calculated power spectra can be used to generate realizations of the velocity fields of presupernova convective shells. We find that the slope of the solenoidal mode power spectrum remains mostly constant throughout the evolution of convection in the oxygen shell in both 2D and 3D simulations. We also find that the characteristic radial scales of the convective elements are smaller in 3D than in 2D, while the angular scales are larger in 3D.

  3. Plains Elevated Convection at Night (PECAN) Experiment Science Plan

    SciTech Connect (OSTI)

    Turner, D; Parsons, D; Geerts, B

    2015-03-01

    The Plains Elevated Convection at Night (PECAN) experiment is a large field campaign that is being supported by the National Science Foundation (NSF) with contributions from the National Oceanic and Atmospheric Administration (NOAA), the National Atmospheric and Space Administration (NASA), and the U.S. Department of Energy (DOE). The overarching goal of the PECAN experiment is to improve the understanding and simulation of the processes that initiate and maintain convection and convective precipitation at night over the central portion of the Great Plains region of the United States (Parsons et al. 2013). These goals are important because (1) a large fraction of the yearly precipitation in the Great Plains comes from nocturnal convection, (2) nocturnal convection in the Great Plains is most often decoupled from the ground and, thus, is forced by other phenomena aloft (e.g., propagating bores, frontal boundaries, low-level jets [LLJ], etc.), (3) there is a relative lack of understanding how these disturbances initiate and maintain nocturnal convection, and (4) this lack of understanding greatly hampers the ability of numerical weather and climate models to simulate nocturnal convection well. This leads to significant uncertainties in predicting the onset, location, frequency, and intensity of convective cloud systems and associated weather hazards over the Great Plains.

  4. Influences of soil moisture and vegetation on convective precipitation forecasts

    E-Print Network [OSTI]

    Robock, Alan

    Influences of soil moisture and vegetation on convective precipitation forecasts over the United and vegetation on 30 h convective precipitation forecasts using the Weather Research and Forecasting model over, the complete removal of vegetation produced substantially less precipitation, while conversion to forest led

  5. Precipitation distributions for explicit versus parameterized convection in a

    E-Print Network [OSTI]

    Wirosoetisno, Djoko

    Precipitation distributions for explicit versus parameterized convection in a large-domain high.J. and Lister, G.M.S. (2012) Precipitation distributions for explicit versus parameterized convection in a large. Meteorol. Soc. 138: 1692­1708, October 2012 A Precipitation distributions for explicit versus parametrized

  6. Magnetic fields in non-convective regions of stars

    E-Print Network [OSTI]

    Braithwaite, J

    2015-01-01

    We review the current state of knowledge of magnetic fields inside stars, concentrating on recent developments concerning magnetic fields in stably stratified (zones of) stars, leaving out convective dynamo theories and observations of convective envelopes. We include the observational properties of A, B and O-type main-sequence stars, which have radiative envelopes, and the fossil field model which is normally invoked to explain the strong fields sometimes seen in these stars. Observations seem to show that Ap-type stable fields are excluded in stars with convective envelopes. Most stars contain both radiative and convective zones, and there are potentially important effects arising from the interaction of magnetic fields at the boundaries between them, the solar cycle being one of the better known examples. Related to this, we discuss whether the Sun could harbour a magnetic field in its core. Recent developments regarding the various convective and radiative layers near the surfaces of early-type stars and...

  7. Tropical cyclone preparedness and response : opportunities for operations research

    E-Print Network [OSTI]

    Murphy, Maurice D

    2008-01-01

    This thesis explores how operations research methods can be applied in the emergency response community by looking at two recent tropical storm disasters; tropical cyclone Yemyin in Pakistan, June 2007 and super typhoon ...

  8. Channel planform dynamics of an alluvial tropical river 

    E-Print Network [OSTI]

    Alvarez, Aldo

    2005-08-29

    apparently plays a relatively minor role as a formative event in shaping the overall humid tropical landscape. A third objective was to develop an empirical model for predicting bend migration rates in humid tropical rivers, resulting in empirical...

  9. The Precipitation Characteristics of ISCCP Tropical Weather States DONGMIN LEE

    E-Print Network [OSTI]

    Kang, In-Sik

    The Precipitation Characteristics of ISCCP Tropical Weather States DONGMIN LEE GESTAR, University The authors examine the daytime precipitation characteristics of the International Satellite Cloud Climatology precipitation dataset used is the Tropical Rainfall Measuring Mission (TRMM) Multisatellite Precipitation

  10. Convective Heat Transport in Compressible Fluids

    E-Print Network [OSTI]

    Akira Furukawa; Akira Onuki

    2002-02-01

    We present hydrodynamic equations of compressible fluids in gravity as a generalization of those in the Boussinesq approximation used for nearly incompressible fluids. They account for adiabatic processes taking place throughout the cell (the piston effect) and those taking place within plumes (the adiabatic temperature gradient effect). Performing two-dimensional numerical analysis, we reveal some unique features of plume generation and convection in transient and steady states of compressible fluids. As the critical point is approached, overall temperature changes induced by plume arrivals at the boundary walls are amplified, giving rise to overshoot behavior in transient states and significant noises of the temperature in steady states. The velocity field is suggested to assume a logarithmic profile within boundary layers. Random reversal of macroscopic shear flow is examined in a cell with unit aspect ratio. We also present a simple scaling theory for moderate Rayleigh numbers.

  11. Convectively driven vortex flows in the Sun

    E-Print Network [OSTI]

    J. A. Bonet; I. Marquez; J. Sanchez Almeida; I. Cabello; V. Domingo

    2008-09-23

    We have discovered small whirlpools in the Sun, with a size similar to the terrestrial hurricanes (<~0.5 Mm). The theory of solar convection predicts them, but they had remained elusive so far. The vortex flows are created at the downdrafts where the plasma returns to the solar interior after cooling down, and we detect them because some magnetic bright points (BPs) follow a logarithmic spiral in their way to be engulfed by a downdraft. Our disk center observations show 0.009 vortexes per Mm^2, with a lifetime of the order of 5 min, and with no preferred sense of rotation. They are not evenly spread out over the surface, but they seem to trace the supergranulation and the mesogranulation. These observed properties are strongly biased by our type of measurement, unable to detect vortexes except when they are engulfing magnetic BPs.

  12. Ocean dynamics and thermodynamics in the tropical Indo- Pacific region

    E-Print Network [OSTI]

    Drushka, Kyla

    2011-01-01

    Pacific Oceans . . . . . . . . . . . . . . . . . . . . . . . . . . . . .in the eastern tropical Pacific Ocean associated with thethe western equatorial Pacific Ocean. J. Geophys. Res. , 96,

  13. 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

    2013-03-01

    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.

  14. The Relation Between Dry Vortex Merger and Tropical Cyclone Genesis over the Atlantic Ocean

    SciTech Connect (OSTI)

    Chen, Shu-Hua; Liu, Yi-Chin

    2014-10-27

    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.

  15. Paying a Visit: The Dalai Lama Effect on International Trade

    E-Print Network [OSTI]

    Fuchs, Andreas; Klann, Nils-Hendrik

    2011-01-26

    be negatively affected by a planned meeting between Dutch members of parliament and the Dalai Lama (“’We are clear: no dalai lama visits”, NRC Handelsblad, May 7th 2009, available at: http://www.nrc.nl/international/Features/article2234645.ece/We_are_clear_no... the results of the Wooldridge Test for Serial Autocorrelation, we reject the null hypothesis of ‘no first order autocorrelation’ in our sample. 17 covers the Hu Jintao era (2002-2008).37 This result is in line with the increased political and economic...

  16. Site Visit Report, Lawrence Livermore National Laboratory - February 2011 |

    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 on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX E LIST OF APPLICABLE DIRECTIVES Pursuant toPower WindDepartment of Energy Site Visit

  17. Foreign Visits & Assignments Guidelines | The Ames Laboratory

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverse (Journal Article) |FinalIndustrialFollowingFor yourMatteoForeign Visits &

  18. Tropical cyclone energy dispersion under vertical shears Xuyang Ge,1

    E-Print Network [OSTI]

    Li, Tim

    Tropical cyclone energy dispersion under vertical shears Xuyang Ge,1 Tim Li,1,2 and Xiaqiong Zhou1] Tropical cyclone Rossby wave energy dispersion under easterly and westerly vertical shears is investigated, and X. Zhou (2007), Tropical cyclone energy dispersion under vertical shears, Geophys. Res. Lett., 34, L

  19. LOW LEVEL JETS IN THE TROPICAL AMERICAS Submitted by

    E-Print Network [OSTI]

    Schubert, Wayne H.

    THESIS LOW LEVEL JETS IN THE TROPICAL AMERICAS Submitted by GABRIELA MORA ROJAS Department LEVEL JETS IN THE TROP- ICAL AMERICAS BE ACCEPTED AS FULFILLING IN PART REQUIREMENTS FOR THE DEGREE JETS IN THE TROPICAL AMERICAS The climatologies of five tropical low level jets are studied through

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

    E-Print Network [OSTI]

    Meyers, Steven D.

    Hurricane 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 as a tropical cyclone. #12;Hurricanes in Florida · 1851-2004 Florida's Hurricane Total: 110 Southwest Florida

  1. Hurricane Isaac, August 28, 2012/NOAA Tropical Cyclones

    E-Print Network [OSTI]

    Hurricane Isaac, August 28, 2012/NOAA Tropical Cyclones A PREPAREDNESS GUIDE U.S. DEPARTMENT, 6 of which became hurricanes East Pacific Ocean: 15 tropical storms, 8 of which became hurricanes Central Pacific Ocean: 4 tropical storms, 2 of which became hurricanes Over a typical 2-year period, the U

  2. Alien plant invasions in tropical and sub-tropical savannas: patterns, processes and prospects

    E-Print Network [OSTI]

    Foxcroft, Llewellyn C.; Richardson, David M.; Rejmánek, Marcel; Pyšek, Petr

    2010-01-01

    Tanzania Species Family Alien plant invasions in savannasLo pez-Olmedo et al. 2007). Alien plant invasions in Africanspecies of naturalised alien plants for tropical savannas in

  3. 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

  4. Climate Science: Tropical Expansion by Ocean Swing

    SciTech Connect (OSTI)

    Lu, Jian

    2014-04-01

    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.

  5. Chapter 4587 TROPICAL CYCLOGENESIS IN WIND SHEAR

    E-Print Network [OSTI]

    Nolan, David S.

    , it is shown that small values of wind shear in the range of 1.25 to 5 ms -1 are the most favorable, and very and middle troposphere, and a relatively small value of vertical wind shear, which is the change with heightChapter 4587 TROPICAL CYCLOGENESIS IN WIND SHEAR: CLIMATOLOGICAL RELATIONSHIPS AND PHYSICAL

  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.

    2011-11-01

    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. Survey and evaluation of techniques to augment convective heat transfer

    E-Print Network [OSTI]

    Bergles A. E.

    1965-01-01

    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 ...

  8. Experimental study of internal wave generation by convection in water

    E-Print Network [OSTI]

    2015-01-01

    wave generation by convection in water Michael Le Bars 1,2 ,investigate the dynamics of water cooled from below at 0 ° Cof the unusual property that water’s density maximum is at

  9. Experimental study of internal wave generation by convection in water

    E-Print Network [OSTI]

    Bars, Michael Le; Perrard, Stéphane; Ribeiro, Adolfo; Rodet, Laetitia; Aurnou, Jonathan M; Gal, Patrice Le

    2015-01-01

    We experimentally investigate the dynamics of water cooled from below at 0^oC and heated from above. Taking advantage of the unusual property that water's density maximum is at about 4^oC, this set-up allows us to simulate in the laboratory a turbulent convective layer adjacent to a stably stratified layer, which is representative of atmospheric and stellar conditions. High precision temperature and velocity measurements are described, with a special focus on the convectively excited internal waves propagating in the stratified zone. Most of the convective energy is at low frequency, and corresponding waves are localized to the vicinity of the interface. However, we show that some energy radiates far from the interface, carried by shorter horizontal wavelength, higher frequency waves. Our data suggest that the internal wave field is passively excited by the convective fluctuations, and the wave propagation is correctly described by the dissipative linear wave theory.

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

    SciTech Connect (OSTI)

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

    1981-04-01

    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.

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

    E-Print Network [OSTI]

    Overpeck, Scott Allen

    2001-01-01

    Weather forecasters have had difficulty forecasting mesoscale precipitation bands occurring in the regions of frontal zones. Within the last twenty years, slantwise convection (SC) through the release of conditional symmetric instability (CSI) has...

  12. TURBULENT CONVECTION IN STELLAR INTERIORS. III. MEAN-FIELD ANALYSIS...

    Office of Scientific and Technical Information (OSTI)

    implicit large eddy simulations of the turbulent convection in the envelope of a 5 Msub Sun red giant star and in the oxygen-burning shell of a 23 Msub Sun supernova...

  13. Fast Explicit Operator Splitting Method for Convection-Diffusion Equations

    E-Print Network [OSTI]

    Kurganov, Alexander

    to the one- and two-dimensional systems of convection-diffusion equations which model the polymer flooding) processes in fluid mechanics, astrophysics, me- teorology, multiphase flow in oil reservoirs, polymer flow

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

    E-Print Network [OSTI]

    Garai, Anirban

    2013-01-01

    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,

  15. 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 ...

  16. 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 ...

  17. Experimental Investigation of Natural Convection in Trombe Wall Systems 

    E-Print Network [OSTI]

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

    2006-01-01

    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...

  18. Use of a fictitious Marangoni number for natural convection simulation

    E-Print Network [OSTI]

    Arias, Francisco J.; Parks, Geoffrey T.

    2015-05-14

    - portance in many engineering and scientific applications such as energy transfer, boilers, nuclear reactor systems, energy storage devices, etc. In the design of such systems numerical simulation using computational fluid dynamics (CFD) and experimental... spacing of vertical, natural convection cooled, parallel plates. ASME J. Heat Transfer, 106 (1) (1984), pp. 116–123 [19] C.T. Tran, T.N. Dinh, Simulation of core melt pool formation in a reactor pressure vessel lower head using an effective convective...

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

    SciTech Connect (OSTI)

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

    1985-01-01

    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.

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

    SciTech Connect (OSTI)

    Canaan, R.E.

    1995-12-01

    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.

  1. Convective heat transfer in buildings: recent research results. Rev

    SciTech Connect (OSTI)

    Bauman, F.; Gadgil, A.; Kammerud, R.; Altmayer, E.; Nansteel, M.W.

    1982-10-01

    Recent experimental and numerical studies of convective heat transfer in buildings are described, and important results are presented. The experimental work has been performed on small-scale, water-filled enclosures; the numerical analysis results have been produced by a computer program based on a finite-difference scheme. The convective processes investigated in this research are: (1) natural convective heat transfer between room surfaces and the adjacent air, (2) natural convective heat transfer between adjacent rooms through a doorway or other openings, and (3) forced convection between the building and its external environment (such as wind-driven ventilation through windows, doors, or other openings). Results obtained at Lawrence Berkeley Laboratory (LBL) for surface convection coefficients are compared with existing ASHRAE correlations, and differences can have a significant impact on the accuracy of building energy analysis computer simulations. Interzone coupling correlations obtained from experimental work are in reasonable agreement with recently published experimental results and with earlier published work. Numerical simulations of wind-driven natural ventilation are presented. They exhibit good qualitative agreement with published wind-tunnel data.

  2. Thermal interaction between free convection and forced convection along a vertical conducting wall

    E-Print Network [OSTI]

    Shu, Jian-Jun

    2015-01-01

    A theoretical study is presented in this paper to investigate the conjugate heat transfer across a vertical finite wall separating two forced and free convection flows at different temperatures. The heat conduction in the wall is in the transversal direction and countercurrent boundary layers are formed on the both sides of the wall. The governing equations of this problem and their corresponding boundary conditions are all cast into a dimensionless form by using a non-similarity transformation. These resultant equations with multiple singular points are solved numerically using a very efficient singular perturbation method. The effects of the resistance parameters and Prandtl numbers on heat transfer characteristics are investigated.

  3. DOE/NNSA visits Mumbai in support of India's Global Center for...

    National Nuclear Security Administration (NNSA)

    visits Mumbai in support of India's Global Center for Nuclear Energy Partnership | National Nuclear Security Administration Facebook Twitter Youtube Flickr RSS People Mission...

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

    National Nuclear Security Administration (NNSA)

    Blog Home Field Offices Welcome to the NNSA Production Office NPO News Releases DOE Deputy Secretary and Rosatom Director Visit ... DOE Deputy Secretary and Rosatom...

  5. Is the duration of skin disease visits decreasing in the united states?

    E-Print Network [OSTI]

    Davis, Scott A; Feldman, Steven R; Fleischer Jr., Alan B

    2015-01-01

    2). Visits for impetigo, psoriasis, and unspecified disorderneoplasm of skin (216.9) Psoriasis (696.1) unspecifiedneoplasm of skin (216.9) Psoriasis (696.1) Unspecified

  6. Field Visit procedures -The Seminars and Training Committee/Scientific Committee

    E-Print Network [OSTI]

    Field Visit procedures - The Seminars and Training Committee/Scientific Committee shall in the course of the semester, such being upon consulting the modules' instructors. - The schedule shall

  7. EVIDENCE FOR CONVECTION IN SUNSPOT PENUMBRAE

    SciTech Connect (OSTI)

    Bharti, L.; Solanki, S. K.; Hirzberger, J.

    2010-10-20

    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.

  8. 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

    1995-01-01

    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...

  9. 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

  10. 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

  11. Establishing a Visiting Fellow Program at the VSoE Center for Robotics and Embedded Systems

    E-Print Network [OSTI]

    Zhou, Chongwu

    Establishing a Visiting Fellow Program at the VSoE Center for Robotics and Embedded Systems summary: Our proposal was to establish a visiting fellow program at the VSoE USC Center for Robotics, and scalable robotic systems, with broad and farreaching applications. CRES facilitates interdisciplinary

  12. 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 Ås. This opportunity arose from a bilateral agreement between the Governments of Norway and South Africa. For Gilbert

  13. 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

  14. Visit to the Yongbyon Nuclear Facilities in North Korea

    SciTech Connect (OSTI)

    Hecker, Siegfried S.

    2004-02-07

    Actions of the Government of the Democratic People's Republic of Korea have precipitated two nuclear crises in the past 10 years. The 1994 crisis was resolved through the 'Agreed Framework.' North Korea agreed to 'freeze' and eventually dismantle its nuclear program (with U.S. help to store spent fuel safely and under IAEA inspection). In return, the United States agreed (with the KEDO international consortium) to build two light-water reactors and supply North Korea with heavy-fuel oil until the reactors come on line. In addition, both sides agreed to move towards full normalization of relations, work for peace and security on a nuclear-free Korean Peninsula, and work on strengthening the international nonproliferation regime. The second nuclear crisis erupted when North Korean Government officials allegedly admitted to having a clandestine uranium enrichment program when confronted with this accusation by U.S. officials in October 2002. The United States (through KEDO) suspended heavy-fuel oil shipments and North Korea responded by expelling the IAEA inspectors, withdrawing from the Nuclear Nonproliferation Treaty, and restarting its nuclear program in January 2003. The North Korean Government has invited Professor John Lewis of Stanford University, a China and North Korea scholar, for Track I1 discussions of nuclear and other key issues since 1987. In August 2003, Professor Lewis visited North Korea just before the first six-party talks, which were designed by the United States to solve the current nuclear crisis. Professor Lewis was invited back for the January 2004 visit. He asked Jack Pritchard, former U.S. special envoy for DRPK negotiations, and me to accompany him. Two Asian affairs staff specialists from the U.S. Senate Foreign Relations Committee also joined us. I will report on the visit to the Yongbyon Nuclear Scientific Research Center on January 8,2004. We toured the 5 MWe reactor, the 50 MWe reactor construction site, the spent fuel pool storage building, and the radiochemical laboratory. We concluded that North Korea has restarted its 5 MWe reactor (which produces roughly 6 kg of plutonium annually), it removed the 8000 spent fuel rods that were previously stored under IAEA safeguards from the spent fuel pool, and that it most likely extracted the 25 to 30 kg of plutonium contained in these fuel rods. Although North Korean officials showed us what they claimed was their plutonium metal product from this reprocessing campaign, we were not able to conclude definitively that it was in fact plutonium metal and that it came from the most recent reprocessing campaign. Nevertheless, our North Korean hosts demonstrated that they had the capability, the facility and requisite capacity, and the technical expertise to produce plutonium metal. We were not shown any facilities or had the opportunity to talk to technical or military experts who were able to address the issue of whether or not North Korea had a 'deterrent' as claimed - that is, we were not able to conclude that North Korea can build a nuclear device and that it can integrate nuclear devices into suitable delivery systems. On the matter of uranium enrichment programs, Vice Minister Kim Gye Gwan categorically denied that North Korea has a uranium enrichment program - he said, 'we have no program, no equipment, and no technical expertise for uranium enrichment.' Upon return to the United States, I shared my observations and analysis with U.S. Government officials in Washington, DC, including congressional testimony to the Senate Foreign Relations Committee and briefings to two House of Representative Committees.

  15. 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.

  16. Turbulent Convection in Stellar Interiors. II. The Velocity Field

    E-Print Network [OSTI]

    David Arnett; Casey Meakin; P. A. Young

    2008-11-25

    We analyze stellar convection with the aid of 3D hydrodynamic simulations, introducing the turbulent cascade into our theoretical analysis. We devise closures of the Reynolds-decomposed mean field equations by simple physical modeling of the simulations (we relate temperature and density fluctuations via coefficients); the procedure (CABS, Convection Algorithms Based on Simulations) is terrestrially testable and is amenable to systematic improvement. We develop a turbulent kinetic energy equation which contains both nonlocal and time dependent terms, and is appropriate if the convective transit time is shorter than the evolutionary time scale. The interpretation of mixing-length theory (MLT) as generally used in astrophysics is incorrect; MLT forces the mixing length to be an imposed constant. Direct tests show that the damping associated with the flow is that suggested by Kolmogorov. The eddy size is approximately the depth of the convection zone, and this dissipation length corresponds to the "mixing length". New terms involving local heating by turbulent dissipation should appear in the stellar evolution equations. The enthalpy flux ("convective luminosity") is directly connected to the buoyant acceleration, and hence the velocity scale. MLT tends to systematically underestimate this velocity scale. Quantitative comparison with a variety of 3D simulations reveals a previously recognized consistency. Examples of application to stellar evolution will be presented in subsequent papers in this series.

  17. A simulation of convective dynamo in the solar convective envelope: Maintenance of the solar-like differential rotation and emerging flux

    SciTech Connect (OSTI)

    Fan, Yuhong; Fang, Fang

    2014-07-01

    We report the results of a magnetohydrodynamic (MHD) simulation of a convective dynamo in a model solar convective envelope driven by the solar radiative diffusive heat flux. The convective dynamo produces a large-scale mean magnetic field that exhibits irregular cyclic behavior with oscillation time scales ranging from about 5 to 15 yr and undergoes irregular polarity reversals. The mean axisymmetric toroidal magnetic field is of opposite signs in the two hemispheres and is concentrated at the bottom of the convection zone. The presence of the magnetic fields is found to play an important role in the self-consistent maintenance of a solar-like differential rotation in the convective dynamo model. Without the magnetic fields, the convective flows drive a differential rotation with a faster rotating polar region. In the midst of magneto-convection, we found the emergence of strong super-equipartition flux bundles at the surface, exhibiting properties that are similar to emerging solar active regions.

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

    Open Energy Info (EERE)

    Page Edit History Clarence Strait Tidal Energy Project, Tenax Energy Tropical Tidal Test Centre, Jump to: navigation, search 1 Retrieved from "http:en.openei.orgw...

  19. Nitrogen deposition in tropical forests from savanna and deforestation fires

    E-Print Network [OSTI]

    Chen, Y; Randerson, JT; Van Der Werf, GR; Morton, DC; Mu, M; Kasibhatla, PS

    2010-01-01

    15, Atkinson R (2000) Atmospheric chemistry of VOCs and NOx.tropics – impact on atmospheric chemistry and biogeochemicalimpact of fires on atmospheric chemistry. N r can be emitted

  20. "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...

  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.

    2012-09-04

    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. Performance-based assessment of daylight on tropical buildings- a case Study

    E-Print Network [OSTI]

    Szu Cheng, CHIEN

    2013-01-01

    Sustainability in the Tropics For the visual performance ofSustainability in the Tropics Table 3 Metrics conducted to assess dayliglzting performanceSustainability in the Tropics APPROACH Description of the case study model Daylight performance

  3. 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

  4. Diurnal Precipitation Regimes in the Global Tropics* KAZUYOSHI KIKUCHI AND BIN WANG

    E-Print Network [OSTI]

    Wang, Bin

    Diurnal Precipitation Regimes in the Global Tropics* KAZUYOSHI KIKUCHI AND BIN WANG Department tropical precipitation are documented by using two complementary Tropical Rainfall Measuring Mission (TRMM, and phase propagation characteristics of the diurnal precipitation. The oceanic regime is characterized

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

    E-Print Network [OSTI]

    Reynolds, Amber Elizabeth

    2009-05-15

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

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

    SciTech Connect (OSTI)

    Veil, J. A.; Environmental Science Division

    2007-09-30

    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.

  7. 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

    2012-01-06

    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.

  8. 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.

  9. Magneto-Vortex Dynamo Model in Solar convection zone

    E-Print Network [OSTI]

    Sergey V. Ershkov

    2011-01-06

    Here is presented a new magneto-vortex dynamo model for modeling & predicting of a processes in Solar plasma convection zone. Solar convection zone is located above the level r > 0,6-0,7 R, where R is a Solar radius. A key feature of such a model is that equation of Solar plasma motion as well as equation of magnetic fields evolution - are reduced to Helmholtz's vortex equation, which is up-graded in according with alpha-effect (Coriolis force forms an additional vorticity field or magnetic field due to Sun's differential rotation). Such an additional vorticity or magnetic field are proved to be concentrated at the proper belt in Solar convection zone under the influence of Coriolis force (at the middle latitudes of the Sun in respect to equator). Besides, such an an additional vorticity & magnetic fields are to be the basic sources of well-known phenomena "Maunder's butterfly" diagram.

  10. A meshless method for modeling convective heat transfer

    SciTech Connect (OSTI)

    Carrington, David B

    2010-01-01

    A meshless method is used in a projection-based approach to solve the primitive equations for fluid flow with heat transfer. The method is easy to implement in a MATLAB format. Radial basis functions are used to solve two benchmark test cases: natural convection in a square enclosure and flow with forced convection over a backward facing step. The results are compared with two popular and widely used commercial codes: COMSOL, a finite element model, and FLUENT, a finite volume-based model.

  11. Staggered grids discretization in three-dimensional Darcy convection

    E-Print Network [OSTI]

    B. Karasozen; A. D. Nemtsev; V. G. Tsybulin

    2008-02-17

    We consider three-dimensional convection of an incompressible fluid saturated in a parallelepiped with a porous medium. A mimetic finite-difference scheme for the Darcy convection problem in the primitive variables is developed. It consists of staggered nonuniform grids with five types of nodes, differencing and averaging operators on a two-nodes stencil. The nonlinear terms are approximated using special schemes. Two problems with different boundary conditions are considered to study scenarios of instability of the state of rest. Branching off of a continuous family of steady states was detected for the problem with zero heat fluxes on two opposite lateral planes.

  12. 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

    2010-04-01

    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.

  13. Semi-convection: What is the underlying physical context?

    E-Print Network [OSTI]

    Noels, Arlette

    2015-01-01

    Stellar conditions leading to a possible semi-convective mixing are discussed in three relevant cases: (1) low mass MS stars in which the CNO cycle takes progressively the lead over the PP chain due to the increase in temperature as core hydrogen burning proceeds, (2) massive MS stars which experience a large contri- bution of the radiation pressure to the total pressure and (3) core helium burning stars for which the production of carbon in the core increases the opacity. A short discussion of semi-convection in terms of instability of non radial modes follows.

  14. The influence of convective activity on the vorticity budget 

    E-Print Network [OSTI]

    Townsend, Tamara L

    1987-01-01

    . 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...

  15. Characterization of Trapped Lignin-Degrading Microbes in Tropical Forest Soil

    E-Print Network [OSTI]

    DeAngelis, Kristen

    2012-01-01

    of Trapped Lignin-Degrading Microbes in Tropical Forest Soilof Trapped Lignin-Degrading Microbes in Journals Tropicalof Trapped Lignin-Degrading Microbes in Tropical Forest Soil

  16. The impact of vertical shear on the sensitivity of tropical cyclogenes...

    Office of Scientific and Technical Information (OSTI)

    The impact of vertical shear on the sensitivity of tropical cyclogenesis to environmental rotation and thermodynamic state: TROPICAL CYCLOGENESIS AND SHEAR Citation Details...

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

    E-Print Network [OSTI]

    Bergles A. E.

    1962-01-01

    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. ...

  18. Influence of entrainment on the thermal stratification in simulations of radiative-convective equilibrium

    E-Print Network [OSTI]

    O'Gorman, Paul Ambrose

    Convective available potential energy (CAPE) is shown to increase rapidly with warming in simulations of radiative-convective equilibrium over a wide range of surface temperatures. The increase in CAPE implies a systematic ...

  19. THE DOMINANCE OF NEUTRINO-DRIVEN CONVECTION IN CORE-COLLAPSE...

    Office of Scientific and Technical Information (OSTI)

    THE DOMINANCE OF NEUTRINO-DRIVEN CONVECTION IN CORE-COLLAPSE SUPERNOVAE Citation Details In-Document Search Title: THE DOMINANCE OF NEUTRINO-DRIVEN CONVECTION IN CORE-COLLAPSE...

  20. Lake-size dependency of wind shear and convection as controls on gas exchange

    E-Print Network [OSTI]

    California at Santa Barbara, University of

    Lake-size dependency of wind shear and convection as controls on gas exchange Jordan S. Read,1 the relative contributions of wind shear (u*) and convection (w*) to turbulence in the surface mixed layer wind shear (u*/w*

  1. Tropical Forest Trust | Open Energy Information

    Open Energy Info (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 on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoop IncIowa (Utility Company) Jump to: navigation,PowerNetworksEnergia LtdaTropical

  2. SYNTHESIS A meta-analysis of impacts of alien vs. native plants on pollinator visitation and reproductive success of

    E-Print Network [OSTI]

    Traveset, Anna

    REVIEW AND SYNTHESIS A meta-analysis of impacts of alien vs. native plants on pollinator visitation@uib.es Abstract Alien plant species can alter pollinator visitation and, in turn, the sexual reproduction of 40 studies, we evaluated the effect of alien neighbour plant species (aliens) on visitation

  3. 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

  4. Neural Network forecasts of the tropical Pacific sea surface temperatures

    E-Print Network [OSTI]

    Hsieh, William

    Neural Network forecasts of the tropical Pacific sea surface temperatures Aiming Wu, William W Tang Jet Propulsion Laboratory, Pasadena, CA, USA Neural Networks (in press) December 11, 2005 title: Forecast of sea surface temperature 1 #12;Neural Network forecasts of the tropical Pacific sea

  5. CURRENT SKIPJACK OCEANOGRAPHY CRUISES IN EASTERN TROPICAL PACIFIC OCEAN

    E-Print Network [OSTI]

    CURRENT SKIPJACK OCEANOGRAPHY CRUISES IN EASTERN TROPICAL PACIFIC OCEAN F. Williams A series of skipjack oceanography cruises is planned for two offshore areas in the eastern tropical Pacific Ocean October 23 and arrived in Honolulu November 29; and the David Starr Jordan (Fishery-Oceanography C en t e

  6. Biological Oceanography of the Eastern Tropical Pacific: Summary

    E-Print Network [OSTI]

    540 Biological Oceanography of the Eastern Tropical Pacific: Summary of Existing Information Tuna Oceanography Research Program of the Institute of Marine Resources of the University of California Oceanography of the Eastern Tropical Pacific: Summary of Existing Information By MAURICE BLACKBURN tribution

  7. 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

  8. Tropical Moored Buoy Implementation Panel Scottish Association for Marine Science

    E-Print Network [OSTI]

    Tropical Moored Buoy Implementation Panel Scottish Association for Marine Science Oban, Scotland 26 September 2010 8:30 am Welcome and logistics 8:40 The Global Tropical Moored Buoy Array M. J. McPhaden, NOAA/PMEL, Seattle, USA 9:00 Current status of TRITON and m-TRITON buoy array and its data system K. Ando and I. Ueki

  9. Hybrid coupled modeling of the tropical Pacific using neural networks

    E-Print Network [OSTI]

    Hsieh, William

    Hybrid coupled modeling of the tropical Pacific using neural networks Shuyong Li, William W. Hsieh To investigate the potential for improving hybrid coupled models (HCM) of the tropical Pacific by the use: dynamical coupled models, statistical models and hybrid coupled models [Barnston et al., 1994]. A hybrid

  10. Ecological consequences of early Late Pleistocene megadroughts in tropical Africa

    E-Print Network [OSTI]

    Reiners, Peter W.

    Ecological consequences of early Late Pleistocene megadroughts in tropical Africa Andrew S. Cohen conditions in tropical Africa occurred in several discrete episodes between 135 and 90 ka, as demonstrated]. This resulted in extraordinarily low lake levels, even in Africa's deepest lakes. On the basis of well dated

  11. Southern Hemisphere Additional Ozonesondes (SHADOZ) 19982000 tropical ozone climatology

    E-Print Network [OSTI]

    Thompson, Anne

    Southern Hemisphere Additional Ozonesondes (SHADOZ) 1998­2000 tropical ozone climatology 2; published 31 January 2003. [1] The first view of stratospheric and tropospheric ozone variability in the Southern Hemisphere tropics is provided by a 3-year record of ozone soundings from the Southern Hemisphere

  12. Southern Hemisphere Additional Ozonesondes (SHADOZ) 19982004 tropical ozone climatology

    E-Print Network [OSTI]

    Thompson, Anne

    Southern Hemisphere Additional Ozonesondes (SHADOZ) 1998­2004 tropical ozone climatology: 3 more than 3000 ozone profiles from 14 tropical and subtropical sites using balloon- borne technique might cause small station-to-station biases in the total ozone measurement. We present further

  13. Climate change and tropical biodiversity: a new focus

    E-Print Network [OSTI]

    Wisenden, Brian D.

    Climate change and tropical biodiversity: a new focus Jedediah Brodie1 , Eric Post2 and William F, Australia Considerable efforts are focused on the consequences of climate change for tropical rainforests climatic changes and human land use) remain understudied. Key concerns are that aridification could

  14. Deep convection in the Irminger Sea forced by the Greenland tip jet

    E-Print Network [OSTI]

    Deep convection in the Irminger Sea forced by the Greenland tip jet Robert S. Pickart*, Michael A ........................................................................................................................................................................................................................... Open-ocean deep convection, one of the processes by which deep waters of the world's oceans are formed, the southwest Irminger Sea has been suggested as an additional location for open-ocean deep convection. The deep

  15. Deep convection and brine rejection in the Japan Sea Lynne D. Talley

    E-Print Network [OSTI]

    Talley, Lynne D.

    Deep convection and brine rejection in the Japan Sea Lynne D. Talley Scripps Institution groups. Japan Sea deep convection apparently occurs every winter, but massive renewal of bottom waters. Salyuk, P. Tishchenko, I. Zhabin, and S. Riser, Deep convection and brine rejection in the Japan Sea

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

    E-Print Network [OSTI]

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

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

    E-Print Network [OSTI]

    Cummer, Steven A.

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

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

    E-Print Network [OSTI]

    Gentine, Pierre

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

  19. The Role of Cumulus Convection in Hurricanes and its Representation in Hurricane Models

    E-Print Network [OSTI]

    Smith, Roger K.

    1 The Role of Cumulus Convection in Hurricanes and its Representation in Hurricane Models By Roger understanding of the role of cumulus convection in hurricanes as well as the various convective parameterization are able to simulate hurricane intensi cation with some degree of realism. In a weak vortex, the secondary

  20. 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

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

    E-Print Network [OSTI]

    Cummer, Steven A.

    Transient luminous events above two mesoscale convective systems: Charge moment change analysis. A. Rutledge, and D. R. MacGorman (2011), Transient luminous events above two mesoscale convective in the stratiform region of a mesoscale convective system (MCS) [Houze et al., 1990] by energetic positive CG (+CG

  2. The effect of increased convective entrainment on Asian monsoon biases in

    E-Print Network [OSTI]

    Wirosoetisno, Djoko

    The effect of increased convective entrainment on Asian monsoon biases in the MetUM General) The effect of increased convective entrainment on Asian monsoon biases in the MetUM General Circulation Model The effect of increased convective entrainment on Asian monsoon biases in the MetUM general circulation model

  3. Logarithmic corrections to scaling in turbulent thermal convection

    E-Print Network [OSTI]

    B. Dubrulle

    2001-01-04

    We use an analytic toy model of turbulent convection to show that most of the scaling regimes are spoiled by logarithmic corrections, in a way consistent with the most accurate experimental measurements available nowadays. This sets a need for the search of new measurable quantities which are less prone to dimensional theories.

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

    DOE Patents [OSTI]

    Pelton, B.A.; Siminovitch, M.

    1997-07-29

    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.

  5. Overshooting Convection from High-resolution NEXRAD Observations 

    E-Print Network [OSTI]

    Solomon, David

    2014-01-09

    are compared to the lapse-rate tropopause height calculated using the ERA-Interim reanalysis to determine if a storm is overshooting. We compute a 1-year analysis of overshooting convection at three-hour intervals for 2004 for the continental U.S. east...

  6. Investigation of the heat pipe arrays for convective electronic cooling 

    E-Print Network [OSTI]

    Howard, Alicia Ann Harris

    1993-01-01

    A combined experimental and analytical investigation was conducted to evaluate a heat pipe convective cooling device consisting of sixteen small copper/water heat pipes mounted vertically in a 4x4 array 25.4 mm square. The analytical portion...

  7. 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

  8. Evaporatively Driven Convection in a Draining Soap Film

    E-Print Network [OSTI]

    Bush, John W.M.

    Evaporatively Driven Convection in a Draining Soap Film Submitted by Jan M. Skotheim and John W. M. Bush, MIT A soap film was created by dipping a rectangular wire frame of height 3.5 cm and width 15 cm was mounted in a vertical po- sition, and the film drained under the influence of gravity in an unsaturated

  9. Simulation of Convection and Macrosegregation in a Large Steel Ingot

    E-Print Network [OSTI]

    Beckermann, Christoph

    convection and macrosegregation in casting of a large steel ingot are numerically simulated. The simulation of a shrinkage cavity at the top, is taken into account. The numerical results show the evolution macrosegregation observed in the lower part of the ingot. It is also shown that the inclusion of the shrinkage

  10. Nonequilibrium pattern formation and spatiotemporal chaos in fluid convection

    SciTech Connect (OSTI)

    Michael Cross

    2006-09-13

    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.

  11. 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

  12. UNCORRECTED Grid geometry effects on convection in ocean climate models

    E-Print Network [OSTI]

    Kuhlbrodt, Till

    is the 12 improvement of convection parameterization schemes, but the question of grid geometry also plays.elsevier.com/locate/omodol OCEMOD 100 No. of Pages 18, DTD = 4.3.1 28 August 2003 Type ARTICLE IN PRESS #12;UNCORRECTED PROOF 26 1 density gradient actually vanishes, one observes a strong vertical turbulent mixing to 32 depths of 2 km

  13. A CONVECTIVE HEAT TRANSFER MODEL FOR SIMULATION OF ROOMS WITH

    E-Print Network [OSTI]

    Quest Information and Learning Company 300 North Zeeb Road P.O. Box 1346 Ann Arbor, MI 48106-1346 by ProQuest Information and Learning Company. #12;II A CONVECTIVE HEAT TRANSFER MODEL FOR SIMULATION OF ROOMS. Seeing him grow gave me a new level of energy and hope. Without a doubt, my family members have been

  14. IMPACT OF AEROSOLS ON CONVECTIVE CLOUDS AND PRECIPITATION

    E-Print Network [OSTI]

    Zeng, Ning

    IMPACT OF AEROSOLS ON CONVECTIVE CLOUDS AND PRECIPITATION Wei-Kuo Tao,1 Jen-Ping Chen,2 Zhanqing Li effects on clouds could further extend to precipitation, both through the formation of cloud particles mechan- isms behind these effects, in particular, the ones connected to precipitation, are not yet well

  15. 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

    2005-03-22

    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...

  16. Gordon Bell visits Livermore, gets a look at the HPC revolution...

    National Nuclear Security Administration (NNSA)

    "nothing has changed since my first visit in 1961." But when it comes to high performance computing at LLNL, much has changed thanks to the computing technology revolution Bell...

  17. Chu Visits Site of America's First New Nuclear Reactor in Three...

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

    for nuclear energy in 2013, U.S. Secretary of Energy Steven Chu visited the Vogtle nuclear power plant in Waynesboro, Georgia and Oak Ridge National Laboratory to highlight the...

  18. Exploring Spatial Variations in the Relationship between National Park Visitation and Associated Factors in Texas Counties 

    E-Print Network [OSTI]

    Lee, Kyung Hee

    2013-11-07

    Recreation demand such as national park visitation is influenced by various social, demographic, and economic factors. These key variables are important indicators in predicting future trends and provide beneficial information about potential park...

  19. VisIt: An End-User Tool For Visualizing and Analyzing Very Large Data

    E-Print Network [OSTI]

    Atomic Energy Commission, CEA/CESTA Abstract. VisIt is a popular open source tool for visualizing National Supercomputing Center, Texas Advanced Computing Center, Atomic Weapons Establishment, ±French

  20. 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

  1. Chu Visits Site of America's First New Nuclear Reactor in Three...

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

    energy in 2013, U.S. Secretary of Energy Steven Chu visited the Vogtle nuclear power plant in Waynesboro, Georgia and Oak Ridge National Laboratory to highlight the steps the...

  2. Lacunarity as a texture measure for a tropical forest landscape

    SciTech Connect (OSTI)

    Su, Haiping; Krummel, J.

    1996-01-01

    Fragmentation and loss of tropical forest cover alters terrestrial plant and animal population dynamics, reduces biodiversity and carbon storage capacity, and, as a global phenomenon could affect regional and global climate patterns. Lacunarity as a texture measure can offer a simple solution to characterize the texture of tropical forest landscape and determine spatial patterns associated with ecological processes. Lacunarity quantifies the deviation from translational invariance by describing the distribution of gaps within a binary image at multiple scales. As lacunarity increases, the spatial arrangement of tropical forest gaps will also increase. In this study, we used the Spatial Modeler in Imagine as a graphic programming tool to calculate lacunarity indices for a tropical forest landscape in Southern Mexico and Northern Guatemala. Lacunarity indices were derived from classified Landsat MSS images acquired in 1974 and 1984. Random-generated binary images were also used to derive lacunarity indices and compared with the lacunarity of forest patterns derived from the classified MSS images. Tropical forest area declined about 17%, with most of the forest areas converted into pasture/grassland for grazing. During this period, lacunarity increased about 25%. Results of this study suggest that tropical forest fragmentation could be quantified with lacunarity measures. The study also demonstrated that the Spatial Modeler can be useful as a programming tool to quantify spatial patterns of tropical forest landscape by using remotely sensed data.

  3. The Spectral Amplitude of Stellar Convection and its Scaling in the High-Rayleigh-Number Regime

    E-Print Network [OSTI]

    Featherstone, Nicholas A

    2015-01-01

    Convection plays a central role in the dynamics of any stellar interior, and yet its operation remains largely-hidden from direct observation. As a result, much of our understanding concerning stellar convection necessarily derives from theoretical and computational models. The Sun is, however, exceptional in that regard. The wealth of observational data afforded by its proximity provides a unique testbed for comparing convection models against observations. When such comparisons are carried out, surprising inconsistencies between those models and observations become apparent. Both photospheric and helioseismic measurements suggest that convection simulations may overestimate convective flow speeds on large spatial scales. Moreover, many solar convection simulations have difficulty reproducing the observed solar differential rotation due to this apparent overestimation. We present a series of 3-dimensional (3-D) stellar convection simulations designed to examine how the amplitude and spectral distribution of ...

  4. Timescale of asteroid resurfacing by regolith convection resulting from the impact-induced global seismic shaking

    E-Print Network [OSTI]

    Yamada, Tomoya M; Morota, Tomokatsu; Katsuragi, Hiroaki

    2015-01-01

    A model for the asteroid resurfacing by regolith convection is built to estimate its timescale. In the model, regolith convection is driven by the impact-induced global seismic shaking. The model consists of three steps: (i) intermittent impact of meteors, (ii) impact-induced global vibration (seismic shaking), and (iii) vibration-induced regolith convection. In order to assess the feasibility of the resurfacing process driven by the regolith convection, we estimate the resurfacing timescale as a function of the size of a target asteroid. According to the estimated result, the regolith-convection-based resurfacing timescale is sufficiently shorter than the mean collisional lifetime for the main belt asteroids. This means that the regolith convection is a possible mechanism for the asteroid resurfacing process. However, the timescale depends on various uncertain parameters such as seismic efficiency and convective roll size. To clarify the parameter dependences, we develop an approximated scaling form for the ...

  5. Tropical Cloud Properties and Radiative Heating Profiles

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

    Mather, James

    2008-01-15

    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.

  6. 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.

  7. A tropical influence on global climate

    SciTech Connect (OSTI)

    Schneider, E.K.; Kirtman, B.P.; Lindzen, R.S.

    1997-05-15

    A potential influence of tropical sea surface temperature on the global climate response to a doubling of the CO{sub 2} concentration is tested using an atmospheric general circulation model coupled to a slab mixed layer ocean. The warming is significantly reduced when sea surface temperatures in the eastern equatorial Pacific cold tongue region between latitudes 2.25{degrees}N and 2.25{degrees}S are held at the control simulation values. Warming of the global mean temperature outside of the cold tongue region is reduced from 2.4{degrees}C in the unconstrained case to 1.9{degrees}C when the sea surface temperature constraint is applied. The decrease in the warming results from a positive net heat flux into the ocean cold tongue region and implicit heat storage in the subsurface ocean, induced by horizontal atmospheric heat fluxes. The reduced surface temperature warming outside of the cold tongue region is due to reduction in the downward longwave radiative flux at the surface, caused in turn by reduced atmospheric temperature and moisture. The global mean surface temperature responds to the heat storage in the ocean as if the global mean radiative forcing due to the doubled CO{sub 2} (approximately 4 W m{sup {minus}2}) was reduced by the value of the global mean heat flux into the ocean. This mechanism also provides a possible explanation for the observed high correlation on interannual timescales between the global mean tropospheric temperature and sea surface temperature in the eastern tropical Pacific. The results emphasize the importance of correctly modeling the dynamical processes in the ocean and atmosphere that help determine the sea surface temperature in the equatorial eastern Pacific, in addition to the thermodynamical processes, in projecting global warming. 23 refs., 8 figs.

  8. Numerical study of thermoacoustic convection in a cavity

    SciTech Connect (OSTI)

    Fusegi, Toru; Farouk, B.; Oran, E.S.

    1995-12-31

    Thermoacoustic convection in a two-dimensional cavity is numerically studied. Part of a compressible fluid (Helium) near the center line of the cavity is suddenly energized to generate pressure waves. Numerical solutions are secured by employing a highly accurate explicit method termed LCPFCT algorithm for the convection terms of the full Navier-Stokes equations. Thermoacoustic waves, which decay in large time due to the viscosity of fluid, are of the oscillatory nature. Much higher heat transfer rate can be achieved in an initial stage of transient processes, compared to that due to conduction. When a partial length of the cavity center line is heated, resulting thermoacoustic waves exhibit remarkable two-dimensional patterns.

  9. Thermodynamic properties of mesoscale convective systems observed during BAMEX

    SciTech Connect (OSTI)

    Correia, James; Arritt, R.

    2008-11-01

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

  10. Influence of geometry on natural convection in buildings

    SciTech Connect (OSTI)

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

    1985-01-01

    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.

  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

    2010-04-10

    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. Prandtl Number Dependent Natural Convection with Internal Heat Sources

    SciTech Connect (OSTI)

    Kang Hee Lee; Seung Dong Lee; Kune Y. Suh; Joy L. Rempe; Fan-Bill Cheung; Sang B. Kim

    2004-06-01

    Natural convection plays an important role in determining the thermal load from debris accumulated in the reactor vessel lower head during a severe accident. Recently, attention is being paid to the feasibility of external vessel flooding as a severe accident management strategy and to the phenomena affecting the success path for retaining the molten core material inside the vessel. The heat transfer inside the molten core material can be characterized by the strong buoyancy-induced flows resulting from internal heating due to decay of fission products. The thermo-fluid dynamic characteristics of such flow depend strongly on the thermal boundary conditions. The spatial and temporal variation of heat flux on the pool wall boundaries and the pool superheat are mainly characterized by the natural convection flow inside the molten pool. In general, the natural convection heat transfer phenomena involving the internal heat generation are represented by the modified Rayleigh number (Ra’), which quantifies the internal heat source and hence the strength of the buoyancy force. In this study, tests were conducted in a rectangular section 250 mm high, 500 mm long and 160 mm wide. Twenty-four T-type thermocouples were installed in the test section to measure temperatures. Four T-type thermocouples were used to measure the boundary temperatures. The thermocouples were placed in designated locations after calibration. A direct heating method was adopted in this test to simulate the uniform heat generation. The experiments covered a range of Ra' between 1.5x106 and 7.42x1015 and the Prandtl number (Pr) between 0.7 and 6.5. Tests were conducted with water and air as simulant. The upper and lower boundary conditions were maintained uniform. The results demonstrated feasibility of the direct heating method to simulate uniform volumetric heat generation. Particular attentions were paid to the effect of Pr on natural convection heat transfer within the rectangular pool.

  13. Gradients of meteorological parameters in convective and nonconvective areas 

    E-Print Network [OSTI]

    McCown, Milton Samuel

    1976-01-01

    involve horizontal gradients. For example, the equations of motion relate wind speed to pressure gradient, and the thermal wind equation relates vertical wind shear to the horizontal temperature gradient. The study of gradients may help... GRADIENTS OF METEOROLOGICAL PARAMETERS IN CONVECTIVE AND NONCONVECTIVE AREAS A Thesis by Milton Samuel McCown Submitted to the Graduate College of Texas ASM University in partial fulfillment of the requirement for the degree of MASTER...

  14. Investigation of convective activity by means of sferics 

    E-Print Network [OSTI]

    Snyder, Louis Archie

    1958-01-01

    that the associ- ation between sfarics data and convective activity may be better inter- prefed and thus extend our knowledge of this problem, PRESENT STATUS OF KNOWLEDGE Atmospherics or "sferics, " commonly associated with radio static, are electromagnetic... east of El Dorado, Oklahoma (20 miles southwest of Altus), at 1918 CST. The echo south of Altus (Fi. g. 26) appeared to be associated with this tornado even though only a weak sferics bearing was recorded at the time. Further study of the sferics...

  15. Deep meridional circulation below the solar convective envelope

    E-Print Network [OSTI]

    K. M. Hiremath

    2008-03-08

    With reasonable assumptions and approximations, we compute the velocity of the meridional flow $U$ in the convective envelope by modified Chandrasekhar's (1956) MHD equations. The analytical solution of such a modified equation is found to be $U(x,\\mu) = \\sum_{n=0}^\\infty \\bigl[u1_n x^n + u2_n x^{-(n+3)}\\bigr] C_n^{3/2}(\\mu)$, where $x$ is non-dimensional radius, $\\mu = cos{\\vartheta}$, ${\\vartheta}$ is the co-latitude, $C_n^{3/2} {(\\mu)}$ are the Gegenbaur polynomials of order 3/2, $u1_n$ and $u2_n$ are the unknown constants. The results show that meridional velocity flow from the surface appears to penetrates deep below base of the convective envelope and at outer part of the radiative zone. With such a deep flow velocity below the convective envelope and a very high density stratification in the outer part of the radiative zone with likely existence of a strong ($\\sim$ $10^{4}$ G) toroidal magnetic field structure, the velocity of transport of meridional flow is considerably reduced. Hence, it is very unlikely that the return flow will reach the surface (with a period of solar cycle) as required by some of the flux transport dynamo models. On the other hand, deep meridional flow is required for burning of Lithium at outer part of the radiative zone supporting the observed Lithium deficiency at the surface.

  16. New dynamics of the Sun convection zone and global warming

    E-Print Network [OSTI]

    Bershadskii, A

    2008-01-01

    Solar activity is studied using cluster analysis of the sunspot number time-fluctuations. It is shown that for a Historic period (1850-1932yy) the cluster exponent $\\alpha \\simeq 0.37$ (strong clustering) for the high activity components of the solar cycles, whereas for a Modern period (last seven solar cycles: 1933-2007) the cluster exponent $\\alpha \\simeq 0.50$ (random, white noise-like situation). Then, comparing these results with the corresponding data from the classic laboratory convection experiments it is shown, that for the Historic period emergence of the sunspots in the solar photosphere was strongly dominated by turbulent photospheric convection. For the Modern period, this domination was broken by a new more active dynamics of the inner layers of the convection zone. Then, it is shown that the dramatic change of the sun dynamics in the transitional period (between the Historic and Modern periods, solar cycle 1933-1944yy) had clear detectable impact on the global Earth climate at this period. Name...

  17. Persistent drying in the tropics linked to natural forcing

    E-Print Network [OSTI]

    Winter, Amos; Zanchettin, Davide; Miller, Thomas; Kushnir, Yochanan; Black, David; Lohmann, Gerrit; Burnett, Allison; Haug, Gerald H.; Estrella-Martínez, Juan; Breitenbach, Sebastian F. M.; Beaufort, Luc; Rubino, Angelo; Cheng, Hai

    2015-07-14

    Approximately half of the world’s population lives in the tropics, and future changes in the hydrological cycle will impact not just the freshwater supplies but also energy production in areas dependent upon hydroelectric power. It is vital...

  18. Eddy formation and propagation in the eastern tropical Pacific 

    E-Print Network [OSTI]

    Jhingran, Vikas Gopal

    1997-01-01

    Observations of eddies in the eastern tropical Pacific from TOPEX altimetry data show that there are seasonal and interannual variations in eddy activity. Comparisons between time of eddy formation and corresponding wind ...

  19. Reduction of tropical land region precipitation variability via transpiration

    E-Print Network [OSTI]

    Lee, Jung-Eun

    Tropical rainforests are known to exhibit low intraseasonal precipitation variability compared with oceanic areas with similar mean precipitation in observations and models. In the present study, the potential role of ...

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

    E-Print Network [OSTI]

    Worbs, H. E.

    1987-01-01

    . Another consideration is the high ventilation loads due to cooling the moist air prevalent in semi-tropical climates. This paper describes a computer program which assesses all the pertinent variables which comprise the annual heating and cooling energy...

  1. Hyperspectral Remote Sensing of Tropical Grass Quality and Quantity

    E-Print Network [OSTI]

    Hyperspectral Remote Sensing of Tropical Grass Quality and Quantity Onisimo Mutanga 7 April 2004, The Netherlands Prof. W. J. Bond University of Cape Town, South Africa #12;Hyperspectral Remote Sensing 1.2 Hyperspectral remote sensing

  2. Energy Design Guidelines for High Performance Schools: Tropical Island Climates

    SciTech Connect (OSTI)

    2004-11-01

    Design guidelines outline high performance principles for the new or retrofit design of K-12 schools in tropical island climates. By incorporating energy improvements into construction or renovation plans, schools can reduce energy consumption and costs.

  3. Tropical cyclone precipitation risk in the Southern United States

    E-Print Network [OSTI]

    Shedd, Sandra Michael

    2015-01-01

    This thesis works to evaluate the new rainfall algorithm that is used to simulate longterm tropical cyclone precipitation (TCP) climatology throughout the southeastern United States. The TCP climatology is based on a fleet ...

  4. Future precipitation changes and their implications for tropical peatlands

    E-Print Network [OSTI]

    Yang, Zong-Liang

    Future precipitation changes and their implications for tropical peatlands Wenhong Li,1 Robert E. Dickinson, R. Fu, G.-Y. Niu, Z.-L. Yang, and J. G. Canadell (2007), Future precipitation changes

  5. Precipitable water structure in tropical systems as estimated from TOVS 

    E-Print Network [OSTI]

    Hatfield, Eric

    1994-01-01

    The spatial and temporal structures of precipitable water (pW) in tropical systems are estimated using TIROS Operational Vertical Sounder (TOVS) radiances over ten cool seasons and two entire years. Statistical regression ...

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

    SciTech Connect (OSTI)

    Dudhia, Jimy

    2013-03-12

    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.

  7. 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

  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. Describing the Heat Transport of Turbulent Rayleigh--B\\'enard Convection by POD methods

    E-Print Network [OSTI]

    Lülff, Johannes

    2015-01-01

    Rayleigh--B\\'enard convection, which is the buoyancy-induced motion of a fluid enclosed between two horizontal plates, is an idealised setup to study thermal convection. We analyse the modes that transport the most heat between the plates by computing the proper orthogonal decomposition (POD) of numerical data. Instead of the usual POD ansatz of finding modes that describe the energy best, we propose a method that is optimal in describing the heat transport. Thereby, we can determine the modes with the major influence on the heat transport and the coherent structures in the convection cell. We also show that in lower-dimensional projections of numerical convection data, the newly developed modes perform consistently better than the standard modes. We then use this method to analyse the main modes of three-dimensional convection in a cylindrical vessel as well as two-dimensional convection with varying Rayleigh number and varying aspect ratio.

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

    SciTech Connect (OSTI)

    Zhang Chunguang; Deng Licai; Xiong Darun; Christensen-Dalsgaard, Jorgen

    2012-11-01

    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.

  11. Simulation of directional solidification, thermochemical convection, and chimney formation in a Hele-Shaw cell

    E-Print Network [OSTI]

    Worster, M. Grae

    Simulation of directional solidification, thermochemical convection, and chimney formation and the Enthalpy Method throughout the computational domain allows us to avoid prescribing internal boundary

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

    E-Print Network [OSTI]

    Shaw, Justin David

    2000-01-01

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

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

    SciTech Connect (OSTI)

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

    2014-10-08

    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.

  14. 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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would like submit the followingConcentratingPortal ControllingConvection feedbacks in a

  15. 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

  16. GE Hosts Visit by DOE to Kick Off High-Efficiency GeneratorDevelopment Program

    E-Print Network [OSTI]

    history of working with the DOE on critical energy programs. Jon Ebacher, Vice President of GE PowerGE Hosts Visit by DOE to Kick Off High-Efficiency GeneratorDevelopment Program Technology Expected of Energy (DOE) recently met with representatives of GE Power Systems and the GE Global Research Center

  17. VisIt: An End-User Tool for Visualizing and Analyzing Very Large Data

    SciTech Connect (OSTI)

    Childs, Hank [Lawrence Berkeley National Laboratory (LBNL); Brugger, Eric [Lawrence Livermore National Laboratory (LLNL); Whitlock, B. [Lawrence Livermore National Laboratory (LLNL); Meredith, Jeremy S [ORNL; Ahern, Sean [ORNL; Bonnell, Kathleen [Lawrence Livermore National Laboratory (LLNL); Miller, Mark [Lawrence Livermore National Laboratory (LLNL); Weber, G. [Lawrence Berkeley National Laboratory (LBNL); Harrison, Cyrus [Lawrence Livermore National Laboratory (LLNL); Pugmire, Dave [ORNL; Fogal, T. [University of Utah; Garth, Christoph [unknown; Sanderson, Allen [University of Utah; Bethel, E Wes [Lawrence Berkeley National Laboratory (LBNL); Durant, Marc [Tech-X Corporation; Camp, David [Lawrence Berkeley National Laboratory (LBNL); Favre, Jean M. [Swiss National Supercomputing Center; Ruebel, O [unknown; Navratil, Paul [Texas Advanced Computing Center; Wheeler, Matthew [Atomic Weapons Establishment; Selby, Paul [Atomic Weapons Establishment; Vivodtzev, Fabien [CEA, France

    2011-01-01

    VisIt is a popular open source tool for visualizing and analyzing data. It owes its success to its foci of increasing data understanding, large data support, and providing a robust and usable product, as well as its underlying design that fits today's supercomputing landscape. In this short paper, we describe the VisIt project and its accomplishments. The VisIt project's three focal points - understanding data, large data, and delivering a product - together form a powerful environment for analyzing data from HPC simulations. It is used in varied ways: it enables visualization scientists, computational code developers, and the physicists that run these codes to perform a broad range of data understanding activities, including debugging, making movies, and exploring data. The user interface portion of its design provides a powerful paradigm for analyzing data while the data processing portion of its design is well suited for big data. This in turn has led to many successes: in scaling up to high levels of concurrency and large data sizes, in providing a 'home' for large data algorithms, in understanding how to best use supercomputers, and, most importantly, in helping users understand their data. Further, despite significant upcoming changes in supercomputing architecture, VisIt's future appears bright, as it enjoys vibrant user and developer communities.

  18. Secretary Chu, EM’s Huizenga and Other DOE Officials Visit Catholic University's Laboratory

    Broader source: Energy.gov [DOE]

    WASHINGTON, D.C. – Dave Huizenga, head of the Department of Energy (DOE) Office of Environmental Management (EM), was part of a DOE delegation led by Secretary of Energy Steven Chu that visited Catholic University’s Vitreous State Laboratory (VSL) this week.

  19. Getting Started 1) Visit the Java VChill website at http://chill.colostate.edu/java/

    E-Print Network [OSTI]

    Rutledge, Steven

    VCHILL Getting Started 1) Visit the Java VChill website at http://chill.colostate.edu/java/ 2) Click on "Launch VChill" (you will see Java start up * ) 3) Enter signon name (password dialog pops up bookmark case * If it does not, you may need to install Java first. Click on the Download Center link (in

  20. 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

  1. 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

  2. Differences in flower visitation networks between an oceanic and a continental island

    E-Print Network [OSTI]

    Traveset, Anna

    communities of each of two different island systems: the Canary Islands (oceanic origin) and the BalearicDifferences in flower visitation networks between an oceanic and a continental island ROCÍO CASTRO, Mallorca, Balearic Islands, Spain Received 27 May 2013; revised 28 October 2013; accepted for publication

  3. Bower paint removal leads to reduced female visits, suggesting bower paint functions as a chemical signal

    E-Print Network [OSTI]

    Borgia, Gerald

    Bower paint removal leads to reduced female visits, suggesting bower paint functions as a chemical unique display elements, bower painting, has received relatively little attention despite males' large of masticated vegetation and male saliva or `bower paint' to a chest-high band inside their bower walls

  4. "When I came to visit the campus, I went through the facilities at Grice Marine Lab,

    E-Print Network [OSTI]

    Kunkle, Tom

    "When I came to visit the campus, I went through the facilities at Grice Marine Lab, and talked with giving her a specific focus in marine biology. "Since high school I've been interested in coral reefs of courses required for the marine biology major, including Oceanography and General Ecology. She

  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-

    1996-01-01

    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. 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

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

    E-Print Network [OSTI]

    Dahl, Kristina Ariel

    2005-01-01

    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 ...

  8. A climatology of tropical synoptic scale behavior from TOVS-estimated precipitable water 

    E-Print Network [OSTI]

    Mackey, Morgan Douglas

    1996-01-01

    Tropical synoptic scale behavior is examined using 3 to 8 day filtered precipitable water (PW) estimated from TOVS operational satellite observations for 24 three-month seasons. Zonally-oriented tropical convergence zones ...

  9. The role of piscivores in a species-rich tropical river 

    E-Print Network [OSTI]

    Layman, Craig Anthony

    2004-11-15

    Much of the world's species diversity is located in tropical and sub-tropical ecosystems, and a better understanding of the ecology of these systems is necessary to stem biodiversity loss and assess community- and ...

  10. 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 ...

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

    E-Print Network [OSTI]

    Rafter, Patrick Anthony

    2009-01-01

    eastern equatorial Pacific Ocean during the past 3 M.Y. ,in the western tropical Pacific Ocean in the Holocene epoch,eastern tropical North Pacific Ocean, Mar. Chem. , 3, 271–

  12. The Mechanism of First Raindrops Formation in Deep Convective Clouds

    SciTech Connect (OSTI)

    Khain, Alexander; Prabha, Thara; Benmoshe, Nir; Pandithurai, G.; Ovchinnikov, Mikhail

    2013-08-22

    The formation of first raindrops in deep convective clouds is investigated. A combination of observational data analysis and 2-D and 3-D numerical bin microphysical simulations of deep convective clouds suggests that the first raindrops form at the top of undiluted or slightly diluted cores. It is shown that droplet size distributions in these regions are wider and contain more large droplets than in diluted volumes. The results of the study indicate that the initial raindrop formation is determined by the basic microphysical processes within ascending adiabatic volumes. It allows one to predict the height of the formation of first raindrops considering the processes of nucleation, diffusion growth and collisions. The results obtained in the study explain observational results reported by Freud and Rosenfeld (2012) according to which the height of first raindrop formation depends linearly on the droplet number concentration at cloud base. The results also explain why a simple adiabatic parcel model can reproduce this dependence. The present study provides a physical basis for retrieval algorithms of cloud microphysical properties and aerosol properties using satellites proposed by Rosenfeld et al. ( 2012). The study indicates that the role of mixing and entrainment in the formation of the first raindrops is not of crucial importance. It is also shown that low variability of effective and mean volume radii along horizontal traverses, as regularly observed by in situ measurements, can be simulated by high-resolution cloud models, in which mixing is parameterized by a traditional 1.5 order turbulence closure scheme.

  13. The annual cycle in equatorial convection and sea surface temperature

    SciTech Connect (OSTI)

    Mitchell, T.P.; Wallace, J.M. (Washington Univ., Seattle (United States) NASA, Goddard Space Flight Center, Greenbelt, MD (United States))

    1992-10-01

    The coupled atmosphere-ocean system in the equatorial eastern Pacific and Atlantic exhibits a distinct annual cycle that is reflected in contrasting conditions at the times of the two equinoxes. The contrasts are so strong that they dominate the annual march of zonally averaged outgoing long wave radiation for the equatorial belt. The March equinox corresponds to the warm season when the equatorial cold tongues in the eastern Pacific and Atlantic area absent. With the onset of summer monsoon convection over Colombia, Central America, and West Africa in May-June, northward surface winds strengthen over the eastern Pacific and Atlantic, the equatorial cold tongues reappear, and the marine convection shifts from the equatorial belt to the intertropical convergence zones (ITCZs) along 8 deg N. On the basis of observational evidence concerning the timing and year-to-year regularity of the surface wind changes during the development of the cold tongues, it is argued that (1) the increase in the northward surface winds in response to the onset of the northern summer monsoon may be instrumental in reestablishing the cold tongues, and (2) positive feedbacks involving both the zonal and meridional wind components contribute to the remarkable robustness of the cold tongue-ITCZs complexes in both oceans. 36 refs.

  14. 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.

  15. 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

    2012-01-19

    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.

  16. Tropical cyclone motion and recurvature in TCM-90. Master's thesis

    SciTech Connect (OSTI)

    Fitzpatrick, M.E.

    1992-01-01

    Rawinsonde and satellite data collected during the Tropical Cyclone Motion (TCM90) experiment, which was conducted during the summer of 1990 in the Western North pacific, is used to examine tropical cyclone steering motion and recurvature. TCM-90 composite results are compared with those found in a composite study using twenty-one years (1957-77) of Western North Pacific rawinsonde data during the same August-September period and also for all months during this same 21-year period. Both data sets indicate that the composite deep-layer-mean (850-300 mb) winds 5-7 deg from the cyclone center provide an important component of the steering flow for tropical cyclones. However, despite the rawinsonde data enhancements of the TCM-90 experiment, data limitations prevented an accurate observation of steering flow conditions at individual time periods or for the average of only 5-10 time periods when composited together.

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

    E-Print Network [OSTI]

    Cummer, Steven A.

    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

  18. 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

  19. Simulation of Convection and Macrosegregation in Steel Casting C. Beckermann* and M. C. Schneider**

    E-Print Network [OSTI]

    Beckermann, Christoph

    Simulation of Convection and Macrosegregation in Steel Casting C. Beckermann* and M. C. Schneider.C., "Simulation of Convection and Macrosegregation in Steel Casting," in Proceedings of the 50th SFSA Technical and the mushy zone. This is particularly true in heavy steel castings which have very large cross sections

  20. Global warming, convective threshold and false thermostats Ian N. Williams,1

    E-Print Network [OSTI]

    Global warming, convective threshold and false thermostats Ian N. Williams,1 Raymond T thermostats. Citation: Williams, I. N., R. T. Pierrehumbert, and M. Huber (2009), Global warming, convective. To first order this consists of a shift to warmer temperatures as climate warms, without change of shape

  1. The influence of the transition zone water filter on convective circulation in the mantle

    E-Print Network [OSTI]

    The influence of the transition zone water filter on convective circulation in the mantle Garrett M 2004. [1] The ``transition zone water filter'' model of mantle convection attempts to reconcile bulk mass and heat transfer across mantle interfaces. Here we test the basic effect of the water filter

  2. A STRONGLY DEGENERATE CONVECTION-DIFFUSION PROBLEM MODELING CENTRIFUGATION OF FLOCCULATED SUSPENSIONS

    E-Print Network [OSTI]

    A STRONGLY DEGENERATE CONVECTION-DIFFUSION PROBLEM MODELING CENTRIFUGATION OF FLOCCULATED of BV entropy solutions of a strongly degenerate convection-di#11;usion problem modeling centrifugation- boundary value problem numerically, i.e., to simulate the centrifugation process. 1. Introduction We

  3. Evidence that solar wind fluctuations substantially affect global convection and substorm occurrence

    E-Print Network [OSTI]

    California at Berkeley, University of

    that this implies that solar wind ULF power may be an important contributor to the strength of coupling of solar for the connection between iono- spheric convection and solar wind ULF power. The high correlations between ULF powerEvidence that solar wind fluctuations substantially affect global convection and substorm

  4. Influences of Precipitation on Water Mass Transformation and Deep Convection MICHAEL A. SPALL

    E-Print Network [OSTI]

    Influences of Precipitation on Water Mass Transformation and Deep Convection MICHAEL A. SPALL for the temperature and salinity anomalies of deep convective water masses, making explicit their dependence on both on water mass transformation and the strength of the meridional over- turning circulation in marginal seas

  5. Adaptive Thermal Management for Portable System Batteries by Forced Convection Cooling

    E-Print Network [OSTI]

    Pedram, Massoud

    Adaptive Thermal Management for Portable System Batteries by Forced Convection Cooling Qing Xie a portable system. Since the cooling fan is also powered by the same battery, it is critical to develop thermal management problem for batteries (ATMB) in the portable systems with forced convection cooling

  6. Thermal convection with a freely moving top boundary Jin-Qiang Zhong

    E-Print Network [OSTI]

    Zhang, Jun

    Thermal convection with a freely moving top boundary Jin-Qiang Zhong Department of Physics, New; accepted 29 September 2005; published online 22 November 2005 In thermal convection, coherent flow-organization. They range from small-scale thermal plumes that are produced near both the top and the bottom boundaries

  7. 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

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

    E-Print Network [OSTI]

    Knievel, Jason Clark

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

  9. Hydrodynamical simulations of penetrative convection and generation of internal gravity waves

    E-Print Network [OSTI]

    Stêpieñ, Kazimierz

    Hydrodynamical simulations of penetrative convection and generation of internal gravity waves M investigate the generation of internal gravity waves in the stable region below a convective layer by means of angular momentum from the place where the waves are generated to the region of their dissipation, which

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

    SciTech Connect (OSTI)

    Zhang, Guang J [Scripps Institution of Oceanography

    2013-07-29

    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.

  11. 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

  12. Resolving Convection in a Global Hypohydrostatic Model by S. T. Garner1

    E-Print Network [OSTI]

    Vallis, Geoff

    -resolution, nonhydrostatic model free of convective parameterization, and describe the effect on the global climate of very that the huge scale separation creates for numerical climate modeling might be safely removed by effectivelyResolving Convection in a Global Hypohydrostatic Model by S. T. Garner1 , D. M. W. Frierson2 , I. M

  13. 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 defines (T \\Gammaae) profile of the adiabatic convection zone, but together with surface conditions of the helium ionization zone (with type of EOS as labels). Filled square with a vertical error bar

  14. Aerosol control on depth of warm rain in convective clouds Mahen Konwar,1

    E-Print Network [OSTI]

    Daniel, Rosenfeld

    Aerosol control on depth of warm rain in convective clouds Mahen Konwar,1 R. S. Maheskumar,1 J. R effective radius (re) increased with distance above cloud base (D). Warm rain became detectable, i.e., rain water content >0.01 g/Kg, at the tops of growing convective clouds when re exceeded 12 mm. The re

  15. 8D.3 INVESTIGATING CONVECTIVE ELEMENTS IN A HIGH RESOLUTION SIMULATION OF HURRICANE OPAL (1995)

    E-Print Network [OSTI]

    Wilhelmson, Robert

    1995-01-01

    8D.3 INVESTIGATING CONVECTIVE ELEMENTS IN A HIGH RESOLUTION SIMULATION OF HURRICANE OPAL (1995. INTRODUCTION Numerous studies have investigated the intensity and track of Hurricane Opal in 1995, an event the convective scale behavior of the hurricane. This is of particular interest because Hurricane Opal

  16. 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

  17. The effect of increased convective entrainment on Asian monsoon biases in

    E-Print Network [OSTI]

    Wirosoetisno, Djoko

    The effect of increased convective entrainment on Asian monsoon biases in the MetUM General entrainment on Asian monsoon biases in the MetUM General Circulation Model. Quarterly Journal of the Royal Reading's research outputs online #12;AcceptedArticle The effect of increased convective entrainment

  18. 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

  19. Numerical model of mixed convection heat transfer between a series of vertical parallel plates with planar heat sources 

    E-Print Network [OSTI]

    Watson, James Christopher

    1995-01-01

    generating surfaces was accomplished by laminar mixed convection, in which forced and free convection effects were considered, and conjugate conduction through the plate. The forced flow at the channel inlet was assumed to be that of an upward flowing...

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

    E-Print Network [OSTI]

    Snyder, Bruce Alan

    1985-01-01

    THE DIVERGENT WIND COMPONENT IN DATA SPARSE TROPICAL WIND FIELDS A Thesis by BRUCE ALAN SNYDER Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE December... 1985 Major Subject: Meteorology THE DIVERGENT WIND COMPONENT IN DATA SPARSE TROPICAL WIND FIELDS A Thesis by BRUCE ALAN SNYDER Approved as to style and content by: James P. McGuirk (Co-Chairman) Aylmer IL Thompson (Co-Chairman) W. Homer...

  1. Measurements of ionospheric electric field convection by the long-line technique

    SciTech Connect (OSTI)

    MacDougall, J.W.

    1981-06-01

    Ionospheric E x B convections are measured by a new technique that uses satellite scintillations. The measurements are for and ionospheric region centred on 39/sup 0/N, 82/sup 0/W geographic or 53/sup 0/ invarient latitude. Results are presented for spring equinox 1980. The quiet condition eastward convection drift is approximately V/sub i/E = -12+43 cos(2..pi../24)(t-13.4). During disturbed conditions at nighttime the westward convection becomes large and highly variable. The northward perpendicular E x B convection is approximately V/sub i/N = -5+13 cos (2..pi../12)(t-10.5)+6 cos (2..pi../24) (t-11.5) m/s during quiet conditions. During disturbed conditions the semidiurnal component of the northward convection increases by about a factor of 3 and becomes larger than the diurnal.

  2. 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

  3. 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

  4. 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

  5. Multivariate Data Assimilation in the Tropics by Using Equatorial Waves NEDJELJKA ZAGAR

    E-Print Network [OSTI]

    Zagar, Nedjeljka

    Multivariate Data Assimilation in the Tropics by Using Equatorial Waves NEDJELJKA ZAGAR 1 multivariate assimila- tion methodology. This applies to both dry and moist idealized tropical systems as well as to a 4D-Var NWP assimilation system. Key words: Tropics, Data assimilation, 4D-Var, Multivariate

  6. Estimating recharge thresholds in tropical karst island aquifers: Barbados, Puerto Rico and Guam

    E-Print Network [OSTI]

    Banner, Jay L.

    Estimating recharge thresholds in tropical karst island aquifers: Barbados, Puerto Rico and Guam in tropical island aquifers, such as Barbados, Guam and Puerto Rico, are significantly influenced by tropical of rainfall. The karst aquifers on Barbados, Guam and Puerto Rico have similar rainwater and groundwater

  7. 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

  8. 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

  9. 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

  10. Recent widening of the tropical belt from global tropopause statistics: Sensitivities

    E-Print Network [OSTI]

    Birner, Thomas

    Recent widening of the tropical belt from global tropopause statistics: Sensitivities Thomas Birner 2010. [1] Several recent studies have shown evidence for a widening of the tropical belt over the past of the resulting widening trend of the tropical belt to these thresholds is investigated using four different

  11. An Experimental Study of Enhanced Thermal Conductivity Utilizing Columnated Silicon Microevaporators for Convective Boiling Heat Transfer at the Microscale

    E-Print Network [OSTI]

    Hogue, Christopher William

    2011-01-01

    topic, and researchers all over the world began reworking classical convection correlations to better model heat transfer

  12. A Family of Fourth Order Difference Schemes on Rotated Grid for Two Dimensional ConvectionDiffusion Equation \\Lambda

    E-Print Network [OSTI]

    Zhang, Jun

    A Family of Fourth Order Difference Schemes on Rotated Grid for Two Dimensional Convection a family of fourth order finite difference schemes on the rotated grid for the two dimensional convection values of the convection coefficients. We also compare the fourth order schemes with the nine point

  13. OPTIMAL CONTROL OF THERMALLY CONVECTED FLUID FLOWS \\Lambda K. ITO y AND S.S. RAVINDRAN y

    E-Print Network [OSTI]

    OPTIMAL CONTROL OF THERMALLY CONVECTED FLUID FLOWS \\Lambda K. ITO y AND S.S. RAVINDRAN y Abstract. We examine the optimal control of stationary thermally convected fluid flows from the the­ oretical and numerical point of view. We use thermal convection as control mechanism, that is, control is effected

  14. 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

  15. Wind reversals in turbulent Rayleigh-Benard convection

    E-Print Network [OSTI]

    Francisco Fontenele Araujo; S. Grossmann; D. Lohse

    2005-08-29

    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 / (\

  16. The structure and dynamics of patterns of Benard convection cells

    SciTech Connect (OSTI)

    Rivier, N. Imperial Coll. of Science and Technology, London . Blackett Lab. Lausanne Univ. . Inst. de Physique Experimentale)

    1990-08-01

    Benard-Marangoni convection, in containers with large aspect ratio, exhibits space-filling cellular structures, highly deformable, but crystallized. They contain dislocations and grain boundaries generated and moved by elementary topological transformations, and are subjected to a weak shear stress due to the earth's rotation. The cellular structure and its fluctuations are analyzed from a crystallographic viewpoint, by using two complementary approaches. One is a global analysis of cellular structures in cylindrical symmetry. Their structural stability and defect pattern are obtained as topological mode-locking of a continuous structural parameter. The other, a local, molecular dynamics of the cells, gives a realistic parametrization of the forces and the transformations by generalizing the Voronoi cell construction in one extra dimension. 23 refs., 8 figs.

  17. Simultaneous temperature and velocity Lagrangian measurements in turbulent thermal convection

    E-Print Network [OSTI]

    Liot, O; Zonta, F; Chibbaro, S; Coudarchet, T; Gasteuil, Y; Pinton, J -F; Salort, J; Chillà, F

    2015-01-01

    We report joint Lagrangian velocity and temperature measurements in turbulent thermal convection. Measurements are performed using an improved version (extended autonomy) of the neutrally-buoyant instrumented particle that was used by to performed experiments in a parallelepipedic Rayleigh-Benard cell. The temperature signal is obtained from a RFtransmitter. Simultaneously, we determine particle's position and velocity with one camera, which grants access to the Lagrangian heat flux. Due to the extended autonomy of the present particle, we obtain well converged temperature and velocity statistics, as well as pseudo-eulerian maps of velocity and heat flux. Present experimental results have also been compared with the results obtained by a corresponding campaign of Direct Numerical Simulations and Lagrangian Tracking of massless tracers. The comparison between experimental and numerical results show the accuracy and reliability of our experimental measurements. Finally, the analysis of lagrangian velocity and t...

  18. Increasing carbon storage in intact African tropical forests

    E-Print Network [OSTI]

    Malhi, Yadvinder

    to predictions of future levels of atmospheric carbon dioxide1,2 . The role of tropical forests is critical dioxide concentrations, may be the cause of the increase in carbon stocks13 , as some theory14 and models2 with estimates of fossil fuel emissions, ocean carbon fluxes and carbon released from land-use change, indicate

  19. WMO/CAS/WWW SEVENTH INTERNATIONAL WORKSHOP ON TROPICAL CYCLONES

    E-Print Network [OSTI]

    Smith, Roger K.

    .smith@lmu.de Working Group Members: Zhuo Wang (Univ. Illinois, USA), David Raymond (New Mexico Tech., New Mexico, USA (i.e. thunderstorm activity) and a definite cyclonic surface wind circulation (Holland 1993)." Notably, this definition does not invoke any wind threshold. The same glossary defines a tropical

  20. Reduction of tropical land region precipitation variability via transpiration

    E-Print Network [OSTI]

    Gentine, Pierre

    plants through open stomata: this process (transpiration) cools the plant and facilitates transportReduction of tropical land region precipitation variability via transpiration Jung-Eun Lee,1 in observations and models. In the present study, the potential role of transpiration for this difference

  1. In Situ Survival of Genetically Engineered Microorganisms in a Tropical

    E-Print Network [OSTI]

    Hazen, Terry

    . Alvarez, G. M. Yumet, and C. L. Santiago Department of Biology, P.O. Box 23360, University of Puerto Rico, Rio Piedras, Puerto Rico 00931-3360 T. C. Hazen Savannah River Laboratory, Environmental Sciences microorganisms (GEMs) and their interactions with the environmental microbiota of a tropical river

  2. MET 416: TROPICAL ANALYSIS AND FORECASTING Spring Semester 2013

    E-Print Network [OSTI]

    current (nowcasting) and expected weather, using all available real-time operational weather data Exam 4/9 Summer trade-wind weather based on HaRP 4/11-16 Large-scale influences, Diurnal cycle to the development of tropical storm systems and mesoscale weather. Lectures will include a forecasting perspective

  3. Hybrid coupled models of the tropical Pacific: I interannual variability

    E-Print Network [OSTI]

    Tang, Youmin

    Y. Tang Hybrid coupled models of the tropical Pacific: I interannual variability Received: 20 Two hybrid coupled models (HCMs), an intermediate complexity dynamical ocean model cou- pled to either), hybrid models (e.g., Barnett et al. 1993; Balmaseda et al. 1994,1995), and fully coupled general

  4. Tropical Pacific mid-latitude teleconnections in medieval times

    E-Print Network [OSTI]

    Cobb, Kim

    records from widely distributed regions around the planet, and in many cases is consistent with a cool centennial-scale drought, elevated incidence of wild fire, cool sea surface temperatures (SSTs) along). Proxy records from the tropical Pacific Ocean show contemporaneous changes indicating cool central

  5. Tropical geometry of statistical models Lior Pachter and Bernd Sturmfels

    E-Print Network [OSTI]

    Marcolli, Matilde

    for graphical models in statistical learning theory (5), but it differs from other (more classical) notionsTropical geometry of statistical models Lior Pachter and Bernd Sturmfels Department of Mathematics, University of California, Berkeley, CA 94720 Communicated by Stephen E. Fienberg, Carnegie Mellon University

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

    SciTech Connect (OSTI)

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

    2009-10-15

    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.

  7. Southern Hemisphere Additional Ozonesondes (SHADOZ) 19982000 tropical ozone climatology

    E-Print Network [OSTI]

    Thompson, Anne

    Southern Hemisphere Additional Ozonesondes (SHADOZ) 1998­2000 tropical ozone climatology 1. Comparison with Total Ozone Mapping Spectrometer (TOMS) and ground-based measurements Anne M. Thompson,1 Additional Ozonesondes (SHADOZ) project and established from operational sites, provided over 1000 ozone

  8. Geochronology of Quaternary glaciations from the tropical Cordillera Huayhuash, Peru

    E-Print Network [OSTI]

    Mark, Bryan G.

    Geochronology of Quaternary glaciations from the tropical Cordillera Huayhuash, Peru Sarah R. Hall to peaks >4800 m a.s.l. Geomorphology and geochronology in the nearby Cordillera Blanca and Junin Plain et al., 2005a, b) and thus completes a north-south glacial geochronologic transect spanning w1

  9. AGCM Precipitation Biases in the Tropical Atlantic M. BIASUTTI

    E-Print Network [OSTI]

    Biasutti, Michela

    AGCM Precipitation Biases in the Tropical Atlantic M. BIASUTTI Lamont-Doherty Earth Observatory precipitation in the Southern Hemisphere in boreal spring and in the Caribbean region in boreal summer precipitation maximum does not occur there. This is the case even though these GCMs accurately place the maximum

  10. US-VISIT Identity Matching Algorithm Evaluation Program: ADIS Algorithm Evaluation Project Plan Update

    SciTech Connect (OSTI)

    Grant, C W; Lenderman, J S; Gansemer, J D

    2011-02-24

    This document is an update to the 'ADIS Algorithm Evaluation Project Plan' specified in the Statement of Work for the US-VISIT Identity Matching Algorithm Evaluation Program, as deliverable II.D.1. The original plan was delivered in August 2010. This document modifies the plan to reflect modified deliverables reflecting delays in obtaining a database refresh. This document describes the revised schedule of the program deliverables. The detailed description of the processes used, the statistical analysis processes and the results of the statistical analysis will be described fully in the program deliverables. The US-VISIT Identity Matching Algorithm Evaluation Program is work performed by Lawrence Livermore National Laboratory (LLNL) under IAA HSHQVT-07-X-00002 P00004 from the Department of Homeland Security (DHS).

  11. 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

  12. Visit CD

    ScienceCinema (OSTI)

    None

    2011-04-25

    Le DG H.Schopper souhaite la bienvenue aux ambassadeurs des pays membres et aux représentants des pays avec lesquels le Cern entretient des relations proches et fait un exposé sur les activités au Cern

  13. 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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking WithTelecentricN A CountyFeet) Cooley Policies

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

    2014-10-27

    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. As a result, 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

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

    SciTech Connect (OSTI)

    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)

    2014-10-27

    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.

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

    E-Print Network [OSTI]

    F. Rincon; F. Lignieres; M. Rieutord

    2006-11-28

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

  17. Motivation for creating the Museum of Scotland, and the educational effectiveness of its history content for the visiting public 

    E-Print Network [OSTI]

    Cramond, Ronald Duncan

    My aim was to investigate the motivation for creating the Museum of Scotland, and the educational effectiveness of its history content for the visiting public,. Part One examines the creation and purpose of the Museum ...

  18. SELF-GUIDED TOUR Thank you for visiting! The University of Rhode Island is truly a special place.

    E-Print Network [OSTI]

    Rhode Island, University of

    visit us again, in person or online at uri.edu. Cynthia L. Bonn Dean of Admission #12 are supported through programs, dining, retail, and support services · Great place to meet friends or get

  19. Modeling Free Convection Flow of Liquid Hydrogen within a Cylindrical Heat Exchanger Cooled to 14 K

    E-Print Network [OSTI]

    Yang, S.W.; Oxford U.

    2004-01-01

    M. A. , “Comments on Liquid Hydrogen Absorbers for MICE,”Gas at 14 to 18 K and Liquid Hydrogen at 20 K circulated byFREE CONVECTION FLOW OF LIQUID HYDROGEN WITHIN A CYLINDRICAL

  20. Characteristics of convective cells over the coastal regions of southeast Texas 

    E-Print Network [OSTI]

    Robinson, Michael

    1998-01-01

    Vertical profiles of radar reflectivity and cloud-to-ground lightning characteristics associated with convective cells were analyzed for mesoscate systems occurring over the coastal regions of southeast Texas during the ...

  1. Turbulent convection in the anelastic rotating sphere : a model for the circulation on the giant planets

    E-Print Network [OSTI]

    Kaspi, Yohai

    2008-01-01

    This thesis studies the dynamics of a rotating compressible gas sphere, driven by internal convection, as a model for the dynamics on the giant planets. We develop a new general circulation model for the Jovian atmosphere, ...

  2. A case study of the low-level jet during an episode of spring convection 

    E-Print Network [OSTI]

    Donahoe, Christopher Scott

    1996-01-01

    Circulation and transport of the low-level jet (LLJ) were examined for a case of severe convection that occurred in Spring 1995. Radiosonde observations and Eta model output on constant pressure and isentropic surfaces allowed a detailed examination...

  3. The feasibility of thermal and compositional convection in Earth’s inner core

    E-Print Network [OSTI]

    Lythgoe, Karen H.; Rudge, John F.; Neufeld, Jerome A.; Deuss, Arwen

    2015-03-12

    of a large core thermal conductivity result in stable thermal stratification, hindering convection. However, an unstable density stratification may arise due to the pressure dependant partition coefficient of certain light elements. We show...

  4. Experimental Investigation of Forced Convection Heat Transfer of Nanofluids in a Microchannel using Temperature Nanosensors 

    E-Print Network [OSTI]

    Yu, Jiwon 1982-

    2012-12-03

    of convective heat transfer involving suspensions of nanoparticles in coolants (or nanofluids). Flow visualization and quantitative estimation of near-wall temperature profiles were performed using quantum dots and fluorescent dyes. This non-contact measurement...

  5. A Summary of Convective-Core Vertical Velocity Properties Using ARM UHF Wind Profilers in Oklahoma

    E-Print Network [OSTI]

    Ohta, Shigemi

    A Summary of Convective-Core Vertical Velocity Properties Using ARM UHF Wind Profilers in Oklahoma Sciences Division, Argonne National Laboratory, Argonne, Illinois # University of Oklahoma, Norman, Oklahoma @ Bureau of Meteorology, Melbourne, Victoria, Australia & Cooperative Institute for Research

  6. Convective Heat Transfer Enhancement in Nanofluids: Real Anomaly or Analysis Artifact?

    E-Print Network [OSTI]

    Prabhat, Naveen

    The nanofluid literature contains many claims of anomalous convective heat transfer enhancement in both turbulent and laminar flow. To put such claims to the test, we have performed a critical detailed analysis of the ...

  7. Convective cloud and rainfall processes over the Maritime Continent : simulation and analysis of the diurnal cycle

    E-Print Network [OSTI]

    Gianotti, Rebecca L. (Rebecca Louise)

    2013-01-01

    The Maritime Continent experiences strong moist convection, which produces significant rainfall and drives large fluxes of heat and moisture to the upper troposphere. Despite the importance of these processes to global ...

  8. HYDRODYNAMIC SIMULATIONS OF H ENTRAINMENT AT THE TOP OF He-SHELL FLASH CONVECTION

    SciTech Connect (OSTI)

    Woodward, Paul R.; Lin, Pei-Hung; Herwig, Falk E-mail: fherwig@uvic.ca

    2015-01-01

    We present the first three-dimensional, fully compressible gas-dynamics simulations in 4? geometry of He-shell flash convection with proton-rich fuel entrainment at the upper boundary. This work is motivated by the insufficiently understood observed consequences of the H-ingestion flash in post-asymptotic giant branch (post-AGB) stars (Sakurai's object) and metal-poor AGB stars. Our investigation is focused on the entrainment process at the top convection boundary and on the subsequent advection of H-rich material into deeper layers, and we therefore ignore the burning of the proton-rich fuel in this study. We find that for our deep convection zone, coherent convective motions of near global scale appear to dominate the flow. At the top boundary convective shear flows are stable against Kelvin-Helmholtz instabilities. However, such shear instabilities are induced by the boundary-layer separation in large-scale, opposing flows. This links the global nature of thick shell convection with the entrainment process. We establish the quantitative dependence of the entrainment rate on grid resolution. With our numerical technique, simulations with 1024{sup 3} cells or more are required to reach a numerical fidelity appropriate for this problem. However, only the result from the 1536{sup 3} simulation provides a clear indication that we approach convergence with regard to the entrainment rate. Our results demonstrate that our method, which is described in detail, can provide quantitative results related to entrainment and convective boundary mixing in deep stellar interior environments with very stiff convective boundaries. For the representative case we study in detail, we find an entrainment rate of 4.38 ± 1.48 × 10{sup –13} M {sub ?} s{sup –1}.

  9. Numerical simualtion of mixed convection over a three-dimensional horizontal backward-facing step 

    E-Print Network [OSTI]

    Barbosa Saldana, Juan Gabriel

    2005-08-29

    -1 NUMERICAL SIMULATION OF MIXED CONVECTION OVER A THREE-DIMENSIONAL HORIZONTAL BACKWARD-FACING STEP A Dissertation by JUAN GABRIEL BARBOSA SALDANA Submitted to the Office of Graduate Studies of Texas A&M University... ? 2005 JUAN GABRIEL BARBOSA SALDANA ALL RIGHTS RESERVED NUMERICAL SIMULATION OF MIXED CONVECTION OVER A THREE-DIMENSIONAL HORIZONTAL BACKWARD-FACING STEP A Dissertation by JUAN GABRIEL BARBOSA SALDANA Submitted to Texas A...

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

    E-Print Network [OSTI]

    Hovis, Jeffrey Scott

    1988-01-01

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

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

    E-Print Network [OSTI]

    Humbert, Mark Edward

    1980-01-01

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

  12. Mixed convection heat transfer from thermal sources mounted on horizontal and vertical surfaces

    SciTech Connect (OSTI)

    Tewari, S.S.; Jaluria, Y. )

    1990-11-01

    An experimental study is carried out on the fundamental aspects of the conjugate, mixed convective heat transfer from two finite width heat sources, which are of negligible thickness, have a uniform heat flux input at the surface, and are located on a flat plate in a horizontal or the vertical orientation. The heat sources are wide in the transverse direction and, therefore, a two-dimensional flow circumstance is simulated. The mixed convection parameter is varied over a fairly wide range to include the buoyancy-dominated and the mixed convection regimes. The circumstances of pure natural convection are also investigated. The convective mechanisms have been studied in detail by measuring the surface temperatures and determining the heat transfer coefficients for the two heated strips, which represent isolated thermal sources. Experimental results indicate that a stronger upstream heat source causes an increase in the surface temperature of a relatively weaker heat source, located downstream, by reducing it convective heat transfer coefficient. The influence of the upstream source is found to be strongly dependent on the surface orientation, especially in the pure natural convection and the buoyancy dominated regimes. The two heat sources are found to be essentially independent on the surface orientation, especially in the pure natural convection and the buoyancy dominated regimes. The two heat sources are found to be essentially independent of each other, in terms of thermal effects, at a separation distance of more than about three strip widths for both the orientations. The results obtained are relevant to many engineering applications, such as the cooling of electronic systems, positioning of heating elements in furnaces, and safety considerations in enclosure fires.

  13. This article is protected by copyright. All rights reserved Representation of daytime moist convection over the semi-arid Tropics by

    E-Print Network [OSTI]

    Guichard, Francoise

    -eddy simulation (LES), Single Column Model (SCM) versions of four different Earth System Models that participated

  14. Convection during the Late Stages of Simmering in Type Ia Supernovae

    E-Print Network [OSTI]

    Piro, Anthony L

    2008-01-01

    Following unstable ignition of carbon, but prior to explosion, a white dwarf (WD) in a Type Ia supernova (SN Ia) undergoes a simmering phase. During this time, a central convective region grows and encompasses ~1 Msun of the WD over a timescale of ~1000 yrs, which sets the thermal and turbulent profile for the subsequent explosion. We study this time-dependent convection and summarize some of the key features that differ from the traditional, steady-state case. We show that the long conductive timescale above the convective zone and the extraction of energy to heat the WD core leads to a decrease of the convective luminosity and characteristic velocities near the convective zone's top boundary. In addition, differences in the composition between the convective core and the conductive exterior will significantly alter the location of this boundary. In this respect, we find the biggest effect due to complete 22Ne sedimentation prior to carbon ignition. These effects add diversity to the possible WD models, whic...

  15. Convection during the Late Stages of Simmering in Type Ia Supernovae

    E-Print Network [OSTI]

    Anthony L. Piro; Philip Chang

    2008-01-08

    Following unstable ignition of carbon, but prior to explosion, a white dwarf (WD) in a Type Ia supernova (SN Ia) undergoes a simmering phase. During this time, a central convective region grows and encompasses ~1 Msun of the WD over a timescale of ~1000 yrs, which sets the thermal and turbulent profile for the subsequent explosion. We study this time-dependent convection and summarize some of the key features that differ from the traditional, steady-state case. We show that the long conductive timescale above the convective zone and the extraction of energy to heat the WD core leads to a decrease of the convective luminosity and characteristic velocities near the convective zone's top boundary. In addition, differences in the composition between the convective core and the conductive exterior will significantly alter the location of this boundary. In this respect, we find the biggest effect due to complete 22Ne sedimentation prior to carbon ignition. These effects add diversity to the possible WD models, which may alter the properties of the SN Ia explosion.

  16. Film condensation of saturated and superheated vapors along isothermal vertical surfaces in mixed convection

    SciTech Connect (OSTI)

    Winkler, C.M.; Chen, T.S.; Minkowycz, W.J.

    1999-09-01

    An analysis for condensation from an isothermal vertical flat plate in mixed convection is reported. The entire mixed convection regime is divided into two regions. One region covers the forced-convection-dominated regime, and the other covers the free-convection-dominated regime. The governing system of equations is first transformed into a dimensionless form by the nonsimilar transformation, separately for each regime, and then solved using the local nonsimilarity method along with a finite difference scheme. Two nonsimilarity parameters are introduced. The parameter {xi}{sub f} = Gr{sub x}/Re{sub x}{sup 2} characterizes the effect of buoyancy force on forced convection, while the parameter {xi}{sub n} = Re{sub x}/Gr{sub x}{sup 1/2} characterizes the effect of forced flow on free convection. Numerical results for pure steam and refrigerant R-134a are presented for both saturated and superheated cases. It is found that the buoyancy force significantly increases the wall shear stress and condensate mass flux. To a lesser degree, the buoyancy force also increases the wall heat flux. Superheating is found to have an insignificant effect on wall heat flux for a pure vapor.

  17. NIS codes: OS = new/renewal on-site visit PT = proficiency testing on-site FOLUP = follow-up assessment MV = monitoring visit PRE = pre-assessment MOVE = on-site after lab move ADDTM = on-site to assess additions to scope

    E-Print Network [OSTI]

    NIS codes: OS = new/renewal on-site visit PT = proficiency testing on-site FOLUP = follow nonconformities only) #12;NIS codes: OS = new/renewal on-site visit PT = proficiency testing on-site FOLUP

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

    E-Print Network [OSTI]

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

    2015-01-01

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

  19. Radial convection of finite ion temperature, high amplitude plasma blobs

    SciTech Connect (OSTI)

    Wiesenberger, M. Kendl, A.; Madsen, J.

    2014-09-15

    We present results from simulations of seeded blob convection in the scrape-off-layer of magnetically confined fusion plasmas. We consistently incorporate high fluctuation amplitude levels and finite Larmor radius (FLR) effects using a fully nonlinear global gyrofluid model. This is in line with conditions found in tokamak scrape-off-layers (SOL) regions. Varying the ion temperature, the initial blob width, and the initial amplitude, we found an FLR dominated regime where the blob behavior is significantly different from what is predicted by cold-ion models. The transition to this regime is very well described by the ratio of the ion gyroradius to the characteristic gradient scale length of the blob. We compare the global gyrofluid model with a partly linearized local model. For low ion temperatures, we find that simulations of the global model show more coherent blobs with an increased cross-field transport compared to blobs simulated with the local model. The maximal blob amplitude is significantly higher in the global simulations than in the local ones. When the ion temperature is comparable to the electron temperature, global blob simulations show a reduced blob coherence and a decreased cross-field transport in comparison with local blob simulations.

  20. Optimal Heat Transport in Rayleigh-B\\'enard Convection

    E-Print Network [OSTI]

    Sondak, David; Waleffe, Fabian

    2015-01-01

    Steady flows that optimize heat transport are obtained for two-dimensional Rayleigh-B\\'enard convection with no-slip horizontal walls for a variety of Prandtl numbers $Pr$ and Rayleigh number up to $Ra\\sim 10^9$. Power law scalings of $Nu\\sim Ra^{\\gamma}$ are observed with $\\gamma\\approx 0.31$, where the Nusselt number $Nu$ is a non-dimensional measure of the vertical heat transport. Any dependence of the scaling exponent on $Pr$ is found to be extremely weak. On the other hand, the presence of two local maxima of $Nu$ with different horizontal wavenumbers at the same $Ra$ leads to the emergence of two different flow structures as candidates for optimizing the heat transport. For $Pr \\lesssim 7$, optimal transport is achieved at the smaller maximal wavenumber. In these fluids, the optimal structure is a plume of warm rising fluid which spawns left/right horizontal arms near the top of the channel, leading to downdrafts adjacent to the central updraft. For $Pr > 7$ at high-enough Ra, the optimal structure is a...