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


1

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

E-Print Network [OSTI]

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

McGaughey, Gary Rae

1994-01-01T23:59:59.000Z

2

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

SciTech Connect (OSTI)

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.

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

2013-08-01T23:59:59.000Z

3

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

SciTech Connect (OSTI)

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.

Schumacher, Courtney

2012-12-13T23:59:59.000Z

4

Impact of Convective Organization on the Response of Tropical Precipitation Extremes to Warming  

E-Print Network [OSTI]

Impact of Convective Organization on the Response of Tropical Precipitation Extremes to Warming extremes to warming in organized convection is ex- amined using a cloud-resolving model. Vertical shear, the fractional increase of precipitation extremes is similar to that of surface water vapor, which

Paris-Sud XI, Université de

5

A numerical study of mesoscale convection in a rotating tropical atmosphere  

E-Print Network [OSTI]

similar to the profile of a tropical disturbance. The meso-p forcing of convection consisted of' seven temperature perturbations con- fined below 2. 4 km at intervals of 8 km out to 60 km. The meso-9 forcing of convection comprised of a cosine thermal... perturbation field out to 75 km. Two different classes of simulations were performed. The first part explored how background vorticity affects convection generated by meso-7 and meso-9 forcing. The second part investigated how meso-9 forcing of convection...

Fitzpatrick, Patrick James

1992-01-01T23:59:59.000Z

6

Influence of Sea Surface Temperature on Humidity and Temperature in the Outflow of Tropical Deep Convection  

E-Print Network [OSTI]

-Service Aircraft (MOZAIC) project are analyzed in the vicinity of deep convective outflow to study the variationsInfluence of Sea Surface Temperature on Humidity and Temperature in the Outflow of Tropical Deep upper-tropospheric temperature and humidity by the Mea- surement of Ozone and Water Vapor by Airbus In

Johnson, Richard H.

7

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

E-Print Network [OSTI]

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

Hartmann, Dennis

8

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

SciTech Connect (OSTI)

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.

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

2014-10-15T23:59:59.000Z

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcal Documentation(AVIRIS) ProductsAirborneOctober 11, 2011 [Facility News]JanuarygovCampaignsYear of Tropical

10

Overshooting Convection from High-resolution NEXRAD Observations  

E-Print Network [OSTI]

employs the difference between 6-7 Ķm water vapor absorption and ?11 Ķm infrared window channel brightness temper- ature for overshooting convection detection (e.g., Fritz and Laszlo, 1993; Ackerman, 2 1996; Schmetz et al., 1997; Setvak et al., 2007... and in Radiative Forcing, pp. 129Ė234, Cambridge University Press, Cambridge, UK. Fritz, S., and I. Laszlo (1993), Detection of water vapor in the stratosphere over very high clouds in the tropics, J. Geophys. Res., 98 (D12), 22,959Ė22,967. 32 Fromm, M. D., and R...

Solomon, David

2014-01-09T23:59:59.000Z

11

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

E-Print Network [OSTI]

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

Devlin, Karen Irene

1995-01-01T23:59:59.000Z

12

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

E-Print Network [OSTI]

October 1986 R. H. Johnson 721 Lower-Tropospheric Warming and Drying in Tropical Mesoscale Convective Systems: Implications for the Problem of Cumulus Parameterization By Richard H. Johnson Department beneath the stratiform com- ponents of these systems (Houze, 1977; Zipser, 1977; Johnson and Kriete, 1982

Johnson, Richard H.

13

RETRIEVAL OF HYDROMETEOR PROFILES IN TROPICAL CYCLONES AND CONVECTION BY A COMBINED  

E-Print Network [OSTI]

to simulate the ice phase radiative transfer process more reasonably. Final optimal 's as well as the observed a significant influence on the energy and water budgets. The latent heat release in tropical cyclones provides of the circulation of the storm. Directly related to latent heating, ice water content (IWC) and liq

Jiang, Haiyan

14

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 - SeptemberMicroneedles for4-16HamadaBaO/Al2O3 lean NOx trapProofreadingProperties

15

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

E-Print Network [OSTI]

), Characteristics of tropical convection over the ocean near Kwajalein, Mon Weather Rev, 134, 834-853. Dessler, A. E., S. P. Palm, and J. D. Spinhirne (2006), Tropical cloud-top height distributions revealed by the Ice, Cloud, and Land Elevation Satellite...

Casey, Sean Patrick

2009-06-02T23:59:59.000Z

16

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

E-Print Network [OSTI]

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

Hernandez, Celina Anne

2009-05-15T23:59:59.000Z

17

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

E-Print Network [OSTI]

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

Houze Jr., Robert A.

18

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

E-Print Network [OSTI]

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

Houze Jr., Robert A.

19

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

E-Print Network [OSTI]

of the radar beam for the NCAR CP-3 and CP-4 Doppler radars and the NOAA/TOGA Doppler radar as a function of beamwidth 3 Maximum ref lectivity at selected heights and the range to the closest radar, at 4. 4 km, for the convective cells from the 10-11 June... Maximum ref lectivity at selected heights and the range to the NOAA/TOGA Doppler radar, at 3. 9 km, for the convective cells from the 2 December 1988 monsoon case 21 21 51 56 63 70 76 Table 8 As in Table 7, except for the convective cells from...

Lutz, Kurt Reed

1992-01-01T23:59:59.000Z

20

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

SciTech Connect (OSTI)

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

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

2013-07-16T23:59:59.000Z

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


21

Equilibrium Tropical Cyclone Size in an Idealized State of Axisymmetric RadiativeĖConvective Equilibrium*  

E-Print Network [OSTI]

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 ...

Chavas, Daniel R.

22

Improving Convection Parameterization Using ARM Observations and NCAR Community Atmosphere Model  

SciTech Connect (OSTI)

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.

Zhang, Guang J [Scripps Institution of Oceanography

2013-07-29T23:59:59.000Z

23

Identifying the top of the tropical tropopause layer from vertical mass flux analysis and CALIPSO lidar cloud observations  

E-Print Network [OSTI]

deep convection from the tropical rainfall measuring mission precipitation radar, Alcala and Dessler defined as the level of zero net radiative heating, which occurs near 14.5­15 km [e.g., Folkins et al convection occurring below this level will sink back to the surface, and air detraining above this level

Hochberg, Michael

24

Total lightning observations of severe convection over North Texas  

E-Print Network [OSTI]

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

McKinney, Christopher Michael

2009-05-15T23:59:59.000Z

25

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation Proposed New SubstationCleanCommunity2Workshops01ControllingControls on SolubleConvection in

26

A Test of the Simulation of Tropical Convective Cloudiness by a Cloud-Resolving Model MARIO A. LOPEZ, DENNIS L. HARTMANN, PETER N. BLOSSEY, ROBERT WOOD,  

E-Print Network [OSTI]

un- certainties in projections of future climates (Bony et al. 2006; Solomon et al. 2007). Clouds solar radiation, although their effect on the net energy balance is often much less than with intense tropical convective systems are known to have long lifetimes and to cover large areas, accounting

Hartmann, Dennis

27

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

SciTech Connect (OSTI)

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.

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

2014-05-16T23:59:59.000Z

28

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

E-Print Network [OSTI]

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

Mapes, Brian

29

Characteristics of Precipitating Convective Systems Accounting for the Summer Rainfall of Tropical and Subtropical South America  

E-Print Network [OSTI]

and Subtropical South America ULRIKE ROMATSCHKE AND ROBERT A. HOUZE JR. University of Washington, Seattle of the precipitating cloud systems that account for the summer rainfall of tropical and subtropical South America role in the meteorology, climatology, and hydrology of South America. They not only produce

Houze Jr., Robert A.

30

Intermediate Zonal Jets in the Tropical Pacific Ocean Observed by Argo Floats* SOPHIE CRAVATTE  

E-Print Network [OSTI]

Intermediate Zonal Jets in the Tropical Pacific Ocean Observed by Argo Floats* SOPHIE CRAVATTE¬īveloppement, LEGOS, Toulouse, France WILLIAM S. KESSLER National Oceanic and Atmospheric Administration/Pacific Argo float data in the tropical Pacific Ocean during January 2003¬≠August 2011 are analyzed to obtain

Boyer, Edmond

31

Observed radar reflectivity in convectively coupled Kelvin and mixed Rossby-gravity waves  

E-Print Network [OSTI]

be measurable from surface gauges (>0.5 mm/hr). Addition- ally, the area of radar echo at each height of a normalized probability density function (PDF) of radar echo intensity at that level. Our analysis uses radarObserved radar reflectivity in convectively coupled Kelvin and mixed Rossby-gravity waves A. Swann

Yuter, Sandra

32

Modeling the observed proton aurora and ionospheric convection responses to changes in the IMF clock angle  

E-Print Network [OSTI]

Modeling the observed proton aurora and ionospheric convection responses to changes in the IMF clock angle: 1. Persistence of cusp proton aurora K. Throp, M. Lockwood,1 B. S. Lanchester, and S. K employ a numerical model of cusp ion precipitation and proton aurora emission to fit variations

Lockwood, Mike

33

Reverse convection and cusp proton aurora: Cluster, polar and image observation  

E-Print Network [OSTI]

Reverse convection and cusp proton aurora: Cluster, polar and image observation Q.-G. Zong a,b,*, TT) at Earth. Cusp proton aurora was caused by the leading phase of the CME. Cusp proton aurora generally of the cusp proton aurora shifted about 30į from dawnside to duskside when IMF By changed from ņ10 to 5 n

California at Berkeley, University of

34

GRANULATION IN RED GIANTS: OBSERVATIONS BY THE KEPLER MISSION AND THREE-DIMENSIONAL CONVECTION SIMULATIONS  

SciTech Connect (OSTI)

The granulation pattern that we observe on the surface of the Sun is due to hot plasma rising to the photosphere where it cools down and descends back into the interior at the edges of granules. This is the visible manifestation of convection taking place in the outer part of the solar convection zone. Because red giants have deeper convection zones than the Sun, we cannot a priori assume that their granulation is a scaled version of solar granulation. Until now, neither observations nor one-dimensional analytical convection models could put constraints on granulation in red giants. With asteroseismology, this study can now be performed. We analyze {approx}1000 red giants that have been observed by Kepler during 13 months. We fit the power spectra with Harvey-like profiles to retrieve the characteristics of the granulation (timescale {tau}{sub gran} and power P{sub gran}). We search for a correlation between these parameters and the global acoustic-mode parameter (the position of maximum power, {nu}{sub max}) as well as with stellar parameters (mass, radius, surface gravity (log g), and effective temperature (T{sub eff})). We show that {tau}{sub eff}{proportional_to}{nu}{sup -0.89}{sub max} and P{sub gran}{proportional_to}{nu}{sup -1.90}{sub max}, which is consistent with the theoretical predictions. We find that the granulation timescales of stars that belong to the red clump have similar values while the timescales of stars in the red giant branch are spread in a wider range. Finally, we show that realistic three-dimensional simulations of the surface convection in stars, spanning the (T{sub eff}, log g) range of our sample of red giants, match the Kepler observations well in terms of trends.

Mathur, S. [High Altitude Observatory, NCAR, P.O. Box 3000, Boulder, CO 80307 (United States); Hekker, S. [Astronomical Institute 'Anton Pannekoek', University of Amsterdam, P.O. Box 94249, 1090 GE Amsterdam (Netherlands); Trampedach, R. [JILA, University of Colorado and National Institute of Standards and Technology, 440 UCB, Boulder, CO 80309 (United States); Ballot, J. [Institut de Recherche en Astrophysique et Planetologie, CNRS, 14 avenue E. Belin, 31400 Toulouse (France); Kallinger, T. [Institute for Astronomy (IfA), University of Vienna, Tuerkenschanzstrasse 17, 1180 Vienna (Austria); Buzasi, D. [Eureka Scientific, 2452 Delmer Street Suite 100, Oakland, CA 94602-3017 (United States); Garcia, R. A. [Laboratoire AIM, CEA/DSM-CNRS-Universite Paris Diderot-IRFU/SAp, 91191 Gif-sur-Yvette Cedex (France); Huber, D.; Bedding, T. R.; Stello, D. [Sydney Institute for Astronomy, School of Physics, University of Sydney, NSW 2006 (Australia); Jimenez, A.; Regulo, C. [Dpto de Astrofisica, Universidad de La Laguna, 38206, Tenerife (Spain); Mosser, B. [LESIA, UMR8109, Universite Pierre et Marie Curie, Universite Denis Diderot, Obs. de Paris, 92195 Meudon Cedex (France); Elsworth, Y.; Chaplin, W. J.; Hale, S. J. [School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); De Ridder, J. [Instituut voor Sterrenkunde, K.U. Leuven, Celestijnenlaan 200D, 3001 Leuven (Belgium); Kinemuchi, K. [Bay Area Environmental Research Inst./NASA Ames Research Center, Moffett Field, CA 94035 (United States); Kjeldsen, H. [Danish AsteroSeismology Centre, Department of Physics and Astronomy, University of Aarhus, 8000 Aarhus C (Denmark); Mullally, F. [SETI Institute/NASA Ames Research Center, Moffett Field, CA 94035 (United States)

2011-11-10T23:59:59.000Z

35

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

E-Print Network [OSTI]

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

Masunaga, Hirohiko

36

Aircraft Observations of Sub-cloud Aerosol and Convective Cloud Physical Properties  

E-Print Network [OSTI]

of Department, Kenneth Bowman December 2009 Major Subject: Atmospheric Sciences iii iii ABSTRACT Aircraft Observations of Sub-Cloud Aerosol and Convective Cloud Physical Properties. (December 2009) Duncan Axisa, B.Ed., University of Malta; B... but for vertical velocity (ms-1). Negative values are updraft and positive values are downdraft ........................................... 30 18 Cloud droplet size distribution (dN/dlogD, cm-3) for 1Hz cloud penetration data...

Axisa, Duncan

2011-02-22T23:59:59.000Z

37

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

SciTech Connect (OSTI)

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.

Niyogi, Devdutta S. [Purdue

2013-06-07T23:59:59.000Z

38

Quarterly Journal of the Royal Meteorological Society Q. J. R. Meteorol. Soc. (2013) Phenomenology of Sahelian convection observed in Niamey  

E-Print Network [OSTI]

Quarterly Journal of the Royal Meteorological Society Q. J. R. Meteorol. Soc. (2013) Phenomenology SM. 2013. Phenomenology of Sahelian convection observed in Niamey during the early monsoon. Q. J. R

Guichard, Francoise

39

12.811 Tropical Meteorology, Spring 2005  

E-Print Network [OSTI]

This course describes the behavior and dynamics of the tropical troposphere, from the large-scale energy balance down to cumulus convection and tropical cyclones. Topics include: Radiative-convective equilibrium; the Hadley ...

Emanuel, Kerry

40

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

E-Print Network [OSTI]

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

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

2007-01-01T23:59:59.000Z

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


41

Variability of tropical cyclone track density in the2 North Atlantic: Observations and high-resolution3  

E-Print Network [OSTI]

; Emanuel 2005a)59 and the accumulated cyclone energy (ACE; Bell et al. 2000). Our focus here is on60 1 1 Variability of tropical cyclone track density in the2 North Atlantic: Observations #12; 2 Abstract23 24 Interannual-decadal variability of tropical cyclone (TC) track density

Xie, Shang-Ping

42

Retrieval of Hydrometeor Profiles in Tropical Cyclones and Convection from Combined Radar and Radiometer Observations  

E-Print Network [OSTI]

of understanding the global energy and water cycles by providing four-dimensional distributions of latent heat- ing related to latent heating, ice water content (IWC) and liquid water content (LWC) have implications A retrieval algorithm is described to estimate vertical profiles of precipitation ice water content and liquid

Jiang, Haiyan

43

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

E-Print Network [OSTI]

in Argentina during the Sprite2006 Campaign in Brazil F. T. S√£o 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

Thomas, Jeremy N.

44

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

E-Print Network [OSTI]

AND WILLIAM R. COTTON Department of Atmospheric Science, Colorado State University, Fort Collins, Colorado merge into a large, long-lived organized convective system (Cotton and Anthes 1989). Thus, forecasting

45

Long-term Observations of the Convective Boundary Layer Using Insect Radar Returns at the SGP ARM Climate Research Facility  

SciTech Connect (OSTI)

A long-term study of the turbulent structure of the convective boundary layer (CBL) at the U.S. Department of Energy Atmospheric Radiation Measurement Program (ARM) Southern Great Plains (SGP) Climate Research Facility is presented. Doppler velocity measurements from insects occupying the lowest 2 km of the boundary layer during summer months are used to map the vertical velocity component in the CBL. The observations cover four summer periods (2004-08) and are classified into cloudy and clear boundary layer conditions. Profiles of vertical velocity variance, skewness, and mass flux are estimated to study the daytime evolution of the convective boundary layer during these conditions. A conditional sampling method is applied to the original Doppler velocity dataset to extract coherent vertical velocity structures and to examine plume dimension and contribution to the turbulent transport. Overall, the derived turbulent statistics are consistent with previous aircraft and lidar observations. The observations provide unique insight into the daytime evolution of the convective boundary layer and the role of increased cloudiness in the turbulent budget of the subcloud layer. Coherent structures (plumes-thermals) are found to be responsible for more than 80% of the total turbulent transport resolved by the cloud radar system. The extended dataset is suitable for evaluating boundary layer parameterizations and testing large-eddy simulations (LESs) for a variety of surface and cloud conditions.

Chandra, A S; Kollias, P; Giangrande, S E; Klein, S A

2009-08-20T23:59:59.000Z

46

Quarterly Journal of the Royal Meteorological Society Q. J. R. Meteorol. Soc. 140: 500516, January 2014 B Phenomenology of Sahelian convection observed in Niamey  

E-Print Network [OSTI]

2014 B Phenomenology of Sahelian convection observed in Niamey during the early monsoon C. Dionea Citation: Dione C, Lothon M, Badiane D, Campistron B, Couvreux F, Guichard F, Sall SM. 2014. Phenomenology

Guichard, Francoise

47

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

SciTech Connect (OSTI)

This three-year project, in cooperation with Professor Bob Houze at University of Washington, has been successfully finished as planned. Both ARM (the Atmospheric Radiation Measurement Program) data and cloud-resolving model (CRM) simulations were used to identify the water budgets of clouds observed in two international field campaigns. The research results achieved shed light on several key processes of clouds in climate change (or general circulation models), which are summarized below. 1. Revealed the effect of mineral dust on mesoscale convective systems (MCSs) Two international field campaigns near a desert and a tropical coast provided unique data to drive and evaluate CRM simulations, which are TWP-ICE (the Tropical Warm Pool International Cloud Experiment) and AMMA (the African Monsoon Multidisciplinary Analysis). Studies of the two campaign data were contrasted, revealing that much mineral dust can bring about large MCSs via ice nucleation and clouds. This result was reported as a PI presentation in the 3rd ASR Science Team meeting held in Arlington, Virginia in March 2012. A paper on the studies was published in the Journal of the Atmospheric Sciences (Zeng et al. 2013). 2. Identified the effect of convective downdrafts on ice crystal concentration Using the large-scale forcing data from TWP-ICE, ARM-SGP (the Southern Great Plains) and other field campaigns, Goddard CRM simulations were carried out in comparison with radar and satellite observations. The comparison between model and observations revealed that convective downdrafts could increase ice crystal concentration by up to three or four orders, which is a key to quantitatively represent the indirect effects of ice nuclei, a kind of aerosol, on clouds and radiation in the Tropics. This result was published in the Journal of the Atmospheric Sciences (Zeng et al. 2011) and summarized in the DOE/ASR Research Highlights Summaries (see http://www.arm.gov/science/highlights/RMjY5/view). 3. Used radar observations to evaluate model simulations In cooperation with Profs. Bob Houze at University of Washington and Steven Rutledge at Colorado State University, numerical model results were evaluated with observations from W- and C-band radars and CloudSat/TRMM satellites. These studies exhibited some shortcomings of current numerical models, such as too little of thin anvil clouds, directing the future improvement of cloud microphysics parameterization in CRMs. Two papers of Powell et al (2012) and Zeng et al. (2013), summarizing these studies, were published in the Journal of the Atmospheric Sciences. 4. Analyzed the water budgets of MCSs Using ARM data from TWP-ICE, ARM-SGP and other field campaigns, the Goddard CRM simulations were carried out to analyze the water budgets of clouds from TWP-ICE and AMMA. The simulations generated a set of datasets on clouds and radiation, which are available http://cloud.gsfc.nasa.gov/. The cloud datasets were available for modelers and other researchers aiming to improve the representation of cloud processes in multi-scale modeling frameworks, GCMs and climate models. Special datasets, such as 3D cloud distributions every six minutes for TWP-ICE, were requested and generated for ARM/ASR investigators. Data server records show that 86,206 datasets were downloaded by 120 users between April of 2010 and January of 2012. 5. MMF simulations The Goddard MMF (multi-scale modeling framework) has been improved by coupling with the Goddard Land Information System (LIS) and the Goddard Earth Observing System Model, Version 5 (GOES5). It has also been optimized on NASA HEC supercomputers and can be run over 4000 CPUs. The improved MMF with high horizontal resolution (1 x 1 degree) is currently being applied to cases covering 2005 and 2006. The results show that the spatial distribution pattern of precipitation rate is well simulated by the MMF through comparisons with satellite retrievals from the CMOPRH and GPCP data sets. In addition, the MMF results were compared with three reanalyses (MERRA, ERA-Interim and CFSR). Although the MMF tends

Tao, Wei-Kuo; Houze, Robert, A., Jr.; Zeng, Xiping

2013-03-14T23:59:59.000Z

48

5, 1102911054, 2005 Convective gravity  

E-Print Network [OSTI]

ACPD 5, 11029­11054, 2005 Convective gravity waves at mid-latitudes Y. G. Choi et al. Title Page Discussions Wind-profiler observations of gravity waves produced by convection at mid-latitudes Y. G. Choi1­11054, 2005 Convective gravity waves at mid-latitudes Y. G. Choi et al. Title Page Abstract Introduction

Paris-Sud XI, Université de

49

Observed Regimes of Mid-Latitude.and Tropical Cirrus Microphysical Behavior  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the ContributionsArmsSpeedingSpeedingUnder Well-ControlledObservationObserved Regimes of

50

Observations of new aerosol particle formation in a tropical urban Raghu Betha a  

E-Print Network [OSTI]

-19, Singapore 117576, Singapore b School of Earth and Environment, University of Leeds, Leeds LS2 9JT, United. These nucleation events were frequently observed during the SW monsoon period, but were rarely seen during the NE events were suppressed. √? 2013 Elsevier Ltd. All rights reserved. 1. Introduction Atmospheric aerosols

Spracklen, Dominick

51

Observations of tropical clouds from the upgraded MMCR at Darwin and  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the ContributionsArmsSpeedingSpeedingUnder Well-ControlledObservation ofofEdgecomparisons

52

The Tropical Warm Pool International Cloud Experiment  

SciTech Connect (OSTI)

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.

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

2008-05-01T23:59:59.000Z

53

Observed Characteristics of Clouds and Precipitating Systems Associated with the Tropical Circulation in Global Models and Reanalyses  

E-Print Network [OSTI]

This dissertation presents a series of work related to the representation of the Hadley circulation (HC) in atmospheric reanalyses and general circulation models (GCMs), with connections to the underlying tropical and subtropical cloud systems...

Stachnik, Justin Paul

2013-03-25T23:59:59.000Z

54

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

SciTech Connect (OSTI)

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 Ė 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 Darwinís coastal location, the convection that occurs over and near Darwin at this time is largely of maritime origin with a large fetch over water. Based on previous experiments, the convection appears typical of maritime convection with widespread convection that has complex organization, but is not as deep or as intense as continental or coastal convection. Therefore, it is expected that the convection and cloud characteristics will be representative of conditions typical for wide areas of the tropics.

PT May; C Jakob; JH Mather

2004-05-30T23:59:59.000Z

55

Analysis of tropical radiative heating profiles: A comparison...  

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

tropical radiative heating profiles: A comparison of models and observations . Analysis of tropical radiative heating profiles: A comparison of models and observations . Abstract:...

56

Development of Ensemble Neural Network Convection Parameterizations for Climate Models  

SciTech Connect (OSTI)

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.

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

2012-05-02T23:59:59.000Z

57

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

SciTech Connect (OSTI)

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

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

2010-03-15T23:59:59.000Z

58

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

SciTech Connect (OSTI)

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.

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

2004-05-31T23:59:59.000Z

59

Reactor Engineering: Experimental Investigation of Alpha Convection  

SciTech Connect (OSTI)

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

Usman, Shoaib

2012-10-12T23:59:59.000Z

60

What causes the large extensions of red-supergiant atmospheres? Comparisons of interferometric observations with 1-D hydrostatic, 3-D convection, and 1-D pulsating model atmospheres  

E-Print Network [OSTI]

We present the atmospheric structure and the fundamental parameters of three red supergiants, increasing the sample of RSGs observed by near-infrared spectro-interferometry. Additionally, we test possible mechanisms that may explain the large observed atmospheric extensions of RSGs. We carried out spectro-interferometric observations of 3 RSGs in the near-infrared K-band with the VLTI/AMBER instrument at medium spectral resolution. To comprehend the extended atmospheres, we compared our observational results to predictions by available hydrostatic PHOENIX, available 3-D convection, and new 1-D self-excited pulsation models of RSGs. Our near-infrared flux spectra are well reproduced by the PHOENIX model atmospheres. The continuum visibility values are consistent with a limb-darkened disk as predicted by the PHOENIX models, allowing us to determine the angular diameter and the fundamental parameters of our sources. Nonetheless, in the case of V602 Car and HD 95686, the PHOENIX model visibilities do not predict ...

Arroyo-Torres, B; Chiavassa, A; Scholz, M; Freytag, B; Marcaide, J M; Hauschildt, P H; Wood, P R; Abellan, F J

2015-01-01T23:59:59.000Z

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


61

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

SciTech Connect (OSTI)

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

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

1999-06-01T23:59:59.000Z

62

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

E-Print Network [OSTI]

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

Lintner, Benjamin Richard

63

Convection towers  

DOE Patents [OSTI]

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.

Prueitt, M.L.

1996-01-16T23:59:59.000Z

64

Convection towers  

DOE Patents [OSTI]

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.

Prueitt, Melvin L. (Los Alamos, NM)

1994-01-01T23:59:59.000Z

65

Convection towers  

DOE Patents [OSTI]

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.

Prueitt, Melvin L. (Los Alamos, NM)

1996-01-01T23:59:59.000Z

66

Convection towers  

DOE Patents [OSTI]

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.

Prueitt, Melvin L. (Los Alamos, NM)

1995-01-01T23:59:59.000Z

67

Convection towers  

DOE Patents [OSTI]

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.

Prueitt, M.L.

1994-02-08T23:59:59.000Z

68

Feedbacks in a simple prognostic tropical climate model  

SciTech Connect (OSTI)

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

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

1999-07-01T23:59:59.000Z

69

Different convection models in ATLAS  

E-Print Network [OSTI]

Convection is an important phenomenon in the atmospheres of A-type and cooler stars. A description of convection in ATLAS models is presented, together with details of how it is specified in model calculations. The effects of changing the treatment of convection on model structures and how this affects observable quantities are discussed. The role of microturbulence is examined, and its link to velocity fields within the atmosphere. Far from being free parameters, mixing-length and microturbulence should be constrained in model calculations.

Barry Smalley

2005-09-19T23:59:59.000Z

70

Heat distribution by natural convection  

SciTech Connect (OSTI)

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.

Balcomb, J.D.; Yamaguchi, K.

1983-01-01T23:59:59.000Z

71

Convective heater  

DOE Patents [OSTI]

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.

Thorogood, Robert M. (Macungie, PA)

1986-01-01T23:59:59.000Z

72

Convective heater  

DOE Patents [OSTI]

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

Thorogood, R.M.

1983-12-27T23:59:59.000Z

73

Data assimilation for stratified convection  

E-Print Network [OSTI]

We show how the 3DVAR data assimilation methodology can be used in the astrophysical context of a two-dimensional convection flow. We study the way this variational approach finds best estimates of the current state of the flow from a weighted average of model states and observations. We use numerical simulations to generate synthetic observations of a vertical two-dimensional slice of the outer part of the solar convection zone for varying noise levels and implement 3DVAR when the covariance matrices are scalar. Our simulation results demonstrate the capability of 3DVAR to produce error estimates of system states between up to tree orders of magnitude below the original noise level present in the observations. This work exemplifies the importance of applying data assimilation techniques in simulations of the stratified convection.

Svedin, Andreas; Brandenburg, Axel

2013-01-01T23:59:59.000Z

74

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

SciTech Connect (OSTI)

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

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

2008-11-20T23:59:59.000Z

75

Elastic Convection in Vibrated Viscoplastic Fluids  

E-Print Network [OSTI]

We observe a new type of behavior in a shear thinning yield stress fluid: freestanding convection rolls driven by vertical oscillation. The convection occurs without the constraint of container boundaries yet the diameter of the rolls is spontaneously selected for a wide range of parameters. The transition to the convecting state occurs without hysteresis when the amplitude of the plate acceleration exceeds a critical value. We find that a non-dimensional stress, the stress due to the inertia of the fluid normalized by the yield stress, governs the onset of the convective motion.

Hayato Shiba; Jori Ruppert-Felsot; Yoshiki Takahashi; Yoshihiro Murayama; Qi Ouyang; Masaki Sano

2006-08-07T23:59:59.000Z

76

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

E-Print Network [OSTI]

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

Boyer, Edmond

77

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

SciTech Connect (OSTI)

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

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

2013-11-26T23:59:59.000Z

78

On the Diurnal Cycle of Deep Convection, High-Level Cloud, and Upper Troposphere Water Vapor in the Multiscale Modeling Framework  

SciTech Connect (OSTI)

The Multiscale Modeling Framework (MMF), also called ĎĎsuperparameterizationíí, embeds a cloud-resolving model (CRM) at each grid column of a general circulation model to replace traditional parameterizations of moist convection and large-scale condensation. This study evaluates the diurnal cycle of deep convection, high-level clouds, and upper troposphere water vapor by applying an infrared (IR) brightness temperature (Tb) and a precipitation radar (PR) simulator to the CRM column data. Simulator results are then compared with IR radiances from geostationary satellites and PR reflectivities from the Tropical Rainfall Measuring Mission (TRMM). While the actual surface precipitation rate in the MMF has a reasonable diurnal phase and amplitude when compared with TRMM observations, the IR simulator results indicate an inconsistency in the diurnal anomalies of high-level clouds between the model and the geostationary satellite data. Primarily because of its excessive high-level clouds, the MMF overestimates the simulated precipitation index (PI) and fails to reproduce the observed diurnal cycle phase relationships among PI, high-level clouds, and upper troposphere relative humidity. The PR simulator results show that over the tropical oceans, the occurrence fraction of reflectivity in excess of 20 dBZ is almost 1 order of magnitude larger than the TRMM data especially at altitudes above 6 km. Both results suggest that the MMF oceanic convection is overactive and possible reasons for this bias are discussed. However, the joint distribution of simulated IR Tb and PR reflectivity indicates that the most intense deep convection is found more often over tropical land than ocean, in agreement with previous observational studies.

Zhang, Yunyan; Klein, Stephen A.; Liu, Chuntao; Tian, Baijun; Marchand, Roger T.; Haynes, J. M.; McCoy, Renata; Zhang, Yuying; Ackerman, Thomas P.

2008-08-22T23:59:59.000Z

79

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

SciTech Connect (OSTI)

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.

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

2013-01-31T23:59:59.000Z

80

Kinematical relations among radar-observed water concentrations, vertical motions, and liquid-water drop-size spectra in convective clouds  

E-Print Network [OSTI]

of return settling are often cloudless or consist of cumulus clouds which have had their growth impeded. If conditions in the atmosphere are favorable, convection cells form and the updraft areas associated with these cells develop into cumulonimbus... and time, M & M(x, y, z, t). The x- and y-directions are horizontal and z-direction is positive toward the zenith. If the quantity M is conservative, the local rate of change at a fixed locality (the local change) can be represented by the following...

Runnels, Robert Clayton

1962-01-01T23:59:59.000Z

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


81

SURFACE TENSION DRIVEN CONVECTION  

E-Print Network [OSTI]

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

Wang, Shouhong

82

Momentum transport processes in the stratiform regions of mesoscale convective systems over the western Pacific warm pool  

E-Print Network [OSTI]

Momentum transport by the stratiform components of mesoscale convective systems (MCSs) during the Tropical OceanĖGlobal Atmosphere Coupled OceanĖAtmosphere Response Experiment in December 1992 is investigated using a ...

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

2006-04-01T23:59:59.000Z

83

Modeling convection in the Greenland Sea  

E-Print Network [OSTI]

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 ...

Bhushan, Vikas

1998-01-01T23:59:59.000Z

84

Building Blocks of Tropical Diabatic Heating  

SciTech Connect (OSTI)

Rotated EOF analyses are used to study the composition and variability of large-scale tropical diabatic heating profiles estimated from eight field campaigns. The results show that the profiles are composed of a pair of building blocks. These are the stratiform heating with peak heating near 400hpa and a cooling peak near 700hPa and convective heating with a heating maximum near 700hPa. Variations in the contributions of these building blocks account for the evolution of the large-scale heating profile. Instantaneous top (bottom) heavy large scale heating profiles associated with excess of stratiform (convective) heating evolve towards a stationary mean profile due to exponential decay of the excess stratiform (convective) heating.

Hagos, Samson M.

2010-07-01T23:59:59.000Z

85

Convective heat transfer inside passive solar buildings  

SciTech Connect (OSTI)

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.

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

1983-01-01T23:59:59.000Z

86

Convective cell development and propagation in a mesoscale convective complex  

E-Print Network [OSTI]

~ , National Fisheries University of Pusan Chairman of Advisory Committee: Dr ~ Kennth CD Brundidge A case study was made of the mesoscale convective complex (MCC) which occurred over southern Oklahoma and northern Texas on 27 May 1981. This storm moved... in an east-southeasterly direction and during much of its lifetime was observable by radars at Oklahoma City, OK and Stephenville, TX. It was found that the direction of cell (VIP level 3 or more reflectivity) propagation was somewhat erratic...

Ahn, Yoo-Shin

2012-06-07T23:59:59.000Z

87

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

SciTech Connect (OSTI)

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

Jensen, Michael

2014-04-10T23:59:59.000Z

88

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

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

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

Jensen, Michael

89

Solar Dynamics, Rotation, Convection and Overshoot  

E-Print Network [OSTI]

We discuss recent observational, theoretical and modeling progress made in understanding the Sun's internal dynamics, including its rotation, meridional flow, convection and overshoot. Over the past few decades, substantial theoretical and observational effort has gone into appreciating these aspects of solar dynamics. A review of these observations, related helioseismic methodology and inference and computational results in relation to these problems is undertaken here.

Hanasoge, S; Roth, M; Schou, J; Schuessler, M; Thompson, M J

2015-01-01T23:59:59.000Z

90

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

E-Print Network [OSTI]

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

Caesar, Kathy-Ann Lois

1995-01-01T23:59:59.000Z

91

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

E-Print Network [OSTI]

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

Wang, Bin

92

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

E-Print Network [OSTI]

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

Restivo, Michael Edward

1995-01-01T23:59:59.000Z

93

Experiment to Characterize Tropical Cloud Systems  

SciTech Connect (OSTI)

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

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

2005-08-02T23:59:59.000Z

94

Tropical Cyclone Intensification from Asymmetric Convection: Energetics and Efficiency  

E-Print Network [OSTI]

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

Nolan, David S.

95

Vertical velocity in oceanic convection off tropical Australia  

E-Print Network [OSTI]

. . . . . . . v Vl Vl I I 1 3 6 10 Description of the Data Data Processing . . Event Criteria 10 15 21 III RESULTS . . . 26 Cores. Environment 26 34 IV COMPARISON WITH OTHER STUDIES . . . . . 40 Cores... Variations with altitude of median and strongest 10'/o-level statistics of (a) average vertical velocity, (b) maximum vertical velocity, (c) mass flux per unit length normal to the flight track and (d) diameter 32 Figure Page Reconstructed temperature...

Lucas, Christopher

2012-06-07T23:59:59.000Z

96

Layer inflow into precipitating convection over the western tropical Pacific  

E-Print Network [OSTI]

and the relativecoarseness of the TOGA COARE soundings.The available input data from the mesoscale model consist of three wind components(u, v and w), temperature, pressure, water vapour, rain water, cloud water and cloudice. The last two quantities, by de? nition, have zero... by linear interpolation of the hourly supplied MM5 data, to the right-hand side of the u, v, w, temperature, pressure and water vapour equations in a narrowzone near the lateral boundaries. The forcing is strongest at the boundary and decreasesto a ? fth...

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

2002-07-01T23:59:59.000Z

97

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment Surfaces and Interfaces Sample6, 2011Liisa O'Neill About Us Liisa O'NeillLimiting

98

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 - September 2006 TheSteven AshbyDepartment ofGE's E.Gilman About UsScience

99

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

SciTech Connect (OSTI)

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

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

2013-11-13T23:59:59.000Z

100

Increase in the Intensity of Postmonsoon Bay of Bengal Tropical Cyclones  

SciTech Connect (OSTI)

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.

Balaguru, Karthik; Taraphdar, Sourav; Leung, Lai-Yung R.; Foltz, Gregory R.

2014-05-28T23:59:59.000Z

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


101

Convective Cloud Lifecycles Lunchtime seminar  

E-Print Network [OSTI]

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

Plant, Robert

102

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

E-Print Network [OSTI]

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

Gadgil, Ashok; Bauman, Fred; Kammerud, Ronald

2008-01-01T23:59:59.000Z

103

Observations  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the ContributionsArmsSpeedingSpeedingUnder Well-ControlledObservation ofof Multiple

104

Tropical and subtropical cloud transitions in weather and climate prediction models: the GCSS/WGNE Pacific Cross-Section Intercomparison (GPCI)  

SciTech Connect (OSTI)

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.

Teixeira, J.; Cardoso, S.; Bonazzola, M.; Cole, Jason N.; DelGenio, Anthony D.; DeMott, C.; Franklin, A.; Hannay, Cecile; Jakob, Christian; Jiao, Y.; Karlsson, J.; Kitagawa, H.; Koehler, M.; Kuwano-Yoshida, A.; LeDrian, C.; Lock, Adrian; Miller, M.; Marquet, P.; Martins, J.; Mechoso, C. R.; Meijgaard, E. V.; Meinke, I.; Miranda, P.; Mironov, D.; Neggers, Roel; Pan, H. L.; Randall, David A.; Rasch, Philip J.; Rockel, B.; Rossow, William B.; Ritter, B.; Siebesma, A. P.; Soares, P.; Turk, F. J.; Vaillancourt, P.; Von Engeln, A.; Zhao, M.

2011-11-01T23:59:59.000Z

105

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

E-Print Network [OSTI]

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.

Poh, Chung-Kiak

2014-01-01T23:59:59.000Z

106

Tropical Underdevelopment Jeffrey D. Sachs  

E-Print Network [OSTI]

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

107

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

E-Print Network [OSTI]

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

108

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

E-Print Network [OSTI]

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

109

Ocean Barrier Layersí Effect on Tropical Cyclone Intensification  

SciTech Connect (OSTI)

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.

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

2012-09-04T23:59:59.000Z

110

Cyclone Center Using Crowdsourcing to Determine Tropical Cyclone Intensity  

E-Print Network [OSTI]

Cyclone Center Using Crowdsourcing to Determine Tropical Cyclone Intensity Almost all tropical cyclones are not directly observed. Agency estimates of storm position and intensity are not homogeneous in time and space. Cyclone Center uses crowdsourcing to collect data that will lead to a consistent

Hennon, Christopher C.

111

Natural convection airflow and heat transport in buildings: experimental results  

SciTech Connect (OSTI)

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.

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

1985-01-01T23:59:59.000Z

112

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

E-Print Network [OSTI]

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

Chen, Tsing-Chang "Mike"

113

Sensitivity of global tropical climate to land surface processes: Mean state and interannual variability  

SciTech Connect (OSTI)

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.

Ma, Hsi-Yen; Xiao, Heng; Mechoso, C. R.; Xue, Yongkang

2013-03-01T23:59:59.000Z

114

Magneto-convection in a sunspot umbra  

E-Print Network [OSTI]

Results from a realistic simulation of 3D radiative magneto-convection in a strong background magnetic field corresponding to the conditions in sunspot umbrae are shown. The convective energy transport is dominated by narrow upflow plumes with adjacent downflows, which become almost field-free near the surface layers. The strong external magnetic field forces the plumes to assume a cusp-like shape in their top parts, where the upflowing plasma loses its buoyancy. The resulting bright features in intensity images correspond well (in terms of brightness, size, and lifetime) to the observed umbral dots in the central parts of sunspot umbrae. Most of the simulated umbral dots have a horizontally elongated form with a central dark lane. Above the cusp, most plumes show narrow upflow jets, which are driven by the pressure of the piled-up plasma below. The large velocities and low field strengths in the plumes are effectively screened from spectroscopic observation because the surfaces of equal optical depth are locally elevated, so that spectral lines are largely formed above the cusp. Our simulations demonstrate that nearly field-free upflow plumes and umbral dots are a natural result of convection in a strong, initially monolithic magnetic field.

M. Schuessler; A. Voegler

2006-03-03T23:59:59.000Z

115

Laser induced natural convection and thermophoresis  

SciTech Connect (OSTI)

The influence of axial laser volumetric heating and forced convection on the motion of aerosol particles in a vertical tube has been studied. The asymptotic case of constant wall temperature provides simple temperature and velocity profiles that determine the convection and thermophoretic motion of small aerosol particles. For the case in which the flow (in the absence of laser heating) is downward, the laser heating induces upward buoyant motion near the tube center. When the laser heating is taken to be constant (a small absorption limit), a velocity profile may be found that will minimize the distance over which particles are deposited on the wall. Such an observation may have some bearing on the manufacture of preforms from which optical fibers are drawn.

Wang, C.Y.; Cipolla, J.; Morse, T.F.

1983-07-01T23:59:59.000Z

116

Eddy formation and propagation in the eastern tropical Pacific  

E-Print Network [OSTI]

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 data show that not all...

Jhingran, Vikas Gopal

1997-01-01T23:59:59.000Z

117

Reduction of tropical land region precipitation variability via transpiration  

E-Print Network [OSTI]

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 ...

Lee, Jung-Eun

118

Heat distribution by natural convection  

SciTech Connect (OSTI)

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.

Balcomb, J.D.

1985-01-01T23:59:59.000Z

119

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

SciTech Connect (OSTI)

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

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

2013-07-01T23:59:59.000Z

120

Biodiversity Conservation in Tropical Agroecosystems  

E-Print Network [OSTI]

Biodiversity Conservation in Tropical Agroecosystems A New Conservation Paradigm Ivette Perfectoa areas of the world. Although most ecologists con- cerned with biodiversity conservation would agree. This conclusion has major consequences for biodiversity con- servation in fragmented tropical forests

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


121

Natural convection heat transfer within horizontal spent nuclear fuel assemblies  

SciTech Connect (OSTI)

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.

Canaan, R.E.

1995-12-01T23:59:59.000Z

122

Heat distribution by natural convection  

SciTech Connect (OSTI)

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.

Balcomb, J.D.

1985-01-01T23:59:59.000Z

123

Convective heat flow probe  

DOE Patents [OSTI]

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.

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

1984-01-09T23:59:59.000Z

124

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

E-Print Network [OSTI]

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

Zuidema, Paquita

125

Tropical Limit in Statistical Physics  

E-Print Network [OSTI]

Tropical limit for macroscopic systems in equilibrium defined as the formal limit of Boltzmann constant k going to 0 is discussed. It is shown that such tropical limit is well-adapted to analyse properties of systems with highly degenerated energy levels, particularly of frustrated systems like spin ice and spin glasses. Tropical free energy is a piecewise linear function of temperature, tropical entropy is a piecewise constant function and the system has energy for which tropical Gibbs' probability has maximum. Properties of systems in the points of jump of entropy are studied. Systems with finite and infinitely many energy levels and phenomena of limiting temperatures are discussed.

M. Angelelli; B. Konopelchenko

2015-02-04T23:59:59.000Z

126

Natural convection airflow measurement and theory  

SciTech Connect (OSTI)

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.

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

1984-01-01T23:59:59.000Z

127

Inter-annual Tropospheric Aerosol Variability in Late Twentieth Century and its Impact on Tropical Atlantic and West African Climate by Direct and Semi-direct Effects  

SciTech Connect (OSTI)

A new high-resolution (0.9$^{\\circ}$x1.25$^{\\circ}$ in the horizontal) global tropospheric aerosol dataset with monthly resolution is generated using the finite-volume configuration of Community Atmosphere Model (CAM4) coupled to a bulk aerosol model and forced with recent estimates of surface emissions for the latter part of twentieth century. The surface emissions dataset is constructed from Coupled Model Inter-comparison Project (CMIP5) decadal-resolution surface emissions dataset to include REanalysis of TROpospheric chemical composition (RETRO) wildfire monthly emissions dataset. Experiments forced with the new tropospheric aerosol dataset and conducted using the spectral configuration of CAM4 with a T85 truncation (1.4$^{\\circ}$x1.4$^{\\circ}$) with prescribed twentieth century observed sea surface temperature, sea-ice and greenhouse gases reveal that variations in tropospheric aerosol levels can induce significant regional climate variability on the inter-annual timescales. Regression analyses over tropical Atlantic and Africa reveal that increasing dust aerosols can cool the North African landmass and shift convection southwards from West Africa into the Gulf of Guinea in the spring season in the simulations. Further, we find that increasing carbonaceous aerosols emanating from the southwestern African savannas can cool the region significantly and increase the marine stratocumulus cloud cover over the southeast tropical Atlantic ocean by aerosol-induced diabatic heating of the free troposphere above the low clouds. Experiments conducted with CAM4 coupled to a slab ocean model suggest that present day aerosols can shift the ITCZ southwards over the tropical Atlantic and can reduce the ocean mixed layer temperature beneath the increased marine stratocumulus clouds in the southeastern tropical Atlantic.

Evans, Katherine J [ORNL; Hack, James J [ORNL; Truesdale, John [National Center for Atmospheric Research (NCAR); Mahajan, Salil [ORNL; Lamarque, J-F [University Center for Atmospheric Research

2012-01-01T23:59:59.000Z

128

Mechanisms of Remote Tropical Surface Warming during El Nio JOHN C. H. CHIANG AND BENJAMIN R. LINTNER  

E-Print Network [OSTI]

temperature) for the remote tropical surface warming. Over the remote oceans, latent heat flux acting throughMechanisms of Remote Tropical Surface Warming during El Ni√Īo JOHN C. H. CHIANG AND BENJAMIN R.10) simulations of the 1997/98 El Ni√Īo that the observed "remote" (i.e., outside the Pacific) tropical land

Lintner, Benjamin Richard

129

AMIE (ARM MJO Investigation Experiment): Observations of the Madden-Julian Oscillation for Modeling Studies Science Plan  

SciTech Connect (OSTI)

Deep convection in the tropics plays an important role in driving global circulations and the transport of energy from the tropics to the mid-latitudes. Understanding the mechanisms that control tropical convection is a key to improving climate modeling simulations of the global energy balance. One of the dominant sources of tropical convective variability is the Madden-Julian Oscillation (MJO), which has a period of approximately 30Ė60 days. There is no agreed-upon explanation for the underlying physics that maintain the MJO. Many climate models do not show well-defined MJO signals, and those that do have problems accurately simulating the amplitude, propagation speed, and/or seasonality of the MJO signal. Therefore, the MJO is a very important modeling target for the ARM modeling community geared specifically toward improving climate models. The ARM MJO Investigation Experiment (AMIE) period coincides with a large international MJO initiation field campaign called CINDY2011 (Cooperative Indian Ocean experiment on intraseasonal variability in the Year 2011) that will take place in and around the Indian Ocean from October 2011 to January 2012. AMIE, in conjunction with CINDY2011 efforts, will provide an unprecedented data set that will allow investigation of the evolution of convection within the framework of the MJO. AMIE observations will also complement the long-term MJO statistics produced using ARM Manus data and will allow testing of several of the current hypotheses related to the MJO phenomenon. Taking advantage of the expected deployment of a C-POL scanning precipitation radar and an ECOR surface flux tower at the ARM Manus site, we propose to increase the number of sonde launches to eight per day starting in about mid-October of the field experiment year, which is climatologically a period of generally suppressed conditions at Manus and just prior to the climatologically strongest MJO period. The field experiment will last until the end of the MJO season (typically March), affording the documentation of conditions before, during, and after the peak MJO season. The increased frequency of sonde launches throughout the experimental period will provide better diurnal understanding of the thermodynamic profiles, and thus a better representation within the variational analysis data set. Finally, a small surface radiation and ceilometer system will be deployed at the PNG Lombrum Naval Base about 6 km away from the ARM Manus site in order to provide some documentation of scale variability with respect to the representativeness of the ARM measurements.

Long, C; Del Genio, A; Gustafson, W; Houze, R; Jakob, C; Jensen, M; Klein, S; Leung, L Ruby; Liu, X; Luke, E; May, P; McFarlane, S; Minnis, P; Schumacher, C; Vogelmann, A; Wang, Y; Wu, X; Xie, S

2010-03-22T23:59:59.000Z

130

Convection induced by radiative cooling of a layer of participating medium  

SciTech Connect (OSTI)

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

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

2014-05-15T23:59:59.000Z

131

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

SciTech Connect (OSTI)

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.

Dudhia, Jimy

2013-03-12T23:59:59.000Z

132

ARM - Midlatitude Continental Convective Clouds  

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

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.

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

133

Midlatitude Continental Convective Clouds Experiment (MC3E)  

SciTech Connect (OSTI)

Convective processes play a critical role in the Earthís 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 Earthís 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 ďparameterizationsĒ 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 AprilĖMay 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 Administrationís (NASA) Global Precipitation Measurement (GPM) mission Ground Validation (GV) program. The field campaign leverages the unprecedented observing infrastructure currently available in the central United States, combined with an extensive sounding array, remote sensing and in situ aircraft observations, NASA GPM ground validation remote sensors, and new ARM instrumentation purchased with American Recovery and Reinvestment Act funding. The overarching goal is to provide the most complete characterization of convective cloud systems, precipitation, and the environment that has ever been obtained, providing constraints for model cumulus parameterizations and space-based rainfall retrieval algorithms over land that have never before been available. Several different components of convective cloud and precipitation processes tangible to both the convective parameterization and precipitation retrieval algorithm problem are targeted, such as preconvective environment and convective initiation, updraft/downdraft dynamics, condensate transport and detrainment, precipitation and cloud microphysics, spatial and temporal variability of precipitation, influence on the environment and radiation, and a detailed description of the large-scale forcing.

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

2010-04-01T23:59:59.000Z

134

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

E-Print Network [OSTI]

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

Toracinta, Ernest Richard

1995-01-01T23:59:59.000Z

135

NATURAL CONVECTION IN ROOM GEOMETRIES  

SciTech Connect (OSTI)

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.

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

1980-06-01T23:59:59.000Z

136

3D Simulation of Convection and Spectral Line Formation in A-type Stars  

E-Print Network [OSTI]

We present first realistic numerical simulations of 3D radiative convection in the surface layers of main sequence A-type stars with Teff = 8000 K and 8500 K, log g = 4.4 and 4.0, recently performed with the CO5BOLD radiation hydrodynamics code. The resulting models are used to investigate the structure of the H+HeI and the HeII convection zones in comparison with the predictions of local and non-local convection theories, and to determine the amount of "overshoot" into the stable layers below the HeII convection zone. The simulations also predict how the topology of the photospheric granulation pattern changes from solar to A-type star convection. The influence of the photospheric temperature fluctuations and velocity fields on the shape of spectral lines is demonstrated by computing synthetic line profiles and line bisectors for some representative examples, allowing us to confront the 3D model results with observations.

M. Steffen; B. Freytag; H. -G. Ludwig

2005-09-15T23:59:59.000Z

137

Ten Years of Measurements of Tropical Upper-Tropospheric Water Vapor by MOZAIC. Part I: Climatology, Variability, Transport, and Relation to  

E-Print Network [OSTI]

the International Satellite Cloud Climatology Project (ISCCP). 1. Introduction Water vapor is the key atmosphericTen Years of Measurements of Tropical Upper-Tropospheric Water Vapor by MOZAIC. Part I: Climatology, Variability, Transport, and Relation to Deep Convection ZHENGZHAO LUO, DIETER KLEY,* AND RICHARD H. JOHNSON

Lombardi, John R.

138

Copyrighted Material What Is Tropical Ecology?  

E-Print Network [OSTI]

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

Landweber, Laura

139

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

E-Print Network [OSTI]

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

Humbert, Mark Edward

1980-01-01T23:59:59.000Z

140

Midlatitude Continental Convective Clouds Experiment (MC3E)  

SciTech Connect (OSTI)

The Midlatitude Continental Convective Clouds Experiment (MC3E) will take place in central Oklahoma during the AprilĖMay 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 Administrationís (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.

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

2010-04-10T23:59:59.000Z

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


141

Energy transport using natural convection boundary layers  

SciTech Connect (OSTI)

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

Anderson, R.

1986-04-01T23:59:59.000Z

142

Slide 1Falk Herwig7 Aug 2006 Convective and non-convective mixing  

E-Print Network [OSTI]

Slide 1Falk Herwig7 Aug 2006 Convective and non-convective mixing in AGB stars Falk Herwig and Bernd Freytag Los Alamos National Laboratory Theoretical Astrophysics Group #12;Slide 2Falk Herwig7 Aug envelope models for sun-like stars #12;Slide 3Falk Herwig7 Aug 2006 3D hydro simulations of AGB convective

Herwig, Falk

143

Advection, Moistening, and Shallow-to-deep Convection Transitions During the Initiation and Propagation of Madden-Julian Oscillation  

SciTech Connect (OSTI)

Using observations from the 2011 AMIE/DYNAMO field campaign over the Indian Ocean and a high-resolution regional model simulation, the processes that lead to the rapid shallow-to-deep convection transitions associated with the initiation and eastward propagation of the Madden-Julian Oscillation (MJO) are examined. By tracking the evolution of the depth of several thousand individual model simulated precipitation features, the role of and the processes that control the observed midtropospheric moisture buildup ahead of the detection of deep convection are quantified at large and convection scales. The frequency of shallow-to-deep convection transitions is found to be sensitive to this midlevel moisture and large-scale uplift. This uplift along with the decline of large-scale drying by equator-ward advection causes the moisture buildup leading to the initiation of the MJO. Convection scale moisture variability and uplift, and large-scale zonal advection play secondary roles.

Hagos, Samson M.; Feng, Zhe; Landu, Kiranmayi; Long, Charles N.

2014-09-11T23:59:59.000Z

144

AERIAL MEASUREMENTS OF CONVECTION CELL ELEMENTS IN HEATED LAKES  

SciTech Connect (OSTI)

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

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

2007-12-19T23:59:59.000Z

145

Realistic Solar Convection Simulations Robert F. Stein  

E-Print Network [OSTI]

Realistic Solar Convection Simulations Robert F. Stein Michigan State University, East Lansing, MIAFG, Juliane Maries Vej 30, Dk¬≠2100 Copenhagen √?, Denmark Abstract. We report on realistic simulations of solar and intensity spectra, the p¬≠mode excitation rate, and the depth of the convection zone. We describe how solar

Stein, Robert

146

The excitation of solar-like oscillations in a delta Scuti star by efficient envelope convection  

E-Print Network [OSTI]

Delta Scuti (delta Sct) stars are opacity-driven pulsators with masses of 1.5-2.5M$_{\\odot}$, their pulsations resulting from the varying ionization of helium. In less massive stars such as the Sun, convection transports mass and energy through the outer 30 per cent of the star and excites a rich spectrum of resonant acoustic modes. Based on the solar example, with no firm theoretical basis, models predict that the convective envelope in delta Sct stars extends only about 1 per cent of the radius, but with sufficient energy to excite solar-like oscillations. This was not observed before the Kepler mission, so the presence of a convective envelope in the models has been questioned. Here we report the detection of solar-like oscillations in the delta Sct star HD 187547, implying that surface convection operates efficiently in stars about twice as massive as the Sun, as the ad hoc models predicted.

Antoci, V; Campante, T L; Thygesen, A O; Moya, A; Kallinger, T; Stello, D; GrigahcŤne, A; Kjeldsen, H; Bedding, T R; LŁftinger, T; Christensen-Dalsgaard, J; Catanzaro, G; Frasca, A; De Cat, P; Uytterhoeven, K; Bruntt, H; Houdek, G; Kurtz, D W; Lenz, P; Kaiser, A; Van Cleve, J; Allen, C; Clarke, B D

2011-01-01T23:59:59.000Z

147

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

SciTech Connect (OSTI)

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.

Fitzpatrick, M.E.

1992-01-01T23:59:59.000Z

148

Collective phase description of oscillatory convection  

SciTech Connect (OSTI)

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

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

2013-12-15T23:59:59.000Z

149

Ocean dynamics and thermodynamics in the tropical Indo- Pacific region  

E-Print Network [OSTI]

Pacific Oceans . . . . . . . . . . . . . . . . . . . . . . . . . . . . .currents in the tropical Pacific Ocean. J. Phys. Oceanogr. ,in the eastern tropical Pacific Ocean associated with the

Drushka, Kyla

2011-01-01T23:59:59.000Z

150

Diamagnetic pumping near the base of a stellar convection zone  

E-Print Network [OSTI]

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

L. L. Kitchatinov; G. RŁdiger

2008-02-18T23:59:59.000Z

151

EVIDENCE FOR CONVECTION IN SUNSPOT PENUMBRAE  

SciTech Connect (OSTI)

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.

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

2010-10-20T23:59:59.000Z

152

Midlevel Ventilation's Constraint on Tropical Cyclone Intensity  

E-Print Network [OSTI]

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

Tang, Brian Hong-An

153

Elements of tropical Pacific decadal variability  

E-Print Network [OSTI]

potential to change the background state of the eastern tropical Pacific. Simultaneously, a redistribution of atmospheric vorticity in the western tropical Pacific affects isopycnal depth and therefore ocean thermal structure progressing the decadal change...

Fuckar, Neven-Stjepan

2003-01-01T23:59:59.000Z

154

Tropical Fruit Ambrosia Makes 6 servings  

E-Print Network [OSTI]

Tropical Fruit Ambrosia Makes 6 servings 1 jar (26 oz.) mixed tropical fruit, drained 1 large coconut Lettuce leaves Directions: 1. In a large bowl, combine the tropical fruit and banana. 2. In a small bowl, stir together the yogurt, lime zest, and lime juice until blended. 3. Spoon over the fruit

Florida, University of

155

Conclusions Observed enhancement in convection heat transfer coefficient in  

E-Print Network [OSTI]

in de-ionized water Commercial System Heater Insulation Water block · The water block replaces/min) di-water 1% nanofluid 0.5% nanofluid Results: Calculated Thermal Conductivity 0.45 0.5 0.55 0.6 0.65 0.7 0.75 0.8 0.85 0 0.5 1 1.5 2 thermalconductivity(W/mK) volume loading (%) calculated di-water

Walker, D. Greg

156

Title: Radar-observed convective characteristics during TWP-ICE  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched Ferromagnetism in Layered NbS2 andThe1A:decisional. 1 B O NAmes Blue

157

Convective heat transfer inside passive solar buildings  

SciTech Connect (OSTI)

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.

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

1983-11-01T23:59:59.000Z

158

Structure and evolution of a convective band MCS  

E-Print Network [OSTI]

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

Valdes-Manzanilla, Arturo

1995-01-01T23:59:59.000Z

159

Convective Cooling and Passive Stack Improvements in Motors (Presentation)  

SciTech Connect (OSTI)

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

Bennion, K.

2014-06-01T23:59:59.000Z

160

Estimation of Convection Loss from Paraboloidal Dish Cavity Receivers  

E-Print Network [OSTI]

presents new results from an investigation of natural and combined convection heat transfer from open in which force convection dominates can be clarified. 1. INTRODUCTION Convective heat transfer and numerical investigation of natural convection heat transfer has also been published in Taumoefolau et al

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


161

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

E-Print Network [OSTI]

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... by MICHAEL EUGENE HOOFARD Approved as to style and content by: a ter . enry (Chairman of Committee) %~5 44 c5 c usan gur c (Member) ona . oc ing (Member) ames . cogg (Head of Department) August 1986 ABSTRACT Nesoscale Convective Complex vs. Non...

Hoofard, Michael Eugene

1986-01-01T23:59:59.000Z

162

SUMMARY OF 2013 ATLANTIC TROPICAL CYCLONE ACTIVITY AND VERIFICATION OF AUTHORS' SEASONAL AND TWO-WEEK FORECASTS  

E-Print Network [OSTI]

. In addition, Accumulated Cyclone Energy (ACE) was the lowest that has been observed since 1983. This year Cyclone Energy (ACE) (92) 165 165 142 30 32% Net Tropical Cyclone Activity (NTC) (103%) 175 175 150 43 42SUMMARY OF 2013 ATLANTIC TROPICAL CYCLONE ACTIVITY AND VERIFICATION OF AUTHORS' SEASONAL AND TWO

163

Climatology and Formation of Tropical Midlevel Clouds at the Darwin ARM Site  

SciTech Connect (OSTI)

A 4-yr climatology of midlevel clouds is presented from vertically pointing cloud lidar and radar measurements at the Atmospheric Radiation Measurement Program (ARM) site at Darwin, Australia. Few studies exist of tropical midlevel clouds using a dataset of this length. Seventy percent of clouds with top heights between 4 and 8 km are less than 2 km thick. These thin layer clouds have a peak in cloud-top temperature around the melting level (0įC) and also a second peak around -12.5įC. The diurnal frequency of thin clouds is highest during the night and reaches a minimum around noon, consistent with variation caused by solar heating. Using a 1.5-yr subset of the observations, the authors found that thin clouds have a high probability of containing supercooled liquid water at low temperatures: ~20% of clouds at -30įC, ~50% of clouds at -20įC, and ~65% of clouds at -10įC contain supercooled liquid water. The authors hypothesize that thin midlevel clouds formed at the melting level are formed differently during active and break monsoon periods and test this over three monsoon seasons. A greater frequency of thin midlevel clouds are likely formed by increased condensation following the latent cooling of melting during active monsoon periods when stratiform precipitation is most frequent. This is supported by the high percentage (65%) of midlevel clouds with preceding stratiform precipitation and the high frequency of stable layers slightly warmer than 0įC. In the break monsoon, a distinct peak in the frequency of stable layers at 0įC matches the peak in thin midlevel cloudiness, consistent with detrainment from convection.

Riihimaki, Laura D.; McFarlane, Sally A.; Comstock, Jennifer M.

2012-10-01T23:59:59.000Z

164

Tropical rainforest biodiversity: field and  

E-Print Network [OSTI]

. The Udzungwas in particular, are one of the single, most important areas in Africa for biodiversity conservationTropical rainforest biodiversity: field and GIS tools for assessing, monitoring and mapping II with Tanzania National ParksTanzania National Parks andand Wildlife Conservation SocietyWildlife Conservation

165

Circulation and convection in the Irminger Sea  

E-Print Network [OSTI]

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 ...

VŚge, Kjetil

2010-01-01T23:59:59.000Z

166

Seismic Sounding of Convection in the Sun  

E-Print Network [OSTI]

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

Hanasoge, Shravan; Sreenivasan, Katepalli R

2015-01-01T23:59:59.000Z

167

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

E-Print Network [OSTI]

the two years tend to follow these patterns. There was a greater number of MCSs in the Central Pacific and East Pacific in the El Nino year and fewer MCSs in the Maritime Continent. The area distributions and median intensities of MCSs were found...

Zolman, Jody Lynn

1999-01-01T23:59:59.000Z

168

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc DocumentationP-SeriesFlickrinformation for and Application deadline: November

169

Tropical Cloud Properties and Radiative Heating Profiles  

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

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.

Mather, James

170

Ecotoxicology of tropical marine ecosystems  

SciTech Connect (OSTI)

The negative effects of chemical contaminants on tropical marine ecosystems are of increasing concern as human populations expand adjacent to these communities. Watershed streams and ground water carry a variety of chemicals from agricultural, industrial, and domestic activities, while winds and currents transport pollutants from atmospheric and oceanic sources to these coastal ecosystems. The implications of the limited information available on impacts of chemical stressors on mangrove forests, seagrass meadows, and coral reefs are discussed in the context of ecosystem management and ecological risk assessment. Three classes of pollutants have received attention: heavy metals, petroleum, and synthetic organics. Heavy metals have been detected in all three ecosystems, causing physiological stress, reduced reproductive success, and outright mortality in associated invertebrates and fishes. Oil spills have been responsible for the destruction of entire coastal shallow-water communities, with recovery requiring years. Herbicides are particularly detrimental to mangroves and seagrasses and adversely affect the animal-algal symbioses in corals. Pesticides interfere with chemical cues responsible for key biological processes, including reproduction and recruitment of a variety of organisms. Information is lacking with regard to long-term recovery, indicator species, and biomarkers for tropical communities. Critical areas that are beginning to be addressed include the development of appropriate benchmarks for risk assessment, baseline monitoring criteria, and effective management strategies to protect tropical marine ecosystems in the face of mounting anthropogenic disturbance.

Peters, E.C. [Tetra Tech, Inc., Fairfax, VA (United States); Gassman, N.J.; Firman, J.C. [Univ. of Miami, FL (United States). Rosenstiel School of Marine and Atmospheric Science; Richmond, R.H. [Univ. of Guam, Mangilao (Guam). Marine Lab.; Power, E.A. [EVS Environment Consultants, Ltd., North Vancouver, British Columbia (Canada)

1997-01-01T23:59:59.000Z

171

Under consideration for publication in J. Fluid Mech. 1 Stressed horizontal convection  

E-Print Network [OSTI]

in the Gullmarfjord on the west coast of Sweden. When the wind swept over the fjord, the water at the surface flowed to the suggestion of Munk & Wunsch (1998) that mechanical energy sources -- such as the wind stress observed by Sandstr®om (1908) -- are necessary to sustain the ocean circulation. Recent work on horizontal convection

Young, William R.

172

Using CASA IP1 to Diagnose Kinematic and Microphysical Interactions in a Convective Storm  

E-Print Network [OSTI]

bulk hydrometeor identification and dual-Doppler wind retrievals. Comparisons are made with the nearby-band radars are used to observe a convective storm. A fuzzy logic hydrometeor identification algorithm the type of echoes in the network based on storm identification al- gorithms, then allocates radars

Rutledge, Steven

173

Asteroseismic Diagnostics of Stellar Convective Cores  

E-Print Network [OSTI]

We present a detailed study of the small frequency separations as diagnostics of the mass of the convective core and evolutionary stage of solar-type stars. We demonstrate how the small separations can be combined to provide sensitive tests for the presence of convective overshoot at the edge of the core. These studies are focused on low degree oscillation modes, the only modes expected to be detected in distant stars. Using simulated data with realistic errors, we find that the mass of the convective core can be estimated to within 5% if the total stellar mass is known. Systematic errors arising due to uncertainty in the mass could be up to 20%. The evolutionary stage of the star, determined in terms of the central hydrogen abundance using our proposed technique, however, is much less sensitive to the mass estimate.

Anwesh Mazumdar; Sarbani Basu; Braxton L. Collier; Pierre Demarque

2006-08-16T23:59:59.000Z

174

The Role of the Tropics in Abrupt Climate Changes  

SciTech Connect (OSTI)

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

Fedorov, Alexey [Yale University] [Yale University

2013-12-07T23:59:59.000Z

175

Influence of Tropical Tropopause Layer Cooling on Atlantic Hurricane Activity  

E-Print Network [OSTI]

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

Solomon, Susan

176

Stellar models with mixing length and T(tau) relations calibrated on 3D convection simulations  

E-Print Network [OSTI]

(abridged) The calculation of the thermal stratification in the superadiabatic layers of stellar models with convective envelopes is a long standing problem of stellar astrophysics, and has a major impact on predicted observational properties like radius and effective temperature. The Mixing Length Theory, almost universally used to model the superadiabatic convective layers, contains effectively one free parameter to be calibrated --alpha(ml)-- whose value controls the resulting effective temperature. Here we present the first self-consistent stellar evolution models calculated by employing the atmospheric temperature stratification, Rosseland opacities, and calibrated variable alpha(ml) (dependent on effective temperature and surface gravity) from a large suite of three-dimensional radiation hydrodynamics simulations of stellar convective envelopes and atmospheres for solar stellar composition (Trampedach et al. 2013). From our calculations (with the same composition of the radiation hydrodynamics simulatio...

Salaris, Maurizio

2015-01-01T23:59:59.000Z

177

Origins of convective activity over Panama  

E-Print Network [OSTI]

Satellite-derived outgoing longwave radiation (OLR) data. were used to examine convective variability over the Panama region. Time series analysis of the area- averaged daily OLR data, for 1984 and 1985 revealed a, persistent 12-d oscillation... in convective activity during each season. Composite analyses of OLR data, for the area 120'W-40'W and 35'S-35'N for the 1984 dry (1 January ? 9 May) and wet (10 Msy? 4 December) seasons showed this oscillation extends beyond Panama and the Central America...

Strager, Christopher Stephen

1989-01-01T23:59:59.000Z

178

Convection and dynamo action in B stars  

E-Print Network [OSTI]

Main-sequence massive stars possess convective cores that likely harbor strong dynamo action. To assess the role of core convection in building magnetic fields within these stars, we employ the 3-D anelastic spherical harmonic (ASH) code to model turbulent dynamics within a 10 solar mass main-sequence (MS) B-type star rotating at 4 times the solar rate. We find that strong (900 kG) magnetic fields arise within the turbulence of the core and penetrate into the stably stratified radiative zone. These fields exhibit complex, time-dependent behavior including reversals in magnetic polarity and shifts between which hemisphere dominates the total magnetic energy.

Augustson, Kyle C; Toomre, Juri

2010-01-01T23:59:59.000Z

179

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

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

Trapped Lignin-Degrading Microbes in Tropical Forest Soil. Characterization of Trapped Lignin-Degrading Microbes in Tropical Forest Soil. Abstract: Lignin is often the most...

180

Simulation of Convection and Macrosegregation in a Large Steel Ingot  

E-Print Network [OSTI]

Simulation of Convection and Macrosegregation in a Large Steel Ingot J.P. GU and C. BECKERMANN Melt convection and macrosegregation in casting of a large steel ingot are numerically simulated. The simulation is based on a previously developed model for multicomponent steel solidification with melt convection

Beckermann, Christoph

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


181

Realistic Solar Surface Convection Simulations Robert F. Stein  

E-Print Network [OSTI]

Realistic Solar Surface Convection Simulations Robert F. Stein Michigan State University, East free simulations with re­ alistic physics of convection near the solar surface. We summarize solar convection is non­local. It is driven from a thin surface thermal boundary layer where radiative

Stein, Robert

182

Tropical Western Pacific CART Site  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched Ferromagnetism in Layered NbS2TopoPortalBRDF Effects inHeterogeneousTropical

183

Observational and numerical study of Atlantic tropical instability waves  

E-Print Network [OSTI]

regional climate model and one global climate model are applied to study the mechanism of atmospheric response to the Atlantic TIWs with daily TMI satellite SST forcing. Both models successfully simulated the wind velocity, wind convergence and pre...

Wu, Qiaoyan

2009-06-02T23:59:59.000Z

184

PHYSICAL, CHEMICAL, AND BIOLOGICAL OBSERVATIONS IN THE EASTERN TROPICAL  

E-Print Network [OSTI]

. Thomas University of California Scripps Institution of Oceanography La Jolla, California United States phosphorus 6 Nitrate, nitrite, and silicate 7 Incident solar radiation : 7 Submarine daylight 7 Chlorophyll Cali- fornia, thence across the mouth of the Gulf of California and along the coast of southern Mexico

185

Tropical anvil cirrus evolution from observations and numerical simulations  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched Ferromagnetism in Layered NbS2TopoPortalBRDF EffectsPacific: A Year in

186

ORIGINAL ARTICLE Mitigation needs adaptation: Tropical forestry  

E-Print Network [OSTI]

ORIGINAL ARTICLE Mitigation needs adaptation: Tropical forestry and climate change Manuel R adapt to this change. This paper discusses how tropical forestry practices can contribute to maintaining Forestry Research, P.O. Box 6596 JKPWB, Jakarta 10065, Indonesia e-mail: m.guariguata@cgiar.org J. P

Paris-Sud XI, Université de

187

The effect of convection on pulsational stability  

E-Print Network [OSTI]

A review on the current state of mode physics in classical pulsators is presented. Two, currently in use, time-dependent convection models are compared and their applications on mode stability are discussed with particular emphasis on the location of the Delta Scuti instability strip.

G. Houdek

2008-10-29T23:59:59.000Z

188

Laminar boundary layers in convective heat transport  

E-Print Network [OSTI]

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.

Christian Seis

2012-12-12T23:59:59.000Z

189

Convective Instability of a Boundary Layer with  

E-Print Network [OSTI]

proportional to the integral over the depth of the lithosphere of the 19 #12;ratio of thermal buoyancy. Such instabilities are driven by the negative thermal buoyancy of the cold lithosphere and retarded largely for driving convective downwelling. For non-Newtonian viscosity with power law exponent n and temperature

Conrad, Clint

190

Convective and absolute instabilities in eccentric Taylor  

E-Print Network [OSTI]

Convective and absolute instabilities in eccentric Taylor Laboratoire de m√©canique des fluides et d and absolute instabilities in Taylor-Couette-Poiseuille flow Beno√ģt PIER Laboratoire de m√©canique des fluides flow type often disrupt oil-well drilling By implementing a detailed instability analysis, the dynamics

Shyamasundar, R.K.

191

Solar MagnetoConvection David J. Bercik  

E-Print Network [OSTI]

Solar Magneto¬≠Convection David J. Bercik Dept. of Physics and Astronomy, Michigan State University, Michigan State University, East Lansing, MI 48824, U.S.A. Ň° Ake Nordlund Theoretical Astrophysics Center, √?ster Voldgade 3, 1350 Copenhagen K, Denmark Robert F. Stein Dept. of Physics and Astronomy, Michigan

Stein, Robert

192

EFFECTS OF ASYMMETRIC FLOWS IN SOLAR CONVECTION ON OSCILLATION MODES  

SciTech Connect (OSTI)

Many helioseismic measurements suffer from substantial systematic errors. A particularly frustrating one is that time-distance measurements suffer from a large center to limb effect which looks very similar to the finite light travel time, except that the magnitude depends on the observable used and can have the opposite sign. This has frustrated attempts to determine the deep meridional flow in the solar convection zone, with Zhao et al. applying an ad hoc correction with little physical basis to correct the data. In this Letter, we propose that part of this effect can be explained by the highly asymmetrical nature of the solar granulation which results in what appears to the oscillation modes as a net radial flow, thereby imparting a phase shift on the modes as a function of observing height and thus heliocentric angle.

Baldner, Charles S.; Schou, Jesper, E-mail: baldner@stanford.edu [W.W. Hansen Experimental Physics Laboratory, Stanford University, Stanford, CA 94305-4085 (United States)

2012-11-20T23:59:59.000Z

193

Operating temperatures for a convectively cooled recessed incandescent light fixture  

SciTech Connect (OSTI)

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

Yarbrough, D.W.; Toor, I.

1980-12-01T23:59:59.000Z

194

CONVECTION THEORY AND SUB-PHOTOSPHERIC STRATIFICATION  

SciTech Connect (OSTI)

As a preliminary step toward a complete theoretical integration of three-dimensional compressible hydrodynamic simulations into stellar evolution, convection at the surface and sub-surface layers of the Sun is re-examined, from a restricted point of view, in the language of mixing-length theory (MLT). Requiring that MLT use a hydrodynamically realistic dissipation length gives a new constraint on solar models. While the stellar structure which results is similar to that obtained by Yale Rotational Evolution Code (Guenther et al.; Bahcall and Pinsonneault) and Garching models (Schlattl et al.), the theoretical picture differs. A new quantitative connection is made between macro-turbulence, micro-turbulence, and the convective velocity scale at the photosphere, which has finite values. The 'geometric parameter' in MLT is found to correspond more reasonably with the thickness of the superadiabatic region (SAR), as it must for consistency in MLT, and its integrated effect may correspond to that of the strong downward plumes which drive convection (Stein and Nordlund), and thus has a physical interpretation even in MLT. If we crudely require the thickness of the SAR to be consistent with the 'geometric factor' used in MLT, there is no longer a free parameter, at least in principle. Use of three-dimensional simulations of both adiabatic convection and stellar atmospheres will allow the determination of the dissipation length and the geometric parameter (i.e., the entropy jump) more realistically, and with no astronomical calibration. A physically realistic treatment of convection in stellar evolution will require substantial additional modifications beyond MLT, including nonlocal effects of kinetic energy flux, entrainment (the most dramatic difference from MLT found by Meakin and Arnett), rotation, and magnetic fields.

Arnett, David; Meakin, Casey; Young, Patrick A., E-mail: darnett@as.arizona.ed, E-mail: casey.meakin@gmail.co, E-mail: patrick.young.1@asu.ed [Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States)

2010-02-20T23:59:59.000Z

195

Rapid transport of East Asian pollution to the deep tropics  

E-Print Network [OSTI]

, and biomass burning in tropical continental Southeast Asia: observations in rural Thai- land, J. Geophys. Res.-Atmos., 108, 4552, doi:10.1029/2002JD003360, 2003. 30708 Pyle, J. A., Ashfold, M. J., Harris, N. R. P., Robinson, A. D., Warwick, N. J., Carver, G. D... mid-latitudes rapidly to equatorial Southeast Asia.15 4 Wider air quality implications Thus far we have focussed on C2Cl4, an industrial pollutant observed in relatively small quantities. It is clearly of interest to consider how this pollution...

Ashfold, M. J.; Pyle, J. A.; Robinson, A. D.; Nadzir, M. S. M.; Phang, S. M.; Samah, A. A.; Ong, S.; Ung, H. E.; Peng, L. K.; Yong, S. E.; Harris, N. R. P.

2014-12-05T23:59:59.000Z

196

The Generation of a Mesoscale Convective System from Mountain Convection  

E-Print Network [OSTI]

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

Tucker, Donna F.; Crook, N. Andrew

1999-06-01T23:59:59.000Z

197

The impact of tropical cyclones (TC) on global climate is still debated. They rapidly mix the water column beneath them, bringing cold water to the surface.  

E-Print Network [OSTI]

of Climate, 21, 638 Sriver & Huber, 2007, Observational evidence for an ocean heat pump induced by tropicalThe impact of tropical cyclones (TC) on global climate is still debated. They rapidly mix the water column beneath them, bringing cold water to the surface. One way to parameterise this process

Jones, Peter JS

198

Final Report on Evaluating the Representation and Impact of Convective Processes in the NCAR Community Climate System Model  

SciTech Connect (OSTI)

Convection and clouds affect atmospheric temperature, moisture and wind fields through the heat of condensation and evaporation and through redistributions of heat, moisture and momentum. Individual clouds have a spatial scale of less than 10 km, much smaller than the grid size of several hundred kilometers used in climate models. Therefore the effects of clouds must be approximated in terms of variables that the model can resolve. Deriving such formulations for convection and clouds has been a major challenge for the climate modeling community due to the lack of observations of cloud and microphysical properties. The objective of our DOE CCPP project is to evaluate and improve the representation of convection schemes developed by PIs in the NCAR (National Center for Atmospheric Research) Community Climate System Model (CCSM) and study its impact on global climate simulations. ē The project resulted in nine peer-reviewed publications and numerous scientific presentations that directly address the CCPPís scientific objective of improving climate models. ē We developed a package of improved convection parameterization that includes improved closure, trigger condition for convection, and comprehensive treatment of convective momentum transport. ē We implemented the new convection parameterization package into several versions of the NCAR models (both coupled and uncoupled). This has led to 1) Improved simulation of seasonal migration of ITCZ; 2) Improved shortwave cloud radiative forcing response to El NiŮo in CAM3; 3) Improved MJO simulation in both uncoupled and coupled model; and 4) Improved simulation of ENSO in coupled model. ē Using the dynamic core of CCM3, we isolated the dynamic effects of convective momentum transport. ē We implemented mosaic treatment of subgrid-scale cloud-radiation interaction in CCM3.

X. Wu, G. J. Zhang

2008-04-23T23:59:59.000Z

199

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

SciTech Connect (OSTI)

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.

Lackmann, Gary

2013-06-10T23:59:59.000Z

200

Thermocapillary convection induced by laser surface heating  

SciTech Connect (OSTI)

Thermocapillary convection was excited by a laser source in experiments on molten paraffin. The parameters of the resultant flow were determined. The nature of the flow was demonstrated to correspond to shear-driven boundary-layer flow at high Reynolds numbers. Correlation dependences of the flow velocity of the melt and its temperature in the surface region were derived theoretically and were shown to agree with the experimental results. When the size of the laser spot was much less than the characteristic convection scales, three regions of flow of the melt could be distinguished: a viscous surface boundary layer, a stagnation zone under the laser spot, and a large-scale region of flow with a homogeneous temperature distribution. (interaction of laser radiation with matter. laser plasma)

Gladush, G G; Drobyazko, S V; Likhanskii, V V; Loboiko, A I; Senatorov, Yu M [State Research Center of Russian Federation 'Troitsk Institute for Innovation and Fusion Research', Troitsk, Moscow Region (Russian Federation)

1998-05-31T23:59:59.000Z

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


201

Convective Dynamo Simulation with a Grand Minimum  

E-Print Network [OSTI]

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...

Augustson, Kyle; Miesch, Mark; Toomre, Juri

2015-01-01T23:59:59.000Z

202

Stability of sunspots to convective motions. I. Adiabatic instability  

SciTech Connect (OSTI)

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

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

1989-07-01T23:59:59.000Z

203

The multiple vortex nature of tropical cyclogenesis  

E-Print Network [OSTI]

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

Sippel, Jason Allen

2005-02-17T23:59:59.000Z

204

Midlevel ventilation's constraint on tropical cyclone intensity  

E-Print Network [OSTI]

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

Tang, Brian Hong-An

2010-01-01T23:59:59.000Z

205

Dynamo Action in the Solar Convection Zone and Tachocline: Pumping and Organization of Toroidal Fields  

E-Print Network [OSTI]

We present the first results from three-dimensional spherical shell simulations of magnetic dynamo action realized by turbulent convection penetrating downward into a tachocline of rotational shear. This permits us to assess several dynamical elements believed to be crucial to the operation of the solar global dynamo, variously involving differential rotation resulting from convection, magnetic pumping, and amplification of fields by stretching within the tachocline. The simulations reveal that strong axisymmetric toroidal magnetic fields (about 3000 G in strength) are realized within the lower stable layer, unlike in the convection zone where fluctuating fields are predominant. The toroidal fields in the stable layer possess a striking persistent antisymmetric parity, with fields in the northern hemisphere largely of opposite polarity to those in the southern hemisphere. The associated mean poloidal magnetic fields there have a clear dipolar geometry, but we have not yet observed any distinctive reversals or latitudinal propagation. The presence of these deep magnetic fields appears to stabilize the sense of mean fields produced by vigorous dynamo action in the bulk of the convection zone.

Matthew Browning; Mark S. Miesch; Allan Sacha Brun; Juri Toomre

2006-09-06T23:59:59.000Z

206

The Ratio of Helium- to Hydrogen-Atmosphere White Dwarfs: Direct Evidence for Convective Mixing  

E-Print Network [OSTI]

We determine the ratio of helium- to hydrogen-atmosphere white dwarf stars as a function of effective temperature from a model atmosphere analysis of the infrared photometric data from the Two Micron All Sky Survey combined with available visual magnitudes. Our study surpasses any previous analysis of this kind both in terms of the accuracy of the Teff determinations as well as the size of the sample. We observe that the ratio of helium- to hydrogen-atmosphere white dwarfs increases gradually from a constant value of ~0.25 between Teff = 15,000 K and 10,000 K to a value twice as large in the range 10,000 > Teff > 8000 K, suggesting that convective mixing, which occurs when the bottom of the hydrogen convection zone reaches the underlying convective helium envelope, is responsible for this gradual transition. The comparison of our results with an approximate model used to describe the outcome of this convective mixing process implies hydrogen mass layers in the range log M_H/M_tot = -10 to -8 for about 15% of the DA stars that survived the DA to DB transition near Teff ~ 30,000 K, the remainder having presumably more massive layers above log M_H/M_tot ~ -6.

P. -E. Tremblay; P. Bergeron

2007-10-04T23:59:59.000Z

207

Meridional Circulation in Solar and Stellar Convection Zones  

E-Print Network [OSTI]

We present a series of 3-D nonlinear simulations of solar-like convection, carried out using the Anelastic Spherical Harmonic (ASH) code, that are designed to isolate those processes that drive and shape meridional circulations within stellar convection zones. These simulations have been constructed so as to span the transition between solar-like differential rotation (fast equator/slow poles) and ``anti-solar' differential rotation (slow equator/fast poles). Solar-like states of differential rotation, arising when convection is rotationally constrained, are characterized by a very different convective Reynolds stress than anti-solar regimes, wherein convection only weakly senses the Coriolis force. We find that the angular momentum transport by convective Reynolds stress plays a central role in establishing the meridional flow profiles in these simulations. We find that the transition from single-celled to multi-celled meridional circulation profiles in strong and weak regimes of rotational constraint is lin...

Featherstone, Nicholas A

2015-01-01T23:59:59.000Z

208

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

SciTech Connect (OSTI)

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.

Ma, Hsi-Yen; Mechoso, C. R.; Xue, Yongkang; Xiao, Heng; Neelin, David; Ji, Xuan

2013-11-15T23:59:59.000Z

209

The Mid-Latitude Continental Convective Clouds Experiment (MC3E)  

SciTech Connect (OSTI)

The Midlatitude Continental Convective Cloud 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 Atmospheric Radition Measurement Program and the National Aeronautics and Space Administration's (NASA) Global Precipitation Measurement (GPM) mission Ground Validation program. The Intensive Observation Period 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 observations over land that have never before been available. Several different components of convective processes tangible to the convective parameterization problem are targeted such as, pre-convective environment and convective initiation, updraft / downdraft dynamics, condensate transport and detrainment, precipitation and cloud microphysics, influence on the environment and radiation and a detailed description of the large-scale forcing. MC3E will use a new multi-scale observing strategy with the participation of a network of distributed sensors (both passive and active). The approach is to document in 3-D not only the full spectrum of precipitation rates, but also clouds, winds and moisture in an attempt to provide a holistic view of convective clouds and their feedback with the environment. A goal is to measure cloud and precipitation transitions and environmental quantities that are important for satellite retrieval algorithms, convective parameterization in large-scale models and cloud-resolving model simulations. This will be accomplished through the deployment of several different elements that complement the existing (and soon to become available) ARM facilities: a network of radiosonde stations, NASA scanning multi-frequency/parameter radar systems at three different frequencies (Ka/Ku/S), high-altitude remote sensing and in situ aircraft, wind profilers and a network of surface disdrometers. In addition to these special MC3E instruments, there will be important new instrumentation deployed by DOE at the ARM site including: 3 networked scanning X-band radar systems, a C-band scanning radar, a dual wavelength (Ka/W) scanning cloud radar, a Doppler lidar and upgraded vertically pointing millimeter cloud radar (MMCR) and micropulse lidar (MPL).To fully describe the properties of precipitating cloud systems, both in situ and remote sensing airborne observations are necessary. The NASA GPM-funded University of North Dakota (UND) Citation will provide in situ observations of precipitation-sized particles, ice freezing nuclei and aerosol concentrations. As a complement to the UND Citation's in situ observations, the NASA ER-2 will provide a high altitude satellite simulator platform that carrying a Ka/Ku band radar and passive microwave radiometers (10-183 GHZ).

Petersen,W.; Jensen,M.; Genio, A. D.; Giangrande, S.; Heymsfield, A.; Heymsfield, G.; Hou, A.; Kollias, P.; Orr, B.; Rutledge, S.; Schwaller, M.; Zipser, E.

2010-03-15T23:59:59.000Z

210

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

E-Print Network [OSTI]

Influence of the tropical Atlantic versus the tropical Pacific on Caribbean rainfall Michael A; published 20 September 2002. [1] The Caribbean rainfall season runs from May through November, with positive anomalies over a narrow latitudinal band (0¬į¬≠20¬įN) being associated with enhanced Caribbean

211

Aquatic Botany 76 (2003) 299315 Phosphorus uptake kinetics of a dominant tropical  

E-Print Network [OSTI]

Laboratory, Biological Sciences Department, Florida Atlantic University, 777 Glades Road, Boca Raton, FL; Morse et al., 1987; Fourqurean et al., 1993; Jensen et al., 1998; Koch et al., 2001), with some notable in the observed P-limited growth of some tropical seagrass species (Short et al., 1985; Short, 1987; Powell et al

Koch-Rose, Marguerite

212

Antisymmetric polar modes of thermal convection in rotating fluid spherical shells at high Taylor numbers  

E-Print Network [OSTI]

of the liquid sodium ( = 0.01). For the first time, it is shown that at very high Taylor numbers the first numbers: 47.15.-x, 47.20.-k Electronic address: sanchez@fa.upc.edu Electronic address: marta@fa.upc by the properties of convection. The large-scale zonal winds observed in the surface of Jupiter at mid- and low

S√°nchez, Juan

213

Interactions of tropical synoptic-scale features as viewed from satellite  

E-Print Network [OSTI]

University Chair of Advisory Committee: Dr. James P. McGuirk Tropical synoptic features ? a hypothesized periodic 12 d oscillation over Central America and a 2800 km eastward propagating wave over the eastern Pacific ? are examined in OLR and TOVS... satellite observations. Their interactions with each other, with tropical plumes and intraseasonal oscil- lations are found to be weak. Time series analysis of the area-averaged (140 -40 W and 35'N-35 S) daily OLR for 1984 revealed a persistent 12 d...

Winton, Susan Elizabeth

1991-01-01T23:59:59.000Z

214

Ocean dynamics and thermodynamics in the tropical Indo- Pacific region  

E-Print Network [OSTI]

The shortwave radiation entering the ocean mixed layer wasocean mixed layer in various ways: convective cells block the incoming solar radiationradiation (71%) that result from anomalous MJO convection. An exception is in the central Indian Ocean and

Drushka, Kyla

2011-01-01T23:59:59.000Z

215

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcal Documentation(AVIRIS) ProductsAirborne Visible/Infrared Imaging SpectrometerAlgorithmProductsConvective

216

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

E-Print Network [OSTI]

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

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

2006-01-01T23:59:59.000Z

217

Seasonal shift in the foraging niche of a tropical avian resident: resource competition at work?  

E-Print Network [OSTI]

and migrant birds in Campeche, Mexico. Tropical Ecology 22:a dry tropical forest in Campeche, Mexico and found that

Jedlicka, J A; Greenberg, R; Perfecto, I; Philpottt, S M; Dietsch, T V

2006-01-01T23:59:59.000Z

218

Evaluating the Representation and Impact of Convective Processes in the NCARís Community Climate System Model  

SciTech Connect (OSTI)

Convection and clouds affect atmospheric temperature, moisture and wind fields through the heat of condensation and evaporation and through redistributions of heat, moisture and momentum. Individual clouds have a spatial scale of less than 10 km, much smaller than the grid size of several hundred kilometers used in climate models. Therefore the effects of clouds must be approximated in terms of variables that the model can resolve. Deriving such formulations for convection and clouds has been a major challenge for the climate modeling community due to the lack of observations of cloud and microphysical properties. The objective of our DOE CCPP project is to evaluate and improve the representation of convection schemes developed by PIs in the NCAR (National Center for Atmospheric Research) Community Climate System Model (CCSM) and study its impact on global climate simulations.

Xiaoqing Wu

2008-07-31T23:59:59.000Z

219

Gravity Waves in Shear and Implications for Organized Convection  

E-Print Network [OSTI]

Gravity Waves in Shear and Implications for Organized Convection Samuel N. Stechmann Department, Los Angeles, CA 90095­1555. E-mail: stechmann@math.ucla.edu #12;ABSTRACT It is known that gravity, the gravity waves can create a more favorable environment on one side of preexisting convection than the other

Stechmann, Samuel N.

220

EXPERIMENTAL INVESTIGATION OF BOILING HEAT CONVECTION IN A FRACTURE  

E-Print Network [OSTI]

EXPERIMENTAL INVESTIGATION OF BOILING HEAT CONVECTION IN A FRACTURE A REPORT SUBMITTED between heat conduction and heat convection with boiling flow in a rock fracture. An experimental coefficient. This coefficient is the proportionality factor between the heat flux to a fracture surface

Stanford University

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


221

UNCORRECTED Grid geometry effects on convection in ocean climate models  

E-Print Network [OSTI]

UNCORRECTED PROOF Grid geometry effects on convection in ocean climate models: a conceptual study is the 12 improvement of convection parameterization schemes, but the question of grid geometry also plays to an at- 14 mosphere model. Such ocean climate models have mostly structured, coarsely resolved grids. 15

Kuhlbrodt, Till

222

FLUCTUATIONS NEAR THE CONVECTIVE INSTABILITY IN A CHOLESTERIC LIQUID CRYSTAL  

E-Print Network [OSTI]

. For sufficiently strong heating, it is pos- sible for the buoyancy force to overcome the vis- cous shear forces convective pour une certaine valeur critique. A cause du couplage de modes induit par la force extťrieure, la, drives the system into convective instability. It is found that, because of the mode coupling induced

Boyer, Edmond

223

Drainage induced convection rolls in foams (revised version)  

E-Print Network [OSTI]

, where soap solution is added to the foam at constant flow rate, the irregular motion in the beer glass results for convection in quasi two-dimensional foams (monolayers of bubbles between two glass platesDrainage induced convection rolls in foams (revised version) S. Hutzler, S.J. Cox*, E. Janiaud

Cox, Simon

224

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

SciTech Connect (OSTI)

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.

Chen, Shu-Hua; Liu, Yi-Chin

2014-10-27T23:59:59.000Z

225

WMO/CAS/WWW SEVENTH INTERNATIONAL WORKSHOP ON TROPICAL CYCLONES  

E-Print Network [OSTI]

. As outlined by Dunkerton et al. (2009, hereafter DMW09), the problem of tropical cyclogenesis in the real

Smith, Roger K.

226

Meridional circulation dynamics from 3D MHD global simulations of solar convection  

E-Print Network [OSTI]

The form of the solar meridional circulation is a very important ingredient for mean field flux transport dynamo models. Yet a shroud of mystery still surrounds this large-scale flow, given that its measurement using current helioseismic techniques is challenging. In this work we use results from 3D global simulations of solar convection to infer the dynamical behavior of the established meridional circulation. We make a direct comparison between the meridional circulation that arises in these simulations and the latest observations. Based on our results we argue that there should be an equatorward flow at the base of the convection zone at mid latitudes, below the current maximum depth helioseismic measures can probe (0.75 R). We also provide physical arguments to justify this behaviour. The simulations indicate that the meridional circulation undergoes substantial changes in morphology as the magnetic cycle unfolds. We close by discussing the importance of these dynamical changes for current methods of obse...

Passos, Dario; Miesch, Mark

2015-01-01T23:59:59.000Z

227

ARM - Midlatitude Continental Convective Clouds - Single Column Model Forcing (xie-scm_forcing)  

SciTech Connect (OSTI)

The constrained variational objective analysis approach described in Zhang and Lin [1997] and Zhang et al. [2001]was used to derive the large-scale single-column/cloud resolving model forcing and evaluation data set from the observational data collected during Midlatitude Continental Convective Clouds Experiment (MC3E), which was conducted during April to June 2011 near the ARM Southern Great Plains (SGP) site. The analysis data cover the period from 00Z 22 April - 21Z 6 June 2011. The forcing data represent an average over the 3 different analysis domains centered at central facility with a diameter of 300 km (standard SGP forcing domain size), 150 km and 75 km, as shown in Figure 1. This is to support modeling studies on various-scale convective systems.

Xie, Shaocheng; McCoy, Renata; Zhang, Yunyan

2012-10-25T23:59:59.000Z

228

ARM - Midlatitude Continental Convective Clouds - Single Column Model Forcing (xie-scm_forcing)  

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

The constrained variational objective analysis approach described in Zhang and Lin [1997] and Zhang et al. [2001]was used to derive the large-scale single-column/cloud resolving model forcing and evaluation data set from the observational data collected during Midlatitude Continental Convective Clouds Experiment (MC3E), which was conducted during April to June 2011 near the ARM Southern Great Plains (SGP) site. The analysis data cover the period from 00Z 22 April - 21Z 6 June 2011. The forcing data represent an average over the 3 different analysis domains centered at central facility with a diameter of 300 km (standard SGP forcing domain size), 150 km and 75 km, as shown in Figure 1. This is to support modeling studies on various-scale convective systems.

Xie, Shaocheng; McCoy, Renata; Zhang, Yunyan

229

Magnetic Inhibition of Convection and the Fundamental Properties of Low-Mass Stars. I. Stars with a Radiative Core  

E-Print Network [OSTI]

Magnetic fields are hypothesized to inflate the radii of low-mass stars---defined as less massive than 0.8 solar masses---in detached eclipsing binaries (DEBs). We investigate this hypothesis using the recently introduced magnetic Dartmouth stellar evolution code. In particular, we focus on stars thought to have a radiative core and convective outer envelope by studying in detail three individual DEBs: UV Psc, YY Gem, and CU Cnc. The results suggest that the stabilization of thermal convection by a magnetic field is a plausible explanation for the observed model-radius discrepancies. However, surface magnetic field strengths required by the models are significantly stronger than those estimated from the observed coronal X-ray emission. Agreement between model predicted surface magnetic field strengths and those inferred from X-ray observations can be found by assuming that the magnetic field sources its energy from convection. This approach makes the transport of heat by convection less efficient and is akin ...

Feiden, Gregory A

2013-01-01T23:59:59.000Z

230

Species Loss and Aboveground Carbon Storage in a Tropical Forest  

E-Print Network [OSTI]

of tropical tree species on carbon storage by simulating 18 possible extinction scenarios within a well-studied 50-hectare tropical forest plot in Panama, which contains 227 tree species. Among extinction as well as the size and longevity of tropical trees. Instead, we simulated species extinctions

Bunker, Daniel E.

231

Investigating Tropical Deforestation Using Two-Stage Spatially Misaligned  

E-Print Network [OSTI]

Investigating Tropical Deforestation Using Two-Stage Spatially Misaligned Regression Models Deepak Deforestation in the tropics has been a major concern in conservationscience for more than 20 years. Estimates of tropical deforestation over the past few decades have shown an alarming accelerationin forest lost. Concern

Silander Jr., John A.

232

ONGOING RESEARCH PROJECTS Model of tropical forest structure and dynamics  

E-Print Network [OSTI]

ONGOING RESEARCH PROJECTS Model of tropical forest structure and dynamics There is a need canopy structure and partitions dynamic rates for a tropical forest on Barro Colorado Island (BCI structure and partitions dynamic rates in a tropical forest. In Review. Journal of Ecology. #12;PPA model

Hill, Jeffrey E.

233

Impacts of Microphysical Scheme on Convective and Stratiform Characteristics in Two High Precipitation Squall Line Events  

SciTech Connect (OSTI)

This study investigates the impact of snow, graupel, and hail processes on the simulated squall lines over the Southern Great Plains in the United States. Weather Research and Forecasting (WRF) model is used to simulate two squall line events in May 2007, and the results are validated against radar and surface observations in Oklahoma. Several microphysics schemes are tested in this study, including WRF 5-Class Microphysics Scheme (WSM5), WRF 6-Class Microphysics Scheme (WSM6), Goddard Three Ice scheme (Goddard 3-ice) with graupel, Goddard Two Ice scheme (Goddard 2-ice), and Goddard 3-ice hail scheme. The simulated surface precipitation is sensitive to the microphysics scheme, and especially to whether graupel or hail category is included. All of the three ice (3-ice) schemes overestimated the total precipitation, within which WSM6 has the highest overestimation. Two ice (2-ice) schemes, missing a graupel/hail category, produced less total precipitation than 3-ice schemes. By applying a radar-based convective/stratiform partitioning algorithm, we find that by including the graupel/hail processes, there is an increase in areal coverage, precipitation intensity, updraft and downdraft intensity in convective region and a reduction of areal coverage and its precipitation intensity in stratiform region. For vertical structures, all the bulk schemes, especially 2-ice schemes, have the highest reflectivity located at upper levels (~8 km), which is unrealistic compared to observations. In addition, this study shows the radar-based convective/stratiform partitioning algorithm can reasonably identify WRF simulated precipitation, wind and microphysics fields in both convective and stratiform regions.

Wu, Di; Dong, Xiquan; Xi, Baike; Feng, Zhe; Kennedy, Aaron; Mullendore, Gretchen; Gilmore, Matthew; Tao, Wei-Kuo

2013-10-04T23:59:59.000Z

234

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

E-Print Network [OSTI]

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

Davis, James Gregory

1979-01-01T23:59:59.000Z

235

Carbon dioxide measurements in tropical east African biomes  

SciTech Connect (OSTI)

From January 1977 through May 1978 atmospheric CO/sub 2/ concentrations were measured hourly and/or continuously at bimonthly intervals over periods varying from 5 to 8 days at 10 different locations in Kenya, East Africa. During each of these periods, at least two, and in some cases five, vertical profile measurements of CO/sub 2/ concentrations were conducted above different biomes. A large diurnal CO/sub 2/ periodicity was observed over land, with daytime drawdowns to 322 ppm and nighttime buildups to more than 400 ppm observed in savannah regions. In and around tropical rain forests, drawdowns to 310 ppm and buildups to more than 400 ppm were regularly observed. On the higher reaches of Mount Kenya, the diurnal CO/sub 2/ cycle was considerably reduced in amplitude, with variations in the range of 2-6 ppm throughout the 16-month study period. On sunny days, the drawdown of CO/sub 2/ was measurable to heights of at least 4000 m above ground level. Other CO/sub 2/ measurements in air over the Indian Ocean (to distances of up to 450 km upwind of the coast) produced fairly consistent concentrations of about 328.5 ppm which did not fluctuate diurnally. The weekly mean CO/sub 2/ concentrations over Kenya appear to have a bimodal structure, with minima occurring in July and January. On the basis of the data collected during the study it appears likely that regular observations at a high-altitude station on Mount Kenya, either with flask sampling or continuous analyzer measurements, are likely to yield data useful for estimates of CO/sub 2/ concentration backgrounds and trends. Also, there is strong evidence that Mount Kenya would be a good location to measure large-scale interhemispheric CO/sub 2/ exchanges and provide a unique base from which to study the effects of the tropical biome on biogeochemical phenomena. 20 references, 12 figures, 2 tables.

Schnell, R.C.; Odh, S.A.; Njau, L.N.

1981-06-20T23:59:59.000Z

236

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

E-Print Network [OSTI]

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

Foxcroft, Llewellyn C.; Richardson, David M.; RejmŠnek, Marcel; Pyöek, Petr

2010-01-01T23:59:59.000Z

237

Divergent subcritical convection in magnetized plasma from asymmetric sourcing  

SciTech Connect (OSTI)

Asymmetric particle and heat sourcing in a plasma confined in a closed magnetic field line configuration results in convection cells, as is well known. This phenomenon occurs even if the sourcing on average produces density and temperature profiles that are subcritical, i.e., magnetohydrodynamically stable to interchange modes. Such subcritical convection is expected to be small compared to the convection from supercritical driving for which the system is interchange unstable. The ratio of subcritical to supercritical convection is expected to scale as the inverse Reynolds numbers (for large Reynolds numbers). It is shown that this ratio is, in fact, considerably larger. As marginal stability is approached, the subcritical convection grows from very small to almost the unstable convection size, i.e., of order unity. This effect may be similar to why a driven, damped harmonic oscillator increases in amplitude as resonance is approached. A numerical simulation is done to demonstrate this effect. It is also shown that transport from the large convection can be substantial.

Adler, D.T.; Hassam, A.B. [Department of Physics, University of Maryland, College Park, Maryland 20742 (United States)

2005-06-15T23:59:59.000Z

238

Climate Science: Tropical Expansion by Ocean Swing  

SciTech Connect (OSTI)

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.

Lu, Jian

2014-04-01T23:59:59.000Z

239

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

E-Print Network [OSTI]

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

Colonius, Tim

240

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

E-Print Network [OSTI]

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

Guo, Zhixiong "James"

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


241

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

E-Print Network [OSTI]

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

Firoozabadi, Abbas

242

Chaotic mean wind in turbulent thermal convection and long-term correlations in solar activity  

E-Print Network [OSTI]

It is shown that correlation function of the mean wind velocity in a turbulent thermal convection (Rayleigh number $Ra \\sim 10^{11}$) exhibits exponential decay with a very long correlation time, while corresponding largest Lyapunov exponent is certainly positive. These results together with the reconstructed phase portrait indicate presence of a chaotic component in the examined mean wind. Telegraph approximation is also used to study relative contribution of the chaotic and stochastic components to the mean wind fluctuations and an equilibrium between these components has been studied. Since solar activity is based on the thermal convection processes, it is reasoned that the observed solar activity long-term correlations can be an imprint of the mean wind chaotic properties. In particular, correlation function of the daily sunspots number exhibits exponential decay with a very long correlation time and corresponding largest Lyapunov exponent is certainly positive, also relative contribution of the chaotic and stochastic components follows the same pattern as for the convection mean wind.

A. Bershadskii

2009-12-25T23:59:59.000Z

243

Solar dynamo models with alpha-effect and turbulent pumping from local 3D convection calculations  

E-Print Network [OSTI]

(abridged) Results from kinematic solar dynamo models employing alpha-effect and turbulent pumping from local convection calculations are presented. We estimate the magnitude of these effects to be around 2-3 m/s. The rotation profile of the Sun as obtained from helioseismology is applied. We obtain an estimate of the ratio of the two induction effects, C_alpha/C_Omega \\approx 10^-3, which we keep fixed in all models. We also include a one-cell meridional circulation pattern having a magnitude of 10-20 m/s near the surface and 1-2 m/s at the bottom of the convection zone. The model essentially represents a distributed turbulent dynamo, as the alpha-effect is nonzero throughout the convection zone, although it concentrates near the bottom of the convection zone obtaining a maximum around 30 degrees of latitude. Turbulent pumping of the mean fields is predominantly down- and equatorward. We find that, when all these effects are included in the model, it is possible to correctly reproduce many features of the solar activity cycle, namely the correct equatorward migration at low latitudes and the polar branch at high latitudes, and the observed negative sign of B_r B_phi. Although the activity clearly shifts towards the equator in comparison to previous models due to the combined action of the alpha-effect peaking at midlatitudes, meridional circulation and latitudinal pumping, most of the activity still occurs at too high latitudes (between 5-60 degrees). Other problems include the relatively narrow parameter space within which the preferred solution is dipolar (A0), and the somewhat too short cycle lengths of the solar-type solutions. The role of the surface shear layer is found to be important only in the case where the alpha-effect has an appreciable magnitude near the surface.

P. J. Kšpylš; M. J. Korpi; I. Tuominen

2006-06-05T23:59:59.000Z

244

atmospheric convective boundary: Topics by E-print Network  

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

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

245

Effects of aerosols on deep convective cumulus clouds  

E-Print Network [OSTI]

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

Fan, Jiwen

2009-05-15T23:59:59.000Z

246

Experimental Investigation of Natural Convection in Trombe Wall Systems  

E-Print Network [OSTI]

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...

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

2006-01-01T23:59:59.000Z

247

Rotation of the solar convection zone from helioseismology  

E-Print Network [OSTI]

Helioseismology has provided very detailed inferences about rotation of the solar interior. Within the convection zone the rotation rate roughly shares the latitudinal variation seen in the surface differential rotation. The transition to the nearly uniformly rotating radiative interior takes place in a narrow tachocline, which is likely important to the operation of the solar magnetic cycle.The convection-zone rotation displays zonal flows, regions of slightly more rapid and slow rotation, extending over much of the depth of the convection zone and converging towards the equator as the solar cycle progresses. In addition, there is some evidence for a quasi-periodic variation in rotation, with a period of around 1.3 yr, at the equator near the bottom of the convection zone.

J. Christensen-Dalsgaard

2006-10-31T23:59:59.000Z

248

Survey and evaluation of techniques to augment convective heat transfer  

E-Print Network [OSTI]

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 ...

Bergles A. E.

1965-01-01T23:59:59.000Z

249

VARIATION OF STELLAR ENVELOPE CONVECTION AND OVERSHOOT WITH METALLICITY  

SciTech Connect (OSTI)

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

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

2013-04-10T23:59:59.000Z

250

Land-atmosphere interaction and radiative-convective equilibrium  

E-Print Network [OSTI]

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

Cronin, Timothy (Timothy Wallace)

2014-01-01T23:59:59.000Z

251

Interaction between surface and atmosphere in a convective boundary layer /  

E-Print Network [OSTI]

heat, and thermal conductivity of the ground and grid sizegrid was stretched uniformly to 0.1 m resolution. The heatheat flux) are friction velocity and convective velocity respectively. The grid

Garai, Anirban

2013-01-01T23:59:59.000Z

252

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

SciTech Connect (OSTI)

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.

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

1981-04-01T23:59:59.000Z

253

Possible solar cycle variations in the convection zone  

E-Print Network [OSTI]

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

Sarbani Basu; H. M. Antia

2000-01-26T23:59:59.000Z

254

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

E-Print Network [OSTI]

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

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

2013-01-01T23:59:59.000Z

255

Thermal effects of Kohout convection in the Bahamas and Florida  

SciTech Connect (OSTI)

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

Simms, M.A.

1985-01-01T23:59:59.000Z

256

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

E-Print Network [OSTI]

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

Droegemeier, Kelvin K.

257

Dynamic Transitions of Surface Tension Driven Convection  

E-Print Network [OSTI]

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

Henk Dijkstra; Taylan Sengul; Shouhong Wang

2011-05-05T23:59:59.000Z

258

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

E-Print Network [OSTI]

. REFERENCES. . . . . VITA. . . 116 119 125 LIST OF FIGURES FIGURE I Typhoon Oscar 85 GHz PCT iield at 2117 UTC 15 September 1995. . . . , Page 2 Correlations between 0-1' radius PCT parameters and hurricane/typhoon intensity at the time of SSM... miniinum PCT and lightning in Hurricane Barbara. . 79 46 Typhoon Oscar best track, 12 IJTC 7 September - 0 UTC 18 September 1995. . 81 47 Oscar 85 GHz PCT field at 2014 UTC 12 September 1995. . . . . . 48 Oscar 85 GHz PCT field at 2112 IJTC 13 September...

Cecil, Daniel Joseph

1997-01-01T23:59:59.000Z

259

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

E-Print Network [OSTI]

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

Francis J. Robinson; Kwing L. Chan

2000-11-21T23:59:59.000Z

260

UDC 551.613.1:551.511.33:551.509.313(213) Response of the Tropical Atmosphere  

E-Print Network [OSTI]

study of the tropical atmosphere. From analyses of wind data in the lower stratosphere over considers lateral coupling with higher latitude energy sources as the most important driving force are of an observational nature. Kidson et al. (1969) studied the statistical properties of both the steady and transient

Webster, Peter J.

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


261

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

Open Energy Info (EERE)

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

262

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

E-Print Network [OSTI]

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

Paris-Sud XI, Université de

263

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

Open Energy Info (EERE)

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

264

australian tropical savannas: Topics by E-print Network  

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

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

265

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

E-Print Network [OSTI]

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

Olson, Mark

266

Carbon sequestration potential of tropical pasture compared with afforestation in Panama  

E-Print Network [OSTI]

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

Potvin, Catherine

267

Efficient small-scale dynamo in solar convection zone  

E-Print Network [OSTI]

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

Hotta, H; Yokoyama, T

2015-01-01T23:59:59.000Z

268

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

E-Print Network [OSTI]

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

Rafter, Patrick Anthony

2009-01-01T23:59:59.000Z

269

E-Print Network 3.0 - ambiente tropical um Sample Search Results  

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

Summary: and composition of fruit-feeding butterflies in tropical plantation forests. Biodiversity and Conservation. DOI... for biodiversity conservation in the tropics. Tree...

270

ARM - Midlatitude Continental Convective Clouds (comstock-hvps)  

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

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.

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

271

Isotopic composition of water in the tropical tropopause layer in cloudresolving simulations of an idealized tropical circulation  

E-Print Network [OSTI]

that both the sublimation of relatively enriched ice associated with deep convection and fractionation role in the climate and chemistry of the stratosphere and also of the Earth as a whole [e.g., Forster convection through the injection and subsequent sublimation of ice [e.g., Corti et al., 2008], dehydration

Romps, David M.

272

The iron nutrition of tropical foliage plants  

E-Print Network [OSTI]

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

Lang, Harvey Joe

1986-01-01T23:59:59.000Z

273

ARM - Lesson Plans: Tropical Western Pacific  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc Documentation RUC : XDCResearch Related InformationAcid RainThe Pacific and El Ni√ĪoTropical

274

Tropical Cloud Life Cycle and Overlap Structure  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched Ferromagnetism in Layered NbS2TopoPortalBRDF Effects inHeterogeneous andTropical

275

Chapter Number1 Biomass Prediction in Tropical Forests:2  

E-Print Network [OSTI]

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

Paris-Sud XI, Université de

276

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

E-Print Network [OSTI]

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

G. L. Litvinov

2005-07-01T23:59:59.000Z

277

Proximate Population Factors and Deforestation in Tropical Agricultural Frontiers  

E-Print Network [OSTI]

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

Lopez-Carr, David

278

Carbon accumulation of tropical peatlands over millennia: a modeling approach  

E-Print Network [OSTI]

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

279

Climate change and tropical biodiversity: a new focus  

E-Print Network [OSTI]

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

Wisenden, Brian D.

280

TROPICAL CYCLONE RESEARCH REPORT TCRR 2: 131 (2013)  

E-Print Network [OSTI]

circulation (e.g., Marks and Shay 1998). There have been considerable advances in computer technology overTROPICAL CYCLONE RESEARCH REPORT TCRR 2: 1­31 (2013) Meteorological Institute Ludwig Maximilians University of Munich Paradigms for tropical cyclone intensification Michael T. Montgomerya 1 and Roger K

Smith, Roger K.

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


281

Hybrid coupled modeling of the tropical Pacific using neural networks  

E-Print Network [OSTI]

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

Hsieh, William

282

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

E-Print Network [OSTI]

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

Khaykin, S.

283

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

E-Print Network [OSTI]

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. ...

Bergles A. E.

1962-01-01T23:59:59.000Z

284

Severe convection and lightning in subtropical South America By Kristen L. Rasmussen1  

E-Print Network [OSTI]

1 Severe convection and lightning in subtropical South America of the seasonal, diurnal, and extreme storm-related lightning in South America. · Preference for hail radar and radiometer data show that subtropical South America has the world's deepest convective

Houze Jr., Robert A.

285

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

E-Print Network [OSTI]

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

Paparella, Francesco

286

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

E-Print Network [OSTI]

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

Reuter, Martin

287

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

E-Print Network [OSTI]

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

Boyer, Edmond

288

Evolution du contenu physique 1. Nouveau bloc couche limite convection nuages (nouvelle physique)  

E-Print Network [OSTI]

Evolution du contenu physique 1. Nouveau bloc couche limite ­ convection ­ nuages (nouvelle physique) ON DISPOSE D'UN NOUVEAU CADRE DE TRAVAIL. ?? - Convection /relief (Jean-Yves Grandpeix, Jingmei Yu, Alain Lahelec) ++ - glace dans la convection (Arnaud Jam, Jean-Yves Grandpeix) ?? - Modèle micro-physique

Madeleine, Jean-Baptiste

289

Life Cycle of a Mesoscale Circular Gust Front Observed by a C-Band Doppler Radar in West Africa  

E-Print Network [OSTI]

On 10 July 2006, during the Special Observation Period (SOP) of the African Monsoon Multidisciplinary Analysis (AMMA) campaign, a small convective system initiated over Niamey and propagated westward in the vicinity of ...

Lothon, Marie

290

A numerical study of convection with an ambient wind field  

E-Print Network [OSTI]

. The citations on the following pages follow the style of the Journal of the Atmos heric Sciences. Orville (1968) constructed a convective model based on the same equations as those used by Assi. He concerned himself with the development of cumulus clouds over...

Cottrell, Kit Garfield

1970-01-01T23:59:59.000Z

291

EFFECTS OF SURFACE DEPRESSION AND CONVECTION IN GTA WELDING  

E-Print Network [OSTI]

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

Eagar, Thomas W.

292

Modeling thermal convection in supradetachment basins: example from western Norway  

E-Print Network [OSTI]

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

Andersen, Torgeir Bj√łrge

293

Convection venting lensed reflector-type compact fluorescent lamp system  

DOE Patents [OSTI]

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.

Pelton, B.A.; Siminovitch, M.

1997-07-29T23:59:59.000Z

294

Sparse grid collocation schemes for stochastic natural convection problems  

E-Print Network [OSTI]

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

Zabaras, Nicholas J.

295

Does convective aggregation need to be represented in cumulus parameterizations?  

E-Print Network [OSTI]

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

296

Drift Natural Convection and Seepage at the Yucca Mountain Repository  

E-Print Network [OSTI]

that the heat and mass transfer of the open in-drift can beheat transfer processes[26, 33], in both the fractured rock and the openheat transfer coefficient, hc eff , as described in Appendix A.2.1. For our case, modeling convection in open

Halecky, Nicholaus Eugene

2010-01-01T23:59:59.000Z

297

NATURAL CONVECTION OF SUBCOOLED LIQUID NITROGEN IN A VERTICAL CAVITY  

E-Print Network [OSTI]

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

Chang, Ho-Myung

298

Feedback on vertical velocity. Rotation, convection, self-sustaining process.  

E-Print Network [OSTI]

Feedback on vertical velocity. Rotation, convection, self-sustaining process. Fabian Waleffe the mechanisms involved in the nonlinear feedback from u to v, yielding a self-sustaining process for shear flows feedback from the streak instability into the rolls sufficient to lead to a self-sustaining process

Lebovitz, Norman

299

Numerical analysis of binary fluid convection in extended systems  

E-Print Network [OSTI]

arising in the primary subcritical bifurcation. The dynamics triggered by Eckhaus instability is discussed mixtures. For such mixtures, the onset of convection is via a subcritical Hopf bifurcation that gives rise of S. In the case of the experiment reported in [2] a S = -0.257 water-ethanol mixture is used. A final

Batiste, Oriol

300

Predicting flow reversals in chaotic natural convection using data assimilation  

E-Print Network [OSTI]

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

Danforth, Chris

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


301

OSCILLATORY FLOW FORCED CONVECTION IN MICRO HEAT SPREADERS  

E-Print Network [OSTI]

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

Beskok, Ali

302

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

E-Print Network [OSTI]

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

Sobel, Adam

303

Transport of Magnetic Fields in Convective, Accreting Supernova Cores  

E-Print Network [OSTI]

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

Christopher Thompson; Norman Murray

2001-05-24T23:59:59.000Z

304

A Comparison of Precipitation Forecast Skill between Small Convection-Allowing and Large Convection-Parameterizing Ensembles  

E-Print Network [OSTI]

A Comparison of Precipitation Forecast Skill between Small Convection- Allowing and Large Submitted to Weather and Forecasting in October 2008, Accepted in January 2009 * Corresponding author precipitation forecasts from a 5-member, 4-km grid-spacing (ENS4) and a 15-member, 20-km grid-spacing (ENS20

Droegemeier, Kelvin K.

305

Classical confinement and outward convection of impurity ions in the MST RFP  

SciTech Connect (OSTI)

Impurity ion dynamics measured with simultaneously high spatial and temporal resolution reveal classical ion transport in the reversed-field pinch. The boron, carbon, oxygen, and aluminum impurity ion density profiles are obtained in the Madison Symmetric Torus [R. N. Dexter et al., Fusion Technol. 19, 131 (1991)] using a fast, active charge-exchange-recombination-spectroscopy diagnostic. Measurements are made during improved-confinement plasmas obtained using inductive control of tearing instability to mitigate stochastic transport. At the onset of the transition to improved confinement, the impurity ion density profile becomes hollow, with a slow decay in the core region concurrent with an increase in the outer region, implying an outward convection of impurities. Impurity transport from Coulomb collisions in the reversed-field pinch is classical for all collisionality regimes, and analysis shows that the observed hollow profile and outward convection can be explained by the classical temperature screening mechanism. The profile agrees well with classical expectations. Experiments performed with impurity pellet injection provide further evidence for classical impurity ion confinement.

Kumar, S. T. A.; Den Hartog, D. J.; Mirnov, V. V.; Eilerman, S.; Nornberg, M.; Reusch, J. A.; Sarff, J. S. [Department of Physics, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States); Center for Magnetic Self-Organization in Laboratory and Astrophysical Plasmas, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States); Caspary, K. J.; Chapman, B. E.; Parke, E. [Department of Physics, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States); Magee, R. M. [Department of Physics, West Virginia University, Morgantown, WV 26506 (United States); Brower, D. L.; Ding, W. X.; Lin, L. [Department of Physics and Astronomy, University of California, Los Angeles, California 90095 (United States); Craig, D. [Physics Department, Wheaton College, Wheaton, Illinois 60187 (United States); Fiksel, G. [Center for Magnetic Self-Organization in Laboratory and Astrophysical Plasmas, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States); Laboratory for Laser Energetics, University of Rochester, Rochester, New York (United States)

2012-05-15T23:59:59.000Z

306

Using cloud resolving model simulations of deep convection to inform cloud parameterizations in large-scale models  

SciTech Connect (OSTI)

Cloud parameterizations in large-scale models struggle to address the significant non-linear effects of radiation and precipitation that arise from horizontal inhomogeneity in cloud properties at scales smaller than the grid box size of the large-scale models. Statistical cloud schemes provide an attractive framework to self-consistently predict the horizontal inhomogeneity in radiation and microphysics because the probability distribution function (PDF) of total water contained in the scheme can be used to calculate these non-linear effects. Statistical cloud schemes were originally developed for boundary layer studies so extending them to a global model with many different environments is not straightforward. For example, deep convection creates abundant cloudiness and yet little is known about how deep convection alters the PDF of total water or how to parameterize these impacts. These issues are explored with data from a 29 day simulation by a cloud resolving model (CRM) of the July 1997 ARM Intensive Observing Period at the Southern Great Plains site. The simulation is used to answer two questions: (a) how well can the beta distribution represent the PDFs of total water relative to saturation resolved by the CRM? (b) how can the effects of convection on the PDF be parameterized? In addition to answering these questions, additional sections more fully describe the proposed statistical cloud scheme and the CRM simulation and analysis methods.

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

2003-06-23T23:59:59.000Z

307

Testing a Coupled Global-limited-area Data Assimilation System Using Observations from the 2004 Pacific Typhoon Season  

E-Print Network [OSTI]

Tropical cyclone (TC) track and intensity forecasts have improved in recent years due to increased model resolution, improved data assimilation, and the rapid increase in the number of routinely assimilated observations over oceans. The data...

Holt, Christina

2012-10-19T23:59:59.000Z

308

OBSERVATIONS ON THE WEB AND BEHAVIOR OF WENDILGARDA SPIDERS  

E-Print Network [OSTI]

OBSERVATIONS ON THE WEB AND BEHAVIOR OF WENDILGARDA SPIDERS (ARANEAE: THERIDIOSOMATIDAE that theridiosomatids spin modified orb-webs, but only the web of the holarctic Theridiosoma gemmosum (C. L. Koch) has the unusual webs ofsome tropical theridio- somatid spiders that the senior author later identified

Mathis, Wayne N.

309

Quantifying global marine isoprene fluxes using MODIS chlorophyll observations  

E-Print Network [OSTI]

, with considerable spatial and temporal variability, resulting in a global annual total of 0.1 Tg C/yr. Air vegetation [Guenther et al., 1995], with the tropics responsible for most of the global annual total ($500 TgQuantifying global marine isoprene fluxes using MODIS chlorophyll observations Paul I. Palmer

Palmer, Paul

310

Southern Hemisphere Additional Ozonesondes (SHADOZ) 19982000 tropical ozone climatology  

E-Print Network [OSTI]

ozone record from Paramaribo, Surinam (6¬įN, 55¬įW) (also in SHADOZ) shows a marked contrast to southern tropical ozone because Surinam is often north of the Intertropical Convergence Zone (ITCZ). A more

Thompson, Anne

311

The Political Economy of Deforestation in the Tropics  

E-Print Network [OSTI]

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

Burgess, Robin

312

Commercial Building HVAC Energy Usage in Semi-Tropical Climates  

E-Print Network [OSTI]

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

Worbs, H. E.

1987-01-01T23:59:59.000Z

313

american tropical cyclone: Topics by E-print Network  

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

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

314

african tropical forests: Topics by E-print Network  

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

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

315

african tropical forest: Topics by E-print Network  

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

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

316

annual tropical cyclone: Topics by E-print Network  

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

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

317

Surface Fluxes and Tropical Intraseasonal Variability: a Reassessment  

E-Print Network [OSTI]

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

Ribes, Aurťlien

318

WMO/CAS/WWW SIXTH INTERNATIONAL WORKSHOP on TROPICAL CYCLONES  

E-Print Network [OSTI]

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

Colorado at Boulder, University of

319

General Macro-and Microphysical Properties of Deep Convective Clouds as Observed by MODIS  

E-Print Network [OSTI]

(Ramanathan et al. 1989; Harrison et al. 1990; Hartmann et al. 1992) using satellite data have shown that net radiative forcing for DCC systems on large scale is close to zero with large negative shortwave (SW) forcing canceling out large positive longwave (LW) forcing. Kiehl (1994) used a simple calculation to explain

Li, Zhanqing

320

Convective cell bands in the central and eastern United States as observed by radar  

E-Print Network [OSTI]

-68, 10 cm, 700 KW, Tinker APSE Oklahoma Data: 27-28 April 1955 Synoptic Situation At 2130C/27, a cold front lay 60 miles northwest of Tinker AFS (Fig. 2). An old prefrontal instability line is shown 100 miles to the southeast Streamline charts...: CFS 6B ~ 10 cm, 700 KM, Tinker AFBg Oklahoma Date: 20 anarch 1955 Synoptic Situation The 1530C surface chez't (Fig. 14) shows a cold front 70 miles northwest of Tinker AFB corresponding to the location of the call bend at this time on the 1530C...

Leach, Wayne

2012-06-07T23:59:59.000Z

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


321

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

E-Print Network [OSTI]

dynamics and predictability given the anomalously strong and long-lived nature of the circulation and the dense data set. The first part of this study explores the dynamics of this MCV through an in-depth analysis of data from the profiler network and BAMEX...

Hawblitzel, Daniel Patrick

2006-08-16T23:59:59.000Z

322

Using observations of deep convective systems to constrain atmospheric column absorption of solar radiation in the  

E-Print Network [OSTI]

column absorption of solar radiation (Acol) is a fundamental part of the Earth's energy cycle.e., the Acol values at both regions converge to the same value ($0.27 of the total incoming solar radiation to constrain atmospheric column absorption of solar radiation in the optically thick limit, J. Geophys. Res

Dong, Xiquan

323

Regional variation of convective structure at monsoon onset across South America inferred from TRMM observations.  

E-Print Network [OSTI]

??The variation of precipitation in South America is characterized by different mechanisms that both initiate and sustain precipitation. Analysis to characterize regional differences is doneÖ (more)

Barnhill, Richard

2010-01-01T23:59:59.000Z

324

Observations and Modeling of Shallow Convective Clouds: Implications for the Indirect Aerosol Effects  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLasDelivered¬ČPNG IHDR¬Ä√ćSolar Energy SystemsFebruary 7-8,March 8,8)Normal 27 1 54In

325

Dissipation Efficiency in Turbulent Convective Zones in Low Mass Stars  

E-Print Network [OSTI]

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

Kaloyan Penev; Dimitar Sasselov; Frank Robinson; Pierre Demarque

2009-09-26T23:59:59.000Z

326

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

E-Print Network [OSTI]

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

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

2007-01-01T23:59:59.000Z

327

COMPARING THE EFFECT OF RADIATIVE TRANSFER SCHEMES ON CONVECTION SIMULATIONS  

SciTech Connect (OSTI)

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

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

2012-11-10T23:59:59.000Z

328

Influence of geometry on natural convection in buildings  

SciTech Connect (OSTI)

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.

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

1985-01-01T23:59:59.000Z

329

Evolution of moisture convergence in a mesoscale convective complex  

E-Print Network [OSTI]

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

Bercherer, John Phillip

1990-01-01T23:59:59.000Z

330

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

E-Print Network [OSTI]

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

Paris-Sud XI, Université de

331

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

E-Print Network [OSTI]

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. ...

Sobel, Adam

332

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

SciTech Connect (OSTI)

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.

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

2012-11-01T23:59:59.000Z

333

A Comparison of Simulated Cloud Radar Output from the Multiscale Modeling Framework Global Climate Model with CloudSat Cloud Radar Observations  

SciTech Connect (OSTI)

Over the last few years a new type of global climate model (GCM) has emerged in which a cloud-resolving model is embedded into each grid cell of a GCM. This new approach is frequently called a multiscale modeling framework (MMF) or superparameterization. In this article we present a comparison of MMF output with radar observations from the NASA CloudSat mission, which uses a near-nadir-pointing millimeter-wavelength radar to probe the vertical structure of clouds and precipitation. We account for radar detection limits by simulating the 94 GHz radar reflectivity that CloudSat would observe from the high-resolution cloud-resolving model output produced by the MMF. Overall, the MMF does a good job of reproducing the broad pattern of tropical convergence zones, subtropical belts, and midlatitude storm tracks, as well as their changes in position with the annual solar cycle. Nonetheless, the comparison also reveals a number of model shortfalls including (1) excessive hydrometeor coverage at all altitudes over many convectively active regions, (2) a lack of low-level hydrometeors over all subtropical oceanic basins, (3) excessive low-level hydrometeor coverage (principally precipitating hydrometeors) in the midlatitude storm tracks of both hemispheres during the summer season (in each hemisphere), and (4) a thin band of low-level hydrometeors in the Southern Hemisphere of the central (and at times eastern and western) Pacific in the MMF, which is not observed by CloudSat. This band resembles a second much weaker ITCZ but is restricted to low levels.

Marchand, Roger T.; Haynes, J. M.; Mace, Gerald G.; Ackerman, Thomas P.; Stephens, Graeme L.

2009-01-13T23:59:59.000Z

334

Damping of Type I X-ray Burst Oscillations by Convection  

E-Print Network [OSTI]

I construct a simple model of the convective burning layer during a type I X-ray burst to investigate the effects convection has on the stability of the layer to nonradial oscillations. A linear perturbation analysis demonstrates that the region is stable to nonradial oscillations when energy transport is convection-dominated, but it is unstable when energy transport is radiation-dominated. Thus, efficient convection always dampens oscillations. These results may explain the nondetection of oscillations during the peak of some X-ray bursts.

Randall L. Cooper

2008-03-26T23:59:59.000Z

335

E-Print Network 3.0 - axially focusing convection Sample Search...  

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

wall. The results show that the laminar forced convective heat transfer inside the tube never Source: Zhang, Yuwen - Department of Mechanical and Aerospace Engineering,...

336

Survival and activity of Streptococcus faecalis and Escherichia coli in petroleum-contaminated tropical marine waters  

SciTech Connect (OSTI)

The in situ survival and activity of Streptococcus faecalis and Escherichia coli were studied using membrane diffusion chambers in tropical marine waters receiving oil refinery effluents. Protein synthesis, DNA synthesis, respiration or fermentation, INT reduced per cell, and ATP per cell were used to measure physiological activity. Cell densities decreased significantly over time at both sites for both S. faecalis and E. coli; however, no significant differences in survival pattern were observed between S. faecalis and E.coli. Differences in protein synthesis between the two were only observed at a study site which was not heavily oiled. Although fecal streptococci have been suggested as a better indicator of fecal contamination than fecal coliforms in marine waters, in this study both E. coli and S. faecalis survived and remained physiologically active for extended periods of time. These results suggest that the fecal streptococci group is not a better indicator of fecal contamination in tropical marine waters than the fecal coliform group, especially when that environment is high in long-chained hydrocarbons.

Santo Domingo, J.W.; Fuentes, F.A.; Hazen, T.C. [Univ. of Puerto Rico, Rio Piedras (Puerto Rico). Microbial Ecology Lab.

1987-12-31T23:59:59.000Z

337

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

E-Print Network [OSTI]

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

Leal, Manuel S.

338

Sensitivity of Tropical Cyclone Intensity to Ventilation in an Axisymmetric Model  

E-Print Network [OSTI]

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 ...

Tang, Brian

339

Tropical climate variability from the last glacial maximum to the present  

E-Print Network [OSTI]

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 ...

Dahl, Kristina Ariel

2005-01-01T23:59:59.000Z

340

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

E-Print Network [OSTI]

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

Takahashi, Kozo

1982-01-01T23:59:59.000Z

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


341

GCM simulation of the tropical mixing barriers in the lower stratosphere  

E-Print Network [OSTI]

of the tropical easterly zonal flow and subtropical wave spectra. Wave spectrum analysis indicates that during the solstitial seasons there exists a zone in the tropics, which exactly matches the weak mixing zone, where there is relatively absence of westward...

Hu, Yongyun

1996-01-01T23:59:59.000Z

342

The rainfall over tropical South America generated by multiple scale processes.  

E-Print Network [OSTI]

??The rainfall regime over Central America and tropical South America is the most important hydro-meteorological event in the tropics after the Asian-Australian monsoon system. Therefore,Ö (more)

Carrillo, Carlos Mauricio

2010-01-01T23:59:59.000Z

343

Climate regulation of humid tropical hydrology BHS 10th National Hydrology Symposium, Exeter, 2008  

E-Print Network [OSTI]

might influence tropical water resources. Introduction The humid tropics can be defined as the global, Bangladesh, and most of South-east Asia (Fosberg et al., 1961). Its climate contains distinctive dynamics

Chappell, Nick A

344

The Role of Mineralogy in Organic Matter Stabilization in Tropical Soils  

E-Print Network [OSTI]

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

Sparks, Donald L.

345

SRS reactor control rod cooling without normal forced convection cooling  

SciTech Connect (OSTI)

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

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

1993-01-01T23:59:59.000Z

346

Gradients of meteorological parameters in convective and nonconvective areas  

E-Print Network [OSTI]

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

McCown, Milton Samuel

1976-01-01T23:59:59.000Z

347

Generation of large-scale winds in horizontally anisotropic convection  

E-Print Network [OSTI]

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

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

2015-01-01T23:59:59.000Z

348

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]

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, ...

Van der Helm, Mark Johan, 1972-

1996-01-01T23:59:59.000Z

349

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

E-Print Network [OSTI]

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

Bermingham, Eldredge

350

Mon. Not. R. Astron. Soc. 365, 276286 (2006) doi:10.1111/j.1365-2966.2005.09710.x The radial distribution of magnetic helicity in the solar convective zone  

E-Print Network [OSTI]

distribution of magnetic helicity in the solar convective zone: observations and dynamo theory H. Zhang,1 D Observatories, Chinese Academy of Sciences, Beijing 100012, China 2Department of Physics, Moscow State on current helicity in solar active regions with solar dynamo models. In addition to our previous results

Moss, David

2006-01-01T23:59:59.000Z

351

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

E-Print Network [OSTI]

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

Aluffi, Paolo

352

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

E-Print Network [OSTI]

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

Aluffi, Paolo

353

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

354

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

E-Print Network [OSTI]

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

Jackson, Robert B.

355

Interhemispheric Teleconnections from Tropical Heat Sources in Intermediate and Simple Models  

E-Print Network [OSTI]

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

356

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

E-Print Network [OSTI]

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

Standiford, Richard B.

357

Interactions between the tropical ISO and midlatitude low-frequency flow  

E-Print Network [OSTI]

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

Li, Tim

358

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

E-Print Network [OSTI]

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

Li, Tim

359

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

E-Print Network [OSTI]

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

Li, Tim

360

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

E-Print Network [OSTI]

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

Wang, Chunzai

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


361

Validating Atmospheric Reanalysis Data Using Tropical Cyclones as Thermometers James P. Kossin  

E-Print Network [OSTI]

1 Validating Atmospheric Reanalysis Data Using Tropical Cyclones as Thermometers James P. Kossin tropical cyclones as thermometers. Bull. Amer. Meteor. Soc. doi:10.1175/BAMS-D-14-00180, in press. Capsule Tropical cyclones are used as traveling thermometers to globally sample upper-tropospheric temperatures

Kossin, James P.

362

The divergent wind component in data sparse tropical wind fields  

E-Print Network [OSTI]

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...

Snyder, Bruce Alan

1985-01-01T23:59:59.000Z

363

Diurnal Cycle of Convection at the ARM SGP Site: Role of Large-Scale Forcing, Surface Fluxes, and Convective Inhibition  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation Proposed Newcatalyst phasesDataTranslocationDiurnal Cycle of Convection at the ARM SGP Site:

364

ARM - Midlatitude Continental Convective Clouds (jensen-sonde)  

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

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.

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

365

ARM - Midlatitude Continental Convective Clouds (jensen-sonde)  

SciTech Connect (OSTI)

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.

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

2012-01-19T23:59:59.000Z

366

Heat transport measurements in turbulent rotating Rayleigh-Benard convection  

SciTech Connect (OSTI)

We present experimental heat transport measurements of turbulent Rayleigh-Benard convection with rotation about a vertical axis. The fluid, water with Prandtl number ({sigma}) about 6, was confined in a cell which had a square cross section of 7.3 cm x 7.3 cm and a height of 9.4 cm. Heat transport was measured for Rayleigh numbers 2 x 10{sup 5} < Ra < 5 x 10{sup 8} and Taylor numbers 0 < Ta < 5 x 10{sup 9}. We show the variation of normalized heat transport, the Nusselt number, at fixed dimensional rotation rate {Omega}{sub D}, at fixed Ra varying Ta, at fixed Ta varying Ra, and at fixed Rossby number Ro. The scaling of heat transport in the range 10{sup 7} to about 10{sup 9} is roughly 0.29 with a Ro dependent coefficient or equivalently is also well fit by a combination of power laws of the form a Ra{sup 1/5} + b Ra{sup 1/3} . The range of Ra is not sufficient to differentiate single power law or combined power law scaling. The overall impact of rotation on heat transport in turbulent convection is assessed.

Ecke, Robert E [Los Alamos National Laboratory; Liu, Yuanming [Los Alamos National Laboratory

2008-01-01T23:59:59.000Z

367

Kinetics of the clay roofing tile convection drying  

SciTech Connect (OSTI)

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

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

1993-01-01T23:59:59.000Z

368

A Multiscale Dynamo Model Driven by Quasi-geostrophic Convection  

E-Print Network [OSTI]

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

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

2015-01-01T23:59:59.000Z

369

Particle filter based on thermophoretic deposition from natural convection flow  

SciTech Connect (OSTI)

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

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

1994-04-01T23:59:59.000Z

370

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

371

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

E-Print Network [OSTI]

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

372

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

E-Print Network [OSTI]

≠10]. Among the finite enclosures, free convective heat transfer in a differentially heated vertical porous in a vertical annular enclosure for a wide range of radius and aspect ratios, and also used an approximateNumerical study of natural convection in a vertical porous annulus with discrete heating M. Sankar

Lopez, John M.

373

Numerical Investigation of Natural Convection Loss in Cavity-Type Solar Receivers  

E-Print Network [OSTI]

Work There have been several previous investigations of natural convection heat loss from open the convective heat loss, i.e., (i) the ability to transfer mass and energy across the aperture and (ii to investigate three cases of geometrically different receivers. The calculated heat loss results shows

374

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

E-Print Network [OSTI]

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

Paris-Sud XI, Universitť de

375

The impact of methane thermodynamics on seasonal convection and circulation in a model Titan atmosphere  

E-Print Network [OSTI]

The impact of methane thermodynamics on seasonal convection and circulation in a model Titan mechanisms controlling the distribution of methane convection and large-scale circulation in a simplified, axisymmetric model atmosphere of Titan forced by gray radiation and moist (methane) con- vection. The large

Caballero, Rodrigo

376

Pattern formation in binary mixture convection in cylindrical three-dimensional cells  

E-Print Network [OSTI]

present numerical results of pattern selection near the onset of convection for a water-ethanol mixture of the cell is = 11. The onset of convection occurs via a subcritical Hopf bifurcation. Slightly above ratio mixtures, S subcritical and gives rise

Batiste, Oriol

377

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

E-Print Network [OSTI]

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

Abbett, Bill

378

ARM - Midlatitude Continental Convective Clouds - Ultra High Sensitivity Aerosol Spectrometer(tomlinson-uhsas)  

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

Ultra High Sensitivity Aerosol Spectrometer (UHSASA) 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. These files contain brightness temperatures observed at Purcell during MC3E. The measurements were made with a 5 channel (22.235, 23.035, 23.835, 26.235, 30.000GHz) microwave radiometer at one minute intervals. The results have been separated into daily files and the day of observations is indicated in the file name. All observations were zenith pointing. Included in the files are the time variables base_time and time_offset. These follow the ARM time conventions. Base_time is the number seconds since January 1, 1970 at 00:00:00 for the first data point of the file and time_offset is the offset in seconds from base_time.

Tomlinson, Jason; Jensen, Mike

379

ARM - Midlatitude Continental Convective Clouds Microwave Radiometer Profiler (jensen-mwr)  

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

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. These files contain brightness temperatures observed at Purcell during MC3E. The measurements were made with a 5 channel (22.235, 23.035, 23.835, 26.235, 30.000GHz) microwave radiometer at one minute intervals. The results have been separated into daily files and the day of observations is indicated in the file name. All observations were zenith pointing. Included in the files are the time variables base_time and time_offset. These follow the ARM time conventions. Base_time is the number seconds since January 1, 1970 at 00:00:00 for the first data point of the file and time_offset is the offset in seconds from base_time.

Jensen, Mike

380

ARM - Midlatitude Continental Convective Clouds Microwave Radiometer Profiler (jensen-mwr)  

SciTech Connect (OSTI)

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. These files contain brightness temperatures observed at Purcell during MC3E. The measurements were made with a 5 channel (22.235, 23.035, 23.835, 26.235, 30.000GHz) microwave radiometer at one minute intervals. The results have been separated into daily files and the day of observations is indicated in the file name. All observations were zenith pointing. Included in the files are the time variables base_time and time_offset. These follow the ARM time conventions. Base_time is the number seconds since January 1, 1970 at 00:00:00 for the first data point of the file and time_offset is the offset in seconds from base_time.

Jensen, Mike

2012-02-01T23:59:59.000Z

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


381

ARM - Midlatitude Continental Convective Clouds - Ultra High Sensitivity Aerosol Spectrometer(tomlinson-uhsas)  

SciTech Connect (OSTI)

Ultra High Sensitivity Aerosol Spectrometer (UHSASA) 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. These files contain brightness temperatures observed at Purcell during MC3E. The measurements were made with a 5 channel (22.235, 23.035, 23.835, 26.235, 30.000GHz) microwave radiometer at one minute intervals. The results have been separated into daily files and the day of observations is indicated in the file name. All observations were zenith pointing. Included in the files are the time variables base_time and time_offset. These follow the ARM time conventions. Base_time is the number seconds since January 1, 1970 at 00:00:00 for the first data point of the file and time_offset is the offset in seconds from base_time.

Tomlinson, Jason; Jensen, Mike

2012-02-28T23:59:59.000Z

382

EXPERIMENTAL INVESTIGATION OF NATURAL CONVECTION HEAT TRANSFER OF IONIC LIQUID IN A RECTANGULAR ENCLOSURE HEATED FROM BELOW  

SciTech Connect (OSTI)

This paper presents an experimental study of natural convection heat transfer for an Ionic Liquid. The experiments were performed for 1-butyl-2, 3-dimethylimidazolium bis(trifluoromethylsulfonyl)imide, ([C{sub 4}mmim][NTf{sub 2}]) at a Raleigh number range of 1.26 x 10{sup 7} to 8.3 x 10{sup 7}. In addition to determining the convective heat transfer coefficients, this study also included experimental determination of thermophysical properties of [C{sub 4}mmim][NTf{sub 2}] such as, density, viscosity, heat capacity, and thermal conductivity. The results show that the density of [C{sub 4}mmim][NTf{sub 2}] varies from 1.437-1.396 g/cm{sup 3} within the temperature range of 10-50 C, the thermal conductivity varies from 0.105-0.116 W/m.K between a temperature of 10 to 60 C, the heat capacity varies from 1.015 J/g.K - 1.760 J/g.K within temperature range of 25-340 C and the viscosity varies from 18cp-243cp within temperature range 10-75 C. The results for density, thermal conductivity, heat capacity, and viscosity were in close agreement with the values in the literature. Measured dimensionless Nusselt number was observed to be higher for the ionic liquid than that of DI water. This is expected as Nusselt number is the ratio of heat transfer by convection to conduction and the ionic liquid has lower thermal conductivity (approximately 18%) than DI water.

Fox, E.; Visser, A.; Bridges, N.

2011-07-18T23:59:59.000Z

383

GFDL ARM Project Technical Report: Using ARM Observations to Evaluate Cloud and Convection Parameterizations & Cloud-Convection-Radiation Interactions in the GFDL Atmospheric General Circulation Model  

SciTech Connect (OSTI)

This report briefly summarizes the progress made by ARM postdoctoral fellow, Yanluan Lin, at GFDL during the period from October 2008 to present. Several ARM datasets have been used for GFDL model evaluation, understanding, and improvement. This includes a new ice fall speed parameterization with riming impact and its test in GFDL AM3, evaluation of model cloud and radiation diurnal and seasonal variation using ARM CMBE data, model ice water content evaluation using ARM cirrus data, and coordination of the TWPICE global model intercomparison. The work illustrates the potential and importance of ARM data for GCM evaluation, understanding, and ultimately, improvement of GCM cloud and radiation parameterizations. Future work includes evaluation and improvement of the new dynamicsPDF cloud scheme and aerosol activation in the GFDL model.

V. Ramaswamy; L. J. Donner; J-C. Golaz; S. A. Klein

2010-06-17T23:59:59.000Z

384

NUMERICAL DETERMINATION AND TREATMENT OF CONVECTIVE HEAT TRANSFER COEFFICIENT IN THE COUPLED BUILDING ENERGY AND CFD SIMULATION  

E-Print Network [OSTI]

for the correct prediction of the convective heat. A finer grid resolution in CFD does not always lead to a more conservation equations of flow on these grid cells. As shown in Figure 1(a), CFD calculates convective heat1 NUMERICAL DETERMINATION AND TREATMENT OF CONVECTIVE HEAT TRANSFER COEFFICIENT IN THE COUPLED

Chen, Qingyan "Yan"

385

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

E-Print Network [OSTI]

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

Michigan, University of

386

Orogenic Convection in Subtropical South America as Seen by the TRMM Satellite KRISTEN L. RASMUSSEN AND ROBERT A. HOUZE JR.  

E-Print Network [OSTI]

Orogenic Convection in Subtropical South America as Seen by the TRMM Satellite KRISTEN L. RASMUSSEN storms in southeastern South America are divided into three categories: storms with deep convective cores, the intense storms with wide convective cores over southeastern South America are unlike their Himalayan

Houze Jr., Robert A.

387

TROPICAL MULTIPLICATION MAPS AND THE GIESEKER-PETRI THEOREM  

E-Print Network [OSTI]

TROPICAL MULTIPLICATION MAPS AND THE GIESEKER-PETRI THEOREM DAVID JENSEN AND SAM PAYNE Abstract. We. Supported in part by NSF grants DMS≠1068689 and CAREER DMS≠1149054. 1 #12;2 DAVID JENSEN AND SAM PAYNE v1 w1 by the addition or deletion of a bridge are canonically isomorphic, and these isomorphisms respect the images of the

Payne, Sam

388

Fungal endophytes limit pathogen damage in a tropical tree  

E-Print Network [OSTI]

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

Bermingham, Eldredge

389

Global Patterns of Ecological Productivity and Tropical Forest Biomass  

E-Print Network [OSTI]

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

Wisconsin at Madison, University of

390

A QuikSCAT climatology of tropical cyclone size  

E-Print Network [OSTI]

QuikSCAT data of near-surface wind vectors for the years 1999Ė2008 are used to create a climatology of tropical cyclone (TC) size, defined as the radius of vanishing winds. The azimuthally-averaged radius of 12 ms?1 [ms ...

Chavas, Daniel Robert

391

Low beta diversity of herbivorous insects in tropical forests  

E-Print Network [OSTI]

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

Basset, Yves

392

Variable Responses of Lowland Tropical Forest Nutrient Status  

E-Print Network [OSTI]

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

Harms, Kyle E.

393

Association for Tropical Biology and Conservation Brownsberg Declaration 2008  

E-Print Network [OSTI]

Paramaribo, Suriname VERKLARING INZAKE HET TOEKENNEN VAN PERMANENT BESCHERMDE STATUS AAN DE BROWNSBERG EN DE. IN OVERWEGING NEMENDE DAT de bauxiethoudende Bergen in noordoost- Suriname ­ Brownsberg, Nassau en Lely ­ deelAssociation for Tropical Biology and Conservation Brownsberg Declaration 2008 13 June 2008

Norconk, Marilyn A.

394

TROPIC: Transactional Resource Orchestration Platform In the Cloud  

E-Print Network [OSTI]

TROPIC: Transactional Resource Orchestration Platform In the Cloud Changbin Liu, Yun Mao*, Xu Chen ­ InfrastructureasaService (IaaS) Cloud · Provide cloud infrastructure services: virtual machines (VMs), virtual block devices, VPNs · Widely adopted, e.g. Amazon Elastic Compute Cloud (EC2) ­ Cloud resource

Plotkin, Joshua B.

395

Temporal Changes in a Tropical Nekton Assemblage and  

E-Print Network [OSTI]

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

396

Detection of iodine monoxide in the tropical free troposphere  

E-Print Network [OSTI]

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

397

Arbuscular mycorrhizal mycelial respiration in a moist tropical forest  

E-Print Network [OSTI]

Universiteit, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands; 4 Ecological Farming Systems, Research Tropical Research Institute, 0843- 03092 Balboa, Ancon, Panama; 3 Institute of Ecological Science, Vrije Station ART, Swiss Federal Research Institute Agroscope, Zurich, Switzerland; 5 Plant­Microbe Interactions

Bermingham, Eldredge

398

Environmental Factors Affecting Tropical Cyclone Power Dissipation KERRY EMANUEL  

E-Print Network [OSTI]

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

Emanuel, Kerry A.

399

Tropical methane emissions: A revised view from SCIAMACHY onboard ENVISAT  

E-Print Network [OSTI]

Tropical methane emissions: A revised view from SCIAMACHY onboard ENVISAT Christian Frankenberg,1; accepted 26 June 2008; published 12 August 2008. [1] Methane retrievals from near-infrared spectra recorded spectroscopic parameters, causing a substantial overestimation of methane correlated with high water vapor

Haak, Hein

400

Sources of atmospheric mercury in the tropics: continuous observations at a coastal site in Suriname  

E-Print Network [OSTI]

to mercury pollution in SurinameĒ including oxidation byat a coastal site in Suriname 1 , D. Wip 2 , T. Warneke 1 ,de Kom Universiteit van Suriname, Paramaribo, Suriname 3

Muller, D.; Wip, D.; Warneke, T.; Holmes, C. D; Dastoor, A.; Notholt, J.

2012-01-01T23:59:59.000Z

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


401

Tropical synoptic scale moisture fields observed from the Nimbus-7 SMMR  

E-Print Network [OSTI]

are clear and the radiating surface is near sea level and warm. Correlation in the low (less than 220 W m ) OLR (wet) regions of the TP and AITCZ have a large scatter and the highest precipitable water values do not correspond to the lowest OLR values... there is little relation between the variations of moisture and the absence of cloud. The lowest (wet) values of OLR, mostly from the TP and AITCZ, occupy s, 15 kg m range (excluding many SMMR values erroneously low) of SMMR precipitable water estimates. Cadet...

Fink, Jeffrey David

1989-01-01T23:59:59.000Z

402

A census of precipitation features in the tropics using TRMM: radar, ice scattering, and lightning observations  

E-Print Network [OSTI]

and two ocean regions during August, September and October 1998, this study used radar retrievals and 85 GHz Polarization Corrected Temperatures (PCTs, which passively measure relative concentrations of precipitation-sized ice particles within a cloud...

Nesbitt, Stephen William

1999-01-01T23:59:59.000Z

403

Remote Sensing Observations from MTI Satellites and GMS Over Tropical Island of Nauru  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 -the Mid-Infrared at 278, 298,NIST31 ORV 15051 ModificationRemote AccessJ.E.M.Remote

404

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

E-Print Network [OSTI]

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

Rutledge, Steven

405

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

E-Print Network [OSTI]

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

Sherwood, Steven

406

Regional Contrast of Mesoscale Convective System Structure prior to and during Monsoon Onset across South America  

E-Print Network [OSTI]

South America THOMAS M. RICKENBACH, ROSANA NIETO-FERREIRA, AND RICHARD P. BARNHILL* Department across tropical and subtropical South America. The approach is to contrast regional differences tropical South America has the characteristic summertime maximum of a monsoon climate (Kousky 1988; Horel

Nesbitt, Steve

407

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

SciTech Connect (OSTI)

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

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

2014-11-27T23:59:59.000Z

408

Structure of the tropical lower stratosphere as revealed by three reanalysis data sets  

SciTech Connect (OSTI)

While the skill of climate simulation models has advanced over the last decade, mainly through improvements in modeling, further progress will depend on the availability and the quality of comprehensive validation data sets covering long time periods. A new source of such validation data is atmospheric {open_quotes}reanalysis{close_quotes} where a fixed, state-of-the-art global atmospheric model/data assimilation system is run through archived and recovered observations to produce a consistent set of atmospheric analyses. Although reanalysis will be free of non-physical variability caused by changes in the models and/or the assimilation procedure, it is necessary to assess its quality. A region for stringent testing of the quality of reanalysis is the tropical lower stratosphere. This portion of the atmosphere is sparse in observations but displays the prominent quasi-biennial oscillation (QBO) and an annual cycle, neither of which is fully understood, but which are likely coupled dynamically. We first consider the performance of three reanalyses, from NCEP/NCAR, NASA and ECMWF, against rawinsonde data in depicting the QBO and then examine the structure of the tropical lower stratosphere in NCEP and ECMWF data sets in detail. While the annual cycle and the QBO in wind and temperature are quite successfully represented, the mean meridional circulations in NCEP and ECMWF data sets contain unusual features which may be due to the assimilation process rather than being physically based. Further, the models capture the long-term temperature fluctuations associated with volcanic eruptions, even though the physical mechanisms are not included, thus implying that the model does not mask prominent stratospheric signals in the observational data. We conclude that reanalysis offers a unique opportunity to better understand the dynamics of QBO and can be applied to climate model validation.

Pawson, S. [Free Univ. of Berlin (Germany). Institute for Meteorology; Fiorino, M. [Lawrence Livermore National Lab., CA (United States)

1996-05-01T23:59:59.000Z

409

Wind reversals in turbulent Rayleigh-Benard convection  

E-Print Network [OSTI]

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 / (\

Francisco Fontenele Araujo; S. Grossmann; D. Lohse

2005-08-29T23:59:59.000Z

410

Apparatus for production of synthesis gas using convective reforming  

SciTech Connect (OSTI)

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

Karafian, M.; Tsang, I.C.

1991-04-09T23:59:59.000Z

411

The structure and dynamics of patterns of Benard convection cells  

SciTech Connect (OSTI)

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.

Rivier, N. (Argonne National Lab., IL (USA) Imperial Coll. of Science and Technology, London (UK). Blackett Lab. Lausanne Univ. (Switzerland). Inst. de Physique Experimentale)

1990-08-01T23:59:59.000Z

412

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

SciTech Connect (OSTI)

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

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

2013-05-20T23:59:59.000Z

413

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

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

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.

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

2014-10-27T23:59:59.000Z

414

QUANTITATIVE ECOLOGY Airborne Radar Observations of the Flight Behavior of Small Insects in  

E-Print Network [OSTI]

, with the vertical air velocity measured at √?ight level. We hypothesize that the gregarious behavior of small insectsQUANTITATIVE ECOLOGY Airborne Radar Observations of the Flight Behavior of Small Insects of insects in the convective boundary layer (CBL) is examined by means of pro√?ling airborne Doppler radar

Geerts, Bart

415

LIDAR OBSERVATIONS AND COMPARISON WITH NUMERICAL SIMULATION OF A LAKE MICHIGAN LAND BREEZE FRONT  

E-Print Network [OSTI]

of the Lake-Induced Convection Experiments (Lake-ICE), on December 21, 1997 the University of Wisconsin VolumeLIDAR OBSERVATIONS AND COMPARISON WITH NUMERICAL SIMULATION OF A LAKE MICHIGAN LAND BREEZE FRONT G circulation over Lake Michigan. Backscatter returns revealed a steady offshore flow extending 1.5 to 4 km

Eloranta, Edwin W.

416

Meteorological significance of frontal thin-line angel echoes observed by CPS-9 radar  

E-Print Network [OSTI]

Effects of Vertical Wind-Shear on Convection Cells in the Atmosphere and Ocean 83 86 C. Radar Observations of Benard Cells and the Effects of Vertical Wind-Shear 89 D. Possible Effects of Wind-Shear Modified Convection Cells Exhibited by the Angel... of the Relationship between Wind-shear and Angel Echo Patterns 102 D. Summary of Conclusions REFERENCES APPENDIX 103 105 110 LIST OF FIGURES Figure 1. Surface Nap, 1500C, 10 December 1957 2. PPI Photographs~ 10 December 1957 3. Cold-frontal and Thin...

Miller, Donald Bradford

2012-06-07T23:59:59.000Z

417

Corrosion of type 316L stainless steel in a mercury thermal convection loop  

SciTech Connect (OSTI)

Two thermal convection loops fabricated from 316L stainless steel containing mercury (Hg) and Hg with 1000 wppm gallium (Ga), respectively, were operated continuously for about 5000 h. In each case, the maximum loop temperature was constant at about 305 degrees C and the minimum temperature was constant at about 242 degrees C. Coupons in the hot leg of the Hg-loop developed a posous surface layer substantially depleted of nickel and chromium, which resulted in a transformation to ferrite. The coupon exposed at the top of the hot leg in the Hg-loop experienced the maximum degradation, exhibiting a surface layer extending an average of 9-10 mu m after almost 5000 h. Analysis of the corrosion rate data as a function of temperature (position) in the Hg-loop suggests wetting by the mer cury occurred only above about 255 degrees C and that the rate limiting step in the corrosion process above 255 degrees C is solute diffusion through the saturated liquid boundary layer adjacent to the corroding surface. The latter factor suggests that the corrosion of 316L stainless steel in a mercury loop may be velocity dependent. No wetting and no corrosion were observed on the coupons and wall specimens removed from the Hg/Ga loop after 5000 h of operation.

DiStefano, J.R.; Manneschmidt, E.T.; Pawel, S.J.

1999-04-01T23:59:59.000Z

418

Physica D 143 (2000) 169186 Surface tension-driven convection patterns in two liquid layers  

E-Print Network [OSTI]

Physica D 143 (2000) 169­186 Surface tension-driven convection patterns in two liquid layers Anne a liquid layer with a free surface is heated from below, both surface tension gradients and buoyancy may

Texas at Austin. University of

419

A visualization comparison of convective flow boiling heat transfer augmentation devices  

E-Print Network [OSTI]

The qualitative effects of inset-table heat transfer phics. augmentation devices on vertical in-tube convective flow boiling flow regimes, transition mechanisms, and heat transfer are presented in this study. Three twisted tapes with twist ratios...

Lundy, Brian Franklin

1998-01-01T23:59:59.000Z

420

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

E-Print Network [OSTI]

radiation-convection feedbacks are usually invoked to explain the open oceanocean] diurnal [rainfall] cycle can be qualita- tively accounted for by direct radiation-ocean is often maximized in the early morning hours, colloquially called the ďDynamic-Radiation-

Pritchard, Michael Stephen

2011-01-01T23:59:59.000Z

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


421

Numerical analysis of binary solid-liquid phase change with buoyancy and surface tension driven convection  

SciTech Connect (OSTI)

The effects of thermo/diffusocapillary convection on the solidification of aqueous NH{sub 4}Cl in a rectangular cavity have been simulated numerically using a newly developed continuum model. Diffusocapillary convection is negligible relative to thermocapillary convection, and for a 20 {times} 20 mm cavity in a one-gravity environment, thermocapillary effects are most pronounced during the early stages of solidification, when flow conditions are characterized by three major cells. One cell, driven by solutal buoyancy forces, extends from the mush region to the melt and separates top and bottom melt region cells driven primarily by surface tension and buoyancy forces, respectively. With increasing time, however, the top cell strengthens and eventually envelops the entire melt. In terms of the strength of the flow, the liquidus front morphology, and the amount of solid formed, final conditions differ only slightly from those predicted for pure thermal/solutal convection.

Incropera, F.P.; Engel, A.H.H. (Purdue Univ., Lafayette, IN (USA). Heat Transfer Lab.); Bennon, W.D. (Alcoa Technical Center, Alcoa Center, PA (US))

1989-01-01T23:59:59.000Z

422

Rheology and Convective Heat Transfer of Colloidal Gas Aphrons in Horizontal Minichannels  

E-Print Network [OSTI]

Single-phase convective heat transfer in microchannels: aand Newell, M. E. , 1967. Heat transfer in fully developed3 /s at 130 W. Water CGA Heat Transfer Coefficient, h (W/m 2

Tseng, H.; Pilon, L.; Warrier, G.

2006-01-01T23:59:59.000Z

423

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

E-Print Network [OSTI]

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 ...

Prabhat, Naveen

424

Thermal perturbations caused by large impacts and consequences for mantle convection  

E-Print Network [OSTI]

We examine the effects of thermal perturbations on a convecting layer of incompressible fluid with uniform viscosity in the limit of infinite Prandtl number, for two upper boundary conditions (free- and no-slip) and heat ...

Watters, W. A.

425

Dusty gust fronts and their contributions to long-lived convection in West Africa/  

E-Print Network [OSTI]

To model and predict the behavior of West African storms and mesoscale convective systems (MCSs), we must understand the life cycle of gust fronts, which invariably accompany thunderstorms and often initiate them. In this ...

McGraw-Herdeg, Michael (Michael P.)

2010-01-01T23:59:59.000Z

426

Study of formation and convective transport of aerosols using optical diagnostic technique  

E-Print Network [OSTI]

. Part II investigates the characteristics of convective transport behavior of solid particles in virtual impactor (VI). The objective of part I is to establish correlations which offer predictions on atomized particle size of HTFs which are widely...

Kim, Tae-Kyun

2004-09-30T23:59:59.000Z

427

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

E-Print Network [OSTI]

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 ...

Gianotti, Rebecca L. (Rebecca Louise)

2013-01-01T23:59:59.000Z

428

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

E-Print Network [OSTI]

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, ...

Kaspi, Yohai

2008-01-01T23:59:59.000Z

429

Urban Aerosol Impacts on Downwind Convective Storms SUSAN C. VAN DEN HEEVER AND WILLIAM R. COTTON  

E-Print Network [OSTI]

Urban Aerosol Impacts on Downwind Convective Storms SUSAN C. VAN DEN HEEVER AND WILLIAM R. COTTON. 2004; Givati and Rosenfeld 2004; Molders and Olson 2004; Jirak and Cotton 2006); 2) increased surface

Collett Jr., Jeffrey L.

430

STUDY OF MHD MIXED CONVECTION IN THE DCLL BLANKET SMOLENTSEV Sergey1  

E-Print Network [OSTI]

, and ABDOU Mohamed3 1 University of California, Los Angeles, USA, sergey@fusion.ucla.edu 2 Laboratoire SIMAP, abdou@fusion.ucla.edu Abstract: Magnetohydrodynamic mixed convection associated with a non

Abdou, Mohamed

431

Climate mitigation and the future of tropical landscapes  

SciTech Connect (OSTI)

Land use change to meet 21st Century demands for food, fuel, and fiber will occur in the context of both a changing climate as well as societal efforts to mitigate climate change. This changing natural and human environment will have large consequences for forest resources, terrestrial carbon storage and emissions, and food and energy crop production over the next century. Any climate change mitigation policies enacted will change the environment under which land-use decisions are made and alter global land use change patterns. Here we use the GCAM integrated assessment model to explore how climate mitigation policies that achieve a climate stabilization at 4.5 W m-2 radiative forcing in 2100 and value carbon in terrestrial ecosystems interact with future agricultural productivity and food and energy demands to influence land use in the tropics. The regional land use results are downscaled from GCAM regions to produce gridded maps of tropical land use change. We find that tropical forests are preserved only in cases where a climate mitigation policy that values terrestrial carbon is in place, and crop productivity growth continues throughout the century. Crop productivity growth is also necessary to avoid large scale deforestation globally and enable the production of bioenergy crops. The terrestrial carbon pricing assumptions in GCAM are effective at avoiding deforestation even when cropland must expand to meet future food demand.

Thomson, Allison M.; Calvin, Katherine V.; Chini, Louise Parsons; Hurtt, George; Edmonds, James A.; Bond-Lamberty, Benjamin; Frolking, Steve; Wise, Marshall A.; Janetos, Anthony C.

2010-11-16T23:59:59.000Z

432

A study of the relationship between certain moisture parameters and severe convective storms in central Oklahoma  

E-Print Network [OSTI]

A STUDY OF THE RELATIONSHIP BETWEEN CERTAIN MOISTURE PARAMETERS AND SEVERE CONVECTIVE STORMS IN CENTRAL OKLAHOMA A Thesis by CARVEN ALLEN SCOTT Submitted to the Graduate College of Texas ASM University in partial fulfillment... of the requirement for the degree of MASTER OF SCIENCE May 1977 Major Subject: Meteorology A STUDY OF THE RELATIONSHIP BETWEEN CERTAIN MOISTURE PARAMETERS AND SEVERE CONVECTIVE STORMS IN CENTRAL OKLAHOMA A Thesis by CARVEN ALLEN SCOTT Approved as to style...

Scott, Carven Allen

2012-06-07T23:59:59.000Z

433

P 3.2 OBJECTIVE ENVIRONMENTAL ANALYSES AND CONVECTIVE MODES FOR U.S. TROPICAL CYCLONE TORNADOES FROM 2003-2008  

E-Print Network [OSTI]

FROM 2003-2008 Roger Edwards 1 , Andrew R. Dean, Richard L. Thompson and Bryan T. Smith Storm Prediction Center, Norman, OK 1 Corresponding author address: Roger Edwards, Storm Prediction Center, National Weather Center, 120 Boren Blvd #2300, Norman, OK 73072; E-mail: roger.edwards@noaa.gov 1

434

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

E-Print Network [OSTI]

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

Stephens, Graeme L.

435

Understanding and Improving CRM and GCM Simulations of Cloud Systems with ARM Observations  

SciTech Connect (OSTI)

The works supported by this ASR project lay the solid foundation for improving the parameterization of convection and clouds in the NCAR CCSM and the climate simulations. We have made a significant use of CRM simulations and ARM observations to produce thermodynamically and dynamically consistent multi-year cloud and radiative properties; improve the GCM simulations of convection, clouds and radiative heating rate and fluxes using the ARM observations and CRM simulations; and understand the seasonal and annual variation of cloud systems and their impacts on climate mean state and variability. We conducted multi-year simulations over the ARM SGP site using the CRM with multi-year ARM forcing data. The statistics of cloud and radiative properties from the long-term CRM simulations were compared and validated with the ARM measurements and value added products (VAP). We evaluated the multi-year climate simulations produced by the GCM with the modified convection scheme. We used multi-year ARM observations and CRM simulations to validate and further improve the trigger condition and revised closure assumption in NCAR GCM simulations that demonstrate the improvement of climate mean state and variability. We combined the improved convection scheme with the mosaic treatment of subgrid cloud distributions in the radiation scheme of the GCM. The mosaic treatment of cloud distributions has been implemented in the GCM with the original convection scheme and enables the use of more realistic cloud amounts as well as cloud water contents in producing net radiative fluxes closer to observations. A physics-based latent heat (LH) retrieval algorithm was developed by parameterizing the physical linkages of observed hydrometeor profiles of cloud and precipitation to the major processes related to the phase change of atmospheric water.

Wu, Xiaoqing

2014-02-25T23:59:59.000Z

436

Effects of Radiative Diffusion on Thin Flux Tubes in Turbulent Solar-like Convection  

E-Print Network [OSTI]

We study the combined effects of convection and radiative diffusion on the evolution of thin magnetic flux tubes in the solar interior. Radiative diffusion is the primary supplier of heat to convective motions in the lower convection zone, and it results in a heat input per unit volume of magnetic flux tubes that has been ignored by many previous thin flux tube studies. We use a thin flux tube model subject to convection taken from a rotating spherical shell of turbulent, solar-like convection as described by Weber, Fan, and Miesch (2011, Astrophys. J., 741, 11; 2013, Solar Phys., 287, 239), now taking into account the influence of radiative heating on flux tubes of large-scale active regions. Our simulations show that flux tubes of less than or equal to 60 kG subject to solar-like convective flows do not anchor in the overshoot region, but rather drift upward due to the increased buoyancy of the flux tube earlier in its evolution as a result of the inclusion of radiative diffusion. Flux tubes of magnetic fie...

Weber, Maria A

2015-01-01T23:59:59.000Z

437

Universidade de Braslia Faculdade de Medicina Programa de Ps-Graduao em Medicina Tropical  

E-Print Network [OSTI]

Universidade de Bras√≠lia ¬≠ Faculdade de Medicina Programa de P√≥s-Gradua√ß√£o em Medicina Tropical Edital n o . 1/2012 1 PROGRAMA DE P√?S-GRADUA√?√?O EM MEDICINA TROPICAL EDITAL No. 01/2012 SELE√?√?O DE CANDIDATOS √?S VAGAS DO PROGRAMA DE P√?S-GRADUA√?√?O EM MEDICINA TROPICAL PARA OS CURSOS DE MESTRADO ACAD√?MICO E

Maier, Rudolf Richard

438

UNIVERSIDADE DE BRASLIA PROGRAMA DE PS-GRADUAO EM MEDICINA TROPICAL  

E-Print Network [OSTI]

UNIVERSIDADE DE BRAS√ćLIA PROGRAMA DE P√?S-GRADUA√?√?O EM MEDICINA TROPICAL EDITAL No. 02/2010 SELE√?√?O DE CANDIDATOS √?S VAGAS DO PROGRAMA DE P√?S-GRADUA√?√?O EM MEDICINA TROPICAL PARA OS CURSOS DE MESTRADO P√≥s-Gradua√ß√£o em Medicina Tropical, no uso de suas atribui√ß√Ķes legais, torna p√ļblico e estabelece

Maier, Rudolf Richard

439

UNIVERSIDADE DE BRASLIA PROGRAMA DE PS-GRADUAO EM MEDICINA TROPICAL  

E-Print Network [OSTI]

UNIVERSIDADE DE BRAS√ćLIA PROGRAMA DE P√?S-GRADUA√?√?O EM MEDICINA TROPICAL EDITAL No. 01/2009 SELE√?√?O DE CANDIDATOS √?S VAGAS DO PROGRAMA DE P√?S-GRADUA√?√?O EM MEDICINA TROPICAL PARA OS CURSOS DE MESTRADO INFECCIOSAS E PARASIT√ĀRIAS 1. PRE√?MBULO 1.1 O Coordenador do Programa de P√≥s-Gradua√ß√£o em Medicina Tropical

Maier, Rudolf Richard

440

UNIVERSIDADE DE BRASLIA PROGRAMA DE PS-GRADUAO EM MEDICINA TROPICAL  

E-Print Network [OSTI]

UNIVERSIDADE DE BRAS√ćLIA PROGRAMA DE P√?S-GRADUA√?√?O EM MEDICINA TROPICAL EDITAL No. 03/2011 SELE√?√?O DE CANDIDATOS √?S VAGAS DO PROGRAMA DE P√?S-GRADUA√?√?O EM MEDICINA TROPICAL PARA OS CURSOS DE MESTRADO Gradua√ß√£o em Medicina Tropical, no uso de suas atribui√ß√Ķes legais, torna p√ļblico e estabelece a retifica√ß√£o

Lucero, Jorge Carlos

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


441

UNIVERSIDADE DE BRASLIA PROGRAMA DE PS-GRADUAO EM MEDICINA TROPICAL  

E-Print Network [OSTI]

1 UNIVERSIDADE DE BRAS√ćLIA PROGRAMA DE P√?S-GRADUA√?√?O EM MEDICINA TROPICAL EDITAL No. 02/2011 SELE√?√?O DE CANDIDATOS √?S VAGAS DO PROGRAMA DE P√?S-GRADUA√?√?O EM MEDICINA TROPICAL PARA OS CURSOS DE de P√≥s Gradua√ß√£o em Medicina Tropical, no uso de suas atribui√ß√Ķes legais, torna p√ļblico e estabelece

Lucero, Jorge Carlos

442

OBSERVATIONS ON DISTRIBUTION AND LIFE HISTORY OF SKIPJACK TUNA, KATSUWONUS PELAMIS, IN  

E-Print Network [OSTI]

OBSERVATIONS ON DISTRIBUTION AND LIFE HISTORY OF SKIPJACK TUNA, KATSUWONUS PELAMIS, IN AUSTRALIAN, Katsuwonus pelamis (Lin- naeus), occurs in tropical and warm temperate waters of all oceans. It supports, however, and both names are now used in Australia. Therefore we now refer to Katsuwonus pelamis

443

Longwave radiative forcing of Saharan dust aerosols estimated from MODIS, MISR, and CERES observations on Terra  

E-Print Network [OSTI]

observations from the Advanced Very High Resolution Radiometer (AVHRR) [Ackerman and Chung, 1992] and the Total's Radiant Energy System (CERES) instruments onboard the Terra satellite; we present a new technique prevalent in the tropics [Prospero, 1999], dust aerosols are effective in reflecting solar energy back

Christopher, Sundar A.

444

Dynamical and chemical characteristics of tropospheric intrusions observed during START08  

E-Print Network [OSTI]

. Homeyer,1 Kenneth P. Bowman,1 Laura L. Pan,2 Elliot L. Atlas,3 RuShan Gao,4 and Teresa L. Campos2 Received that the intruding air masses can be traced back to the tropical upper troposphere and lower stratosphere. In situ of the observed intrusions through use of a simple box model and trace species with different photochemical

Pan, Laura

445

Radial convection of finite ion temperature, high amplitude plasma blobs  

SciTech Connect (OSTI)

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.

Wiesenberger, M., E-mail: Matthias.Wiesenberger@uibk.ac.at; Kendl, A. [Institute for Ion Physics and Applied Physics, Association EURATOM-÷AW, University of Innsbruck, A-6020 Innsbruck (Austria); Madsen, J. [Association EURATOM-DTU, Department of Physics, Technical University of Denmark, 2800 Kgs. Lyngby (Denmark)

2014-09-15T23:59:59.000Z

446

Convective Heating of the LIFE Engine Target During Injection  

SciTech Connect (OSTI)

Target survival in the hostile, high temperature xenon environment of the proposed Laser Inertial Fusion Energy (LIFE) engine is critical. This work focuses on the flow properties and convective heat load imposed upon the surface of the indirect drive target while traveling through the xenon gas. While this rarefied flow is traditionally characterized as being within the continuum regime, it is approaching transition where conventional CFD codes reach their bounds of operation. Thus ANSYS, specifically the Navier-Stokes module CFX, will be used in parallel with direct simulation Monte Carlo code DS2V and analytically and empirically derived expressions for heat transfer to the hohlraum for validation. Comparison of the viscous and thermal boundary layers of ANSYS and DS2V were shown to be nearly identical, with the surface heat flux varying less than 8% on average. From the results herein, external baffles have been shown to reduce this heat transfer to the sensitive laser entrance hole (LEH) windows and optimize target survival independent of other reactor parameters.

Holdener, D S; Tillack, M S; Wang, X R

2011-10-24T23:59:59.000Z

447

E-Print Network 3.0 - australian tropical rainforest Sample Search...  

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

RAINFORESTS OF ... Source: James Cook University, Centre for Tropical Biodiversity and Climate Change Collection: Environmental Sciences and Ecology ; Biology and Medicine 2...

448

E-Print Network 3.0 - australian wet tropics Sample Search Results  

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

OF THE WET ... Source: James Cook University, Centre for Tropical Biodiversity and Climate Change Collection: Environmental Sciences and Ecology ; Biology and Medicine 3...

449

Deep Signatures of Southern Tropical Indian Ocean Annual Rossby Waves* GREGORY C. JOHNSON  

E-Print Network [OSTI]

Deep Signatures of Southern Tropical Indian Ocean Annual Rossby Waves* GREGORY C. JOHNSON NOAA Environmental Laboratory Contribution Number 3671. Corresponding author address: Gregory C. Johnson, NOAA

Johnson, Gregory C.

450

Macrophysical Properties of Tropical Cirrus Clouds from the CALIPSO Satellite and from Ground-based Micropulse and Raman Lidars  

SciTech Connect (OSTI)

Lidar observations of cirrus cloud macrophysical properties over the U.S. Department of Energy Atmospheric Radiation Measurement (ARM) program Darwin, Australia site are compared from the Cloud-Aerosol Lidar and In- frared Pathfinder Satellite Observation (CALIPSO) satellite, the ground-based ARM micropulse lidar (MPL), and the ARM Raman lidar (RL). Comparisons are made using the subset of profiles where the lidar beam is not fully attenuated. Daytime measurements using the RL are shown to be relatively unaffected by the solar background and are therefore suited for checking the validity of diurnal cycles. RL and CALIPSO cloud fraction profiles show good agreement while the MPL detects significantly less cirrus, particularly during the daytime. Both MPL and CALIPSO observations show that cirrus clouds occur less frequently during the day than at night at all altitudes. In contrast, the RL diurnal cy- cle is significantly different than zero only below about 11 km; where it is the opposite sign (i.e. more clouds during the daytime). For cirrus geomet- rical thickness, the MPL and CALIPSO observations agree well and both datasets have signficantly thinner clouds during the daytime than the RL. From the examination of hourly MPL and RL cirrus cloud thickness and through the application of daytime detection limits to all CALIPSO data we find that the decreased MPL and CALIPSO cloud thickness during the daytime is very likely a result of increased daytime noise. This study highlights the vast im- provement the RL provides (compared to the MPL) in the ARM program's ability to observe tropical cirrus clouds as well as a valuable ground-based lidar dataset for the validation of CALIPSO observations and to help im- prove our understanding of tropical cirrus clouds.

Thorsen, Tyler J.; Fu, Qiang; Comstock, Jennifer M.; Sivaraman, Chitra; Vaughan, Mark A.; Winker, D.; Turner, David D.

2013-08-27T23:59:59.000Z

451

Surface and free tropospheric sources of methanesulfonic acid over the tropical Pacific Ocean  

SciTech Connect (OSTI)

The production of sulfate aerosols through marine sulfur chemistry is critical to the climate system. However, not all sulfur compounds have been studied in detail. One such compound is methanesulfonic acid (MSA). In this study, we use a one-dimensional chemical transport model to analyze observed vertical profiles of gas-phase MSA during the Pacific Atmospheric Sulfur Experiment (PASE). The observed sharp decrease in MSA from the surface to 600m implies a surface source of 4.0◊107 molecules/cm2/s. Evidence suggests that this source is photolytically enhanced. We also find that the observed large increase of MSA from the boundary layer into the lower free troposphere (1000-2000m) results mainly from the degassing of MSA from dehydrated aerosols. We estimate a source of 1.2◊107 molecules/cm2/s through this pathway. This source of soluble MSA potentially provides an important precursor for new particle formation in the free troposphere over tropics, affecting the climate system through aerosol-cloud interactions.

Zhang, Yuzhong; Wang, Yuhang; Gray, Burton A.; Gu, Dasa; Mauldin, L.; Cantrell, Chris; Bandy, Alan R.

2014-07-28T23:59:59.000Z

452

Impact of Pacific and Atlantic sea surface temperatures on interannual and decadal variations of GRACE land water storage in tropical South America  

E-Print Network [OSTI]

re season severity in South America using sea surface tem-storage in tropical South America, J. Geophys. Res. Atmos. ,hydroclimatology of tropical South America is characterized

de Linage, Caroline; Kim, Hyungjun; Famiglietti, James S; Yu, Jin-Yi

2013-01-01T23:59:59.000Z

453

Multiscale eddy simulation for moist atmospheric convection: Preliminary investigation  

SciTech Connect (OSTI)

A multiscale computational framework is designed for simulating atmospheric convection and clouds. In this multiscale framework, large eddy simulation (LES) is used to model the coarse scales of 100 m and larger, and a stochastic, one-dimensional turbulence (ODT) model is used to represent the fine scales of 100 m and smaller. Coupled and evolving together, these two components provide a multiscale eddy simulation (MES). Through its fine-scale turbulence and moist thermodynamics, MES allows coarse grid cells to be partially cloudy and to encompass cloudyĖclear air mixing on scales down to 1 m; in contrast, in typical LES such fine-scale processes are not represented or are parameterized using bulk deterministic closures. To illustrate MES and investigate its multiscale dynamics, a shallow cumulus cloud field is simulated. The fine-scale variability is seen to take a plausible form, with partially cloudy grid cells prominent near cloud edges and cloud top. From earlier theoretical work, this mixing of cloudy and clear air is believed to have an important impact on buoyancy. However, contrary to expectations based on earlier theoretical studies, the mean statistics of the bulk cloud field are essentially the same in MES and LES; possible reasons for this are discussed, including possible limitations in the present formulation of MES. One difference between LES and MES is seen in the coarse-scale turbulent kinetic energy, which appears to grow slowly in time due to incoherent stochastic fluctuations in the buoyancy. This and other considerations suggest the need for some type of spatial and/or temporal filtering to attenuate undersampling of the stochastic fine-scale processes.

Stechmann, Samuel N., E-mail: stechmann@wisc.edu [Department of Mathematics, University of Wisconsin-Madison (United States); Department of Atmospheric and Oceanic Sciences, University of Wisconsin-Madison (United States)

2014-08-15T23:59:59.000Z

454

The Influence of El Nin~oSouthern Oscillation and the Atlantic Multidecadal Oscillation on Caribbean Tropical Cyclone Activity  

E-Print Network [OSTI]

on Caribbean Tropical Cyclone Activity PHILIP J. KLOTZBACH Department of Atmospheric Science, Colorado State Caribbean basin tropical cyclone activity shows significant variability on interannual as well as multidecadal time scales. Comprehensive statistics for Caribbean hurricane activity are tabulated

Gray, William

455

The occurrence and diversity of tree legumes as influenced by soil properties in selected tropical forests in Costa Rica  

E-Print Network [OSTI]

Legumes play important roles in tropical forests due to their contribution to N?-fixation and nutrient cycling. Our objectives were to determine which soil properties, if any, affect the occurrence and distribution of tree legumes in a tropical wet...

Wesch, Richard Albert

1999-01-01T23:59:59.000Z

456

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

E-Print Network [OSTI]

The Tropical Pacific Warm Pool International Cloud Experiment (TWP-ICE) took place in Darwin, Australia in early 2006. C-band radar data from this experiment were used to characterize tropical anvil areal coverage, height, and thickness during...

Frederick, Kaycee Loretta

2007-04-25T23:59:59.000Z

457

Tropical Africa: Land use, biomass, and carbon estimates for 1980  

SciTech Connect (OSTI)

This document describes the contents of a digital database containing maximum potential aboveground biomass, land use, and estimated biomass and carbon data for 1980 and describes a methodology that may be used to extend this data set to 1990 and beyond based on population and land cover data. The biomass data and carbon estimates are for woody vegetation in Tropical Africa. These data were collected to reduce the uncertainty associated with the possible magnitude of historical releases of carbon from land use change. Tropical Africa is defined here as encompassing 22.7 x 10{sup 6} km{sup 2} of the earth`s land surface and includes those countries that for the most part are located in Tropical Africa. Countries bordering the Mediterranean Sea and in southern Africa (i.e., Egypt, Libya, Tunisia, Algeria, Morocco, South Africa, Lesotho, Swaziland, and Western Sahara) have maximum potential biomass and land cover information but do not have biomass or carbon estimate. The database was developed using the GRID module in the ARC/INFO{sup TM} geographic information system. Source data were obtained from the Food and Agriculture Organization (FAO), the U.S. National Geophysical Data Center, and a limited number of biomass-carbon density case studies. These data were used to derive the maximum potential and actual (ca. 1980) aboveground biomass-carbon values at regional and country levels. The land-use data provided were derived from a vegetation map originally produced for the FAO by the International Institute of Vegetation Mapping, Toulouse, France.

Brown, S. [Environmental Protection Agency, Corvallis, OR (United States). Western Ecology Division; Gaston, G. [Environmental Protection Agency, Corvallis, OR (United States). National Research Council; Daniels, R.C. [ed.] [Oak Ridge National Lab., TN (United States)

1996-06-01T23:59:59.000Z

458

Tropical air mass modification over water (Gulf of Mexico Region)  

E-Print Network [OSTI]

. Scripps Institution of Oceanography, Oceanographic Report No. 9 (Fog Pro)sot) Lopes, M. E. 194S A technique for detailed radiosonde analysis in the tropics. Bull. Amer. Meteor. Soc. , Vol. 29, No. 5. Solot, S. R. 1939 Computations of' depth... represents an aporoxi- mate equilibrium with respect to the surface beneath. Thus, an air mass may be identified by the vertical structure it acquires over a source Willett, H. D. , Papers in Phys. Ocn. and Met. , Vol. II, No. 2, 1943 region. The concept...

Sorgnit, Ernest Frederick

1952-01-01T23:59:59.000Z

459

A Model Evaluation Data Set for the Tropical ARM Sites  

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

This data set has been derived from various ARM and external data sources with the main aim of providing modelers easy access to quality controlled data for model evaluation. The data set contains highly aggregated (in time) data from a number of sources at the tropical ARM sites at Manus and Nauru. It spans the years of 1999 and 2000. The data set contains information on downward surface radiation; surface meteorology, including precipitation; atmospheric water vapor and cloud liquid water content; hydrometeor cover as a function of height; and cloud cover, cloud optical thickness and cloud top pressure information provided by the International Satellite Cloud Climatology Project (ISCCP).

Jakob, Christian

460

The Tropical Warm Pool International Cloud Experiment: Overview  

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:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched Ferromagnetism in Layered NbS2 andThe MolecularPlaceThe AnTheforThe Tropical Warm

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


461

Are tropical fungal endophytes hyperdiverse? Fungal endophytes are ubiquitous fungi that inhabit healthy plant tissues without  

E-Print Network [OSTI]

Are tropical fungal endophytes hyperdiverse? Abstract Fungal endophytes are ubiquitous fungi that inhabit healthy plant tissues without causing disease. Endophytes have been found in every plant species sites in a lowland, moist tropical forest of central Panama, we quantified endophyte colonization

California at Berkeley, University of

462

Thermodynamics of tropical cyclogenesis in the northwest Pacific D. J. Raymond,1  

E-Print Network [OSTI]

Thermodynamics of tropical cyclogenesis in the northwest Pacific D. J. Raymond,1 S. L. Sessions,1 and thermodynamic products were derived from dropsonde and airborne Doppler radar data, with the goal of increasing: Raymond, D. J., S. L. Sessions, and C. Lůpez Carrillo (2011), Thermodynamics of tropical cyclogenesis

Raymond, David J.

463

Shipboard Measurements and Estimations of AirSea Fluxes in the Western Tropical Pacific Ocean  

E-Print Network [OSTI]

Ship­board Measurements and Estimations of Air­Sea Fluxes in the Western Tropical Pacific Ocean E dur­ ing the Tropical Ocean Global Atmosphere (TOGA) Coupled Ocean and Atmospheric Response of the surface­layer turbulence properties are compared with those from previous land and ocean results. Momentum

California at Irvine, University of

464

Microphysical and radiative evolution of aerosol plumes over the tropical North Atlantic Ocean  

E-Print Network [OSTI]

Microphysical and radiative evolution of aerosol plumes over the tropical North Atlantic Ocean] Over the tropical North Atlantic Ocean in the summer, plumes of aerosol extend from Saharan Africa to the Caribbean. The microphysical and radiative evolution of such plumes is studied using a Lagrangian column

Russell, Lynn

465

Relative timing of last glacial maximum and late-glacial events in the central tropical Andes  

E-Print Network [OSTI]

, and CO2. Moreover, as the energetic powerhouse of the earth, the tropics have huge potential to trigger shifts in tropical temperature and precipitation during the Late Pleistocene (ice-core data: Thompson et al., 1995, 1998; lake-core data: Baker et al., 2001a, b; glacial-geologic data: Smith et al., 2005a

Winckler, Gisela

466

SCALAR WIND SPEED AND DIRECTION TROPICAL CYCLONE RETRIEVALS FOR CONICAL SCANNING SCATTEROMETERS  

E-Print Network [OSTI]

SCALAR WIND SPEED AND DIRECTION TROPICAL CYCLONE RETRIEVALS FOR CONICAL SCANNING SCATTEROMETERS--Scatterometer measurements of ocean vector winds (OVW) are significantly degraded in the presence of the precipitation, especially in tropical cyclones. This paper presents a new ocean hurricane/typhoon wind vector retrieval

Hennon, Christopher C.

467

Isentropic Slopes, Downgradient Eddy Fluxes, and the Extratropical Atmospheric Circulation Response to Tropical Tropospheric Heating  

E-Print Network [OSTI]

to Tropical Tropospheric Heating AMY H. BUTLER NOAA/NWS/NCEP/Climate Prediction Center, Camp Springs, Maryland of the midlatitude jets and their associated eddy fluxes of heat and potential vorticity (PV). Experiments run latent heating and thus locally enhanced warming in the tropical troposphere. Here the authors provide

468

Do Gravity Waves Transport Angular Momentum away from Tropical Cyclones? YUMIN MOON AND DAVID S. NOLAN  

E-Print Network [OSTI]

Do Gravity Waves Transport Angular Momentum away from Tropical Cyclones? YUMIN MOON AND DAVID S that gravity waves can transport a significantly large amount of angular momentum away from tropical cyclones-water equations to model gravity waves radiating outward from rapidly rotating inner-core asymmetries. This issue

Nolan, David S.

469

THE EXTENT AND CAUSES OF ILLEGAL LOGGING: AN ANALYSIS OF A MAJOR CAUSE OF TROPICAL  

E-Print Network [OSTI]

THE EXTENT AND CAUSES OF ILLEGAL LOGGING: AN ANALYSIS OF A MAJOR CAUSE OF TROPICAL DEFORESTATION;2 THE EXTENT AND CAUSES OF ILLEGAL LOGGING: AN ANALYSIS OF A MAJOR CAUSE OF TROPICAL DEFORESTATION IN INDONESIA high rates of deforestation in Indonesia. Its extent during 1997-98 is analysed using a materials

470

Characterizing a tropical deforestation wave: a dynamic spatial analysis of a deforestation hotspot in the  

E-Print Network [OSTI]

Characterizing a tropical deforestation wave: a dynamic spatial analysis of a deforestation hotspot deforestation is the major contemporary threat to global biodiversity, because a diminishing extent of tropical of deforestation. How- ever, it is not a random process, but often moves in waves originating from settled areas

Queensland, University of

471

Energy dynamics and modeled evapotranspiration from a wet tropical forest in Costa Rica  

E-Print Network [OSTI]

Energy dynamics and modeled evapotranspiration from a wet tropical forest in Costa Rica H). #12;1. Introduction The energy balance of tropical forests is complex due to feedback mechanisms among.W. Loeschera, *, H.L. Gholza,b , J.M. Jacobsc , S.F. Oberbauerd,e a School of Forest Resources and Conservation

472

Presentation 2.6: Wood waste for energy: lessons learnt from tropical regions Paul Vantomme  

E-Print Network [OSTI]

of forest products with more value adding, and promoting the use of wood waste to increase energy efficiency tropical timber trade · almost 80% of the world's tropical forests ITTO ­ Wood Waste for Energy Working and forest industries GhanaDevelopment of energy alternatives for the efficient utilization of wood

473

Large CO2 disequilibria in tropical lakes Humberto Marotta,1,2  

E-Print Network [OSTI]

Large CO2 disequilibria in tropical lakes Humberto Marotta,1,2 Carlos M. Duarte,2 Sebastian Sobek,3 November 2009. [1] On the basis of a broad compilation of data on pCO2 in surface waters, we show tropical lakes to be, on average, far more supersaturated and variable in CO2 (geometric mean ¬Ī SE pCO2 = 1804

Wehrli, Bernhard

474

VARIABILITY OF FREE TROPOSPHERIC HUMIDITY FROM METEOSAT OVER THE TROPICS: 1983-2005  

E-Print Network [OSTI]

1 , Julien Lémond 2 , Rémy Roca 2 and Laurence Picon 2 1 Centre d'Etude des Environnements Terrestre to the complex mixing of extra tropical and tropical air that modulates the dryness of the area. Preliminary

Brogniez, Hélène

475

Vertical Structure of Tropical Cyclone Rainbands as Seen by the TRMM Precipitation Radar  

E-Print Network [OSTI]

Vertical Structure of Tropical Cyclone Rainbands as Seen by the TRMM Precipitation Radar DEANNA A Measurement Mission satellite's Precipitation Radar (TRMM PR) show the vertical structure of tropical cyclone separated by the melting layer. The ice layer is a combination of particles imported from the eyewall

Houze Jr., Robert A.

476

Influence of local and remote SST on North Atlantic tropical cyclone potential intensity  

E-Print Network [OSTI]

Influence of local and remote SST on North Atlantic tropical cyclone potential intensity Suzana J of local and remote sea surface temperature (SST) on the tropical cyclone potential intensity in the North Atlantic using a suite of model simulations, while separating the impact of anthropogenic (external

Camargo, Suzana J.

477

The increasing intensity of the strongest tropical James B. Elsner1  

E-Print Network [OSTI]

cyclones. We note separate upward trends in the estimated lifetime-maximum wind speeds of the veryLETTERS The increasing intensity of the strongest tropical cyclones James B. Elsner1 , James P. Kossin2 & Thomas H. Jagger1 Atlantic tropical cyclones are getting stronger on average, with a 30-year

Kossin, James P.

478

Sensitivity of an Ocean-Atmosphere Coupled Model to the Coupling Method : Study of Tropical Cyclone  

E-Print Network [OSTI]

Sensitivity of an Ocean-Atmosphere Coupled Model to the Coupling Method : Study of Tropical Cyclone) in a realistic configuration aiming at simulating the genesis and propagation of tropical cyclone Erica and Oceanic Coupled Models (AOCMs) which account for important air-sea feedbacks. Separate integrations

Recanati, Catherine

479

Tropical Cyclone and Monsoon-Induced Rainfall Variability in Taiwan JAU-MING CHEN  

E-Print Network [OSTI]

Tropical Cyclone≠ and Monsoon-Induced Rainfall Variability in Taiwan JAU-MING CHEN Institute March 2010) ABSTRACT This study investigates the interannual variability of tropical cyclone (TC the relative effects of TCs and monsoons, local rainfall in Taiwan is separated into two subcomponents: TC

Li, Tim

480

Modulation of North Pacific Tropical Cyclone Activity by the2 Three Phases of ENSO3  

E-Print Network [OSTI]

1 1 Modulation of North Pacific Tropical Cyclone Activity by the2 Three Phases of ENSO3 4 Hye-Mail: hyemi.kim@eas.gatech.edu29 30 #12;2 Abstract30 Pacific Ocean warming has been separated into two modes (EPC), these three regimes are shown to have different impacts on34 tropical cyclone activity over

Webster, Peter J.

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


481

Use of a Genesis Potential Index to Diagnose ENSO Effects on Tropical Cyclone Genesis  

E-Print Network [OSTI]

Use of a Genesis Potential Index to Diagnose ENSO Effects on Tropical Cyclone Genesis SUZANA J influence on tropical cyclone activity. The authors examine how different environmental factors contribute. Composite anomalies of the genesis potential index are produced for El NiŮo and La NiŮa years separately

Sobel, Adam

482

Sensitivity of Ocean-Atmosphere Coupled Models to the Coupling Method : Example of Tropical Cyclone  

E-Print Network [OSTI]

Sensitivity of Ocean-Atmosphere Coupled Models to the Coupling Method : Example of Tropical Cyclone and propagation of tropical cyclone Erica. Sensitiv- ity tests to the coupling method are carried out-sea feedbacks. Separate integrations of the Corresponding author. Phone: +33 (0)4 76 51 48 60 Fax: +33 (0)4 76

483

Vertical Structure of Tropical Cyclone Rainbands as seen by the TRMM Precipitation Radar  

E-Print Network [OSTI]

1 Vertical Structure of Tropical Cyclone Rainbands as seen by the TRMM Precipitation Radar Deanna A (TRMM PR) show the vertical structure of tropical cyclone rainbands. Radar-echo2 statistics show that rainbands have a two-layered structure, with distinct modes separated by the3 melting layer. The ice layer

Houze Jr., Robert A.

484

Vertical Structure of Tropical Cyclone Rainbands as seen by the TRMM Precipitation Radar  

E-Print Network [OSTI]

1 Vertical Structure of Tropical Cyclone Rainbands as seen by the TRMM Precipitation Radar Deanna A's Precipitation Radar (TRMM PR) show the vertical structure of tropical cyclone rainbands. Radar-echo statistics show that rainbands have a two-layered structure, with distinct modes separated by the melting layer

Houze Jr., Robert A.

485

The relative importance of tropical variability forced from the North Pacific through ocean pathways  

E-Print Network [OSTI]

forced through the atmosphere? To address this question, in this study we use an anomaly-coupled model), and with coupling con- fined to the Tropics and wind stress and heat fluxes in the North Pacific specified by output impact the tropics through ocean pathways. These two signals are forced by wind stress and surface heat

Solomon, Amy

486

SUMMARY OF 2007 ATLANTIC TROPICAL CYCLONE ACTIVITY AND VERIFICATION OF AUTHOR'S SEASONAL AND MONTHLY FORECASTS  

E-Print Network [OSTI]

10 12.25 8 5.75 Accumulated Cyclone Energy (ACE) (96.2) 130 170 170 150 148 100 68 Net Tropical't press us too hard on future events!!" 3 #12;DEFINITIONS Accumulated Cyclone Energy ­ (ACE) A measureSUMMARY OF 2007 ATLANTIC TROPICAL CYCLONE ACTIVITY AND VERIFICATION OF AUTHOR'S SEASONAL

Gray, William

487

Influence of Western North Pacific Tropical Cyclones on Their Large-Scale Environment  

E-Print Network [OSTI]

water vapor, and sea surface tem- perature (SST)] on an index of TC activity [accumulated cyclone energyInfluence of Western North Pacific Tropical Cyclones on Their Large-Scale Environment ADAM H. SOBEL) tropical cyclones (TCs) on their large-scale environment by lag regressing various large-scale climate

Sobel, Adam

488

Co-variability of tropical cyclones in the North Atlantic and the eastern North Pacific  

E-Print Network [OSTI]

of accumulated cyclone energy (ACE) in the ENP. Therefore, we calculate the NA and ENP ACE indices by summingCo-variability of tropical cyclones in the North Atlantic and the eastern North Pacific Chunzai; published 30 December 2009. [1] In the Western Hemisphere, tropical cyclones (TCs) can form and develop

Wang, Chunzai

489

The Intraseasonal Oscillation and the Energetics of Summertime Tropical Western North Pacific  

E-Print Network [OSTI]

The Intraseasonal Oscillation and the Energetics of Summertime Tropical Western North Pacific University of New York Albany, New York Journal of the Atmospheric Sciences Submitted October 14, 2002 the energetics of tropical depression (TD)-type disturbances. An energetics analysis is conducted with NCEP

Maloney, Eric

490

P 3.1 TROPICAL CYCLONE TORNADO RECORDS FOR THE MODERNIZED NWS ERA Roger Edwards1  

E-Print Network [OSTI]

is attributed to a combination of technological advances in documentation capabilities (e.g., digital camerasP 3.1 TROPICAL CYCLONE TORNADO RECORDS FOR THE MODERNIZED NWS ERA Roger Edwards1 Storm Prediction and BACKGROUND Tornadoes from tropical cyclones (hereafter TCs) pose a specialized forecast challenge at time

491

Stoichiometry of nutrient recycling by vertebrates in a tropical stream: linking species identity and  

E-Print Network [OSTI]

REPORT Stoichiometry of nutrient recycling by vertebrates in a tropical stream: linking species in recycling nutrients, thus providing a mechanism for how animal species identity mediates ecosystem processes) recycled nitrogen (N) and phosphorus (P) in a tropical stream supports stoichiometry theory. Mass

Flecker, Alex

492

Net ecosystem fluxes of isoprene over tropical South America inferred from Global Ozone Monitoring Experiment (GOME)  

E-Print Network [OSTI]

Net ecosystem fluxes of isoprene over tropical South America inferred from Global Ozone Monitoring estimate isoprene emissions over tropical South America during 1997­2001 using column measurements (ATSR) firecounts and GOME NO2 columns. We find that South America can be split into eastern and western

Chance, Kelly

493

Vegetation and Fire at the Last Glacial Maximum in Tropical South America  

E-Print Network [OSTI]

Chapter 4 Vegetation and Fire at the Last Glacial Maximum in Tropical South America Francis E temperatures. Keywords Charcoal · Last Glacial Maximum · pollen · Quaternary · tropical South America F-mail: Francis.Mayle@ed.ac.uk 89F. Vimeux et al. (eds.), Past Climate Variability in South America

Binford, Michael W.

494

Characterization of Throughfall Heterogeneity in a Tropical Pre-Montane Could Forest in Costa Rica  

E-Print Network [OSTI]

CHARACTERIZATION OF THROUGHFALL HETEROGENEITY IN A TROPICAL PRE-MONTANE CLOUD FOREST IN COSTA RICA An Undergraduate Research Scholars Thesis by AMELIE CECILE BERGER Submitted to Honors and Undergraduate Research Texas A... .......................................................................................................4 Tropical forest hydrology ........................................................................................7 Study site: watershed near San Isidro, Costa Rica .................................................13 Quantification...

Berger, Amelie Cecile

2013-09-26T23:59:59.000Z

495

Climate change and tropical Andean glaciers: Past, present and future Mathias Vuille a,b,  

E-Print Network [OSTI]

, Peru and Bolivia give a detailed and unequivocal account of rapid shrinkage of tropical Andean glaciers the tropical glacier energy balance through its sensitivity to changes in atmospheric humidity (which governs influences the energy balance, albeit not through the sensible heat flux, but indirectly through fluctuations

Massachusetts at Amherst, University of

496

Proper orthogonal decomposition approach and error estimation of mixed finite element methods for the tropical Pacific Ocean  

E-Print Network [OSTI]

for the tropical Pacific Ocean reduced gravity model Zhendong Luo a , Jiang Zhu b , Ruiwen Wang b , I.M. Navon c Available online 8 May 2007 Abstract In this paper, the tropical Pacific Ocean reduced gravity model and the insufficient knowledge of air­sea exchange processes. The tropical Pacific Ocean reduced gravity model

Navon, Michael

497

InsideIllinoisMay 5, 2011 Vol. 30, No. 20  

E-Print Network [OSTI]

. Meteorologists have seen large advances in forecasting technology to track the poten- tial path of tropical storms suddenly transform into much stronger cyclones or hurricanes. "Rapid intensification means a moder techniques to inves- tigate a convective ring structure that has been observed in tropical cyclones. "What

Lewis, Jennifer

498

Autecology of Vibrio vulnificus and Vibrio parahaemolyticus in tropical waters  

SciTech Connect (OSTI)

Water and shellfish samples collected from estuaries, mangroves, and beaches along the coast of Puerto Rico were examined for Vibrio vulnificus and Vibrio parahaemolyticus. An array of water quality parameters were also measured simultaneous with bacteria sampling. Both species of vibrio were associated with estuary and mangrove locations, and neither was isolated from sandy beaches. Densities of V. vulnificus were negatively correlated with salinity, 10--15 ppt being optimal. V. parahaemolyticus was isolated from sites with salinities between 20 and 35 ppt, the highest densities occurring at 20 ppt. Densities of Vibrio spp. and V. parahaemolyticus for a tropical estuary surpassed those reported for temperate estuaries by several orders of magnitude. Both densities of total Vibrio spp. and V. parahaemolyticus in the water were directly related to densities of fecal coliforms, unlike V. vulnificus. The incidence of ONPG(+) strains among sucrose({minus}) Vibrio spp. served as an indicator of the frequency of V. vulnificus in this group. More than 63% of the V. vulnificus isolated were pathogenic. V. vulnificus and V. parahaemolyticus occupy clearly separate niches within the tropical estuarine-marine ecosystem.

Rivera, S.; Lugo, T.; Hazen, T.C. [Univ. of Puerto Rico, Rio Piedras (Puerto Rico)

1988-12-31T23:59:59.000Z

499

Convective Mixing in the Earth's P. E. Van Keken  

E-Print Network [OSTI]

. In addition, various geochemical observations suggest an important role for oceanic crust recycling acceptance of these fundamental problems of the classical layered mantle model has led the proposition

van Keken, Peter

500

Observed Synoptic-Scale Variability during the Developing Phase of an ISO over the Indian Ocean during MISMO  

E-Print Network [OSTI]

Observed Synoptic-Scale Variability during the Developing Phase of an ISO over the Indian Ocean A case study of an intraseasonal oscillation (ISO) is investigated in the period leading up to its for a convectively active phase of the ISO. The prominent shallow heating during this period may explain the rather

Johnson, Richard H.