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Zhuo Wang, C-P. Chang, Bin Wang, and Fei-Fei Jin

location of the tropical forcing. An equatorial heating may directly excite equatorially trapped baroclinic Rossby waves but is inefficient in exciting barotropic-type responses directly. Lim and Chang (1986) found that vertical shear, differential damping, and the planetary boundary layer enable an energy transfer from the heating-forced baroclinic waves to deep barotropic modes, which allows a teleconnection between the Tropics and the extratropics. Using a two-level model, Wang and Xie (1996

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II. Variation of the Tropospheric Mean Structure With Season and Differences Between Hemispheres


transports and in the mean meridional circulation.The model indicates how the annual oscillation of temperature in t,he equatorial lower stratosphere, with lowesttemperatures in January, derives from the difference between the upward branches of the July and t.he January winterhemisphere Hadlep cell. The semiannual oscillation in winds and temperatures in the Tropics is largely accounted forby the model in terms of the longitudinally averaged tropical rain belt migrating between summer hemispheres.1

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John F. Gamache and Robert A. Houze Jr.

JULY 1983 JOHN F. GAMACHE AND ROBERT A. HOUZE, JR. 1835Water Budget of a Mesoscale Convective System in the Tropics~ JOHN F. GAMACHE AND ROBERT A. HOUZE, JR.Department of Atmospheric Sciences, University of Washington, Seattle, W.4 98195(Manuscript received 8 November 1982, in final form 9 March 1983)ABSTRACT A squall-line cloud cluster observed in the Global Atmospheric Research Program's Atlantic TropicalExperiment (GATE) is studied

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Arthur F. Kruger and Jay S. Winston

VOL. 103, NO. 6 M O NTHLY \VEATHE-R R EVI E\V ' JUNE 1975Large-Scale Circulation Anomalies Over the Tropics during 1971-72 ART~U-R F. K~tmo~ AND JAY S. WINSTONWational Environmental Satellite Service, 2V OAA, Washington, D. C. 20233(Manuscript received 12 November 1974; in revised form 7 February 1975)ABSTRACT The authors have been monitoring the large-scale circulation over the tropics since 1968 through use

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April 1966Walter James Koss231OBJECTIVE ANALYSIS OF PRESSURE HEIGHT DATA FOR THE TROPICSWALTER JAMES KO%National Hurricane Research Laboratory, ESSA, Miami, Fla.ABSTRACTA method for objectively analyzing the geopotential height field on a constant pressure surface using reportedupper-air data is described. Special attention is given to the analysis in data sparse regions, in particular, the Tropics.Wind-height relationships are used to augment the reported data by extrapolation of the reported

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Ronald B. Smith, Justin R. Minder, Alison D. Nugent, Trude Storelvmo, Daniel J. Kirshbaum, Robert Warren, Neil Lareau, Philippe Palany, Arlington James, and Jeffrey French

made on thermally driven island convection in the tropics (e.g., Carey and Rutledge 2000 ; Wilson et al. 2001 ; Sobel et al. 2011 ; Robinson et al. 2011 ). In contrast, the Dominica Experiment (DOMEX) was designed to study orographic precipitation in the tropics with cumulus triggering by forced ascent in unblocked flow. Dominica (15°N, 61°W) lies in the eastern Caribbean in the Lesser Antilles chain of volcanic islands ( Fig. 1 ). Its terrain is dominated by the 1.4-km peaks of Mt. Diablotin

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T. N. Krishnamurti, C. Gnanaseelan, and A. Chakraborty

introduced by reducing the blackbody emittance for high clouds (partial blackbody). Those artificial fixes did produce the correct phases for rain over the eastern Tibetan Plateau (afternoon hours) and the eastern foothills of Himalayas (early morning hours). Those fixes in fact turned out to be disastrous for the rest of the Tropics especially over Brazil where the model failed to provide the afternoon showers. This demonstrated some of the modeling problems for the diurnal change. In general the

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Mark D. Zelinka and Dennis L. Hartmann

subsiding environment ( Yanai et al. 1973 ). Because it is the ensemble of transient deep convective processes that results in the measured mean ascent in the tropics, understanding the large-spatial-scale and long-temporal-scale tropical circulation requires understanding deep convective processes. In addition to its dynamical importance for the tropical circulation, deep convection is the primary source of high clouds and free-tropospheric water vapor, which strongly impact the radiation budget of the

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Brant Liebmann, M. Chelliah, and H. M. van den Dool

) anomalies in the tropics on many differenttime scales during 1974-86. We calculate "one-lag autoqo, rrelations" by constructing nonovefiapping 1-, 15-,and 60-day averages and calculating the correlation at every grid point between every time average and thefollowing average for the entire dataset. One-day averages produce the largest local autocorrelations everywhereexcept over the equatorial Pattie. Large autocorrelations using 15-day averages are confined to the equatorialPacific, but large

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K. P. Sooraj, H. Annamalai, Arun Kumar, and Hui Wang

ability to predict tropical climate variations with some success ( Kang and Shukla 2006 ; Kirtman and Pirani 2009 ). Here, we examine the seasonal forecast performance of the National Centers for Environmental Prediction’s (NCEP) Coupled Forecast System (CFS) over the tropics and also over the U.S. Affiliated Pacific Islands (USAPI). The hypothesis that boundary conditions such as sea surface temperature (SST), snow cover, and soil wetness have significant influence on seasonal mean tropical

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