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Nicholas K. H. Yeung, Steven C. Sherwood, Alain Protat, Todd P. Lane, and Christopher Williams

produce coherent updrafts and downdrafts via mesoscale dynamical mechanisms ( Rotunno et al. 1988 ). Using a series of axisymmetric numerical cloud simulations, a recent study suggests that in a dry environment, a small initial cloud radius would produce an isolated rising thermal, while a moderate-to-large radius would lead to a succession of thermal pulses ( Peters et al. 2020 ). In contrast, a moderate-to-large radius in a moist environment would support plume-like behavior. Thus, while “hot towers

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Richard C. Igau, Margaret A. LeMone, and Dingying Wei

convective cores have sizes and vertical velocities similar to cores sampled over other parts of the tropical and subtropical oceans, except that the updraft cores have slightly lower virtual temperatures and the downdraft cores appear to have higher virtual temperatures, relative to the environment. In section 4 , we examine 16 of the strongest downdraft cores to explore what makes the downdraft-core virtual temperatures so high in COARE, including the differences between the Ophir instrument and

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Joshua B. Wadler, David S. Nolan, Jun A. Zhang, and Lynn K. Shay

inflow layer can entrain into the eyewall updrafts and decrease the efficiency of the TC heat engine. With convective downdrafts in TCs being widely studied using observations (e.g., Barnes et al. 1983 ; Powell 1990 ; Barnes and Powell 1995 ; Didlake and Houze 2009 , 2013 ; Cione et al. 2000 , 2013 ; Eastin et al. 2012 ; Barnes and Dolling 2013 ; Molinari et al. 2013 ; Dolling and Barnes 2014 ; Zhang et al. 2017 ; Nguyen et al. 2019 ), recent efforts have tried to further understand

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Kuan-Man Xu and David A. Randall

1. Introduction Aircraft observations of cumulus drafts have revealed the statistical distributions of updraft and downdraft vertical velocities, mostly for the lower troposphere and some for the middle troposphere ( Byers and Braham 1949 ; Gray 1965 ; LeMone and Zipser 1980 ; Jorgensen et al. 1985 ; Jorgensen and LeMone 1989 ; Lucas et al. 1994a ; Wei et al. 1998 ; Igau et al. 1999 ). The statistics of updrafts and downdrafts are substantially different between tropical

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Robert A. Houze Jr. and Chee-Pong Cheng

AUGUST 1981 ROBERT A. HOUZE, JR., AND CHEE-PONG CHENG 1751Inclusion of Mesoscale Updrafts and Downdrafts in Computations of Vertical Fluxes by Ensembles of Tropical Clouds ROBERT A. HOUZE, JR., AND CHEE-PONG CHENGDepartment of Atmospheric Sciences, University of Washington, Seattle, 98195(Manuscript received 17 July 1980, in final form 14 April 1981) ABSTRACT Ensembles of convective

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Siri Jodha Singh Khalsa and Gary K. Greenhut

2550 JOURNAL OF THE ATMOSPHERIC SCIENCES VOL. 42, NO. 23Conditional Sampling of Updrafts and Downdrafts in the Marine Atmospheric Boundary Layer SIRI JODHA SINGH K. HALSACooperative Institute for Research in Environmental Sciences, University of Colorado/NOA,4. Boulder, CO 80309 GARY K. GREENHUTNOA,4 Environmental Research Laboratories, Boulder, CO 80303(Manuscript received 29 March 1985

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Cody Kirkpatrick, Eugene W. McCaul Jr., and Charles Cohen

parameterizations employed ( Cohen and McCaul 2006 ). Adlerman and Droegemeier (2005) clarified the importance of environmental vertical wind shear, finding that “the strongest [mesocyclones] occur when the largest shears are confined to the shallowest depths.” Many of these studies, however, focused on the relationship between environmental conditions and the storm updraft. In this work we also consider the effects of these parameters on the downdraft. Downdraft outflows can help promote tornadogenesis (e

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Gary K. Greenhut and Siri Jodha Singh Khalsa

AUGUST I982 GARY K. GREENHUT AND SIRI JODHA SINGH KHALSA 1803Updraft and Downdraft Events in the Atmospheric Boundary Layer Over the Equatorial Pacific Ocean GARY K. GREENHUTO~ce of Weather Research and Modification, Environmental Research Laboratories/NOAA, Boulder, CO 80303 SIRI JODHA SINGH KHALSACooperative Institute for Research in Environmental Sciences, University of

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P. Kollias, B. A. Albrecht, R. Lhermitte, and A. Savtchenko

1. Introduction Fair-weather cumuli are fundamental in regulating the vertical structure of water vapor and entropy in the lowest 2 km of the earth's atmosphere over vast areas of the oceans. Thus the effects of these small-scale circulations must be parameterized in large-scale models ( Tiedke et al. 1989 ). Consequently, entrainment and precipitation processes as they relate to updraft and downdraft circulations in the boundary layer clouds are critical for even the most simplified and highly

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Tsuyoshi Nitta

AUGUST 1977 TSUYOSHI NITTA 1163Response of Cumulus Updraft and Downdraft to GATE A/B-Scale Motion Systems TSUYOSHI NITTA~Department of Atmospheric Sciences, University of California, Los Angeles 90024(Manuscript received 26 January 1977, in revised form 2 May 1977) ABSTRACT Large-scale mass, heat and moisture budgets have been

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