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Xun Zhu

!5 DECEMBER 1994 Z H U 3593An Accurate and Efficient Radiation Algorithm for Middle Atmosphere Models XUN ZHUDepartment of Earth and Planetary Sciences, The Johns Hopkins University, Baltimore, Maryland(Manuscript received 6 August 1993, in final form 10 May 1994) ABSTRACT An accurate, efficient, and

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Tiffany A. Shaw and Theodore G. Shepherd

1. Introduction The importance of gravity waves in determining the large-scale structure of the middle atmosphere is well established ( Fritts and Alexander 2003 ). Gravity waves transport angular momentum from their source regions in the troposphere and exert a torque where they dissipate in the middle atmosphere. The angular momentum transfer due to small-scale gravity waves [gravity wave drag (GWD)] is not explicitly resolved and thus must be parameterized in general circulation models (GCMs

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Timothy J. Dunkerton

the equatorial middle atmosphere at the solstices. It is shown that the stability ofthis region depends primarily on two unknowns. First, there is the question of whether eddy diffusioncan be regarded as stabilizing, or whether this diffusion actually arises from the instability itself. Second,because the diabatlc circulation would appear to induce a cross-equatorial shear much greater than thatobserved, or than that modeled in Holton and Wehrbein (1980), it appears that the gravity waveinduced

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Rolando R. Garcia

1 JUNE 1991 P, OLANDO R. GARC1A 1405Parameterization of Planetary Wave Breaking in the Middle Atmosphere ROLANDO R. GARCIANational Center for Atmospheric Research, * Boulder, Colorado(Manuscript received 30 April 1990, in final form 14 January 1991)ABSTRACT A parameterization of planetary wave breaking in the middle atmosphere has been developed and tested ina numerical model which

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Lee S. Elson

I MAY 1990 LEE S. ELSON 1065Satellite Observations of Instability in the Middle Atmosphere LEE S. ELSONJet Propulsion Laboratory, California Institute of Technology, Pasadena, California(Manuscript received 7 July 1989, in final form 6 November 1989)ABSTRACT Data from the Limb Infrared Monitor of the Stratosphere (LIMS) have been used to define zonally averagedbasic

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G. P. Klaassen

1. Introduction Upward-propagating, small-scale gravity waves are thought to play a prominent role in driving the circulation of the middle atmosphere (e.g., see the reviews of Hamilton 1996 ; Fritts and Alexander 2003 ; Kim et al. 2003 ). In the absence of other processes, one would expect these waves to grow in amplitude as they propagate upward, owing to the decrease of density with height ( Hines 1960 ). Nevertheless, it has been shown by VanZandt (1982) and others that averaged power

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Xun Zhu, Jeng-Hwa Yee, Ming Cai, William H. Swartz, Lawrence Coy, Valentina Aquila, Rolando Garcia, and Elsayed R Talaat

1. Introduction The warming of Earth’s surface and lower atmosphere due to increases in greenhouse gases (GHG) is associated with enhanced middle-atmosphere cooling and a possible strengthening of the Brewer–Dobson circulation through radiative–dynamical coupling. Because both the air density and the optical depths of major radiatively active species decrease with altitude, the physical state of the middle atmosphere as represented by various parameters such as temperature and winds is quite

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Jeffrey R. Barnes

VOL. 48, NO. 2 JOURNAL OF THE ATMOSPHERIC SCIENCES 15JANUARY 1991A Simple Nearly Analytic Model of a Gravity Wave Driven Middle Atmosphere Circulation JEFFREY R. BARNESDepartment of Atmospheric Sciences, Oregon State University, Corvallis, Oregon(Manuscript received 8 January 1990, in final form 3 July 1990)ABSTRACT A nearly analytic.model of a gravity wave driven middle atmosphere circulation is formulated

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Peter Hitchcock and Theodore G. Shepherd

the upper stratosphere across a number of comprehensive middle-atmosphere models. The regularity of the zonal-mean evolution during PJO events suggests that the processes responsible are common to all the events, and are thus presumably predictable; indeed, enhanced predictability in the stratosphere has been found following sudden warmings in forecasting case studies ( Mukougawa et al. 2009 ). Since these events have been shown to influence the tropospheric circulation ( Baldwin and Dunkerton

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D. Rind, R. Suozzo, N. K. Balachandran, and M. J. Prather

15FEBRUARY 1990 RIND, SUOZZO, BALACHANDRAN AND PRATHER 475Climate Change and the Middle Atmosphere. Part I: The Doubled CO2 Climate D. RIND NASA Goddard Space Flight Center, Institute for Space Studies, New York R. SUOZZO Sigma Data Service Co?poration, New York, New York N. K. BALACHANDRANLamont-Doherty Geological Observatory of Columbia University, Palisades, New York

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