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Kaushik Srinivasan and W. R. Young

1. Introduction In this work we consider a canonical linear problem: the stochastically forced, linearized β -plane vorticity equation with a background mean shear γ : The eddy vorticity is related to the eddy streamfunction by , and the eddy velocities are . The random forcing ξ ( x , y , t ) is spatially homogenous and white noise in time and is characterized more precisely in section 2 . Drag, with coefficient μ , is the dissipative mechanism. Our main concern is the eddy transport

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Joonsuk Lee, Ping Yang, Andrew E. Dessler, Bo-Cai Gao, and Steven Platnick

convective blowoff, whereas the other half were associated with in situ formation. Because of the high frequency of occurrence of thin cirrus clouds, the effect of these clouds on the earth’s radiation budget can be significant. For example, these clouds, located high in the atmosphere, absorb longwave radiation but emit radiation at very low temperatures, producing local heating by a few degrees per day ( Jensen et al. 1996 ; McFarquhar et al. 2000 ) and net positive cloud radiative forcing on the

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Tiehan Zhou, Marvin A. Geller, and Wuyin Lin

velocity on a given pressure level is controlled exclusively by the distribution of the wave drag above that level. The downward control principle ( Haynes et al. 1991 ) is conventionally formulated as where is the residual mean vertical velocity, φ the latitude, z the log pressure height, ρ 0 the reference density profile, a the radius of the earth, D the wave forcing, the zonal mean angular momentum, the zonal mean zonal wind, Ω the angular velocity of the earth, and dz ′ the

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Christopher M. Rozoff, James P. Kossin, Wayne H. Schubert, and Pedro J. Mulero

material rate of change of θ ρ , and F the frictional force per unit mass. It should be noted that (1) does not differ greatly from the PV equation for a dry atmosphere because the total density ρ is approximately equal to the dry air density and the virtual potential temperature θ ρ is approximately equal to the dry potential temperature. Based on (1) , we can say that there are three aspects to understanding the PV structure in hurricanes: (i) the advective aspects embodied in the D / Dt

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Rolando R. Garcia and John E. Geisler

OCTOBER 1981 ROLANDO R. GARCIA AND JOHN E. GEISLER 2187Stochastic Forcing of Small-Amplitude Oscillations in the Stratosphere ROLANDO R. GARCIA AND JOHN E. GEISLER~National Center for Atmospheric Research? Boulder, CO 80307(Manuscript received 12 March 1981, in final form 11 May 1981)ABSTRACT A quasi-geostrophic/g-plane channel model is used to study the response of the stratosphere to planetarywaves forced at the

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Yizhe Peggy Bu, Robert G. Fovell, and Kristen L. Corbosiero

differ with respect to the amounts and relative distributions of hydrometeors, such as cloud ice, snow, cloud droplets, etc. ( Fovell et al. 2010b ). These particles have different effective sizes that determine how they interact with longwave (LW) and shortwave (SW) radiation (e.g., Dudhia 1989 ). Herein, we demonstrate how and why cloud–radiative forcing (CRF), the modulation of atmospheric radiation owing to hydrometeors, can influence tropical cyclones. The specific focus is on storm structure

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Wojciech W. Grabowski

others. However, in nature, convective clouds continuously interact with their surroundings through gravity waves and detrainment that modify their environment (e.g., Bretherton and Smolarkiewicz 1989 ). These interactions affect development of subsequent clouds. Thus, it is irrelevant what the first cloud does, but what matters is a response of an ensemble of clouds to realistic forcings averaged over many cloud realizations. (An exception to this argument might be when the first cloud causes a

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Junyan Xiong, Jun Yang, and Ji Nie

; for example, a doubling of atmospheric pressure produces a warming of ~7 K ( Charnay et al. 2013 ), and a pressure of 2.4 bar N 2 leads to surface warming of 9.7 K ( Wolf and Toon 2013 ). In this study, we mainly consider the scenario in which the atmospheric mass change is due to changes in the masses of radiatively inactive species (i.e., N 2 and O 2 ), thus excluding direct radiative forcing due to changes in the masses of radiatively active species. We explore the dependence of climate on

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Xun Zhu and James R. Holton

620 JOURNAL OF THE ATMOSPHERIC SCIENCES VOL. 44, No. 3Mean Fields Induced by Local Gravity-Wave Forcing in the Middle Atmosphere XUN ZHU AND JAMES R. HOLTON Department of Atmospheric Sciences, University of Washington, Seattle. WA 98195 (Manuscript received 29 May. 1986, in final form 25 September 1986) ABSTRACT We examine the role ofgeostrophic adjustment in the middle

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Nikki C. Privé and R. Alan Plumb

flow at low levels. Using a linear shallow-water model, Gill (1980) found that a localized prescribed forcing in the off-equatorial Tropics induces a cross-equatorial circulation similar to the observed monsoon flow. However, Held and Hou (1980) , Lindzen and Hou (1988) , and Plumb and Hou (1992) determined the axisymmetric Hadley circulation to be fundamentally nonlinear, and predicated upon the conservation of angular momentum in the free troposphere. The intent of this work is to explore

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