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Brian J. Hoskins and Gui-Ying Yang

1. Introduction The possible forcing of the tropical atmosphere from higher latitudes was proposed by Charney (1963) . However, Charney (1969) showed that only Rossby waves with westward phase speed greater than that of the zonally averaged westward (easterly) zonal flow could propagate. Since these waves have little energy, it was assumed the relevant problem for high-latitude forcing of the Tropics became that of absorption of stationary and eastward-moving Rossby waves at critical lines

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Ian Kraucunas and Dennis L. Hartmann

changes in the shallow-water response to tropical eddy forcing, including the formation of an extratropical wave train when the mean winds are westerly and the layer depth is sufficiently large. Lau and Lim (1984) extended this analysis by considering the combined effects of spherical geometry, nonlinearity, and realistic mean winds. Subsequent studies of stationary waves in the upper troposphere have mainly focused on either the extratropical response to tropical forcing or the equatorward

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Leo J. Donner and Hsiao-Lan Kuo

1 OCTOBER 1984 LEO J. DONNER AND HSIAO-LAN KUO 2849Radiative Forcing of Stationary Planetary Waves LEO J. DONNER National Center for Atmospheric Research, 1 Boulder, CO 80307 HSIAO-LAN KUO Department of the Geophysical Sciences, The University of Chicago, Chicago, IL 60637 (Manuscript received 9 January 1984, in final form 5 July 1984

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Matthew Newman, Prashant D. Sardeshmukh, and Cécile Penland

, though possible, is not a frequent occurrence in the atmosphere and cannot by itself explain the general characteristics of observed low-frequency variability on timescales of longer than 10 days. Taken together, Papers I and II suggest that the observed growth of low-frequency anomalies in the troposphere is not predominantly due to barotropic energy transfers from the ambient flow. However, these papers were concerned with the unforced problem, whereas SWB allowed some role for forcing. As they put

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Hye-Yeong Chun, Hyun-Joo Choi, and In-Sun Song

forced gravity waves can contribute to momentum forcing required to drive the quasi-biennial oscillation and semiannual oscillation ( Alexander and Holton 1997 ; Sassi and Garcia 1997 ). There are several numerical modeling studies of convectively forced gravity waves and their generation mechanisms. Pandya and Alexander (1999) showed that the spectral characteristics of convective gravity waves in a quasi-linear simulation forced by diabatic forcing alone is similar to that in a fully nonlinear

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Yang Zhang and Peter H. Stone

) , Cehelsky and Tung (1991) , Lindzen (1993) , and Zurita and Lindzen (2001) . Baroclinic adjustment suggested a tendency of the baroclinic eddies to homogenize the mean flow PV gradient and proposed a preferred equilibrium state as well as a strong feedback between the eddy heat fluxes and the temperature structure. In the baroclinic adjustment scenario, the eddy fluxes are sensitive to the variation of the external forcing (i.e., seasonal forcing and climate change) but the structure of the mean state

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Irina Sandu, Jean-Louis Brenguier, Olivier Geoffroy, Odile Thouron, and Valery Masson

different aerosol properties usually have different histories, which lead to systematic differences in the meteorology, making it difficult, if not impossible, to isolate the effect of the aerosol. Measurements of the large-scale forcings are not accurate enough, and our understanding of the dynamics of stratocumulus is not complete enough, to precisely predict what the LWP of a cloud layer should be. To illustrate this drawback, consider a STBL with a cloud base temperature of about 20°C and a cloud

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Michael T. Montgomery and John Persing

. (2001 , 106–107), for example, explained the dynamical importance of the nonlinear boundary layer in hurricane spinup as follows: As the storm deepens, the cross-isobaric radial inflow in the [marine boundary layer] transports more [absolute angular momentum] from the hurricane environment into the eyewall region than frictional dissipation. The major radial inflow decelerates as it approaches the [radius of maximum wind] where the centrifugal force exceeds [the radial pressure gradient force

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James R. Holton

942 JOURNAL OF THE ATMOSPHERIC SCIENCES VO~-UME31Forcing of Mean Flows by Stationary Waves~ J~KES R. HOLTON2Dept. of Atmospheric Sciences, University of Washington, Seattle 98195(Manuscript received 1 February 1974)ABSTRACT It is shown that in the absence of dissipation or of critical levels where the mean zonal flow vanishes thefordng of the mean zonal flow by linearized, quasi-static, stationary

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Simona Bordoni and Tapio Schneider

forcing undergo transitions from a linear, viscous regime to a nonlinear, angular-momentum-conserving regime beyond a threshold forcing value; they suggested that this threshold behavior may account for the rapid onset of monsoons. The nonlinear axisymmetric theory of Plumb and Hou (1992) has been extended in several studies to account for the influences of moist convection ( Emanuel 1995 ; Zheng 1998 ), of a subtropical continent ( Privé and Plumb 2007a , b ), and of moisture–dynamics feedbacks

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