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D. G. Dritschel and M. E. McIntyre

1. Introduction Chaotic flows in stratified, rotating fluid systems like planetary atmospheres and oceans are often called “turbulent.” However, in such systems there is no such thing as turbulence without waves, a point well brought out in the celebrated paper of Rhines (1975) . One way to appreciate the point is to note that such systems always have background gradients of potential vorticity (PV) and then consider the implications for the momentum and angular momentum budgets. As will be

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Hiroyuki Kurokawa and Taishi Nakamoto

from the condition that the base of the stratosphere is saturated, and the radiation limit of the troposphere is set because the atmospheric structure around the optically thin layer (where “optically thin layer” refers to the layer where the optical depth for the longwave planetary radiation is unity when measured from the top of the atmosphere) is fixed by the tropospheric saturated water vapor pressure condition. Although NHA92 assumed the atmosphere to be transparent to shortwave radiation

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Junjun Liu and Tapio Schneider

computationally feasible for the foreseeable future, both because the scales of eddies in the upper atmosphere are relatively small compared with the planetary scale (hence the large number of jets) and because adjustment time scales of the deep interior are very long (centuries to millennia), requiring long spinup periods. Instead, we employ a simplified approach, focusing on the upper atmospheres, but linking its dynamics to a representation of the MHD drag that in reality occurs at great depth. The angular

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Jonathan L. Mitchell and Spencer A. Hill

1. Introduction Terrestrial atmospheres in which both tropical and extratropical dynamical regimes exist are thought to be common (as on Earth, Mars, and likely many identified exoplanets; e.g., Showman et al. 2014 ). Their atmospheres are neither dominated by zonally banded dynamics as on the gas giants, nor by global Hadley cells as on Venus and Titan. Instead, the Hadley cell descending branches sit roughly in the transitional, subtropical zone. In this planetary context, “subtropical” is

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Paul D. Williams and Christopher W. Kelsall

1. Introduction Zonal jets in planetary atmospheres and oceans affect the transport of heat, momentum, and tracers. Satellite observations show clear evidence of multiple alternating zonal jets extending from the equator to the polar regions in the atmospheres of Jupiter ( Limaye 1986 ) and Saturn ( Sanchez-Lavega et al. 2000 ). In numerical simulations of the atmospheres of Jupiter, Saturn, Uranus, and Neptune, jets are found to emerge spontaneously from random initial conditions, in good

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Mark R. Schoeberl and John H. E. Clark

20 JOURNAL OF THE ATMOSPHERIC SCIENCES VOLUME 37Resonant Planetary Waves in a Spherical AtmosphereMARK R. SCHOEBERLNavul Research Laboratory, Washington, DC 20375JOHN H. E. CLARK'Science Application, Inc., McLean, VA 22102(Manuscript received 9 February 1979, in final form 21 August 1979) ABSTRACTIA global model of planetary wave propagation in a spherical atmosphere is used to examine thespectrum of free or resonant planetary waves of the solstitial stratosphere. These free

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Curt Covey and Gerald Schubert

NOVEMBER 1982CURT COVEY AND GERALD SCHUBERT2397Planetary-Scale Waves in the Venus AtmosphereCURT COVEYNational Center for Atmospheric Research1, Boulder, CO 80307GERALD SCHUBERTDepartment of Earth and Space Sciences, University of California, Los Angeles 90024(Manuscript received 10 May 1982, in final form 16 July 1982)ABSTRACTA numerical model of planetary-scale waves in Venus' atmosphere is used to simulate observed wave-likecloud features such as the dark horizontal Y. The model is based on

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G. P. Horedt

1410JOURNAL OF.THE ATMOSPHERIC SCIENCES NO. TES AND CORRESPONDENCE On the Maximum Exospheric Temperature of Hydrogen-Dominated Planetary Atmospheres G. P. HOREDT Lunar and Planetary Laboratory, University of ~4rizona, Tucson 85721 16 July 1981 and 8 January 1982 ABSTRACT It is shown that under static conditions the maximum temperature attainable in the exosphcres of hydrogen-dominated planetary atmospheres is of

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Tapio Schneider and Junjun Liu

atmosphere to the planet’s center is taken to be constant and equal to the planetary radius—is adequate for and will be made in the following considerations of the tropospheric eddy transport of angular momentum (although the zonal flow can extend deeply; see section 4 ). Meridional eddy transport of angular momentum is evidence of meridional eddy propagation and irreversible dynamics (e.g., Edmon et al. 1980 ). In a thin shell, eddies that propagate meridionally transport angular momentum in the

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Corentin Herbert, Rodrigo Caballero, and Freddy Bouchet

governed by the Hadley cell if we keep r constant by decreasing simultaneously the radiative cooling time τ (one could equivalently decrease the layer thickness at the equator h 0eq ). We list in Table 2 estimates of parameter values for different planetary atmospheres, which indicate that the bistability regime governed by the wave–jet feedback seems relevant in most cases of interest, although perhaps marginally for Earthlike planets. However, this conclusion hinges crucially on the friction

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