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Allison, M., 1992: Planetary atmospheres, dynamics. In The Astronomy and Astrophysics Encyclopedia. S.P. Maran, Ed. Van Norstrand Reinhold, pp. 510-514.
Planetary atmospheres are the circulating fluids of world-sized thermodynamic engines. Their observed wind and wave motions are the dynamic response to diffm:ntial heating imposed by thell absorbed solar radiation and, in the case of the giant outer planets, to the internal energy generated by their formative gravitational contraction. Although partly derived from the observational and analytical tools of astronomy, the comparative study of dynamic atmospheres has emerged as an extension of terrestrial meteorology to the rich vanety of size, rotation, mass, temperature, and composition exhibited by the other planets in the solar system. The subject has begun to mature only over the past two decades, largely as a result of the preliminary reconnaissance of the planets by spacecraft. Although based on well-understood laws of mechanics, thermodynamics, chemistry, and radiation, the aggregate behavior of these macroscopic systems has proven outstandingly difficult to deduce and predict. There is as yet no general theory of atmospheric dynamics that can comprehensively account for the observed features of extraterrestrial wind patterns. Some progress has been made, however, in diagnosing the basic physical balances and kinematics. Aside from the challenge to solve individual problems of fascinating complexity, the comparative investigation of motions in planetary atmospheres proceeds with the expectation of eventually attaining a fundamental improvement in the unified understanding of geophysical fluid dynamics.
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