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G. Schubert (Space Science Applications Lab., The Aerospace Corporation and Dept. of Earth & Space Sciences, IGPP, UCLA), M. P. Hickey (Clemson Univ.), R. L. Walterscheid (Space Sciences Applications Lab., The Aerospace Corporation)
Thunderstorms in Jupiter's atmosphere are likely to be prodigious generators of acoustic waves, as are thunderstorms in Earth's atmosphere. Accordingly, we have used a numerical model to study the dissipation in Jupiter's thermosphere of upward propagating acoustic waves. Model simulations are performed for a range of wave periods and horizontal wavelengths believed to characterize these acoustic waves. The possibility that the waves observed by the Galileo probe might be acoustic waves is also investigated. Whereas dissipating gravity waves can cool the upper atmosphere through the effects of sensible heat flux divergence, it is found that acoustic waves mainly heat the thermosphere by viscous dissipation. Though the amplitudes and mechanical energy fluxes of acoustic waves in Jupiter's atmosphere are poorly constrained, the calculations suggest that dissipating acoustic waves can locally heat the thermosphere at a significant rate and thereby account for the high temperatures of Jupiter's upper atmosphere.
Supported by NASA Planetary Atmospheres Program.