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R. V. Yelle (Dept. of Physics \& Astronomy, Northern Arizona University), L. A. Young (Center for Space Physics, Boston University), R. E. Young (NASA Ames Research Center)
The temperature perturbations in the jovian thermosphere measured by the Atmospheric Structure Instrument (ASI) on the Galileo probe carry a significant amount of energy, if the perturbations are interpreted as upward propagating gravity waves. Young et al. (Science, vol 276, pp 108-111, 1997) found that the observed temperature perturbations could be matched by two waves, determined the wave amplitudes and constrained the altitude profile and phase speed for these waves. They argued that heating by the waves could explain the high thermospheric temperatures on Jupiter. Subsequently, Matcheva and Strobel (in press, Icarus), using a quasi-Boussenesq approximation in a 1-D atmosphere showed that, in addition to the energy deposited by the viscous dissipation of waves, the downward flux of sensible heat leads to increased heating at low altitudes and cooling at high altitudes. The thermospheric temperature calculated with this approach was found to be smaller than that observed for the nominal wave characteristics presented by Young et al. The mean temperature profile is determined by thermal conduction, the heating profile due to waves, and its relationship to the sources of radiative cooling in the atmosphere. In this paper we continue investigation of the thermal effects of the ASI waves by considering in more detail the viscous dissipation of upwardly propagating gravity waves using a rigorous expression for the wave heating rate and by including radiative cooling terms in the vicinity of the jovian mesopause.