ENERGY RELEASED BY RECOMBINATION OF ATOMIC OXYGEN AND RELATED SPECIESAT MESOPAUSE HEIGHTS

This paper studies the total chemical energy release of seven exotherm ic reactions involving odd oxygen and odd hydrogen species at mesopaus e heights. Monthly and zonally averaged heating rates are calculated o n the basis of atomic oxygen and atomic hydrogen densities as inferred from the SME satellite measurements in the altitude regime from 80 to 93 km. Trace constituents not available from SME were determined by m eans of a photochemical model. The resulting heating rates are found t o be fairly high at all seasons, altitudes, and latitudes accessible t o SME satellite measurements. Very large heating rates occur at high l atitudes in early winter, reaching a maximum value of approximately 28 K per day. Consequently, chemical heating appears to play an importan t role in the energy budget and the dynamics of the upper mesosphere a nd lower thermosphere.