A new coupled middle atmosphere and thermosphere general circulation model has been developed, and some first results are presented. An investigation into the effects of the diurnal tide upon the mean composition, dynamics and energetics was carried out for equinox conditions. Previous studies have shown that tides deplete mean atomic oxygen in the upper mesosphere-lower thermosphere due to an increased recombination in the tidal displaced air parcels. The model runs presented suggest that the mean residual circulation associated with the tidal dissipation also plays an important role. Stronger lower boundary tidal forcing was seen to increase the equatorial local diurnal maximum of atomic oxygen and the associated O(1S) 557.7 nm green line volume emission rates. The changes in the mean background temperature structure were found to correspond to changes in the mean circulation and exothermic chemical heating.
- Atmospheric composition and structure (middle atmosphere - composition and chemistry)
- Meterology and atmosphere dynamics (middle atmosphere dynami cs; waves and tides)
ASJC Scopus subject areas
- Astronomy and Astrophysics
- Atmospheric Science
- Earth and Planetary Sciences (miscellaneous)
- Space and Planetary Science