The effects of gravity waves on (1) minor species in the presence of winds; (2) the temperature inversion layer in the presence of a critical layer.

摘要

That gravity waves play an important role on energy and momentum transport in the upper atmosphere has been known and recognized for quite some time. In part I, we wish to investigate temporal and spatial response of Ozone, Hydrogen, and OH emission profiles due to a gravity wave with horizontal winds included. The response of the minor species to a linear gravity wave in the presence of winds can be nonlinear if the density profile of the minor species has a layered structure. Chapman functions are used for the analytic models of the minor species profile. A perturbation expansion is developed which enables us to obtain high-order response of the minor species in the gravity wave velocity up to any desired order. We found that the shape of the minor species' profile would suffer a significant change in the presence of winds, while the high-order terms cannot be ignored if the minor species have a steep density gradient and the response is always greater below the peak than at or above the peak.; In part II, the effects of gravity waves on the temperature inversion layer in the presence of a critical layer have been studied. A sudden and dramatic mesospheric heating event was observed during the ALOHA-93 Campaign. The data showed a persistent, narrow temperature inversion layer near OH peak with a maximum temperature rise to 40 K. Based on our data analysis, the temperature-inversion layer could be associated with energy deposition from gravity wave-critical layer interaction.