Perturbations of O(~1D) VER, Temperature, Winds, Atomic Oxygen, and TEC at High Southern Latitudes

摘要

The study investigates previously unrecognized wind reversals of the daytime thermosphere in the Southern Hemisphere at latitudes of 50°S-70°S employing observations of O(~1D) airglow volume emission rates (VER), temperature, and neutral winds at 170-300-km height by the Wind Imaging Interferometer. Atomic oxygen densities derived from the Wind Imaging Interferometer O+ (732-733 nm) emission observations were also considered together with contemporaneous observations of total electron content by the TOPEX Poseidon satellite mission. The O(~1D) VER for fall equinox (March/April 1994) and summer solstice (January 1995) revealed a peak in the VER over the longitude range of 50°E-150°E, for both seasons and daytime local times. The Doppler temperatures also exhibited a maximum at the same location and times. The co-located zonal wind field shows a westward trough at 50°E-150°E with wind speeds reaching -450 m/s and an eastward peak at 200°E-300°E. Meridional winds show a "peak and trough" structure over the 50°E-150°E region, with a distinct eastern boundary at ~150°E. During summer solstice the atomic oxygen is depleted at the region of the O(~1D) VER enhancement in the presence of westward zonal wind. However, the total electron content observations showed a peak that coincided with the O(~1D) VER and temperature enhancements.