First Observations of Antarctic Mesospheric Tidal Wind Responses to Recurrent Geomagnetic Activity

摘要

We report an analysis of the response of tides in neutral atmospheric mesospheric winds to recurrent geomagnetic activity in 2005 over Antarctica. The mesospheric winds were observed by the Davis meteor and medium frequency radars (68.5 degrees S, 77.9 degrees E; magnetic latitude, 74.6 degrees S). The zonal component of the daily prevailing winds showed a westward increase as the geomagnetic activity increased, while the meridional prevailing winds did not show a clear response. The semidiurnal tides responded greatly to geomagnetic activity, with significant increases in amplitude. The zonal and meridional semidiurnal tides both showed a clear upward propagating phase but responded differently to geomagnetic activity. The amplitude of the meridional component of the diurnal tides increased significantly, while the zonal diurnal tidal amplitude showed no apparent change. These results indicate that geomagnetic activity can significantly influence mesospheric dynamics.

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