Structure of the terdiurnal tide at 95 km

Satellite wind observations from the High Resolution Doppler Interferometer (HRDI) instrument on;;the Upper Atmosphere Research Satellite (UARS) are u sed to describe the latitudinal structure and seasonal variation of the ter diurnal (8 hour) atmospheric tide at 95 km. The amplitude of the annual ave rage tide is 5 m/s (meridional) and 15 m/s (zonal). Within the range observ ed (60 degrees S to 60 degrees N), the maximum amplitudes are found during fall and winter at midlatitudes. Only weak temporal correlations with the d iurnal and semidiurnal tides are seen on the monthly time scales resolved.