Polar Thermosphere Zonal Wind Variations During Sudden Stratospheric Warmings

This study investigates the variability of zonal wind amplitudes in the quiet-time thermosphere at high latitudes during winter months, focusing on sudden stratosphere warming (SSW) events. Both observational and modeling databases are employed for this analysis. Notably, during SSW events, observations reveal a doubling of zonal wind amplitudes during nighttime across the lower-to-upper thermosphere, specifically at altitudes of 120km and 250km.

By conducting tidal wave diagnostics of zonal winds, the study establishes a link between thermospheric zonal wind variability and semidiurnal tides originating in the lower atmosphere, particularly within the altitude range of 90-300km following the onset of SSW events. These findings are significant as they shed light on the previously unrecognized role of tides in high latitude thermospheric dynamics.