Global stormtime evolution of thermospheric zonal winds near dawn and dusk

Thermospheric neutral winds present a highly dynamic behavior with changing geophysical conditions. Geomagnetic storms are global events that affect the entire wind system, so it is important to understand the variability they generate in the winds and the temporal evolution of these variations. The Gravity field and steady-state Ocean Circulation Explorer (GOCE) mission provided dawn and dusk cross-track (zonal) neutral winds at an altitude of approximately 260 km. GOCE measurements from low and mid-latitudes were used to study the mean response of thermospheric neutral winds before, during and after a geomagnetic storm. A superposed epoch analysis was applied to normalized disturbance winds calculated from the GOCE zonal wind observations during 19 geomagnetic storms. The mean response of the zonal winds as a function of latitude and stormtime was calculated separately for the dawn and dusk sectors. The obtained mean stormtime response of the zonal winds at the different latitude regions and local time sectors will be compared and contrasted.