Vertical motions in the thermosphere over Mawson, Antarctica

High time resolution measurements of Doppler shift and broadening of the QI 630 nm emission in the night airglow and aurora have provided determinations of vertical velocities and temperatures in the neutral thermosphere over Mawson, Antarctica. The vertical wind exhibits a large, rapid, and complex response to geomagnetic energy input. Upward winds greater than 50 m/s are frequently associated with the expansion phase of auroral substorms. Following the disturbance, prolonged periods of downward winds produce temperature enhancements of 200 K outside the source region, thus providing a mechanism for the redistribution of geomagnetic energy. Oscillatory behavior consistent with thermospheric gravity waves is observed during both quiet and disturbed conditions.