Storm time meridional wind perturbations in the equatorial upper thermosphere

Abstract

We present observations from the Coupled Ion Neutral Dynamics Investigation (CINDI) of storm time meridional winds in the neutral atmosphere near the magnetic equator at 400 km altitude. Observations near the magnetic equator in the southern geographic hemisphere are dominated by energy inputs from the southern Polar Regions that produce south to north (equatorward) wind perturbations to accompany perturbations in the neutral density and temperature. In one exceptional case, when observations are made near midnight and the north magnetic pole rotates through the midnight sector, north to south (poleward) meridional wind perturbations are observed just south of the magnetic equator. Accompanying perturbations in the neutral density on the dayside and the nightside are consistent with observed increases in the ion temperature and inferred increases in the neutral temperature in accord with hydrostatic equilibrium. Key Points Equatorward winds during geomagnetic storms.Neutral density and temperature enhancements during storms.Add to and compare with previous work. ©2013. American Geophysical Union. All Rights Reserved.