Altitude Dependence of Neutral Density Geomagnetic Storm Response

New formulations for satellite neutral density response to geomagnetic activity developed for the Jacchia-Bowman 2008 empirical model were based on data at GRACE altitudes and are applicable for large geomagnetic storms (ap>75). Storm response from the Jacchia-Bowman 2008 and NRLMSIS empirical models are tested at low satellite altitudes using a unique historic set of accelerometer neutral density data from satellites flown in 1982-1983 with perigee altitudes near 170 km. These data are particularly important for evaluating the capability of modern empirical and first principles models to predict satellite drag affecting reentry. The model validations are compared with those of selected CHAMP and GRACE data, 2002-2005, for similar conditions of geomagnetic activity, solar flux, local time and day of year to validate the altitude dependence of geomagnetic heating. Results are interpreted in the framework of General Circulation Models. To further understand thermospheric responses to solar wind energy deposition, we estimate the energy input required to produce these neutral density enhancements.