Thermosphere and ionosphere dynamics during 20-30 March 1979 time period: Comparison of TIGCM calculated densities with observations

The Thermosphere Ionosphere General Circulation Model developed at the National Center for Atmospheric Research, (NCAR TIGCM), has been used to simulate the time-dependent variations of global thermosphere and ionosphere structure and dynamics during the 20-30 March 1979 time period. Thermospheric density variations predicted by the TIGCM during this period are statistically compared to satellite electrostatic triaxial accelerometer neutral density measurements obtained between 170 and 240 km altitude and to predictions made by the Mass Spectrometer Incoherent Scatter empirical model (MSIS-86). In its present state of development, the TIGCM has attained about the same accuracy (standard deviation), as MSIS-86. Incorporation of improved representation of ion drag, resulting from the downward flow of magnetospheric plasma on the nightside, has contributed to the TIGCM model accuracy.