This proposal will validate the NCAR thermosphere/ionosphere/electrodynamic general circulation model (TIEGCM) for a variety of geophysical conditions, including winter solar minimum, summer solar maximum, and equinox for both solar minimum and maximum, by extensive comparison of the model predictions with all available observations and with predictions from empirical models. The PIs will emphasize the predicted thermosphere/ionosphere coupling, particularly the representation of the atmospheric dynamo. Results of this study will (1) demonstrate quantitatively the model improvement over previous model versions, especially the TIGCM; (2) establish the geophysical conditions for which the TIEGCM provides a good representation of the thermosphere/ionosphere system; and (3) identify areas for further model improvements, such as the representation of the equatorial ionosphere.***
