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Abstract: We used Poynting fluxes and densities to investigate the stormtime thermosphere on November 10, 2004. Thermospheric energy, E th which is derived from , consists of two sources, solar ultraviolet radiation (E th UV) and the solar wind (E th SW). Responses of E th SW to interplanetary driving suggest that the thermosphere can be described by the equation dE th SW/dt=αε VS−(E th SW/τ), where ε VS represents the electric field; α and τ are constants. We show that: (1) E th SW is three times the ring-current energy; (2) αε VS is comparable with model predictions; (3) signatures of equatorward propagating disturbances were detected in neutral density profiles. [Copyright &y& Elsevier]

Abstract: Recent measurements by the Solar EUV (Extreme Ultra Violet) Experiment (SEE) aboard the Thermosphere–Ionosphere–Mesosphere Energetics and Dynamics satellite (TIMED) provide solar EUV spectral irradiance with adequate spectral and temporal resolution, and thus the opportunity to use solar measurements directly in upper atmospheric general circulation models. Thermospheric neutral density is simulated with the NCAR Thermosphere–Ionosphere–Electrodynamic General Circulation Model (TIEGCM) using TIMED/SEE measurements and using the EUVAC solar proxy model. Neutral density is also calculated using the NRLMSISE-00 empirical model. These modeled densities are then compared to density measurements derived from satellite drag data. It is found that using measured solar irradiance in the general circulation model can improve density calculations compared to using the solar proxy model. It is also found that the general circulation model can improve upon the empirical model in simulating geomagnetic storm effects and the solar cycle variation of neutral density. [Copyright &y& Elsevier]