SM041-0030
The effect of subauroral polarization streams (SAPS) on the global thermosphere and ionosphere during geomagnetic storms

Tuesday, 15 December 2020
Poster
Wenbin Wang, High Altitude Observatory, Boulder, CO, United States, Dong Lin, Virginia Polytechnic Institute and State University, Blacksburg, VA, United States, Shanshan Bao, Rice University, Physics and Astronomy, Houston, TX, United States, Alan Geoffrey Burns, NCAR, HAO, Boulder, CO, United States, Jeffrey Garretson, Applied Physics Laboratory Johns Hopkins, Laurel, United States, John Lyon, Dartmouth College, Hanover, NH, United States, Viacheslav G Merkin, The Johns Hopkins University, Laurel, MD, United States, Adam T. Michael, Applied Physics Laboratory, Laurel, United States, Kevin H Pham, NCAR, Boulder, CO, CO, United States, Kareem Sorathia, Johns Hopkins University Applied Physics Laboratory, Laurel, MD, United States and Frank Toffoletto, Rice University, Department of Physics and Astronomy, Houston, TX, United States
Abstract:
Subauroral polarization streams (SAPS) are strong westward plasma drifts occurring in the afternoon to pre-midnight sector equatorward of auroral electron precipitation. In this study, we employ the high-resolution Multiscale Atmosphere-Geospace Environment (MAGE) model that was developed by the NASA DRIVE Science Center for Geospace Storms (CGS) to simulate SAPS and their effects on the global Thermosphere-Ionosphere system. The current implementation of the MAGE model two-way couples a global magnetospheric MHD code (GAMERA), a ring current model (RCM), and a global T-I model (TIEGCM). The model calculates mono-energetic electron precipitation from the MHD parameters, and diffuse electron precipitation from the RCM; both are essential for simulating SAPS realistically. For the 17 March 2013 storm event, the model simulated ion drifts in the SAPS channel and auroral electron precipitation that are in good agreement with data from three DMSP satellites, F16, F17, and F18. By comparing these observations with the model results from another MAGE run, in which the ion drifts in the SAPS channel in the TIEGCM are set to non-SAPS values, we find that there are large changes in both neutral winds and temperature when SAPS are included in the simulation. These changes are not limited only to the SAPS region: they are global. Associated with these global wind and temperature changes, there are the large differences in the simulated neutral composition and ionospheric F-region electron densities between the two model runs. We thus demonstrate clearly that SAPS, which is a localized mesoscale structure, can have significant, global effects on the coupled T-I system as a result of global ion-neutral dynamic coupling.
<< Previous Abstract | Next Abstract >>