Evolution of the Birkeland Currents During the Whole Heliosphere Interval from Various Simulations

This study examines the magnitude of the Birkeland currents in the magnetospheric system during whole heliosphere interval (WHI) from March 20-April 16, 2008 (Carrington Rotation 2068). We utilize results from standalone Lyon-Fedder-Mobarry (LFM) simulations and a coupled magnetosphere-ionosphere-thermosphere simulation (CMIT) for the duration of the WHI. The CMIT simulation uses a more sophisticated ionospheric model than that of the standalone LFM. An LFM simulation was also run with constant conductivity, and another was run in which the interplanetary magnetic field (IMF) was set to 0 nT. The run with the IMF turned off will tell us the amount of Birkeland currents that are produced by mechanical interactions.