AN OVERVIEW OF THE IMPACT OF THE JANUARY 10-11, 1997 MAGNETIC CLOUD ON THE MAGNETOSPHERE VIA GLOBAL MHD SIMULATION

The results of a 3D MHD simulation of the January 10-11, 1997 geomagne tic storm are presented. The simulation results agree well with ground -based and geosynchronous observations. The 28 hours modeled by the si mulation include the magnetic cloud responsible for the storm, the sho ck preceding the cloud, and the dense plasma filament following it. Th e simulation shows that during the period of southward IMF ionospheric activity was strongly correlated to the solar wind density. The arriv al of the plasma filament during northward IMF pushed the dayside magn etopause well within geosynchronous orbit, but generated little ionosp heric activity. It appears that n(sw) as well as the orientation of B- sw plays a role in controlling the intensity of ionospheric and magnet ospheric activity.