Finnish Meteorological Institute, Helsinki, Finland

The current distribution in the nightside magnetosphere during a substorm event on Dec. 10, 1996, is modeled using a local magnetic field model and two empirical large-scale magnetic field models. The empirical models utilizing both high-altitude spacecraft data and low-altitude energetic particle measurements suggest that a thin current sheet, which formed during the substorm growth phase extended from the inner magnetotail at least out to 20-30 R_E. It is shown that the results from the three different modeling approaches are consistent with each other, which is an important test for the validity of the empirical modeling methods. The models are compared and contrasted and their validity and use in magnetospheric studies are addressed.

in Magnetospheric Currents, AGU Monograph 118, eds. S. Ohtani and R. Fujii, pg. 81, Washington, D. C., 2000