Thin current sheet evolution as seen in observations, empirical models and MHD simulations

Abstract

The inner and midtail current sheet is examined during a substorm on Dec 10, 1996 using multispacecraft observations, empirical models, and global MHD simulations. Both the simulation and empirical magnetic field model show good agreement with observations, which substantially increases the confidence in both methods. Both locate the thin current sheet inner edge at ∼7 RE, and give a scale size of ∼15 RE in tailward and cross‐tail directions. The MHD simulation confirms the empirical model result that the thin current sheet remained stable after a local auroral breakup and indicates that the activity followed from flow channels generated at ∼40 RE independent of the thin current sheet evolution closer to the Earth.