Comparison of local energy conversion estimates from Cluster with global MHD simulations

Abstract

The local energy conversion across the magnetopause has been estimated with Cluster for two magnetopause crossings. A load region, conversion from magnetic to particle energy, was identified on the dayside high-latitude magnetopause during south/dawnward IMF. Another crossing of the dawn flank magnetotail during dominantly duskward IMF was identified as a generator region where the magnetosphere is loaded with magnetic energy. The observations have been compared to results of the BATS-R-US global MHD simulation based on observed IMF conditions. BATS-R-US reproduced the magnetopause regions crossed by Cluster as a load and a generator region, correspondingly. The magnitude of the estimated energy conversion from Cluster and the model are in quite good agreement. BATS-R-US cannot reproduce the observed sharp magnetopause and some topological differences between the observations and the model occur.