Fig. 1From: The dynamics of geomagnetic substorms with the WINDMI modelWINDMI under 191-kV input. The WINDMI model is driven with a synthetic southward IMF voltage signal with the solar wind velocity Vx being 450 km/s and IMF Bz of − 6.67 nT. A substorm is produced when sufficient energy is stored in the magnetotail and a critical current \(I_c\) is reachedBack to article page