Fig. 6From: Global and local Joule heating during substorms in St. Patrick’s Day 2015 geomagnetic stormTop to bottom: IMF Bz (in GSM coordinate) from WIND spacecraft and the local electrojet index (IL) derived from the IMAGE magnetometer network, during substorm event 17–18 March 2015. The duration of expansion phase of the substorm is marked with two vertical dashed linesBack to article page