Fig. 1From: Light ion dynamics in the topside ionosphere and plasmasphere during geomagnetic stormsa SLIDEM effective ion mass plot for a sample time period (Dst minimum on 1 Sept 2019), with the Dst index overplotted as a black curve; b shows the same but for the TBT-2015 model. Dayside is in the bottom half of the plot, nightside in the top half. Ascending MLT = 12.5, descending MLT = 0.5Back to article page