Fig. 4From: Determining polar ionospheric electrojet currents from Swarm satellite constellation magnetic dataTemporal development of the sheet current densities measured from satellite Alpha as a function of QD latitude and time (bottom two panels) along with the corresponding Kp and AE index values (top panel). The middle panel shows the temporal development for the Northern Hemisphere, while the bottom panel shows the temporal development for the Southern Hemisphere. The results are given for the period 8 to 31 March 2015 for satellite Alpha. A positive current is defined in the sunward directionBack to article page