A Comparison of Cross-Track Ion Drift Measured by the Satellites and Plasma Convection Velocity Measured by SuperDARN

Cross-track ion drifts measured by the Swarm A satellite are compared with colocated line-of-sight Super Dual Auroral Radar Network (SuperDARN) velocities in approximately the same directions. More than 200 Swarm A passes over four polar cap SuperDARN radars in the Northern and Southern Hemispheres are considered. Overall, the Swarm-based velocities are larger than the SuperDARN velocities; the slope of the best fit line to the data is similar to 0.67. Somewhat stronger differences are found when Swarm A measurements for the entire year 2016 are compared with SuperDARN vector data from global-scale convection maps. Swarm ion drift data demonstrate known features of the high-latitude convection patterns, for example, reverse convection cells at interplanetary magnetic field B-z > 0. The latitudes of the convection reversal boundary inferred from SuperDARN are found to be in reasonable agreement with those determined from Swarm A and Swarm B, with Swarm-based latitudes occurring roughly 1 degrees more equatorward, typically.