Fig. 1

Fields of view (FoVs) of the polar cap SuperDARN radars in the a Northern and b Southern hemispheres selected for the analysis. Specific beams (see Table 1) and gates (10–30) are shown by the colored boxes. The coloring is as follows: green—Inuvik (INV), blue—Rankin Inlet (RKN), red—Clyde River (CLY), brown—South Pole (SPS), light blue—Dome-C East (DCE), and orange—McMurdo (MCM). The solid gray lines are contours of constant magnetic latitude of 75° and 85°. The circle in a is the approximate location of a region where the plasma flow velocity magnitude was estimated while in b is simply an area of radar observations overlap