Fig. 16
From: Review of the accomplishments of mid-latitude Super Dual Auroral Radar Network (SuperDARN) HF radars
The occurrence rate (%) of ionospheric echoes from beam 4 of TIG detected during all seasons, and sorted according to geomagnetic activity Kp > 1 to 2; Kp > 3 to 4 and Kp > 5 to 6. Model auroral oval boundaries are superimposed for AL = − 64 nT (Kp = 2−), AL = − 240 nT (Kp = 4−), and AL = − 458 nT (Kp = 6−). Adapted from Fig. 5 of Parkinson et al. (2003b)