Fig. 27From: Review of the accomplishments of mid-latitude Super Dual Auroral Radar Network (SuperDARN) HF radarsa Model ray paths of HF radar propagation through an ionosphere modulated by a TID. Focusing and defocusing at the ground is caused by the uneven contours of electron density (adapted from Samson et al. (1990)). b Example of FIR radar ground scatter data received along a single beam, versus ground range and universal time, showing several signatures of TID moving toward the radar. Reproduced from Fig. 2 of Grocott et al. (2013)Back to article page