Fig. 2.From: Giant ionospheric disturbances observed with the SuperDARN Hokkaido HF radar and GPS network after the 2011 Tohoku earthquakeTime and ground range variations of (a) echo power and (b) Doppler velocity on beam 4. Data with echo power higher than 10 dB are displayed. Propagation velocity of each gravity wave shown in (a) is overlaid in (b). The themisscan starts at 1500:12 JST after the mainshock at 1446:23 JST.Back to article page