GW in airglow images at 630 nm caused by the tsunami from the Tohoku earthquake. Example of 630.0 nm images processed using length-8 FIR filters with passbands of (left) 0.3 to 1.7 mHz, (middle) 0.3 to 1.0 mHz to highlight the 26.2-min period waves, and (right) 1.0 to 1.7 mHz to highlight the 14.2-min period waves. The red line in each image indicates the tsunami location at the time of the image. The green line in the left panel indicates a path perpendicular to the airglow wave fronts. Adapted with permission from Makela et al. (2011). See also the movie in the electronic supplement to Makela et al. (2011).