Fig. 10From: New aspects of the upper atmospheric disturbances caused by the explosive eruption of the 2022 Hunga Tonga–Hunga Ha’apai volcanoRange-time plots of the northward plasma flow in the beam-6, 7, and 8 directions observed by the SuperDARN Hokkaido east radar (a, c, e). The color bar of each panel indicates the northward component of the line-of-site velocity in a range from − 150 to 150 m/s. Panels b, d, f show the time-series plots of the northward plasma flow at the range gate number of 17 in each beam. The horizontal red arrows in the panels b, d, f indicate the observed periods of 4-min oscillations. The phase variation of the 4-min oscillations for the range gate number is shown in the dashed blue arrowsBack to article page