Traveling Ionospheric Disturbances induced by the 2022 Hunga Tonga–Hunga Ha’apai Volcano Eruption: Observation and Simulation

The eruption of the Hunga Tonga-Hunga Ha’apai (HTHH) submarine volcano on January 15th, 2022, generated atmospheric pressure disturbances that propagated in Lamb waves, detected worldwide along with the associated oscillations. The perturbing atmospheric waves induce traveling atmospheric disturbances (TADs) near the Earth’s surface and traveling ionospheric disturbances (TIDs) in the upper atmosphere. In this study, the global propagation of TADs is demonstrated with the Himawari-8 satellite images. The Doppler sounding systems, ionosondes, and co-located ground-based barometers are used to observe TADs and TIDs over Japan and Taiwan. The horizontal velocities of TADs and TIDs are found to vary with altitude. To further investigate the observed TIDs' characteristics, numerical simulations are conducted with GITM-R, a three-dimensional non-hydrostatic model of the upper atmosphere equipped with a two-way coupling between the coarser grid layer and the locally refined layers. The study regions focus on the Tonga near field, Japan, and Taiwan. Finally, the numerical results are compared and discussed with the total electron content (TEC) data from ground-based Global Navigation Satellite System (GNSS) receivers in conjunction with the above observations.