Observations and Simulations of Traveling Ionospheric Disturbances of the 15 January 2022 Tonga Volcano Eruption Observed in Taiwan and Japan

At 04:15 UT, intense eruptions of the Tonga volcano generated atmospheric shocks and pressure fluctuations, which induced traveling atmospheric disturbances (TADs) near the Earth’s surface, further went into the upper atmosphere and activated traveling ionospheric disturbances (TIDs) on 15 January 2022. Himawari-8 satellite images depict TADs propagating worldwide while ground-based barometers, Doppler sounding systems, and ionosondes observe TADs and TIDs in Taiwan and Japan. For the TADs, the horizontal speed of Himawari-8 is about 310 m/s, and that of the barometer networks is 275.5-296.5 m/s. Therefore, the TADs in the troposphere and stratosphere travel at sound speeds. For the TIDs, the horizontal speed observed by the ionosondes (Doppler sounding systems) is 232.8-568.6.5 m/s (186.0-459.5), respectively, which is rather complex. The ionosondes and Doppler data show that the TID can uplift the ionosphere as high as about 80-140 km. GITM‐R Simulations will be used to reproduce the observed TID features, which will be presented and discussed.