The 15 January 2022 Hunga Tonga Eruption History as Inferred From Ionospheric Observations

On 15 January 2022, the Hunga Tonga-Hunga Ha'apai submarine volcano erupted violently and triggered a giant atmospheric shock wave and tsunami. The exact mechanism of this extraordinary eruptive event, its size and magnitude are not well understood yet. In this work, we analyze data from the nearest ground-based receivers of Global Navigation Satellite System to explore the ionospheric total electron content (TEC) response to this event. We show that the ionospheric response consists of a giant TEC increase followed by a strong long-lasting depletion. We observe that the explosive event of 15 January 2022 began at 04:05:54UT and consisted of at least five explosions. Based on the ionospheric TEC data, we estimate the energy released during the main major explosion to be between 9 and 37 Megatons in trinitrotoluene equivalent. This is the first detailed analysis of the eruption sequence scenario and the timeline from ionospheric TEC observations.

Automated summary

In this study, data from ground-based receivers of the Global Navigation Satellite System are analyzed to explore the ionospheric response to the eruption of the Hunga Tonga-Hunga Ha'apai submarine volcano. The ionospheric response is shown to consist of a significant increase in total electron content (TEC) followed by a strong and long-lasting depletion. The energy released during the main explosion is estimated based on the ionospheric TEC data.