The 15 January 2022 Hunga Tonga eruption history as inferred from
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 (GNSS) 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 5 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 TNT
equivalent. This is the first detailed analysis of the eruption sequence
scenario and the timeline from ionospheric TEC observations.