Ionospheric Disturbances after the 2022 Hunga Tonga-Hunga Ha’apai Eruption above Indonesia from GNSS-TEC Observations

Abstract

On 15 January 2022, a VEI 5 eruption occurred at the submarine Hunga Tonga-Hunga Ha’apai (HTHH) Volcano in the Southwest Pacific, causing an ash plume reaching a height of 50–55 km. The eruption generated strong acoustic-gravity waves in the near-field and stations all over the world recorded Lamb waves (LW) that travelled around the earth multiple times at a speed of ~0.3 km/s. Here we report ionospheric anomalies due to the LW over Indonesian islands, 5000–10,000 km away from the volcano, in terms of changes in total electron contents (TEC) using the nationwide network of GNSS stations. We detected ionospheric anomalies travelling above Indonesia several times both westward and eastward. The first passage of LW over Java caused strong TEC increases of >12 TECU. The wave circled the earth and returned to Java on subsequent days. The second passage was recorded early 1/17, the anomaly decayed to 6 TECU. We also detected the passage of long-path waves propagating from west to east. In addition to such anomalies, we examined the existence of ionospheric disturbances apparently propagating from the geomagnetic conjugate point of the volcano that could possibly emerge in Indonesia. However, their signatures in Indonesia were not clear.

Diverse Ionospheric Disturbances by the 2022 Hunga Tonga‐Hunga Ha'apai Eruption Observed by a Dense GNSS Array in New Zealand

“…Here we demonstrate that the SIPs of satellite‐station pairs concentrate most tightly by assuming the height of ∼300 km (Figure 9). We also constrained the height of the ionospheric disturbance due to the 2022 HTHH eruption in Indonesia (Muafiry et al., 2022), and the result (Figure S2 in Supporting Information ) showed a good agreement with the New Zealand case.…”

“…In the simulation by Kherani et al (2016), they call it co-tsunami ionospheric disturbances (CTID), although it was LW in the present case rather than propagating tsunamis that excited them. According to earlier reports, the ionospheric signatures of the LW traveling round the earth several times were observed in Japan (Heki, 2022), Indonesia (Muafiry et al, 2022), and in China (Li et al, 2023). Here we look for those signals in New Zealand.…”

“…According to earlier reports, the ionospheric signatures of the LW traveling round the earth several times were observed in Japan (Heki, 2022), Indonesia (Muafiry et al., 2022), and in China (Li et al., 2023). Here we look for those signals in New Zealand.…”

“…Themens et al (2022) analyzed global GNSS-TEC data and found ionospheric responses to the passage of the Lamb Wave (LW) propagating worldwide along the surface by ∼0.3 km/s. Regional GNSS-TEC observations detected multiple passages of LW in Japan (Heki, 2022), China (Li et al, 2023, and in Indonesia (Muafiry et al, 2022). Conjugate ionospheric anomalies were found to propagate in two hemispheres simultaneously by Themens et al (2022) and were further studied by Lin et al (2022).…”

Ionospheric Disturbances Over Primorsky Krai Caused by the Eruption of the Hunga Tonga-Hunga Ha’apai Volcano on January 15, 2022

“…Цунами, землетрясения и извержения вулканов способны инициировать возмущения в различных средах: атмосфере, литосфере и гидросфере [Astafyeva, 2019]. В ионосфере такие возмущения могут распространяться на большие расстояния [Astafyeva, Afraimovich, 2006;Chum et al, 2012;Muafiry et al, 2022;Verhulst et al, 2022;Wright et al, 2022].…”