Affiliation:
1. Space Weather Division National Institute for Space Research (INPE) São José dos Campos Brazil
2. Northwest Research Associates EUA Boulder CO USA
Abstract
AbstractThe biggest volcanic eruption since 1991 happened on 15 January 2022 on the island of Hunga Tonga‐Hunga Haʻapai (20.6°S; 175.4°W) in the South Pacific between 4:00 and 4:16 UT. The updrafts from the eruption reached 58 km height. In order to observe its ionospheric effects, approximately 750 GNSS receivers in New Zealand and Australia were used to calculate the detrended total electron content (dTEC). Traveling ionospheric disturbances (TIDs) were observed over New Zealand 1.0–1.5 hr after the volcano eruption, with a horizontal wavelength () of 1,525 km, horizontal phase velocity () of 635 m/s, period (τ) of 40 min, and azimuth (α) of 214°. On the other hand, TIDs were observed 2–3 hr after the eruption in Australia with , , τ, and α of 922 km, 375 m/s, 41 min, and 266°, respectively. Using reverse ray tracing, we found that these GWs originated at z > 100 km at a location ∼500 km south of Tonga, in agreement with model results for the location of a large amplitude body force created from the breaking of primary GWs from the eruption. Thus, we found that these fast GWs were secondary, not primary GWs from the Tonga eruption.
Funder
Fundação de Amparo à Pesquisa do Estado de São Paulo
Earth Sciences Division
National Science Foundation
Publisher
American Geophysical Union (AGU)
Subject
Space and Planetary Science,Geophysics