The 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 (
We provide evidence that midlatitude postsunrise traveling ionospheric disturbances (TIDs) are comprised of electrified waves with an eastward propagation component. The post‐sunrise gravity wave (GW) wind‐induced dynamo action effectively generated periodic meridional polarization electric fields (PEFs), facilitating TID zonal propagation in a similar fashion as GW‐driven neutral perturbations. A combination of near‐simultaneous eastward and upward observations using the Millstone Hill incoherent scatter radar along with 2‐dimensional total electron content maps allowed resolution of TID vertical and horizontal propagation as well as zonal ion drifts
- NSF-PAR ID:
- 10375350
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Geophysical Research Letters
- Volume:
- 48
- Issue:
- 18
- ISSN:
- 0094-8276
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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