Anatomy of the tsunami and Lamb waves-induced ionospheric signatures
generated by the 2022 Hunga Tonga volcanic eruption
Abstract
As tsunamis propagate across open oceans, they remain largely unseen due
to the lack of adequate sensors, hence limiting the scope of existing
tsunami warnings. A potential alternative method relies on the Global
Navigation Satellites Systems to monitor the ionosphere for Traveling
Ionospheric Disturbances created by tsunami-induced internal gravity
waves (IGWs). The approach has been applied to tsunamis generated by
earthquakes but rarely by undersea volcanic eruptions injecting energy
into both the ocean and the atmosphere. The large 2022 Hunga Tonga-Hunga
Ha’apai volcanic eruption tsunami is thus a challenge for tsunami
ionospheric imprint detection. Here, we show that in near-field regions
(<1500km), despite the complex wavefield, we can isolate the
tsunami imprint. We also highlight that the eruption-generated Lamb
wave’s ionospheric imprints show an arrival time and an amplitude
spatial pattern consistent with internal gravity wave origin.