Internal tsunami waves in a stratified ocean induced by explosive volcano eruption: A parametric source.

This article focuses on the theoretical analysis of internal waves generated during explosive eruptions of underwater volcanoes, motivated by observations from the 2022 Tonga Archipelago eruption. Using Le Méhaute's parametric model—originally developed for surface tsunami waves—the study models internal wave generation in a stratified ocean with constant buoyancy frequency, representing the wave field as a multimode train of internal waves. The results indicate that internal waves propagate slowly and persist near the source for extended periods, with different modes arriving at different times and interfering complexly, suggesting that internal wave measurements can help delineate underwater eruption sources. The study provides analytical formulas and computational results for wave amplitudes and propagation characteristics in both shallow and deep seas, emphasizing the potential of internal waves as indicators distinct from surface tsunamis.