Meteotsunami waves induced by atmospheric pressure disturbances from volcanic eruptions

Meteotsunamis, which occur due to Proudman resonance during atmospheric disturbances, are a significant but often overlooked coastal hazard. This study utilizes Boussinesq-type wave equations to explore the influence of the Froude number (Fr) on meteotsunami development and peak wave heights. The findings highlight two distinct hydrodynamic regimes: under supercritical conditions (Fr≥1), locked waves dominate the maximum wave height (ηmax), while subcritical conditions (Fr<1) ηmax refer to the free-wave height. Notably, wave coupling persists throughout the transient phase until dynamic equilibrium is reached, with locked and free waves showing an inverse relationship in amplitude evolution—when one component amplifies in height, the other attenuates. A predictive formula for transient maximum wave height is derived and validated against numerical simulations. The model's predictive performance is further validated through an analysis of the 2022 Hunga Tonga-Hunga Ha'apai eruption. Simulated meteotsunami waveforms closely match corrected Deep-ocean Assessment and Reporting of Tsunamis (DART) buoy data across Pacific regions, and the predicted maximum wave height from the equation shows strong agreement with both the DART data and the simulated results.