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Abstract

Rapid and accurate estimate of the energy release of violent volcanic eruptions is crucial for unraveling possible cascading effects and mitigating associated destructive events. However, present methodologies often rely on empirical relations between eruption yield and waveforms, failing to incorporate full-waveform data due to the absence of appropriate synthetic tools. Here, we propose a fast computation approach, extended from normal-mode theory in seismology, to simulate atmospheric acoustic-gravity waves (AGWs) in a spherical model. We systematically analyze the dispersion properties of these waves with simulated results and validate our approach by comparing it with predictions in plane-earth models. Applying synthetic waveforms to the 15 January 2022, Hunga Tonga–Hunga Ha'apai eruption, we obtain an apparent explosive source at 18 km in the air with equivalent yield of ∼9EJ. This unexpected high altitude of the explosion centroid may be related to the volcanic plume traversing the stratosphere and reaching the mesosphere.