Analytically-Based Rapid Modeling of Global Traveling Acoustic-Gravity Waves Generated by the 2022 Hunga-Tonga Volcanic Eruption

We develop an efficient and accurate simulation method for low-frequency acoustic-gravity waves (AGW) in a spherically layered atmosphere, modeling global wave propagation from the 2022 Hunga Tonga-Hunga Ha'apai eruption. Our approach uses an analytical solution to AGW equations under a one-dimensional atmospheric structure, reducing computational cost while maintaining key physical features. Simulations align closely with Himawari-8 satellite observations and ground-based barometric data, showing phase velocities of the Lamb wave pseudomodes match observations within 2.5% error. The simulation results also show that the (Formula presented.) pseudomode of Lamb waves (also referred to as the Pekeris mode) dominates above an altitude of 46 km, with its propagation speed being nearly unaffected by surface temperature conditions. The method efficiently handles large-scale simulations in minutes on standard servers, validating its reliability for studying AGWs.