Seismological characterization of dynamics parameter of the Hunga Tonga explosion from teleseismic waves

Most of the largest volcanic activity in the world occurs in remote places as deep oceans or poorly monitored oceanic islands. Thus, our capacity of monitoring volcanoes is limited to remote sensing and global geophysical observations. However, the rapid estimation of volcanic eruption parameters is needed for scientific understanding of the eruptive process and rapid hazard estimation. We first a method to rapidly identify large volcanic explosions, based on analysis of seismic data. The method automatically detects and locate long period (0.01-0.03Hz) signals associated with physical processes close to the Earth surface, by analyzing surface waves recorded at global seismic stations. With this methodology, we promptly detect the January 15, 2022 Hunga Tonga eruption, among many other signals associated with known and unknown processes. We further use the waves generate by the Hunga Tonga volcanic explosion and estimate important first-order parameters of the eruption (Force spectrum, impulse). We then relate the estimated parameters with the volcanic explosivity index (VEI). Our estimate of VEI~6, indicate how the Hunga Tonga eruption is among the largest volcanic activity ever recorded with modern geophysical instrumentation, and can provide new insights about the physics of large volcanoes.