Rapid Characterization of Large Volcanic Eruptions: Measuring the Impulse of the Hunga Tonga Ha'apai Explosion From Teleseismic Waves

Most of the largest volcanic activity in the world occurs in remote places such as deep oceans or poorly monitored oceanic island arcs. 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 present a method to rapidly identify large volcanic explosions, based on analysis of seismic data. With this methodology, we promptly detect the 15 January 2022 Hunga Tonga Ha'apai eruption. We then analyze the seismic waves generated by the volcanic explosion and estimate its important first-order parameters. We further relate the parameters with the volcanic explosivity index (VEI). Our estimate of VEI ∼ 6 indicates that how the Hunga Tonga eruption is among the largest volcanic activity ever recorded with modern geophysical instrumentation and can provide new insights into the physics of large eruptions.