Speaker: Dr. Julien Thurin (University of Alaska, Fairbanks)
Abstract: The 2022 January 15 submarine eruption that occurred on the island of Hunga Tonga–Hunga Ha’apai has an unmatched significance in the modern era due to the extreme physical processes that unfolded during its catastrophic phase. These included a towering plume culminating at over 50 km in the atmosphere, a global tsunami carried by atmosphere-ocean interactions, a global atmospheric excitation that circled the globe several times, and one of the loudest sounds ever recorded. The eruption also generated enigmatic seismic signals that pose numerous challenges for modeling and interpretation. Leveraging global seismologic data allowed us to infer that a sequence of four repeated explosive-like moment tensors or downward point-force sources could adequately explain the most violent portion of the eruption.