KOPRI Maps 8.9 Cubic Kilometers of Seafloor Shift From 2022 Tonga Eruption
Updated
Updated · dongascience.com · Sep 14
KOPRI Maps 8.9 Cubic Kilometers of Seafloor Shift From 2022 Tonga Eruption
1 articles · Updated · dongascience.com · Sep 14
Summary
8.9 cubic kilometers of material were displaced across the seafloor during the January 2022 Tonga eruption, KOPRI said, enough to blanket Seoul under 15 meters of debris.
A roughly 5-km-wide submarine caldera collapsed by an average of about 1 km, and seismic data showed pyroclastic deposits up to 150 meters thick filling the basin.
The team said that sudden collapse likely amplified the tsunami, while sediment layers between and beneath the deposits indicate landslides unfolded at the same time as the eruption.
About 80 days after the blast, KOPRI diverted the icebreaker Araon from its Antarctic return voyage to survey Tonga; the Nature Geoscience study was published on Sept. 11.
The findings add to global efforts to explain an eruption that vaporized seawater equal to about 10% of stratospheric water vapor and sent ash into the mesosphere.
Could mapping the hidden scars of the Tonga collapse finally unlock the secret to predicting the deadliest volcanic tsunamis?
With most of the volcano's magma still lurking underwater, could another catastrophic, tsunami-triggering eruption strike without warning?
How did a relatively small underwater volcano manage to alter the stratosphere and sever global communications in a single blast?
The 8.9 km³ Collapse: Mapping, Impacts, and Global Lessons from the 2022 Hunga Tonga-Hunga Ha'apai Eruption
Overview
The Hunga Tonga-Hunga Ha'apai eruption on January 15, 2022, triggered a rapid, vertical collapse of the submarine caldera, displacing a huge volume of water and generating a massive tsunami. This event also severed Tonga’s only undersea cable, causing a communications blackout. The eruption produced powerful atmospheric Lamb waves that coupled with the ocean, creating fast-moving meteotsunamis that reached distant shores much faster and higher than forecast models predicted. Traditional tsunami warning systems failed to anticipate these effects, highlighting the urgent need for improved monitoring and real-time hazard assessment for submarine volcanic events.