Post Tonga Eruption Survey

Jun 17

NIWA’s video - Tonga Volcano: Shot Gun Blast from the Deep

The Hunga-Tonga Hunga-Ha'apai volcano eruption generated the biggest atmospheric explosion recorded on Earth in more than 100 years. Funded by The Nippon Foundation, NIWA and SEA-KIT surveyed over 22,000km2 surrounding the volcano, including mapping 14,000km2 of previously unmapped seafloor as part of The Nippon Foundation GEBCO Seabed 2030 project. In April 2022 NIWA’s RV Tangaroa began a survey around the volcano’s caldera. This was followed by further investigation across the caldera by the SEAKIT Uncrewed Surface Vessel (USV).

My Role

I prepared and deployed NIWA’s glider Betty at the field site equipped with various sensors including a LISST on loan from Rutgers to measure water column particulates. I also collected water samples with the CTD rosette to determine the ocean’s physical properties and what the particulates were. These have been processed by Grace Frontin-Rollet and a glass layer was identified, which we attribute to the eruption.

During the voyage I also assisted with multi-coring and mapping of the Hunga-Tonga Hunga-Ha'apai caldera and surrounding area.

For the follow-up USV survey, I provided a RBR concerto CTD for the vehicle’s payload. I trained the SEAKIT technicians on the maintenance and operation of the instrument, and provided technical support during the USV deployment.

Outputs

Voyage report: https://niwa.co.nz/sites/niwa.co.nz/files/TAN2206-Voyage-Report.pdf