When the underwater volcano Hunga Tonga-Hunga Ha'apai, erupted on January 15, 2022, a plume of volcanic ash shot 58 kilometers (36 miles) into the air. New Zealand's National Institute of Water and Atmospheric Research (NIWA) set out on a month-long expedition to map the sea floor around the volcano and find out what caused it to erupt so violently.
When the underwater volcano Hunga Tonga-Hunga Ha'apai, erupted on January 15, 2022, a plume of volcanic ash shot 58 kilometers (36 miles) into the air. New Zealand's National Institute of Water and Atmospheric Research (NIWA) set out on a month-long expedition to map the sea floor around the volcano and find out what caused it to erupt so violently.
Joshua Stevens/NASA Earth Observatory
This satellite image shows the volcano on December 12, 2021, before the eruption. It's made up of two islands — Hunga Tonga and Hunga Ha'apai, which were joined by volcanic activity in 2015, giving the volcano its name.
This satellite image shows the volcano on December 12, 2021, before the eruption. It's made up of two islands — Hunga Tonga and Hunga Ha'apai, which were joined by volcanic activity in 2015, giving the volcano its name.
Maxar/Getty Images
This satellite image shows the volcano on January 17, 2022, after the eruption. The caldera, which was previously around 100 meters above sea level, has disappeared back under the water — once again separating the two islands.
This satellite image shows the volcano on January 17, 2022, after the eruption. The caldera, which was previously around 100 meters above sea level, has disappeared back under the water — once again separating the two islands.
Maxar/Getty Images
The RV Tangaroa, NIWA's research vessel, set sail in April 2022 to map the seafloor. Here, it is flanked by Hunga Ha'apai on the left, and Hunga Tonga on the right — the space in between is where the volcano caldera used to be.
The RV Tangaroa, NIWA's research vessel, set sail in April 2022 to map the seafloor. Here, it is flanked by Hunga Ha'apai on the left, and Hunga Tonga on the right — the space in between is where the volcano caldera used to be.
NIWA-Nippon Foundation TESMaP / Rebekah Parsons-King
Erica Spain, a marine geology technician with NIWA, was a member of the expedition whose work included sampling sediment from the seafloor. By analyzing rocks and mud, researchers can gain insight into how underwater ecosystems were impacted and are recovering.
Erica Spain, a marine geology technician with NIWA, was a member of the expedition whose work included sampling sediment from the seafloor. By analyzing rocks and mud, researchers can gain insight into how underwater ecosystems were impacted and are recovering.
NIWA-Nippon Foundation TESMaP / Rebekah Parsons-King
Spain also operated the multibeam, which maps the seafloor in 3D by sending out acoustic pulses.
Spain also operated the multibeam, which maps the seafloor in 3D by sending out acoustic pulses.
NIWA-Nippon Foundation TESMaP / Rebekah Parsons-King
Researchers taking samples of the sediment from the seafloor.
Researchers taking samples of the sediment from the seafloor.
NIWA-Nippon Foundation TESMaP / Rebekah Parsons-King
The RV Tangaroa has state-of-the-art equipment to help it uncover the mysteries of the seafloor. A remote underwater glider was used to gather data from the water surrounding the volcano.
The RV Tangaroa has state-of-the-art equipment to help it uncover the mysteries of the seafloor. A remote underwater glider was used to gather data from the water surrounding the volcano.
NIWA-Nippon Foundation TESMaP / Rebekah Parsons-King
The expedition also used a deep towed imaging system (DTIS) to get a better picture of what was going on under the water. On this seamount 80 kilometers from the volcano, the underwater camera filmed a school of tropical fish.
The expedition also used a deep towed imaging system (DTIS) to get a better picture of what was going on under the water. On this seamount 80 kilometers from the volcano, the underwater camera filmed a school of tropical fish.
NIWA-Nippon Foundation TESMaP / Rebekah Parsons-King