Pacific

Two-year anniversary of Tonga's tsunami terror

11:10 am on 15 January 2024

The eruption of the Hunga-Tonga-Hunga-Haa'pai volcano in Tonga as photographed by NASA's NOAA GOES West satellite on 15 January 2022. Photo: AFP PHOTO / NASA / NOAA

Today marks the second anniversary of the Hunga Tonga-Hunga Ha'apai volcanic eruption which devastated the kingdom of Tonga.

The Hunga Tonga-Hunga Ha'apai eruption is the largest since the 1883 eruption of Krakatoa in Indonesia, and the largest ever recorded by modern instrumentation.

The violent force of the eruption triggered a tsunami that killed three people and left thousands homeless.

The tsunami waves devastated the small islands of 'Atata and Mango, forcing the communities on both islands to relocate to the main island, Tongatapu, and the third largest island, 'Eua.

The powerful explosion caused a communications blackout that left the kingdom without internet and no international phone service.

The effects of the January 15, 2022 eruption continue to impact the kingdom.

Last October, power outages experienced in Tongatapu were a result of corrosion caused by the ash that had solidified on electrical cables.

One of a kind eruption

Taaniela Kula Photo: RNZ Pacific/Moera Tuilaepa-Taylor

Head of Tonga's Geological Service Taaniela Kula told RNZ Pacific the Hunga Tonga-Hunga Ha'apai volcanic eruption is a one-of-a-kind.

"It's the first of its kind to be recognised by the volcanology community - confirming that it's a new kind of volcano eruption."

He said no one in the volcanology community had witnessed or had ever heard of such an eruption, blowing up from the seafloor and going beyond the atmosphere into the mesosphere, 58km above sea level.

"Most of the volcanology community and the science community were very interested in finding out what was the true cause, and the mechanism that created this enormous eruption, that was heard around the world four times," he said.

Research into the eruption

The 2022 eruption shot out an unprecedented amount of water vapour into the sky.

The vapour reached heights of up to 55 kilometres and depleted 5 percent of the ozone layer over the tropical south-western Pacific and Indian Ocean regions in one week.

Tonga's underwater volcano disaster triggered waves up to 90 metres high according to a study involving a collaboration of scientists from numerous agencies including NASA, NIWA, and the Tonga Geological Service.

The University of Miami and the Khaled bin Sultan Living Oceans Foundation report states the eruption of the Hunga Tonga-Hunga Ha'apai volcano in 2022 was more powerful than the largest US nuclear test.

A lot more scientific information has been published following the devastating Hunga Tonga-Hunga Ha'apai volcanic eruption.

The Hunga Tonga-Hunga Ha'apai crater and caldera before and after the eruption. Photo: Sung-Hyun Park/Korea Polar Research Institute, CC BY-SA

St Mary's Cathedral in Tonga at a commemoration service for the first anniversary of the devastating Hunga Tonga-Hunga Ha'apai volcanic eruption which took place on 15 January 2022. Photo: RNZ / Angus Dreaver

Damage after the eruption. Photo: Supplied by Dior Sheen

Footage taken by Japan's Himawari-8 satellite and released by Japan's National Institute of Information and Communications shows the eruption in 2022. Photo: AFP / National Institute of Information and Communications

Powerful undersea volcano eruption in Tonga. Photo: Tonga Geological Services/ EyePress News via AFP