Two-year anniversary of Tonga's tsunami terror

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

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.

Satellite image overview of the Hunga Tonga-Hunga Ha'apai volcano before the main eruption.
"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 55km and depleted 5% of the ozone layer over the tropical southwestern Pacific and Indian Ocean regions in one week.

Tonga's underwater volcano disaster triggered waves up to 90m 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.

- RNZI