Tonga Underwater Volcano Erupts, Triggers Tsunami Warnings In US, Australia, Japan, NZ

A massive underwater volcanic eruption off the island nation of Tonga has been felt across the south-western Pacific, with many tsunami warnings still in place, including for much of Australia’s east coast. The eruption has been touted by US Stormwatch as the most powerful eruption of the 21st Century with a blast radius of 260 kms. 

The Bureau of Meteorology said the Hunga Tonga-Hunga Ha’apai volcano erupted at 3.10pm AEDT on Saturday, and tsunami waves have been observed as a result of the eruption.

The volcano lies about 65 km north of Tonga’s capital city, Nuku’alofa. It was followed by a 1.2-metre tsunami observed at the capital Nuku’alofa about 20 minutes later, and skies filled with ash, steam and gas. In Fiji and Vanuatu, people reported feeling the ground and buildings shaking for hours. There were no immediate reports of injuries or the extent of the damage in Tonga, but online videos showed huge waves in coastal areas, swirling around homes and buildings.

Communications and power were reportedly out across Tonga’s main island, and the government have called up military reserves to assist with the response to the disaster.

“The size of these waves means the threat is for the marine environment for the east coast of Australia, and for land on Lord Howe Island and Norfolk Island; however the situation will be closely monitored and warnings updated as required. There will be many waves and the first wave may not be the largest,” said the Bureau of Meteorology.

“People in land warning zones are strongly advised to move 1 kilometre inland or go to high ground at least 10 metres above sea level. Significant sea-level variations are likely for hours and even days, and tsunami waves are more powerful than ordinary waves of the same size,” the statement said. 

Tsunami – Surge in Ventura Harbor, California

Update 9:58 am#tsunami #TsunamiAdvisory @nws @NWSLosAngeles #ventura #california pic.twitter.com/CugSzz7t0q

— Wave Talkers (@wavetalkers) January 15, 2022

In Santa Cruz, tidal surges of more than a metre flooded the harbor, and forced people on boats to scramble to safety and caused the cancellation of a surf contest at Monterey Bay.

So far no casualties have been reported as a result of the blast or subsequent tsunami. 

More to come on this.