Significant damage but no casualties for the moment. The tsunami caused by the powerful eruption on Saturday of Hunga Tonga-Hunga Ha’apai, an underwater volcano in the Tonga Islands, in the South Pacific Ocean, certainly devastated certain coasts but would not have taken away human lives. “The tsunami had a significant impact on the northern coastline of Nuku’alofa”, the capital of the Tonga Islands, “with boats and large rocks washed up on the shore”, but no casualties were reported, according to New Zealand Prime Minister Jacinda Ardern. The Pacific Tsunami Warning Center (PTWC) said overnight Saturday to Sunday that the tidal wave threat was “generally past” for countries bordering the ocean, even if slight variations in sea level remain possible for a few hours.
“Nuku’alofa is covered in a thick cloud of volcanic ash, but otherwise the situation is calm and stable”, added the New Zealand Prime Minister, after contacting the embassy of her country in Tonga. She added that the extent of the damage was difficult to assess in the small Pacific kingdom as communications were cut. Tonga needs a water supply, she added, because “the ash cloud caused contamination.” New Zealand will send a military reconnaissance aircraft to fly over the area on Monday if the volcanic ash cloud permits.
Waves to Chile
Waves of 1.2 meters swept through Tonga’s capital, where residents said they fled to higher ground, leaving behind flooded homes as rocks and ash fell from the sky. Stunning views from space showed the timing of Saturday’s eruption of Hunga Tonga-Hunga Ha’apai, on one of Tonga’s uninhabited islands: a huge mushroom of smoke and ash, and a wave immediately unleashed. The eruption triggered tsunamis in the Pacific, with waves of 1.74 meters measured in Chanaral, Chile, more than 10,000 kilometers away, and smaller waves observed along the Pacific coast, the Alaska to Mexico. Waves of about 1.2 meters hit the Pacific coast of Japan.
In California, the city of Santa Cruz was hit by flooding from a tidal wave generated by the tsunami, according to videos shared by the US National Weather Service. Peru, where “abnormal waves” were observed, according to Civil Defense, closed 22 ports as a precaution and the police indicated having rescued 23 people on the coast, without specifying under what circumstances.
The Hunga-Tonga-Hunga-Ha’apai submarine volcano, located about 65 km from the Tongan capital Nuku’alofa, had emerged during an eruption in 2009, and had spewed so many large boulders and ash into the air in 2015 that a new island two kilometers long by one kilometer wide and 100 meters high was formed when they were deposited. The United States Geological Institute (USGS) recorded Saturday’s eruption as equivalent to a magnitude 5.8 earthquake at zero depth. The eruption lasted eight minutes and sent plumes of gas, ash and smoke several miles into the air.