(Common Dreams) A massive eruption in an undersea volcano, the Hunga Tonga-Hunga Ha'apai, 40 miles north of the South Pacific island of Tongatapu on Saturday caused a low-level tsunami and flooding on the island, the most populous in the Tonga archipelago. The tsunami spread out from there, causing one- to three-foot waves in Hawaii and some one-foot waves on the West Coast of the US and down to Chile. The waves created rip tides that endangered marinas and swimmers. Further eruptions cannot be ruled out.
At the moment, most volcanic eruptions are not related to the climate emergency, but events like this give us a taste of what will begin happening regularly if large Antarctic glaciers begin plopping into the ocean because of the coal and gasoline we burn daily. In fact, some of those glaciers could raise sea levels as much as six feet all by themselves, so their effects would be much worse. Some scientists believe that the Thwaite "doomsday glacier" could break up within only ten years.
Moreover, as the world's surface ice melts and the oceans rise, that will put more pressure on the earth's crust, so we will see increased vulcanism, and more tsunamis. So get used to it.
New Zealand Prime Minister Jacinda Ardern posted this photo of this behemoth of an eruption on her Facebook page.
(The Conversation) The Hunga-Tonga-Hunga-Ha'apai volcano has erupted regularly over the past few decades. During events in 2009 and 2014/15 hot jets of magma and steam exploded through the waves. But these eruptions were small, dwarfed in scale by the January 2022 events.
Our research into these earlier eruptions suggests this is one of the massive explosions the volcano is capable of producing roughly every thousand years.
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The latest eruption has stepped up the scale in terms of violence. The ash plume is already about 20km high. Most remarkably, it spread out almost concentrically over a distance of about 130km from the volcano, creating a plume with a 260km diameter, before it was distorted by the wind.
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…we could be in for several weeks or even years of major volcanic unrest from the Hunga-Tonga-Hunga-Ha'apai volcano. For the sake of the people of Tonga I hope not.
A rare volcano-triggered tsunami sparked by the eruption of Hunga Tonga-Hunga Ha'apai in Tonga could have been caused by shock waves or shifting underwater land, experts said Monday.
"A volcanic-source tsunami event is rare but not unprecedented," a post on the website for New Zealand's geological hazard monitoring system GNS said Monday.
GNS Tsunami Duty Officer Jonathan Hanson said it probably occurred in part thanks to a previous eruption of the same volcano one day earlier.
"It is likely that the earlier 14 January eruption blew away part of the volcano above water, so water flowed into the extremely hot vent," wrote Hanson.
"This meant that the Saturday evening eruption initially occurred underwater and exploded through the ocean, causing a widespread tsunami," he said.
The world's first inventory of subglacial lakes has been compiled by an international team led by the University of Sheffield, providing researchers with a comprehensive directory of where the lakes are and how they are changing in a warming climate.
Subglacial lakes can form underneath ice sheets or glacial valley regions. They can play a critical role in the speed at which ice flows into oceans and, when on land in mountainous regions, could pose a major risk to populations downstream if they were to drain and cause flooding and landslides.
It is believed that there are many thousands of subglacial lakes worldwide but, until now, their details were not collectively held and there was no clear picture on the size, stability and characteristics of the lakes.
An international team of researchers led by Dr. Stephen Livingstone, from the University of Sheffield's Department of Geography, has now cataloged data on almost 800 lakes in Antarctica, Greenland and Iceland, as well as in glacial valley regions such as the Alps.