A giant volcano eruption blanketed the Polynesian island of Tonga in ash, and NASA specialists now estimate that the eruption's strength was hundreds of times that of the Hiroshima nuclear bomb.

NASA scientist Jim Garvin and his colleagues said in an analysis that the amount of energy released by a Tonga volcano from late December 2021 to mid-January 2022 was comparable to between 4 and 18 megatons of TNT.

Garvin and his colleagues calculated the figure based on how much rock was removed, how resistant it was, and how high the eruption cloud was blown into the atmosphere at various speeds.

According to CNN, NASA scientists believe that Mount St. Helens' 1980 eruption unleashed 24 megatons of energy. University of Auckland volcanologist Shane Cronin told Radio New Zealand that Tonga's latest eruption is the most intense volcanic explosion on Earth in more than 30 years, following Mount Pinatubo's 1991 (per Space.com).

Undersea Volcano Erupts Off Of Tonga
(Photo: Dana Stephenson//Getty Images)
NUKU'ALOFA, TONGA - MARCH 18: An undersea volcano is seen erupting off the coast of Tonga, sending plumes of steam, ash, and smoke up to 100 meters into the air, on March 18, 2009, off the coast of Nuku'Alofa, Tonga. The volcano, which is situated approximately 6 miles off of the main Tongan island of Tongatapu, is one of around 36 undersea volcanos clustered in the area. There is currently no danger to residents of the island as the gases are blown offshore, and residents noted the eruptions began on Monday after a series of sharp earthquakes were felt in the capital.


Tonga Volcano Eruption as Seen on NASA's Satellite

The Hunga-Tonga-Hunga-Ha'apai volcano erupted 25 miles into the atmosphere. The New York Times said it generated approximately 50-foot tsunami waves that slammed Tonga's main island areas and blasted ripples throughout the Pacific. The explosion also destroyed the country's internet cable, effectively shutting off contact to the isolated archipelago for days.

According to Live Science, scientists utilized a mix of satellite pictures and on-the-ground assessments to quantify the event's strength. The amount of rock removed during the explosion and the height and size of the cloud were all factors considered by the researchers.

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The Hunga Tonga-Hunga Ha'apai volcanic island was formerly two separate landmasses, but they were linked in 2015 by an eruption. Little explosions contributed more land to the islands before the volcano quieted down for nearly a week in late December 2021.

Then, ABC News said a strong eruption ravaged the new land in the early morning hours of January 14. Smithsonian's Global Volcanism Program volcanologist Ed Venzke told NASA said they noted substantial chunks of the two older islands were affected. The remaining islands make up the top of the undersea volcano, which rises more than a mile from the seafloor and is 12 miles wide. The blast submerged the main eruptive vent underwater, perhaps only in a shallow pool, but deep enough to make the January 15 explosion all the more powerful.

Experts Explain Why Tonga Acted That Way

The combination of hot magma and saltwater, which creates strong steam blasts, is one explanation for the magnitude of the cloud created by the blast. Surtseyan eruptions are hydromagmatic eruptions that occur in shallow oceans or lakes.

Garvin and the volcanology team feel that this sort of occurrence merits its own title, according to a release. For the time being, they're referring to it as an 'ultra Surtseyan' eruption."

Unlike Mount Pinatubo's eruption, which lasted hours and expelled ash and smoke, NPR said the explosion in Tonga lasted less than an hour. Experts do not believe the blast from Hunga Tonga-Hunga Ha'apai will trigger any short-term climatic changes, as some earlier volcanic eruptions did.

Most Tongans have been harmed by falling ash since the explosion, and three individuals were killed in the tsunami last week. CDC said breathing smoke and ash may inflame and damage heart and lungs tissue, as well as irritate eyes and skin, posing a health concern to Tonga's more than 100,000 citizens.

RELATED ARTICLE: Tonga Underwater Volcanic Eruption Hints That Large Hunga Caldera Has Awoken 

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