![\"Tonga's](\"https:\/\/www.newsbeep.com\/uk\/wp-content\/uploads\/2026\/04\/tongas-strange-volcanic-eruption-was-even-more-massive-than-we-knew-1200x790.jpg\")
Tonga\u2019s strange volcanic eruption was even more massive than we knew. Credit: Getty<\/p>\n
That water vapor changed the rules. Typical large eruptions like Pinatubo release sulfur dioxide, which forms reflective particles that warm the stratosphere<\/a>. Hunga did the opposite. The extra water released heat to space, cooling wide regions of the stratosphere by 0.5 to 1 degree Celsius (0.9 to 1.8\u00b0F). A report from the University of Colorado Boulder<\/a> noted that this behavior contrasts sharply with every major eruption previously observed.<\/p>\n The Tallest Plume Ever Measured<\/p>\n The plume reached 35.4 miles into the sky, piercing the mesosphere, the layer where shooting stars burn up and most aircraft cannot fly. National Geographic<\/a> confirmed this as the highest volcanic plume ever recorded.<\/p>\n Why so violent? The Hunga caldera sat roughly 490 feet below the ocean surface. That depth was ideal: deep enough for seawater to be superheated by erupting magma, but shallow enough that ocean pressure did not muffle the explosion. <\/p>\n A study published in the Journal of Volcanology and Geothermal Research<\/a> proposed that the climactic blast was driven by gas forced hydraulic failure, not a simple magma water interaction. The reaction pulverized rock into fine particles and converted vast quantities of seawater into vapor that rode the eruption column into the upper atmosphere.<\/p>\n Seafloor surveys by New Zealand\u2019s National Institute of Water and Atmospheric Research estimated the blast excavated around 2.3 cubic miles of rock, which would make Hunga the largest eruption recorded in the past century. The crater deepened by approximately 2,300 feet, and pyroclastic flows radiated at least 50 miles from the rim, blanketing the ocean floor in fine white sediment and severing undersea communication cables that linked Tonga to the outside world.<\/p>\n Cooling the Stratosphere, Sparing the Surface<\/p>\n Most major volcanic eruptions warm the stratosphere because dark sulfate particles absorb incoming solar radiation. At Hunga, seawater intercepted most of the sulfur before it could escape upward. Only a small fraction reached high altitudes. The resulting sulfate signal was far weaker than Pinatubo\u2019s, while the water vapor signal was without precedent.<\/p>\n That water vapor acts like a radiator, sending heat back out to space. The cooling signal reached higher atmospheric layers in the months following the eruption.<\/p>\n Despite that upper-atmosphere disruption, surface temperatures<\/a> showed almost no response. Ground level cooling reached only about 0.05 degrees Celsius (0.09\u00b0F), far below the 0.25 to 0.5 degrees of surface cooling that Pinatubo produced.<\/p>\n![\"This](\"https:\/\/www.newsbeep.com\/uk\/wp-content\/uploads\/2026\/04\/1-tonga-eruption-1041.gif\")
<\/a>This looping video shows an umbrella cloud generated by the underwater eruption of the Hunga Tonga-Hunga Ha\u2019apai volcano on Jan. 15, 2022. Credits: NASA Earth Observatory\/Joshua Stevens\/GOES imagery\/NOAA and NESDIS<\/p>\n![\"Clouds](\"https:\/\/www.newsbeep.com\/uk\/wp-content\/uploads\/2026\/04\/clouds-of-ash-lingering-in-the-atmosphere-a-day-after-the-intense-explosion-of-hunga-tonga-hunga-haa.jpeg\")
An image from Jan. 16, 2022, shows the ash plume from the Hunga Tonga-Hunga Ha\u2019apai volcanic eruption that occurred the day before. Credit: NASA<\/p>\n