Tonga Volcano Ejected Record Amount of Water Into Stratosphere, Could Have Warming Effect

A satellite image of the underwater volcanic eruption in Tonga reaching into the stratosphere on Jan. 15, 2022. AAP Image/Tonga Meteorological Services, Government of Tonga

The violent eruption of an underwater volcano near Tonga in January blasted a record amount of water vapor into the atmosphere, but not all scientists agree about the exact amount and its possible effects.

Tonga was hit by an underwater eruption of the Hunga Tonga-Hunga Ha’apai volcano and subsequent tsunami on Jan. 15, which wiped out an entire village on one of Tonga’s small outer islands and killed at least three people.

Holger Vomel, a senior scientist at the National Center for Atmospheric Research in Boulder, Colorado, was the lead author of a study on the Tonga volcanic eruption published on Sept. 22 in the academic journal Science.

According to that study, the volcanic eruption was so violent that its plume penetrated into the stratosphere, blasting at least 50 teragrams (50 billion kilograms) of water vapor.

The stratosphere is the layer of atmosphere between 8 and 33 miles above the earth’s surface.

“This event raised the amount of water vapor in the developing stratospheric plume by several orders of magnitude and possibly increased the amount of global stratospheric water vapor by more than 5 percent,” the paper reads.

A satellite image shows the Hunga Tonga-Hunga Ha'apai volcano after its main eruption, in Hunga-Tonga-Hunga-Ha'apai, Tonga, on Jan. 18, 2022. Satellite Image 2022 Maxar Technologies/Handout via Reuters

In a NASA study conducted at the agency’s Jet Propulsion Laboratory in Southern California, researchers claim the amount of water vapor released was about 146 teragrams, nearly three times more than the amount cited in the Science study.

NASA said the “enormous” plume of water vapor is the equivalent of more than 58,000 Olympic-sized swimming pools.

No Comparison, Says NASA Scientist

“We’ve never seen anything like it,” Luis Millan, an atmospheric scientist at the Jet Propulsion Laboratory, said in the NASA report. He led the study of the water vapor brought on by the Tonga volcanic eruption.

In the past 18 years, only two other volcanic eruptions sent “appreciable amounts” of water vapor to such high altitudes—the 2008 Kasatochi event in Alaska and the 2015 Calbuco eruption in Chile—according to NASA.

Both eruptions were “mere blips” compared to the Tonga volcanic eruption, and the water vapor produced dissipated quickly. Water vapor from the Tonga volcano could remain in the stratosphere for “several years,” NASA said.

“This extra water vapor could influence atmospheric chemistry, boosting certain chemical reactions that could temporarily worsen depletion of the ozone layer. It could also influence surface temperatures,” the agency stated.

NASA said that the Tonga volcano did not inject large amounts of aerosols into the stratosphere. The massive amounts of water vapor from the eruption could have “a small, temporary warming effect,” the agency said, but the effect will dissipate when the extra water vapor cycles out of the stratosphere.

The Tonga volcano was the largest atmospheric explosion documented since the 1883 Krakatoa eruption in Indonesia, which generated long-range audible sound that could be heard 10,000 kilometers (6,200 miles) away in Alaska.

NASA said in April that the Tonga volcano eruption was “hundreds of times” stronger than the Hiroshima nuclear explosion.