Tonga's Enormous Volcanic Eruption Cleaned Up Part of Its Own Methane Emissions in 2022, Hinting at a Way to Fight Climate Change

This satellite image from January 16, 2022, reveals formaldehyde in blue. The volcanic plume from the Hunga Tonga–Hunga Ha apai volcano traveled over the South Pacific. van Herpen et al. (2026) Hunga Tonga–Hunga Ha’apai’s eruption in January 2022 was among the most violent volcanic eruptions of the modern era. New research reveals that the blast, located off Tonga in the South Pacific, was also a rather polite one, as the submarine volcano’s explosion came with a chemical reaction that disposed of some of its own methane emissions.

Scientists examined satellite images of the volcanic plume and found an unexpectedly high concentration of formaldehyde, a gas that temporarily forms when methane breaks down in the atmosphere. The finding, published in May in the journal Nature Communications, suggests that a methane clean-up process was taking place in the stratosphere in the wake of the eruption. Though further research is necessary to truly understand the chemistry at play, this natural mechanism could inspire artificial global warming interventions.

“We were able to track the cloud for ten days, all the way to South America. Because formaldehyde only exists for a few hours, this showed that the cloud must have been destroying methane continuously for more than a week,” Maarten van Herpen, a co-author of the study and a researcher at the Dutch consulting firm Acacia Impact Innovation BV, says in a statement. “It is known that volcanoes emit methane during eruptions, but until now it was not known that volcanic ash is also capable of partially cleaning up this pollution.”