Hunga Tonga volcanic plume destroyed methane, study finds

Researchers have discovered that the massive volcanic plume from the January 2022 Hunga Tonga-Hunga Ha’apai eruption appeared to destroy methane, a potent greenhouse gas, as it moved through the atmosphere. A study published in Nature Communications utilized satellite observations to identify record-high concentrations of formaldehyde within the cloud. Because formaldehyde is a short-lived chemical produced during the breakdown of methane, its presence served as a chemical fingerprint for active methane destruction.

Scientists tracked the cloud for ten days as it traveled toward South America, concluding that the volcanic ash was capable of continuously breaking down methane at a rate of approximately 900 megagrams per day. This removal rate is comparable to the methane emissions of two million cows. The findings suggest that volcanic activity may have an unexpected role in atmospheric chemistry and could provide insights into natural processes that accelerate the reduction of methane, which is a significant contributor to global warming.