Hunga Tonga Methane Breakdown Discovery

The January 2022 eruption of the submarine volcano Hunga Tonga–Hunga Haʻapai in the South Pacific, one of the most violent in modern times, revealed an unexpected natural mechanism for methane breakdown. Researchers, including Maarten van Herpen from Acacia Impact Innovation BV and Matthew Johnson from the University of Copenhagen, observed unusually high concentrations of formaldehyde in the volcanic plume using the TROPOMI instrument aboard the International — European Space Agency's Sentinel-5 Precursor satellite. Formaldehyde is an intermediate product of methane destruction. The theory suggests that salty seawater hurled into the stratosphere with volcanic ash, when exposed to sunlight, formed highly reactive chlorine atoms that broke down methane. This mechanism is similar to one previously discovered involving Sahara dust and sea salt. This finding, supported by Galvanize Climate Solutions, provides new insights into atmospheric chemistry and could inspire industry to develop new methods to artificially accelerate methane removal, offering a potential 'emergency brake' on global warming. Jos de Laat from the Netherlands — Royal Netherlands Meteorological Institute and Isabelle De Smedt from the Belgium — Royal Belgian Institute for Space Aeronomy also contributed to the study, which suggests that global methane budgets may need revision.