Volcanic Plume Reveals a Natural Route to Methane Destruction in the Atmosphere
Scientists studying the 2022 Hunga Tonga eruption found a high-altitude chemical reaction—driven by volcanic ash, seawater salt, and sunlight—that produced chlorine radicals capable of destroying methane in the stratosphere. Satellites tracked a lasting formaldehyde signal and estimated about 900 tons/day of methane removal, though far more methane entered the atmosphere than was destroyed. The work shows methane oxidation can be measured from orbit, with implications for methane budgets and potential future deliberate removal.