Overview
- An international team reports in Nature Communications that the 2022 Hunga Tonga plume oxidized part of its own methane.
- Using ESA’s Sentinel‑5P TROPOMI instrument, they detected record formaldehyde inside the plume and followed the cloud for about 10 days to South America.
- The study estimates the eruption released roughly 300–330 gigagrams of methane and that reactive chemistry removed about 900 metric tons each day while the cloud lasted.
- Researchers tie the removal to seawater salt mixing with volcanic ash under sunlight, which made chlorine radicals that break down methane, similar to a dust–sea‑spray process seen over the Atlantic.
- The authors say this pathway should be built into methane budgets and could guide engineered cleanup, though they warn about ozone harm and the challenge of proving net removal over the ocean.