Overview
- The peer‑reviewed Nature Communications study reports record formaldehyde in the 2022 Hunga Tonga plume seen by TROPOMI and VIIRS and tracked for about ten days to South America.
- Formaldehyde’s persistence in the cloud signals rapid methane breakdown, with about 900 metric tons per day removed for roughly ten days against an estimated 300–330 gigagrams emitted by the eruption.
- Scientists tie the removal to reactive chlorine atoms produced when seawater thrown up by the submarine blast mixed with iron‑rich ash under sunlight, which then oxidized methane.
- The team retrieved formaldehyde by tailoring Sentinel‑5P TROPOMI data and cross‑checking with VIIRS, solving a common hurdle of weak methane observations over dark ocean surfaces.
- The findings point to a way to confirm engineered methane‑removal efforts from space, though the volcanic cleanup was limited and chlorine chemistry can damage stratospheric ozone.