Rapid Himalayan Glacial Erosion Releases CO2 From Pyrite Oxidation

Gist Traditionally, Himalayan erosion was thought to cool the Earth as newly exposed silicate minerals absorbed atmospheric carbon dioxide and locked it away in ocean sediments. However, a recent collaborative study reveals that rapid glacial erosion also exposes pyrite minerals, triggering a chemical cascade that releases massive amounts of CO2 into the atmosphere. This fundamentally alters our understanding of the geological carbon cycle, demonstrating that steep, glacier-fed mountainous regions are net carbon sources rather than sinks, potentially accelerating long-term climate warming. Background The continuous tectonic collision between the Indian plate and the Eurasian plate thrusts up the Himalayas, leading to constant erosion that exposes fresh minerals. For the past 50 million years , scientists believed this erosion primarily cooled the Earth through silicate weathering : exposed silicate minerals react with atmospheric CO2, wash into river systems, and eventually lock the carbon into seafloor sediments. The Himalayas also contain substantial deposits of pyrites iron sulfides . Before this study, the massive scale at which pyrite oxidation counteracts silicate weathering in glacial environments was not fully quantified. Key Pointers The chemical cascade…