Muddying the waters: rock breakdown may play less role of a role in regulating climate than previously thought

The weathering of rocks at the Earth's surface may remove less greenhouse gases from the atmosphere than previous estimates, says new research from the University of Cambridge. People have spent decades looking on the continents for weathering - so maybe we now need to start expanding where we look Ed Tipper The findings , published in PNAS , suggest Earth's natural mechanism for removing carbon dioxide (CO₂) from the atmosphere via the weathering of rocks may in fact be weaker than scientists had thought - calling into question the exact role of rocks in alleviating warming over millions of years. The research also suggests there may be a previously unknown sink drawing CO₂ from the atmosphere and impacting climate changes over long timescales, which researchers now hope to find. Weathering is the process by which atmospheric carbon dioxide breaks down rocks and then gets trapped in sediment. It is a major part of our planet's carbon cycle, shuttling carbon dioxide between the land, sea and air, and influencing global temperatures. "Weathering is like a planetary thermostat - it's the reason why Earth is habitable. Scientists have long suggested this is why we don't have a runaway greenhouse effect like on Venus," said lead author Ed Tipper from Cambridge's Department of Earth Sciences.