A new study led by the University of Oxford has overturned the view that natural rock weathering acts as a CO2 sink, indicating instead that this can also act as a large CO2 source, rivaling that of volcanoes. The results, published today in the journal Nature, have important implications for modeling climate change scenarios.

https://phys.org/news/2023-10-ancient-carbon-dioxide-world-volcanoes.html

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Rock organic carbon oxidation CO2 release offsets silicate weathering sink

https://www.nature.com/articles/s41586-023-06581-9