EARTH.COM - Earth has never stood still when it comes to climate. For billions of years, our planet has cycled between heat and cold, shaping the environment where life evolved.
But new research from UC Riverside (UCR) reveals that the story of Earth’s carbon balance is more complicated than once believed.
The findings suggest that global warming could eventually tip into the opposite extreme – another ice age.
Rocks regulate Earth’s climate
The common scientific view has been that Earth regulates temperature through rock weathering. When rainwater absorbs carbon dioxide, it interacts with rocks on land, especially silicate-rich ones like granite.
This chemical process dissolves minerals, and the captured carbon eventually travels to the ocean. There, it combines with calcium, forming shells and limestone reefs that lock away carbon for hundreds of millions of years.
“As the planet gets hotter, rocks weather faster and take up more CO₂, cooling the planet back down again,” said Andy Ridgwell, a UCR geologist and co-author of the study.
This system works slowly but reliably, helping to stabilize climate over geological timescales. Yet history shows it is not always enough.