Researchers at UC Riverside say they have identified a critical gap in how scientists have long understood Earth’s carbon recycling system. By filling in this missing piece, they now believe that periods of global warming can swing too far in the opposite direction, potentially setting the stage for an ice age.
For decades, scientists have thought Earth’s climate was regulated by a slow but dependable natural process driven by rock weathering. This mechanism was seen as a stabilizing force that kept temperatures from drifting too far in either direction.
In this process, rain absorbs carbon dioxide from the atmosphere and then falls onto exposed land surfaces. As the water interacts with rocks, especially silicate rocks such as granite, it gradually breaks them down. The dissolved material, along with the captured CO2, is carried into the oceans.
Once there, the carbon combines with calcium released from the rocks to form shells and limestone reefs. These materials settle on the ocean floor, locking carbon away for hundreds of millions of years and slowly reducing the amount of carbon dioxide in the atmosphere.
