STUDY: ‘Global warming could trigger the next ice age’ – ‘Earth’s climate control system may cool so hard after warming that it freezes the planet over’

You better drive your SUV more miles to reheat the planet!

Global warming could trigger the next ice age –

Earth’s climate control system may cool so hard after warming that it freezes the planet over.https://t.co/esqq4s4Mem pic.twitter.com/isUwJP7jJp

— Marc Morano (@ClimateDepot) December 27, 2025

https://www.sciencedaily.com/releases/2025/12/251221043231.htm

Date:

December 21, 2025

Source: University of California – Riverside

Summary:

Scientists have uncovered a missing feedback in Earth’s carbon cycle that could cause global warming to overshoot into an ice age. As the planet warms, nutrient-rich runoff fuels plankton blooms that bury huge amounts of carbon in the ocean. In low-oxygen conditions, this process can spiral out of control, cooling Earth far beyond its original state. While this won’t save us from modern climate change, it may explain Earth’s most extreme ancient ice ages.

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.

How Rock Weathering Helps Regulate Climate

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.

“As the planet gets hotter, rocks weather faster and take up more CO₂, cooling the planet back down again,” said Andy Ridgwell, a UC Riverside geologist and co-author of the study published in Science.

As human activity continues to add CO₂ to the atmosphere, the planet is expected to keep warming in the near term. The researchers’ model suggests that a cooling rebound will eventually follow. However, this future cooling is likely to be less extreme because higher oxygen levels reduce the strength of the nutrient feedback in the oceans.

“Like placing the thermostat closer to the AC unit,” Ridgwell added. Even so, the effect could be enough to bring forward the beginning of the next ice age.