New research reveals how the Earth might overcorrect for global warming.
For a long time, scientists believed that the gradual breakdown of silicate rocks played the leading role in regulating Earth’s climate. In this natural process, rain absorbs carbon dioxide (CO2) from the atmosphere and falls onto exposed rock surfaces, where it slowly dissolves the minerals. The resulting chemical reactions carry carbon and calcium into the oceans, where they serve as building blocks for shells and coral reefs. Over millions of years, these materials accumulate on the seafloor, locking away carbon deep within the Earth.
“When the planet warms, rocks weather faster and absorb more CO2, allowing the Earth to cool down again,” explains Dominik Hülse.
However, throughout Earth’s history, there have been times when the entire planet was shrouded in snow and ice. The researchers note that these extreme glaciations cannot be explained by rock weathering alone, meaning other mechanisms must have contributed to the planet’s deep freeze.
One key factor appears to be how carbon is stored in the ocean floor. As atmospheric CO2 levels rise and the planet warms, more nutrients, particularly phosphorus, are carried into the oceans. These nutrients fuel the growth of algae that capture carbon through photosynthesis. When the algae die, they sink to the seabed, carrying the trapped carbon with them.
Feedback Loops and Oxygen Loss
In a warmer world with enhanced algae growth, however, the oceans also lose oxygen, which results in the recycling of phosphorus rather than it being stored long-term in the sediments. This creates a feedback loop: the availability of more nutrients in the water results in more algae, whose decomposition in turn consumes more oxygen, causing even more nutrients to be recycled. At the same time, large amounts of carbon are buried in the sediments, which causes the Earth to cool.
For several years, Hülse and Ridgwell have been refining a computer model of the Earth System by incorporating more of these processes. “This more complete Earth System model does not always stabilize the climate gradually after a warming phase, rather it can overcompensate and cool the Earth far below its initial temperature — a process that can still take hundreds of thousands of years, however. In the computer model of the study, this can trigger an ice age. With the silicate weathering alone, we were unable to simulate such extreme values,” explains Dominik Hülse.
Ancient Ice Ages and Atmospheric Oxygen
The study shows that lower oxygen concentrations in the atmosphere, which occurred in the geological past, could have triggered stronger nutrient feedbacks, and thus have caused the extreme ice ages of early Earth history.
As humans today add more CO2 into the atmosphere, the planet will continue to warm. But according to the scientists’ model, it could lead again to a cooling overshoot in the long run. However, the next event will likely be milder, because today’s atmosphere contains more oxygen than in the distant past, which dampens the nutrient feedback.
“At the end of the day, does it really matter much if the start of the next ice age is 50, 100, or 200 thousand years into the future?” asks Ridgwell. “We need to focus now on limiting ongoing warming. That the Earth will naturally cool back down is not going to happen fast enough to help us out.”
In the next step, Hülse wants to use the model to understand why the Earth System has, at times, recovered surprisingly quickly from past climate perturbations, and how interactions with the marine sediments contributed to this.
Reference: “Instability in the geological regulation of Earth’s climate” by Dominik Hülse and Andy Ridgwell, 25 September 2025, Science.
DOI: 10.1126/science.adh7730
The study was funded in part by the MARUM-based Cluster of Excellence “The Ocean Floor – Earth’s Uncharted Interface.”
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14 Comments
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This fr sounds like an earth problem 🧐👌🏻🧠
You are missing the entire problem….Humans Mycelium is gone because World Order, Central Bank, Moses’ descendents, Head of Jewish Order have eliminated it. Because it makes invincible. The Ocean circulates the mycelium from the land around the world. All we have to do is grow it and no Mass extinction and climate change. It was ALWAYs an Ice age drought equals Ice Age
Your comment makes no sense. Perhaps English is not your native language. Or, maybe the comment is a crude experiment at mimicking Large Language Model AI. In either case, I don’t think that you have contributed much. I expect someone with a PhD to be more articulate.
Could you explain this in layman’s language please
Try Engrish.
“When the planet warms, rocks weather faster and absorb more CO2, allowing the Earth to cool down again,”
However, when the oceans warm they cannot hold as much dissolved CO2 and it out-gases, increasing the amount in the atmosphere. At the same time, calcium carbonate precipitates, contributing to the amount sequestered. It is a complex dance of all the feedback loops where numbers matter. Where are the numbers?
“Over millions of years, these materials accumulate on the seafloor, locking away carbon deep within the Earth.”
An important point is that the ‘carbon’ is not permanently locked away. It is only temporarily sequestered, albeit for millions of years. As demonstrated by the famous White Cliffs of Dover in England and many other places, shifting tectonic plates can bring the carbonates back to the surface where they will be dissolved more quickly than the original original silicates from which they were derived. The only way that this process can be understood is by measurements that provide rates of change for the entire globe. Again, where are the numbers? Arm waving about general principles doesn’t cut it because rates are important!
These kinds of articles, based on lawyer words — could, might, may, possibly — without strict definitions as to the probabilities of events, are like sucker bets. That is, “Heads I win, tails you lose.” Even if anyone remembers the claim in the distant future, and it doesn’t happen as conjectured, one gets off free by simply saying, “We didn’t say it WOULD happen, only that it COULD happen.” That expands the possibility horizon so much that it becomes meaningless. Unless prohibited by some fundamental Law of Nature, the possibility still approaches infinity, saying little about the probability. I want to see the probability estimate, along with the margin of error, and a justification for the numbers. Otherwise, it is just ‘science fantasy.’
Any article containing the words “could, might, etc.” as you pointed out without supporting data to indicate the probability of occurrence aren’t worth the time reading. Being a retired person and conscious of this sort of scare mongering, I do put certain short term predictions in my calendar to see how they pan out on the dates given, should I live so long. So far, they are 100% wrong. As the saying goes, the probability that my cat will kill me as I sleep is very, very small; but not zero, but I don’t worry about it.
Since probability is essentially infinite, there is no dependability. Taking that into consideration, what the article proposes is just another one of the speculations crowding out real science, and concerns about what to do about the effects that are modifying food resources, ocean environment changes that threaten human population survival and cultural changes driven by political drives for power. Better to think about a way to inspire human thought to comprehend the obvious interrelationships that biology and physics reveal. Survival of the species may well depend upon it.
Well, given how in vain we are as a species, having us wiped out is not “overcorrection” – it’s more like justice. I feel sorry for the other animals, though.
On the other hand, how the hell do these guys know anything? They couldn’t even predict the stall in the warming trend during the 2010s. Clearly their models are still too simplified to be of any use prediction-wise.
Arm waving by scientists. Well, I suppose Newton got it wrong about gravity, but it was an interesting arm-wave. Had he realised that the entire universe did an upward shift so that it passed by the apple, he might have invented relativity around 300 years before Einstein.
The value of arm-waving is that it stimulates thought and experiment, even if it leads to complaints that that arm-waving does not worry overmuch about probability estimates and error bars. If we were bound and tied to probability estimates the Spanish inquisition would still hold sway. The then probability that the Bible spoke fundamental truths would still be having people burnt at the stake.
There is an important difference between arm waving that is conjecture, and arm waving that is claiming to be “settled science” without definitive evidence to support even a transient paradigm. Conjectures can be entertaining, but are of little value in predicting what WILL happen in the future.