Earth can regulate its temperature over hundreds of thousands of years to keep them within a stable range, a new study confirms.
The planet contains a “stabilizing feedback” mechanism capable of preventing the climatic pendulum from swinging too much back and forth over long periods of time.
This is thought to be accomplished through ‘silicate weathering’, a geological process in which the slow and steady weathering of silicate rocks involves chemical reactions that pull carbon from the atmosphere and into ocean sediments, trapping thus the gas in the rocks.
The findings, published Wednesday in the journal Science Advances, are based on a study of paleoclimate data that records fluctuations in average global temperatures over the past 66 million years.
Earth can regulate its temperature over hundreds of thousands of years to keep them within a stable range, new study confirms
Scientists believe we are currently in a period of warming and have urged policymakers to adopt a series of changes to reduce carbon emissions or become carbon neutral. Above: Water levels in Lake Mead, Nevada, are the lowest since April 1937, when the reservoir was first filled, according to NASA
The researchers applied mathematical analysis to determine if the data revealed patterns that would show a stabilizing phenomenon to keep global temperatures in line over a very long timescale.
They found that there appears to be a consistent pattern in which the planet’s temperature variations smooth out over hundreds of thousands of years. This duration is similar to the time scales on which silicate weathering is thought to act.
“You have a planet whose climate has been subjected to so many dramatic external changes. Why has life survived all this time? One of the arguments is that we need some kind of stabilization mechanism to maintain temperatures suitable for life,” said Constantin Arnscheidt, graduate student in the Department of Earth, Atmospheric and Planetary Sciences. (EAPS) from MIT.
“But such a mechanism has never been shown from data to consistently control Earth’s climate.”
Through previous research, scientists have observed that the movement of carbon in and out of the Earth’s surface environment remains relatively balanced, despite global temperature variations.
Scientists believe we are currently in a period of warming and have urged policymakers to adopt a series of changes to reduce carbon emissions or become carbon neutral.
Arnscheidt and his colleagues analyzed the 66 million year average global temperature history to consider a range of different timescales, including tens of thousands and hundreds of thousands, to see if any stabilization patterns have emerged in each time scale.
“To some extent, it’s like your car speeding down the street, and when you brake, you slide for a long time before you stop,” Daniel Rothman, a professor of geophysics at MIT, said in a statement.
“There is a time scale over which frictional resistance, or a stabilizing feedback, kicks in as the system returns to a steady state.”
Although scientists have long suspected that silicate weathering may help maintain our planet’s carbon cycle, this is the first time they’ve seen direct evidence of the mechanism.
Arnscheidt and his colleagues analyzed the 66 million year average global temperature history to consider a range of different timescales, including tens of thousands and hundreds of thousands, to see if any stabilization patterns have emerged in each time scale. Above: A view of the fishing village in the coastal area of Chittagong Potenga in Bangladesh where a cyclone hit on October 25, 2022
“On the one hand, it’s a good thing because we know that today’s global warming will eventually be canceled thanks to this stabilizing feedback,” Arnscheidt explained. Above: A man rides a bike on a flooded Sausalito/Mill Valley bike path during the “King Tide” in Mill Valley, California
“On the one hand, it’s a good thing because we know that today’s global warming will eventually be canceled thanks to this stabilizing feedback,” Arnscheidt explained.
“But on the other hand, it will take hundreds of thousands of years, so not fast enough to solve our current problems.”
A remarkable finding from their work is that over much longer time scales, i.e. over a million years, the data revealed no stabilizing feedback – leading to the question: Controlled Global Temperatures?
“There is a notion that chance may have played a major role in determining why, after more than 3 billion years, life still exists,” Rothman offered.
“There are two camps: some say chance is sufficient explanation, and others say there must be stabilizing feedback,” Arnscheidt said.
“We are able to show, directly from the data, that the answer is probably somewhere in between. In other words, there was some stabilization, but sheer luck probably also played a part in keeping Earth permanently habitable.
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