Written by |
Asim Ismail |
Tuesday, November 22, 2022 – 01:00 PM
A new study finds that Earth can regulate its temperature over hundreds of thousands of years to keep it within a constant range, given that the planet has a “constant feedback” mechanism capable of preventing the climate pendulum from swinging too far in either direction over long time scales.
This is thought to be done through “silicate weathering” – a geological process during which the slow, continuous weathering of silicate rock involves chemical reactions that draw carbon from the atmosphere into ocean sediments, thereby trapping the gas in the rock.
The findings, published 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.
Global temperature stability phenomena
The researchers applied a mathematical analysis to determine whether the data revealed any patterns that would show stabilization phenomena for maintaining global temperatures over a very long time line.
They found that there appears to be a consistent pattern whereby the planet’s temperature fluctuations moderate over hundreds of thousands of years. This duration is similar to the time scales over which silicate weathering is thought to operate.
Why has life survived so long?
He explained that one of the arguments is that we need some kind of stabilization mechanism to maintain temperatures suitable for life, “but the data did not prove that such a mechanism has consistently controlled the Earth’s climate.”
Through previous research, scientists have observed the movement of carbon in and out of the Earth’s surface environment to remain relatively even – despite fluctuations in global temperatures.
changes to reduce carbon emissions
Scientists believe the planet is currently going through a period of warming and have urged policymakers to enact a range of changes to reduce carbon emissions or become carbon neutral.
Arnschedt and colleagues analyzed the 66-million-year history of average global temperatures to look at a range of different time scales, including hundreds of thousands, to see if any stabilizing patterns emerged at each time scale.
“To some extent, it’s as if your car is accelerating down the street, and when you hit the brakes, you slide for a long time before coming to a stop,” Daniel Rothman, a professor of geophysics at the Massachusetts Institute of Technology, said in a statement.
“There is a time scale in which frictional resistance, or stable feedback, begins when the system returns to a steady state,” he added.
Although scientists have long suspected that silicate ‘weathering’ could help maintain the planet’s carbon cycle, this is the first time they have observed direct evidence of the mechanism.
“On the one hand, it’s a good thing because we know that global warming today will eventually be canceled out by these stabilizing reactions,” explained Ernschidt. “But on the other hand, it will take hundreds of thousands of years for that to happen, so it’s not fast enough to solve our current problems.” “.
One noteworthy finding in the study is that over much longer time scales, more than a million years, the data did not reveal any stable feedbacks – which begs the question: what kept global temperatures in check?
“There is an idea that serendipity may have played a major role in determining why life persisted after more than 3 billion years,” Rothman said.
“There are two camps: some say random chance is a good enough explanation, others say there must be stable reactions,” said Arnschedt.
“We’re able to show it directly from the data, that the answer is probably somewhere in between. In other words, there was some stability, but it’s also possible that pure luck played a role in keeping Earth consistently habitable,” he added.