Warming across the Arctic is not only melting ice but it’s also causing another issue: Changing the speed at which the earth rotates, according to Duncan Agnew, a geophysicist with the Scripps Institution of Oceanography at the University of California, San Diego.
Watching an ice skater spin is a good metaphor for what’s happening with the earth’s rotation.
“That’s like the classic example of an ice skater that’s spinning: She has her arms overhead, moves her arms out and she slows down, and that’s what happening with the earth,” Agnew said.
Agnew says the warming over the Arctic that’s melting ice over Greenland and Alaska has been slowing down the earth’s rotation, which has impacted time. It’s one part of the earth’s dynamics that is impacting its rotation.
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“Every so often a second has had to be inserted to bridge the atomic-clock time, the time we use on our phones in sync with the rotation of the earth, and if the earth speeds up, which has been happening, a second has to be removed,” Agnew said.
He’s referring to a leap second. The last time there was a positive leap second was in 2016.
“So a leap second is when you take a minute and either put an extra second in or we take a second out, so instead of having 60 seconds, we either have 61 or 59,” Agnew said.
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But now for the first time, there are talks of a negative leap second and it’s because of the earth’s core.
“The core of the earth is speeding it up, and it’s speeding it up for 50 years,” Agnew said. “Who’s bigger? Well, right now the core is bigger, and the earth has been speeding up.”
If this continues, Agnew said, it will eventually get to the point where one second has to be removed from atomic time, which he said could happen at the end of the decade.
“So, we would have a minute that only has 59 seconds in it,” Agnew said.
It’s only one second, but in the world of technology, that's a long time. Agnew said financial transactions in the U.S. must be accurately timed to a 20th of a second.
“The electric power system, the financial markets, all kinds of things, massive amounts of internet commerce — all depend on very precise time,” Agnew said.
Meantime, according to Agnew’s work, this negative leap second could happen by the end of the decade, but it is still difficult to predict.
“Right now, the earth and atomic clock are in sync," Agnew said.
Regardless of what will happen, Agnew shared this link to climate change.
“What it is, is we’ve done something that’s causing something that’s changed what the entire earth does,” Agnew said
