Melting polar ice is slowing the Earth's rotation

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Global warming has slightly slowed the Earth’s rotation — and it could affect how we measure time.

A study published Wednesday found that the melting of polar ice — an accelerating trend driven primarily by human-caused climate change — has caused the Earth to spin less quickly than it would otherwise.

The author of the study, Duncan Agnew, a geophysicist at the Scripps Institution of Oceanography at the University of California San Diego, said that as ice at the poles melts, it changes where the Earth’s mass is concentrated. The change, in turn, affects the planet’s angular velocity.

Agnew compared the dynamic to a figure skater twirling on ice: “If you have a skater who starts spinning, if she lowers her arms or stretches out her legs, she will slow down,” he said. But if a skater’s arms are drawn inward, the skater will twirl faster.

Less solid ice at the poles, then, means more mass around the equator — Earth’s waist.

“What you’re doing with the ice melt is you’re taking water that’s frozen solid in places like Antarctica and Greenland, and that frozen water is melting, and you move the fluids to other places on the planet,” said Thomas Herring, a professor of geophysics at the Massachusetts Institute of Technology who was not involved in the new study. “The water flows off towards the equator.”

The study suggests, in other words, that human influence has monkeyed with a force that scholars, stargazers and scientists have puzzled over for millennia — something long considered a constant that was out of humanity’s control.

“It’s kind of impressive, even to me, we’ve done something that measurably changes how fast the Earth rotates,” Agnew said. “Things are happening that are unprecedented.”

His study, which was published in the journal Nature, suggests that climate change is playing a significant enough role in the Earth’s rotation to counteract an opposing trend. Because of a combination of factors, the Earth has begun to spin faster in recent decades, a temporary trend that has prompted scientists for the first time to consider subtracting a single “negative leap second” from clocks worldwide as soon as 2026. But the melting of polar ice has delayed that possibility by about three years, according to Agnew.

If timekeeping organizations do eventually decide to add a negative leap second, the adjustment could disrupt computer networks.

The reason leap second adjustments have historically been needed is that even without climate change, Earth’s daily rotation has trended slower over millions of years, even though it may seem constant.

I guess we should all just unalive ourselves. then. Everything in the world is a horrible mess and it will never get better and there is nothing to look forwards to.