The Earth’s rotation is slowing down due to climate change, researchers say

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Previously, research had shown that we had influenced the tilt of the Earth by pumping up groundwater, but now we are also said to have changed the rotation speed of our planet with climate change.

Rising temperatures, say researchers in Nature, are causing more ice shelves to melt, forcing the Earth’s water mass to rearrange. Those thick sheets of ice have a pulling gravitational effect on the oceans. According to this study, if those plates disappear and the meltwater moves, the Earth’s rotation speed will decrease.

Is that that bad? Well, it certainly has a possible effect on our clocks in the long term. In just a few years, we may have to remove a leap second to keep time as we keep it accurate.

A leap second has often been added to compensate for changes in the Earth’s rotation. Then the last minute of that day lasts 61 seconds, written as 23:59:60, but in this case a leap second should be removed.

Over the past 50 years, the Earth has actually been spinning faster, but the slowdown caused by the melting ice shelves may have masked that all along. If there had been no warming, this researcher argues, we would have had to subtract a leap second much earlier. Now he thinks this will be the case in 2028 or 2029.

All this does not have much impact on household clocks, perhaps at most on telecommunications or other systems that depend on very precise time determination. It has already been suggested to stop using the leap second correction altogether, also because the rotation of the Earth is constantly changing.

Perhaps, a Harvard scientist responds to the study, we should ask ourselves whether we should cling so hard to the Earth as the keeper of time. “Do we continue to correct, or do we just accept these irregularities?”

Read more about the research here: Melting ice solves leap-second problem – for now