While the Earth has been spinning for billions of years, it hasn’t always spun at the same speed — it’s been steadily slowing down. But now, it’s starting to speed up again, and global warming may be to blame. Researchers have found that 2021 will be shorter than past years due to the increased speed of the Earth’s rotation.
Many questions have arisen about what the planet’s slowing rotation means for humanity in the long run, and what factors could cause the Earth to start spinning faster. The research points to climate change as the culprit.
Paul Delaney, York astronomy and physics professor, explains: “As the planet warms and ice melts from a number of places including the polar ice caps, the redistribution of this weight (ice mass) into water that flows and distributes around the planet results in the increasing rate of planetary rotation.”
Delaney also adds that this theory is still being investigated. Other factors could play into the speed of Earth’s rotation, such as earthquakes, winds, and ocean tides.
This change in rotation speed will result in a fraction of a second being lost in each day. By the end of a year, atomic clocks — which measure every precise second of a year — will have accumulated a lag of 19 seconds.
While this change won’t affect the day-to-day activities of people, it does pose a challenge for GPS satellites, in which atomic clocks won’t consider Earth’s change in speed. This could result in issues for smartphones and computers, such as the New York Stock Exchange crash of June 30, 2015 which lasted for an hour. That crash resulted from a single second being added to the day.
All this raises the question of whether the Earth’s faster rotation is something to worry about.
“Not at all!” York Geodesy and Professional Engineering Professor Spiros Pagiatakis says, likening the amount of time fluctuation to a “needle in a haystack.”
“The length of the day will continue to fluctuate periodically by very tiny amounts of the order of a few to several tens of microseconds. The Earth’s spin rate continues to decrease overall much more rapidly, primarily due to tides induced by the Moon and the Sun,” Pagiatakis continues.
Delaney echos Pagiatakis’s statements, reassuring those concerned that the change is not very drastic. “The current speed up in our axial rate is likely short term and may well be caused by climate change as mentioned earlier. A similar overall rotation rate increase for a full year occurred in 1937 when climate change was not such an issue.”
“It is surprising that the recent news has made such a big splash about small fractions of a millisecond,” adds Pagiatakis. “The Earth has been slowing down irregularly by close to one second every 18-20 months that nobody notices or talks about.”
