Earth’s Days Are Getting Longer Faster Than Ever, and Climate Change Is to Blame

Did you know Earth's days are getting longer? A new study links this unprecedented slowdown in our planet's rotation to climate change and rising sea levels. Learn how this affects GPS and our future.

It may sometimes feel like the days are dragging, and now scientists say there might be some truth to that feeling. A new study by researchers from the University of Vienna and ETH Zurich suggests that Earth's days are slowly getting longer, and the rate of this change is faster than anything seen in millions of years.

The study shows that the length of a day is increasing by about 1.33 milliseconds every century. Although this change seems very small, the researchers say it's 'unprecedented' in the last 3.6 million years of Earth's history. According to the team, human-driven climate change is the main reason behind this.

Rising Sea Levels

As the planet warms up, polar ice sheets and glaciers are melting, leading to rising sea levels. This process is slowing down Earth's rotation, similar to how a figure skater spins more slowly when they stretch their arms out. In the case of Earth, melted water from the poles is moving towards the equator, shifting the planet's mass farther from its axis, which causes the planet to spin more slowly.

Professor Benedikt Soja, a co-author of the study from the University of Vienna, told the Daily Mail: “While natural cycles caused variations in the past, the current rate of change, due to human impact, is so rapid that it stands out in climate history. Only one time – around 2 million years ago – the rate of change in length of day was nearly comparable, but never before or after that has the planetary "figure skater" raised her arms and sea–levels so quickly as in 2000 to 2020.”

Although the length of a day has never been exactly 24 hours, these minor shifts usually have little effect. However, Professor Soja warns that even small changes can impact systems that rely on precise timing, such as GPS, satellite navigation, space missions, and atomic clocks.

Dangers of Climate Change

The researchers also looked at fossilized remains of single-celled organisms called benthic foraminifera. Their shells contain chemical clues about past sea levels, which the scientists used in a physics-informed machine learning model to reconstruct changes in day length over the last 3.6 million years.

Their findings show that Earth's rotation has always varied naturally as ice sheets expanded and contracted. However, the speed at which days are now getting longer is unmatched in geological history. Human-induced climate change is now a stronger force affecting the planet's rotation than natural factors. By the late 21st century, days could lengthen by 2.62 milliseconds per century, surpassing the influence of the Moon.

Professor Soja concludes that even milliseconds matter when it comes to technology that depends on precise timekeeping. Monitoring these changes is crucial, because climate change is gradually reshaping not just our environment, but the very rhythm of our planet.