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The impact of human-induced climate change is so huge that it’s actually messing with time, according to new research.

The melting of polar ice caused by global warming is changing the rate of Earth’s rotation and the increase in the length of each day, a trend that has accelerated this century, as humans continue to pump pollution that heats the planet, according to a study published Monday in the Proceedings of the National Academy of Sciences.

The changes are small—a matter of milliseconds a day—but in our high-tech, hyper-connected world, they have an important impact on the computing systems we rely on, including GPS.

This is yet another sign of the enormous impact humans have on the planet. “This is evidence of the seriousness of ongoing climate change,” said Surendra Adhikari, a geophysicist at NASA’s Jet Propulsion Laboratory and an author of the report.

The number of hours, minutes and seconds that make up each day on Earth is determined by the speed of the Earth’s rotation, which is affected by a complex knot of factors. These include processes in the planet’s liquid core, the continued impact of the melting of huge glaciers after the last ice age, and the melting of polar ice due to climate change.

For millennia, however, the influence of the moon has dominated, increasing the length of the day by a few milliseconds per century. The Moon exerts a gravitational force on the Earth, causing the oceans to swell toward it, gradually slowing the Earth’s rotation.

Scientists have previously linked melting polar ice to longer days, but new research suggests global warming is having a bigger impact on the weather than recent studies suggest.

In the past, the impact of climate change on the weather “was not so dramatic,” said Benedict Soya, study author and assistant professor of space geodesy at Switzerland’s ETH Zurich.

But that could change. If the world continues to pump out planet-warming pollution, “climate change could become the new dominant factor,” overtaking the role of the moon, he told CNN.

It works like this: as humans warm the world, glaciers and ice sheets melt and that meltwater flows from the poles to the equator. This changes the shape of the planet – flattening it at the poles and making it more convex in the middle – slowing its rotation.

The process is often compared to a spinning skater. When the skater pulls his arms to his body, they spin faster. But if they move their arms outward, away from their body, their rotation slows down.

The team of international scientists looked at a 200-year period, between 1900 and 2100, using observational data and climate models to understand how climate change has affected day length in the past and to project its role in the future.

They found that the impact of climate change on the length of the day has increased significantly.

Climate change-fueled sea-level rise has caused day length to vary between 0.3 and 1 millisecond during the 20th century. Over the past two decades, however, scientists estimate an increase in day length of 1.33 milliseconds per century, “significantly higher than at any time in the 20th century,” according to the report.

If the planet’s pollution continues to rise, warming the oceans and accelerating the loss of ice in Greenland and Antarctica, the rate of change will increase, the report said. If the world fails to curb emissions, climate change could increase the length of the day by 2.62 milliseconds by the end of the century – outpacing the moon’s natural effects.

“In just 200 years, we will have changed the Earth’s climate system so much that we will be witnessing its impact on the very way the Earth rotates,” Adhikari told CNN.

A few milliseconds of extra time a day may be imperceptible to humans, but it has an impact on technology.

Accurate timekeeping is vital to GPS, which everyone with a smartphone will have, as well as other communication and navigation systems. They use highly precise atomic timing based on the frequency of certain atoms.

Since the late 1960s, the world has started using Coordinated Universal Time (UTC) to set time zones. UTC relies on atomic clocks, but still keeps up with the planet’s rotation. This means that at some point the “leap seconds” must be added or subtracted to maintain alignment with the Earth’s rotation.

Some studies also suggest a link between increasing day length and increase in earthquakes, said Mostafa Kiani Shahvandi, study author and geoscientist at ETH Zurich. But the link remains speculative and much more research needs to be done to establish a clear link, he told CNN.

A report on the same topic published in March has concluded that while climate change is increasingly slowing the Earth’s rotation, processes in the Earth’s core may be more important and actually speed it up, shortening the length of the day.

“What we’ve done is go a little further and reassess those trends,” Shahwandi said. They found that the influence of the molten core was offset by climate change.

Duncan Agnew, a professor of geophysics at UC San Diego and an author of the March study, said the new the study is still linked to his research “and is valuable because it extends the result further into the future and considers more than one climate scenario.”

Jacqueline McCleary, an assistant professor of physics at Northeastern University who was not involved in the study, said the new research helps inform “a decades-long debate about exactly what role climate changes will play in the changing length of the day.”

Although there is now general agreement that climate change will have a “net effect of lengthening the day,” she told CNN, there is still uncertainty about which weather-affecting processes will dominate this century. That study concluded that climate change is now the second most dominant factor, she said.

This is a sobering conclusion, said ETH Zurich’s Soja. “We have to consider that we are now influencing the Earth’s orientation in space so much that we are dominating effects that have been at work for billions of years.”