麻豆影视

Skip to main content

Climate change is making each day slightly longer, and there's no sign it's going to stop, NASA says

Earth is seen from the Apollo 8 spacecraft in December 1968. (NASA) Earth is seen from the Apollo 8 spacecraft in December 1968. (NASA)
Share

Rising sea levels are making each day slightly longer, and there's no sign it's going to stop, a new study funded in part by NASA and the Canadian government has found.

Published Monday, the paper from researchers in Canada, the United States and Switzerland studied the downstream .

"Every single day has [a] slightly different length, because of so many factors, including 鈥 climate change," said study co-author Surendra Adhikari in an interview with CTVNews.ca.

"This is 鈥 a testament of the gravity of ongoing climate change."

The pale blue dot(-oid) 

The relationship between carbon emissions and our choreography in the cosmic ballet comes down to something most Earthlings take for granted: The planet's shape.

Contrary to popular belief, Planet Earth isn't actually a perfect sphere. While the surface of land around the world is remarkably smooth on the planetary scale, what most forget to consider is water; in particular, how that water moves.

As the planet spins on its axis, the distribution of Earth's oceans is impacted by that force, and like in a centrifuge, the liquid is pushed out from the centre, especially near the equator.

As a result, Earth, its oceans and all, bulges out at the middle, creating not a sphere, but a . That oblateness, or the size of the bulge at the equator, is central to Adhikari and co.'s findings.

In short, as rising global temperatures melt the polar ice caps, more of the Earth's water supply is converted to liquid, allowing it to swell the oblate bulge along the equator, when it might previously have stayed locked away in the ice.

The swelling, in turn, changes the dynamics of how Earth spins in the first place, and invariably, the rotation decelerates.

"If you see how a figure skater controls their motion 鈥 i, which is basically the same concept," Adhikari explained. "It has everything to do with the conservation of angular momentum."  

A matter of milliseconds

Though days are measured at a standardized length of 86,400 seconds each, the actual time it takes for a point on the Earth's surface to make a full rotation is getting ever-so-slightly longer, at a rate scientists say could get more severe as the perils of climate change deepen.

Relative to the age of the Earth, the 24-hour day is fairly new, a height reached after billions of years of growth. Five-hundred million years ago, ; another billion years back, and scientists estimate something closer to 19 hours.

Historically, the rate of increase attributable to climate change has been slow, hovering between 0.3 and one added daily millisecond each 100 years between 1900 and 2000. But as the industrial revolution's aftereffects have intensified, the rate has grown, clocking in at roughly 1.33 milliseconds per day, per century, since the turn of the millenium.

Adhikari and his colleagues' research found that in a high-emissions scenario, by 2100, it could surpass 2.5 milliseconds, marking the first time that humanity's influence on the Earth's spin would be greater than that of the Moon and the tides.

"Over the course of Earth鈥檚 geological evolution, tidal friction by the moon has been the dominant cause of the 鈥 increase in [length of day]," the study concludes.

"If, however, greenhouse gas emissions continue to rise, the increase in atmospheric and oceanic warming and associated ice melting will lead to a much higher rate 鈥 becoming the most important contribution to the long-term [length-of-day] variations." 

Time to get a new watch?

In practical terms, a few extra milliseconds per day over the course of a human lifetime isn't the most pressing impact of climate change, though Adhikari notes that computer systems, which rely on the 86,400-second day, may require an adjustment as the intricacies of time start to pass out of sync.

It's a problem that physicists and computer scientists alike have monitored since the 1970s, long understood to require to avoid widespread logistical headaches.

According to a recent study from the University of California San Diego, the impacts of climate change on the Earth's rotation might further complicate when and how those leap seconds need to be inserted; an additional piece of a vexing international puzzle.

"This will pose an unprecedented problem for computer network timing," the study reads. "."

Whether the Earth's spin brings on its own mini-Y2K any time soon, Adhikari says the NASA study's findings stand as a symbol for humanity's influence on our planet, that over the course of a few hundred years, the side effects of rapid, perhaps reckless industrialization may some day surpass those of the massive celestial body hanging in our night sky.

"In a way, we have messed up our climate system so much so that we are witnessing its impact on the very way our Earth spins,鈥 he said. "It's really profound."

CTVNews.ca Top Stories

Why brain aging can vary dramatically between people

Researchers are uncovering deeper insights into how the human brain ages and what factors may be tied to healthier cognitive aging, including exercising, avoiding tobacco, speaking a second language or even playing a musical instrument.

The union representing some 1,200 dockworkers at the Port of Montreal has overwhelmingly rejected a deal with their employers association.

A man who was critically injured in a police-involved shooting in Hamilton late Sunday afternoon has died in hospital, says the province鈥檚 police watchdog.

opinion

opinion How to transition from renting to owning a home in Canada

In his column for CTVNews.ca, personal finance contributor Christopher Liew offers a step-by-step guide on how to make the shift from renting to becoming a homeowner, and what you can start doing today to help the process go smoother.

Prime Minister Justin Trudeau announced voters in Cloverdale鈥擫angley City will pick their next member of Parliament on Dec. 16.

Local Spotlight

For the second year in a row, the 鈥楪ift-a-Family鈥 campaign is hoping to make the holidays happier for children and families in need throughout Barrie.

Some of the most prolific photographers behind CTV Skywatch Pics of the Day use the medium for fun, therapy, and connection.

A young family from Codroy Valley, N.L., is happy to be on land and resting with their newborn daughter, Miley, after an overwhelming, yet exciting experience at sea.

As Connor Nijsse prepared to remove some old drywall during his garage renovation, he feared the worst.

A group of women in Chester, N.S., has been busy on the weekends making quilts 鈥 not for themselves, but for those in need.

A Vancouver artist whose streetside singing led to a chance encounter with one of the world's biggest musicians is encouraging aspiring performers to try their hand at busking.

Ten-thousand hand-knit poppies were taken from the Sanctuary Arts Centre and displayed on the fence surrounding the Dartmouth Cenotaph on Monday.

A Vancouver man is saying goodbye to his nine-to-five and embarking on a road trip from the Canadian Arctic to Antarctica.