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.
“Every single day has [a] slightly different length, because of so many factors, including … climate change,” said study co-author Surendra Adhikari in an interview with CTVNews.ca.
“This is … 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 shape scientists refer to an oblate spheroid. 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 … if they have to slow down, they just extend their arms or legs, 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, a day-night cycle might have clocked just 22 hours in total; 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’s geological evolution, tidal friction by the moon has been the dominant cause of the … 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 … 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.
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.
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 in just a few hundred years of industrialization, the side effects may some day surpass those of the massive celestial body hanging in our night sky.
“It’s really profound,” he said. “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 … a tiny human being, who is doing some stupid things, and making this happen.”
NAIROBI, Kenya (AP) — The body of Ugandan Olympic athlete Rebecca Cheptegei — who died after being set on fire by her partner in Kenya — was received Friday by family and anti-femicide crusaders, ahead of her burial a day later.
Cheptegei’s family met with dozens of activists Friday who had marched to the Moi Teaching and Referral Hospital’s morgue in the western city of Eldoret while chanting anti-femicide slogans.
She is the fourth female athlete to have been killed by her partner in Kenya in yet another case of gender-based violence in recent years.
Viola Cheptoo, the founder of Tirop Angels – an organization that was formed in honor of athlete Agnes Tirop, who was stabbed to death in 2021, said stakeholders need to ensure this is the last death of an athlete due to gender-based violence.
“We are here to say that enough is enough, we are tired of burying our sisters due to GBV,” she said.
It was a somber mood at the morgue as athletes and family members viewed Cheptegei’s body which sustained 80% of burns after she was doused with gasoline by her partner Dickson Ndiema. Ndiema sustained 30% burns on his body and later succumbed.
Ndiema and Cheptegei were said to have quarreled over a piece of land that the athlete bought in Kenya, according to a report filed by the local chief.
Cheptegei competed in the women’s marathon at the Paris Olympics less than a month before the attack. She finished in 44th place.
Cheptegei’s father, Joseph, said that the body will make a brief stop at their home in the Endebess area before proceeding to Bukwo in eastern Uganda for a night vigil and burial on Saturday.
“We are in the final part of giving my daughter the last respect,” a visibly distraught Joseph said.
He told reporters last week that Ndiema was stalking and threatening Cheptegei and the family had informed police.
Four in 10 women or an estimated 41% of dating or married Kenyan women have experienced physical or sexual violence perpetrated by their current or most recent partner, according to the Kenya Demographic and Health Survey 2022.
TEL AVIV, Israel (AP) — A rare Bronze-Era jar accidentally smashed by a 4-year-old visiting a museum was back on display Wednesday after restoration experts were able to carefully piece the artifact back together.
Last month, a family from northern Israel was visiting the museum when their youngest son tipped over the jar, which smashed into pieces.
Alex Geller, the boy’s father, said his son — the youngest of three — is exceptionally curious, and that the moment he heard the crash, “please let that not be my child” was the first thought that raced through his head.
The jar has been on display at the Hecht Museum in Haifa for 35 years. It was one of the only containers of its size and from that period still complete when it was discovered.
The Bronze Age jar is one of many artifacts exhibited out in the open, part of the Hecht Museum’s vision of letting visitors explore history without glass barriers, said Inbal Rivlin, the director of the museum, which is associated with Haifa University in northern Israel.
It was likely used to hold wine or oil, and dates back to between 2200 and 1500 B.C.
Rivlin and the museum decided to turn the moment, which captured international attention, into a teaching moment, inviting the Geller family back for a special visit and hands-on activity to illustrate the restoration process.
Rivlin added that the incident provided a welcome distraction from the ongoing war in Gaza. “Well, he’s just a kid. So I think that somehow it touches the heart of the people in Israel and around the world,“ said Rivlin.
Roee Shafir, a restoration expert at the museum, said the repairs would be fairly simple, as the pieces were from a single, complete jar. Archaeologists often face the more daunting task of sifting through piles of shards from multiple objects and trying to piece them together.
Experts used 3D technology, hi-resolution videos, and special glue to painstakingly reconstruct the large jar.
Less than two weeks after it broke, the jar went back on display at the museum. The gluing process left small hairline cracks, and a few pieces are missing, but the jar’s impressive size remains.
The only noticeable difference in the exhibit was a new sign reading “please don’t touch.”
VICTORIA – The British Columbia government is partnering with a bear welfare group to reduce the number of bears being euthanized in the province.
Nicholas Scapillati, executive director of Grizzly Bear Foundation, said Monday that it comes after months-long discussions with the province on how to protect bears, with the goal to give the animals a “better and second chance at life in the wild.”
Scapillati said what’s exciting about the project is that the government is open to working with outside experts and the public.
“So, they’ll be working through Indigenous knowledge and scientific understanding, bringing in the latest techniques and training expertise from leading experts,” he said in an interview.
B.C. government data show conservation officers destroyed 603 black bears and 23 grizzly bears in 2023, while 154 black bears were killed by officers in the first six months of this year.
Scapillati said the group will publish a report with recommendations by next spring, while an independent oversight committee will be set up to review all bear encounters with conservation officers to provide advice to the government.
Environment Minister George Heyman said in a statement that they are looking for new ways to ensure conservation officers “have the trust of the communities they serve,” and the panel will make recommendations to enhance officer training and improve policies.
Lesley Fox, with the wildlife protection group The Fur-Bearers, said they’ve been calling for such a committee for decades.
“This move demonstrates the government is listening,” said Fox. “I suspect, because of the impending election, their listening skills are potentially a little sharper than they normally are.”
Fox said the partnership came from “a place of long frustration” as provincial conservation officers kill more than 500 black bears every year on average, and the public is “no longer tolerating this kind of approach.”
“I think that the conservation officer service and the B.C. government are aware they need to change, and certainly the public has been asking for it,” said Fox.
Fox said there’s a lot of optimism about the new partnership, but, as with any government, there will likely be a lot of red tape to get through.
“I think speed is going to be important, whether or not the committee has the ability to make change and make change relatively quickly without having to study an issue to death, ” said Fox.
This report by The Canadian Press was first published Sept. 9, 2024.
