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Days are getting longer because of climate change, according to NASA

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Ever New Canada

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 effects of climate change on the very physics of the planet itself.

“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.

It’s a problem that physicists and computer scientists alike have monitored since the 1970s, long understood to require occasionally shoehorning an extra “leap second” into counts by atomic clocks 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. “Global warming is already affecting global timekeeping.”

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.”

 

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Here’s how Helene and other storms dumped a whopping 40 trillion gallons of rain on the South

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More than 40 trillion gallons of rain drenched the Southeast United States in the last week from Hurricane Helene and a run-of-the-mill rainstorm that sloshed in ahead of it — an unheard of amount of water that has stunned experts.

That’s enough to fill the Dallas Cowboys’ stadium 51,000 times, or Lake Tahoe just once. If it was concentrated just on the state of North Carolina that much water would be 3.5 feet deep (more than 1 meter). It’s enough to fill more than 60 million Olympic-size swimming pools.

“That’s an astronomical amount of precipitation,” said Ed Clark, head of the National Oceanic and Atmospheric Administration’s National Water Center in Tuscaloosa, Alabama. “I have not seen something in my 25 years of working at the weather service that is this geographically large of an extent and the sheer volume of water that fell from the sky.”

The flood damage from the rain is apocalyptic, meteorologists said. More than 100 people are dead, according to officials.

Private meteorologist Ryan Maue, a former NOAA chief scientist, calculated the amount of rain, using precipitation measurements made in 2.5-mile-by-2.5 mile grids as measured by satellites and ground observations. He came up with 40 trillion gallons through Sunday for the eastern United States, with 20 trillion gallons of that hitting just Georgia, Tennessee, the Carolinas and Florida from Hurricane Helene.

Clark did the calculations independently and said the 40 trillion gallon figure (151 trillion liters) is about right and, if anything, conservative. Maue said maybe 1 to 2 trillion more gallons of rain had fallen, much if it in Virginia, since his calculations.

Clark, who spends much of his work on issues of shrinking western water supplies, said to put the amount of rain in perspective, it’s more than twice the combined amount of water stored by two key Colorado River basin reservoirs: Lake Powell and Lake Mead.

Several meteorologists said this was a combination of two, maybe three storm systems. Before Helene struck, rain had fallen heavily for days because a low pressure system had “cut off” from the jet stream — which moves weather systems along west to east — and stalled over the Southeast. That funneled plenty of warm water from the Gulf of Mexico. And a storm that fell just short of named status parked along North Carolina’s Atlantic coast, dumping as much as 20 inches of rain, said North Carolina state climatologist Kathie Dello.

Then add Helene, one of the largest storms in the last couple decades and one that held plenty of rain because it was young and moved fast before it hit the Appalachians, said University of Albany hurricane expert Kristen Corbosiero.

“It was not just a perfect storm, but it was a combination of multiple storms that that led to the enormous amount of rain,” Maue said. “That collected at high elevation, we’re talking 3,000 to 6000 feet. And when you drop trillions of gallons on a mountain, that has to go down.”

The fact that these storms hit the mountains made everything worse, and not just because of runoff. The interaction between the mountains and the storm systems wrings more moisture out of the air, Clark, Maue and Corbosiero said.

North Carolina weather officials said their top measurement total was 31.33 inches in the tiny town of Busick. Mount Mitchell also got more than 2 feet of rainfall.

Before 2017’s Hurricane Harvey, “I said to our colleagues, you know, I never thought in my career that we would measure rainfall in feet,” Clark said. “And after Harvey, Florence, the more isolated events in eastern Kentucky, portions of South Dakota. We’re seeing events year in and year out where we are measuring rainfall in feet.”

Storms are getting wetter as the climate change s, said Corbosiero and Dello. A basic law of physics says the air holds nearly 4% more moisture for every degree Fahrenheit warmer (7% for every degree Celsius) and the world has warmed more than 2 degrees (1.2 degrees Celsius) since pre-industrial times.

Corbosiero said meteorologists are vigorously debating how much of Helene is due to worsening climate change and how much is random.

For Dello, the “fingerprints of climate change” were clear.

“We’ve seen tropical storm impacts in western North Carolina. But these storms are wetter and these storms are warmer. And there would have been a time when a tropical storm would have been heading toward North Carolina and would have caused some rain and some damage, but not apocalyptic destruction. ”

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Follow AP’s climate coverage at https://apnews.com/hub/climate

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Follow Seth Borenstein on Twitter at @borenbears

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Associated Press climate and environmental coverage receives support from several private foundations. See more about AP’s climate initiative here. The AP is solely responsible for all content.

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‘Big Sam’: Paleontologists unearth giant skull of Pachyrhinosaurus in Alberta

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It’s a dinosaur that roamed Alberta’s badlands more than 70 million years ago, sporting a big, bumpy, bony head the size of a baby elephant.

On Wednesday, paleontologists near Grande Prairie pulled its 272-kilogram skull from the ground.

They call it “Big Sam.”

The adult Pachyrhinosaurus is the second plant-eating dinosaur to be unearthed from a dense bonebed belonging to a herd that died together on the edge of a valley that now sits 450 kilometres northwest of Edmonton.

It didn’t die alone.

“We have hundreds of juvenile bones in the bonebed, so we know that there are many babies and some adults among all of the big adults,” Emily Bamforth, a paleontologist with the nearby Philip J. Currie Dinosaur Museum, said in an interview on the way to the dig site.

She described the horned Pachyrhinosaurus as “the smaller, older cousin of the triceratops.”

“This species of dinosaur is endemic to the Grand Prairie area, so it’s found here and nowhere else in the world. They are … kind of about the size of an Indian elephant and a rhino,” she added.

The head alone, she said, is about the size of a baby elephant.

The discovery was a long time coming.

The bonebed was first discovered by a high school teacher out for a walk about 50 years ago. It took the teacher a decade to get anyone from southern Alberta to come to take a look.

“At the time, sort of in the ’70s and ’80s, paleontology in northern Alberta was virtually unknown,” said Bamforth.

When paleontogists eventually got to the site, Bamforth said, they learned “it’s actually one of the densest dinosaur bonebeds in North America.”

“It contains about 100 to 300 bones per square metre,” she said.

Paleontologists have been at the site sporadically ever since, combing through bones belonging to turtles, dinosaurs and lizards. Sixteen years ago, they discovered a large skull of an approximately 30-year-old Pachyrhinosaurus, which is now at the museum.

About a year ago, they found the second adult: Big Sam.

Bamforth said both dinosaurs are believed to have been the elders in the herd.

“Their distinguishing feature is that, instead of having a horn on their nose like a triceratops, they had this big, bony bump called a boss. And they have big, bony bumps over their eyes as well,” she said.

“It makes them look a little strange. It’s the one dinosaur that if you find it, it’s the only possible thing it can be.”

The genders of the two adults are unknown.

Bamforth said the extraction was difficult because Big Sam was intertwined in a cluster of about 300 other bones.

The skull was found upside down, “as if the animal was lying on its back,” but was well preserved, she said.

She said the excavation process involved putting plaster on the skull and wooden planks around if for stability. From there, it was lifted out — very carefully — with a crane, and was to be shipped on a trolley to the museum for study.

“I have extracted skulls in the past. This is probably the biggest one I’ve ever done though,” said Bamforth.

“It’s pretty exciting.”

This report by The Canadian Press was first published Sept. 25, 2024.

The Canadian Press. All rights reserved.

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The ancient jar smashed by a 4-year-old is back on display at an Israeli museum after repair

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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.”

The Canadian Press. All rights reserved.

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