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Scientists warn critical ice shelf in Antarctica could shatter within 5 years – CTV News

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As the rapidly heating planet alters the landscape of the Arctic region up north, scientists have discovered disturbing and alarming signs at the southern end of the planet, particularly in one of the ice shelves safeguarding the Antarctic’s so-called “Doomsday glacier.”

Satellite images taken as recently as last month, which researchers presented at the annual meeting of the American Geophysical Union Monday, suggest the critical ice shelf keeping together the Thwaites glacier in western Antarctica — an important defence against global sea level rise — could shatter within the next three to five years.

Antarctica’s Thwaites glacier is known as the “Doomsday glacier,” due to the serious risk it poses during its melting process. It has dumped billions of tons of ice into the sea, and its demise could lead to irreversible changes throughout the planet.

The glacier, which equals the size of Florida or Great Britain, already accounts for about 4% of annual global sea level rise, loses roughly 50 billion tons of ice each year, and is becoming highly vulnerable to the climate crisis. The fall of the ice shelf could bring the impending collapse of Antarctica’s critical glacier.

If the Thwaites collapsed, the event could raise sea levels by several feet, researchers say, putting coastal communities as well as low-lying island nations further at risk.

But Ted Scambos, a glaciologist at the University of Colorado Boulder, and a leader of the International Thwaites Glacier Collaboration, said it will still be decades before the world will see real acceleration and an additional uptick in sea level rise.

“What is attention-getting about Thwaites is that the change will proceed with fairly dramatic, measurable results within the next few decades,” Scambos told CNN.

For now, the glacier is being held back by a critical floating ice shelf.

“What’s most concerning about the recent results is that it’s pointing to a collapse of this ice shelf, this kind of safety band that holds the ice on the land,” Peter Davis, oceanographer with the British Antarctic Survey, told CNN. “If we lose this ice shelf, then the glacier will flow into the ocean more quickly, contributing towards sea level rise.”

Warming ocean waters play a key role in driving the rapid deterioration. A 2020 study by the International Thwaites Glacier Collaboration, which is currently leading ongoing research in the Antarctic, found the ocean floor is deeper than scientists previously thought, with deep passages allowing warm ocean water to melt the underside of the ice.

The observations show the critical ice shelf keeping the Thwaites together is loosening its grip on the underwater mountain, or the seamount, which acts as a reinforcement against the ice river from flowing into the warm ocean. Researchers also found the so-called “ice tongue” of the Thwaites Glacier is simply now a “loose cluster of icebergs,” which no longer influences the stable part of the eastern ice shelf.

Warm water also threatens the so-called “grounding zone,” where the ice meets the seabed. Davis and his team used hot water to drill access holes from the surface of the ice shelf and deep into the ocean cavity underneath. In doing so, they discovered not only are the ocean waters in the grounding line warm, by polar standards, but it is also salty, priming the landscape for further erosion.

Peter Washam, a research associate at Cornell University, who is also involved with the research, said the physical features of the grounding zone shows signs of chaos, such as warm water, rugged ice, and a steep, sloping bottom that allows the water to rapidly melt the ice sheet from below.

“In the coming years, we expect the Thwaites grounding line in the region to slowly retreat up the seabed slope that it currently rests on as the warm ocean eats away at its underside,” Washam told CNN. His team used an underwater vehicle called Icefin that makes it easier to study ice and water around and beneath ice shelves.

The bottom line, according to Davis, is Antarctica’s Thwaites Glacier is rapidly deteriorating. The warm ocean water is slowly erasing the ice underneath, causing water to flow faster, fracturing more of the ice, and bringing the looming threat of a collapse even closer.

“From the satellite data, we’re seeing these big fractures spreading across the ice shelf surface, essentially weakening the fabric of the ice; kind of a bit like a windscreen crack,” he said. “It’s slowly spreading across the ice shelf and eventually it’s going to fracture into lots of different pieces.”

Scambos said while the process is extremely slow-moving and real impacts won’t be felt until several decades later, it is nearly impossible to stop it.

“This is a geologic process, but happening at almost a human-lifetime scale,” he said. “As a disaster for people alive today, it is extremely slow-moving. The best path is to try to slow the forces that are pushing the ice in this direction.”

And as the ramifications of the climate crisis spread around the globe, the researchers say expanding scientific research to understand changes in both the Arctic and Antarctic regions is critical to planning mitigation strategies such as coastal defences in vulnerable communities.

“We can’t really do anything to stop this from happening,” besides slowing it down, Davis said. “The way that we’ve gone with our carbon emissions so far has caused these changes to occur — and essentially, we’re taking the consequences of what we’ve been emitting over the last couple of decades, if not longer.”

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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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