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Ice-free Arctic summers likely by 2050, even with climate action: study – The Independent Barents Observer

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By Levon Sevunts 

The study, Arctic Sea Ice in CMIP6,  published in Geophysical Research Letters analyzed recent results from 40 different climate models.

Using these models, scientists from 21 research institutes from around the world assessed the evolution of Arctic sea-ice cover in a scenario with high CO2 emissions and little climate protection.

As expected, summer Arctic sea-ice disappeared quickly in these simulations.

However, some of these models also showed that the ice still disappeared even in some simulations where CO2 emissions were rapidly reduced.

“The key point is that we have now reached a point that whether we are very aggressive in cutting our emissions or whether we go business as usual, we will be seeing years without any ice in the Arctic Ocean in the summer,” said study co-author Bruno Tremblay, associate professor in the Department of Atmospheric and Oceanic Sciences at McGill University.

What will change between different scenarios is the frequency at which this phenomenon occurs, Tremblay added.

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“If we go business as usual, it will be a much more frequent occurrence, it will be pretty much always the case starting in 2030, 2035 or 2040,” Trembleay told Radio Canada International in an interview from Toulouse, France, where he is on sabbatical.

“If we do severe cuts to our CO2 emissions, it will be an occurrence that happens once in a while but it will still occur.”

An ice-free Arctic 

Photo: Thomas Nilsen

Each summer, the area of sea-ice coverage decreases and grows again in winter.

However, since researchers began keeping satellite records in 1979, summer Arctic ice has lost 40 per cent of its area and up to 70 per cent of its volume.

The entire Arctic Ocean, the smallest and the shallowest of world oceans, covers an area of about 14.06 million square kilometres.

Scientists define an ice-free Arctic as one in which the Arctic Ocean sea ice covers an area of about 1 million square kilometres or less, Tremblay said.

“When you have 1 million square kilometres of ice left, you have a thin, narrow band of ice left in the north of the Canadian Arctic Archipelago and some ice left within the archipelago but basically the entire Arctic Ocean is free of ice except for that very localized region,” Tremblay said.

The ice-free season is also expected to get substantially longer, he added.

“Ice always comes back in the winter but it will come back later and later, because as you have less and less ice, more solar light is absorbed in the surface ocean, it takes longer in the fall before you ventilate all this heat into the atmosphere,” Tremblay said.

“And so gradually October becomes ice-free as well, August as well, not just September, and then November-December becomes ice-free and June as well, so the ice-free season becomes wider and wider.”

Affecting Arctic ecosystems 

Walruses on the ice in the Hinlopen Strait between Spitsbergen and Nordaustlandet on Svalbard. Photo: Thomas Nilsen

This will substantially affect the Arctic ecosystem and climate, particularly ice-dependent species such as polar bears and seals, Tremblay said.

“This will mean for them a longer and longer period without ice, which basically means fasting,” Tremblay said.

“For polar bears it means staying on land and they will have to wait until the end of October, November and then finally December before they can return and hunt [on the ice],” Tremblay said.

Female polar bears give birth to cubs in January and February and then go on the ice in May to hunt seals and fatten up until the ice-free season comes and they have to fast, he said.

With the ice-free season coming earlier and lasting longer, this means polar bears will have to fast for much longer.

Research in the Western Hudson Bay in the southern part of the Canadian Arctic shows that the average fasting time for polar bears in the area has gone from 107 days in the 1980s to 130 days in the early 2000s.

As a result, the Western Hudson Bay polar bear population is estimated to have dropped by 30 per cent since the 1980s. Other polar bear populations further north in the Canadian Arctic are stable or even growing. However, that could change with the warming climate.

“We’re seeing in the Hudson Bay now is what we will be seeing the Arctic Ocean in a decade or two,” Tremblay said.

The models looking even further into the future into 2100 and 2200 predict an ice free Arctic even in the winter, Tremblay said.

However, as the Arctic sea-ice extent decreases during this transition to an ice-free Arctic, the year-to-year variability in extent is expected to greatly increase, Tremblay said.

The last time the Earth experienced conditions like these was about 6,000 years ago at the end of the last glacial period when the solar insulation was much higher than it is now, Tremblay said.

“And what we’re going to see at the end of the century, you’re going to have to go back even further back, like hundreds of thousands of years, millions of years back when you saw conditions that warm,” Tremblay said.


This story is posted on Independent Barents Observer as part of Eye on the Arctic, a collaborative partnership between public and private circumpolar media organizations.

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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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