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A skinny robot documents the forces eroding a massive Antarctic glacier

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Scientists got their first up-close look at what’s eating away part of Antarctica’s Thwaites ice shelf, nicknamed the Doomsday Glacier because of its massive melt and sea rise potential, and it’s both good and bad news.

Using a 13-foot pencil-shaped robot that swam under the grounding line where ice first juts over the sea, scientists saw a shimmery critical point in Thwaites’ chaotic breakup, “where it’s melting so quickly there, there’s just material streaming out of the glacier,” said robot creator and polar scientist Britney Schmidt of Cornell University.

Before, scientists had no observations from this critical but hard-to-reach point on Thwaites. But with the robot named Icefin lowered down a slender 1,925-foot (587-meter) hole, they saw how important crevasses are in the fracturing of the ice, which takes the heaviest toll on the glacier, even more than melting. “That’s how the glacier is falling apart. It’s not thinning and going away. It shatters,” said Schmidt, lead author of one of two studies in Wednesday’s journal Nature.

That fracturing “potentially accelerates the overall demise of that ice shelf,” said Paul Cutler, the Thwaites program director for the National Science Foundation who returned from the ice last week. “It’s eventual mode of failure may be through falling apart.”

The work comes out of a massive $50 million multi-year international research effort to better understand the widest glacier in the world. The Florida-sized glacier has gotten the nickname the “Doomsday Glacier” because of how much ice it has and how much seas could rise if it all melts — more than 2 feet (65 centimeters), though that’s expected take hundreds of years.

The melting of Thwaites is dominated by what’s happening underneath, where warmer water nibbles at the bottom, something called basal melting, said Peter Davis, an oceanographer at British Antarctic Survey who is a lead author of one of the studies.

“Thwaites is a rapidly changing system, much more rapidly changing than when we started this work five years ago and even since we were in the field three years ago,” said Oregon State University ice researcher Erin Pettit, who wasn’t part of either study. “I am definitely expecting the rapid change to continue and accelerate over the next few years.”

Pennsylvania State University glaciologist Richard Alley, who also wasn’t part of the studies, said the new work “gives us an important look at processes affecting the crevasses that might eventually break and cause loss of much of the ice shelf.”

Dichek / AP

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AP

A robot nicknamed Icefin is deployed at Thwaites glacier in Antarctica in January 2020. Two studies published Wednesday, Feb. 15, 2023, show the rate of melting isn’t as fast as feared, but fracturing is taking the heaviest toll on the glacier.

The good news: Much of the flat underwater area they explored is melting much slower than they expected. The bad news: That doesn’t really change how much ice is coming off the land part of the glacier and driving up sea levels, Davis said.

Davis said the melting isn’t nearly the problem at Thwaites that glacier retreat is. The more the glacier breaks up or retreats, the more ice floats in water. When ice is on ground as part of the glacier it isn’t part of sea rise, but when it breaks off land and then goes onto water it adds to the overall water level by displacement, just as ice added to a glass of water raises water level.

And more bad news: This is from the eastern, larger and more stable part of Thwaites. Researchers couldn’t safely land a plane and drill a hole in the ice in the main trunk, which is breaking up much faster. And they also found staircase-like steps, those crevasses, in parts of the more stable eastern side where the break-up is far faster and worse.

The key to seeing exactly how bad conditions are on the glacier would require going to the main trunk and looking at the melting from below. But that would require a helicopter to land on the ice instead of a heavier airplane and would be incredibly difficult, said studies co-author Eric Rignot of the University of California Irvine.

The main trunk’s glacier surface “is so messed up by crevasses it looks like a set of sugar cubes almost. There’s no place to land a plane,” NSF’s Cutler said.

Ted Scambos of the National Snow and Ice Data Center, who wasn’t part of the studies, said the results add to understanding how Thwaites is diminishing.

“Unfortunately, this is still going to be a major issue a century from now,” Scambos said in an email. “But our better understanding gives us some time to take action to slow the pace of sea level rise.”

When the skinny robot wended its way through the hole in the ice – made by a jet of hot water – the cameras showed not just the melting water, the crucial crevasses and seabed. It showed critters, especially sea anemones, swimming under the ice.

“To accidentally find them here in this environment was really, really cool,” Schmidt said in an interview. “We were so tired that you kind of wonder like, ‘am I really seeing what I’m seeing?’ You know because there are these little creepy alien guys (the anemones) hanging out on the ice-ocean interface.

“In the background is like all these sparkling stars that are like rocks and sediment and things that were picked up from the glacier,” Schmidt said. “And then the anemones. It’s really kind of a wild experience.”

Copyright 2023 NPR. To see more, visit https://www.npr.org.

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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.

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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.”

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B.C. sets up a panel on bear deaths, will review conservation officer training

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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.

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