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Ancient soil once stored at UB shows Greenland melted recently … and could melt again

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A new study that analyzes ancient soil once stored at the University at Buffalo is causing a worrisome rethinking of the history of Greenland’s ice sheet and reveals its fragile nature today.

Joshua Brown, University of Vermont

Release Date: July 21, 2023

BUFFALO, N.Y. — Until recently, geologists believed that Greenland was a fortress of ice, mostly unmelted for millions of years. But, two years ago, using soil once buried a mile beneath the island’s ice sheet and later stored at the University at Buffalo, a team of scientists showed that it likely melted less than one million years ago.

Now, further analysis of the sediment has created a starker picture: Greenland was a green land only 416,000 years ago.

The team’s new study — published July 21 in the journal Science and co-authored by Elizabeth Thomas, associate professor of geology in the UB College of Arts and Sciences — presents direct evidence that the sediment was deposited by flowing water in an ice-free environment during a moderate warming period from 424,000 to 374,000 years ago.

“It’s really the first bulletproof evidence that much of the Greenland ice sheet vanished when it got warm,” says University of Vermont geoscientist Paul Bierman, who co-led the study with lead author Drew Christ, a postdoctoral geoscientist who worked in Bierman’s lab.

Elizabeth Thomas, Univeristy at Buffalo associate professor of geology, conducted chemical analysis that enabled the team to understand the types of plants that were on site. Credit: Douglas Levere/University at Buffalo

Understanding Greenland’s past is critical for predicting how its giant ice sheet will respond to climate warming in the future. The new study provides strong and precise evidence that Greenland is more sensitive to climate change than previously understood — and at grave risk of irreversibly melting off.

Since about 23 feet of sea level rise is tied up in Greenland’s ice, every coastal region in the world is at risk.

Under ice

Camp Century was a U.S. Army base on Greenland in the 1960s. It was the site of a secret operation, called Project Iceworm, to hide nuclear missiles under the ice near the Soviet Union.

The missile mission was a bust, but the science team did complete first-of-its-kind research, including drilling a nearly mile-deep ice core. The Camp Century scientists were focused on the ice itself, so they took little interest in the 12 feet of sediment gathered from beneath their ice core.

Engineers with the Cold Regions Research and Engineering Laboratory capture part of an ice core at Camp Century, Greenland, circa 1966. Credit: U.S. Army Corps of Engineers

Then, in a bizarre story, the ice core was moved in the 1970s from a military freezer to UB by then-UB geology professor, Chester “Chet” Langway, who was one of the leads of the Camp Century drilling expedition. He kept the ice core at a building on Ridge Lea Road in Amherst that housed UB’s Department of Geology while the North Campus was being built.

When retiring from UB in the 1990s, Langway gave the ice core to colleagues in Denmark. There it was lost for decades — until it was found again when the cores were being moved to a new freezer in 2017.

In 2019, Christ looked at the sediment through his microscope and found leaves and moss. That suggested that the area had been free of ice in the recent geologic past — and that a vegetated landscape stood where today stands an ice sheet two miles thick and three times the size of Texas.

The team, including Christ and UB’s Thomas, published their findings in 2021 in the Proceedings of the National Academy of Sciences.

Other scientists, working in central Greenland, have gathered data showing the ice there melted at least once in the last 1.1 million years — but no one knew exactly when.

Into the light

For this latest study, the team examined the Camp Century sediment for what is called a “luminescence signal.”

When bits of rock and sand are exposed to sunlight, any previous luminescence signal is zeroed out. When reburied in the darkness under rock or ice over time, minerals of quartz and feldspar in the sediment accumulate freed electrons in their crystals.

At the Utah State University lab of study co-author Tammy Rittenour, pieces of the ice core sediment were exposed to blue-green or infrared light, releasing the trapped electrons. The number of released electrons forms a kind of clock, revealing with precision the last time these sediments were exposed to the sun.

A sediment sample from the Camp Century core site. Credit: Drew Christ/University of Vermont

This powerful new data was combined with insight from Bierman’s University of Vermont lab, which studied the quartz from the Camp Century core. Ratios of beryllium and other isotopes inside the quartz – which build up when exposed to the sky and hit by cosmic rays — demonstrate how long rocks at the surface were exposed vs. buried under layers of ice.

This data helped the scientists show that, 400,000 years ago, the Camp Century sediment was exposed to the sky less than 14,000 years before it was deposited under the ice, narrowing down the time window when that portion of Greenland must have been ice-free.

Thomas conducted chemical analysis that enabled the team to understand the types of plants that were on site. The team is doing similar analyses to understand what the temperature and water cycle were like when those chemicals were produced.

Sea level

The team’s new study, combined with their earlier work, is causing a worrisome rethinking of the history of Greenland’s ice sheet and reveals its fragile nature today.

The last time the ice sheet melted, the team’s models show, it caused at least five feet of sea level rise. Temperatures during that time, an interglacial called Marine Isotope Stage 11, were similar to or slightly warmer than today, and atmospheric carbon dioxide was at least a third less than it is today.

“Forward modeling the rates of melt, and the response to high carbon dioxide, we are looking at meters of sea level rise, probably tens of meters,” Rittenour says. “And then look at the elevation of New York City, Boston, Miami, Amsterdam. Look at Bangladesh, India and Africa—most global population centers are near sea level.”

“Four-hundred-thousand years ago there were no cities on the coast,” Bierman adds, “and now there are cities on the coast.”

The research was supported by the National Science Foundation.

Media Contact Information

Tom Dinki
News Content Manager
Physical sciences, economic development
Tel: 716-645-4584
tfdinki@buffalo.edu

 

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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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