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Greenland and Antarctica are Losing Their Ice 6 Times Faster than in the 1990s – Universe Today

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Is anybody listening?

Smart people tell us that when it comes to conveying the reality of climate change, and the threat it poses, people don’t respond to facts. We respond to stories and narratives. We’re a narrative-driven species.

But at Universe Today we know that facts underlie every good story. And the facts regarding ice loss in Greenland and Antarctica are not good.

“Every centimetre of sea level rise leads to coastal flooding and coastal erosion, disrupting people’s lives around the planet.”

Prof. ANdrew Shepherd, University of Leeds, IMBIE

These latest findings, showing that both Greenland and Antarctica are losing their ice six times faster than in the 1990s, were published in the journal Nature. Unfortunately, but not necessarily surprisingly, these results are in line with the IPCC’s (International Panel on Climate Change) worst-case scenario predictions.

One of the papers is titled “Mass balance of the Greenland Ice Sheet from 1992 to 2018.” It gives author credit to ‘The IMBIE Team.’ IMBIE is the Ice Sheet Mass Balance Inter-comparison Exercise. Andrew Shepherd from the University of Leeds and Erik Ivins at NASA’s Jet Propulsion Laboratory lead IMBIE.

IMBIE is an international collaboration of polar scientists, with both NASA and the European Space Agency playing leading roles. In their latest release, they start by looking at the recent past. Between 1992 and 2017, Greenland and Antarctica lost a combined total of 6.4 trillion tons of ice. That pushed sea levels up by 17.8 millimeters.

Rate of elevation change of the Greenland Ice Sheet determined from ERS, ENVISAT and CryoSat-2 satellite radar altimetry (top row) and from the HIRHAM5 SMB model (ice equivalent; bottom row) over successive 5-yr epochs. Image Credit: The IMBIE Team, 2020.

Antarctic ice melting accounted for about 60% of the rise, or 10.6 mm. Greenland’s melting accounted for the remainder.

In only three decades, melting has increased six-fold. That’s from roughly 81 billion tons per year in the 1990s to 475 billion tons per year in the 2010s. This the conclusion: The melting of our polar ice sheets contributed one-third of all sea level rise in that time-frame.

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The data behind these conclusions comes from a total of 11 satellites. The 11 includes the EU’s (European Union) Copernicus Sentinel-1 and Sentinel-2 missions, as well as the ESA’s Envisat and CryoSat missions.

The scientific term for the large-scale loss of ice in the polar sheets is ‘mass balance.’ It’s like an equation with ice on one side and sea levels on the other. And right now, one side of that equation growing, at the expense of the other. Prof. Shepherd explains, “Every centimetre of sea level rise leads to coastal flooding and coastal erosion, disrupting people’s lives around the planet.”

“If Antarctica and Greenland continue to track the worst-case climate warming scenario, they will cause an extra 17 centimetres of sea level rise by the end of the century,” said Shepherd. “This would mean 400 million people are at risk at annual coastal flooding by 2100. These are not unlikely events with small impacts; they are already underway and will be devastating for coastal communities.”

So, what are we going to do? Hoard toilet paper?

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For scientists, the mission is clear: keep working cooperatively to gather data and keep presenting it clearly. And satellites play a huge role in monitoring the planet’s melting ice sheets.

ESA’s Director of Earth Observation Programmes, Josef Aschbacher, comments, “The findings reported by IMBIE demonstrate the fundamental importance of using satellite data to monitor the evolution of ice sheets. IMBIE is also a prime example of how the best science teams in Europe and the US have worked in an exemplary way together to address some burning questions of science.”

The International Panel on Climate Change was created by the United Nations way back in 1988. Its role is to gather the data on climate change and present reports, specifically to policy-makes in the UN’s member nations. This new release from IMBIE confirms the IPCC’s worst-case scenario: global sea levels will rise 60 centimetres by the year 2100.

In fact, this new IMBIE report exceeds the IPCC’s worst-case scenario. Emissions are rising faster than expected, not falling at all, and melting has increased since observations began.

Guðfinna Aðalgeirsdóttir, Professor of Glaciology at the University of Iceland and lead author of the Intergovernmental Panel on Climate Change’s sixth assessment report, commented, “The IMBIE Team’s reconciled estimate of Greenland and Antarctic ice loss is timely for the IPCC. Their satellite observations show that both melting and ice discharge from Greenland have increased since observations started.”

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The amount of ice lost during each year can fluctuate. Sometimes, a single year will have less ice loss than the trend, and optimism briefly blooms. But the trend is consistent, and though Antarctica and Greenland host the two largest sheets, other ice sheets around the world are also under scientific scrutiny.

“The ice caps in Iceland had similar reduction in ice loss in the last two years of their record, but summer 2019 was very warm in this region which resulted in higher mass loss,” Aðalgeirsdóttir said in a press release. “I would expect a similar increase in Greenland mass loss for 2019. It is very important to keep monitoring the big ice sheets to know how much they raise sea level every year.”

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Antarctica and Greenland experience melting in different ways. In Antarctica, almost all of the ice loss is due to the warming oceans. As the outlet glaciers reach the ocean, they’re melting more quickly, causing them to speed up. It’s like conveyor belt of ice, and our emissions are the throttle.

The largest glacier in Antarctica is the Lambert Glacier. It’s also one of the largest in the world, with a length of over 400 km and an area of 1 million square km. It feeds into the Amery Ice Shelf, which is where the glacier leaves underlying land and floats on the water.

Antarctica's Lambert Glacier is one of the largest in the world. Image Credit: National Snow and Ice Data Center.
Antarctica’s Lambert Glacier is one of the largest in the world. Image Credit: National Snow and Ice Data Center.

The warming ocean is eating away at the Amery Ice Shelf, making it melt faster and making the Lambert Glacier travel faster. The rate of travel has been monitored by satellite, and those observations clearly show the glacier speeding up at the ocean.

This NASA image shows glacier velocities. Brown=50m per year, Green=250m, Blue=500m, Purple=1000m, and Red=up to 1200m per year. Image Credit: NASA, Public Domain, https://commons.wikimedia.org/w/index.php?curid=52852432
This NASA image shows glacier velocities. Brown=50m per year, Green=250m, Blue=500m, Purple=1000m, and Red=up to 1200m per year. Image Credit: NASA, Public Domain, https://commons.wikimedia.org/w/index.php?curid=52852432

Greenland suffers ice loss through contact with the ocean too, but that accounts for only about half of its ice loss. The other half is due to warmer air.

We all know that our emissions are behind this. It doesn’t matter what political outlook you subscribe to. Science tells us what’s happening, and the evidence is overwhelming. This report is just one more piece.

Cool story, huh?

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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 Seth Borenstein on Twitter at @borenbears

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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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