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Climate change: The ice we’ve lost this decade, visualized – Vox.com

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One of the most poignant climate moments of 2019 was a funeral for ice: an August ceremony in Iceland for the country’s Okjökull glacier. As can be seen in these NASA satellite images, the glacier declined dramatically between 1986 and 2019:

The Ok glacier in Iceland lost its designation as a glacier in 2014 and was mourned over the summer this year.
Nasa Earth Observatory and NASA Earth Observatory

Mourners remembered the once-large patch of ice with a plaque.

“In the next 200 years all our glaciers are expected to follow the same path,” the plaque reads. “This monument is to acknowledge that we know what is happening and what needs to be done. Only you will know if we did it.”

The loss of Okjökull (officially stripped of its glacier status in 2014) was one of many deeply troubling milestones this decade in the world’s frozen regions, known collectively as the cryosphere. The Arctic in particular is warming twice as fast as the global average and experienced many historic heat waves. The warming, in turn, is causing an unprecedented amount of melt in the world’s ice.

The ice sheets on land have critical effects on seawater levels around the world. If all the ice on Greenland were to melt, it would raise global sea levels by 20 feet. If all the ice in Antarctica melted, it would raise sea levels by 190 feet.

That’s just for ice on land. The melt of once-frozen waters is threatening vulnerable species, changing circulation patterns in the ocean, and fueling feedback loops that could cause even more ice to melt.

In this post, we’ll walk through some of the key markers of climate change in the polar regions this decade with visuals, as well as some of the key insights we gained. (We’ve omitted Greenland’s ice sheet only because there aren’t many good images available.) We learned that ice is declining at both poles at an accelerating rate the world hasn’t seen in centuries. We can now see these dramatic changes from space. And we have a much better grasp on what we’ll lose if we don’t slow the emissions destabilizing the global climate.

There are two main categories of ice in the cryosphere. One is the ice that forms on land from precipitation: Two-thirds of the planet’s freshwater is frozen in these ice caps, sheets, and glaciers. The other is the ice that forms from freezing the ocean, known as sea ice.

The extent of sea ice tends to ebb and flow with the seasons, but over the past decade, both the highs and lows have gotten lower.

“If you look at just the last decade, 2010 to 2019, eight out of those 10 years are among the lowest 10,” said Walt Meier, a senior research scientist at the National Snow and Ice Data Center.

You can see that in this graph comparing the extent of Arctic sea ice over the course of a year. It grows in the winter and shrinks in the summer, but in recent years, there’s less of the former and more of the latter.

Christina Animashaun/Vox

The record low was in 2012, but this year isn’t much farther behind. “It’s kind of reinforcing that we’re heading on a downward trend,” Meier said.

But the picture is more bleak when we zoom out to a longer time scale: We are currently in the midst of the fastest decline of Arctic sea ice in 1,500 years.

Christina Animashaun/Vox

And you can see how this has played out in recent decades in this time lapse animation of ice at the North Pole:

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But Meier notes that it’s not just the extent of sea ice that’s changing; the thickness is shrinking as well. It’s a key factor in how much ice survives the summer and how quickly it can regrow in the winter, and we’ve only recently gained a good handle on this with new satellite instruments that can track thickness over time. “The thickness is decreasing as rapidly or more rapidly than the extent,” he said.

The planet’s South Pole is one of its coldest regions, and it’s warming up as well, prompting the rate of ice melt to accelerate. In the past decade, the rate of ice melt in Antarctica tripled compared to 2007. This is on pace to cause six inches of sea level rise by 2100.

Melting ice in Antarctica

Ice melt in Antarctica has accelerated in the past decade.
Javier Zarracina/Vox

You can see some of these dramatic changes playing out in sections of Antarctica, like the Pine Island Glacier. Here is an animation showing the retreat of the glacier since 2000.

The decline of Antarctica’s Pine Island Glacier since 2000.
The decline of Antarctica’s Pine Island Glacier since 2000.

The decline of Antarctica’s Pine Island Glacier since 2000.
NASA Earth Observatory

The trends in ice in Antarctica are a bit more complicated. There are sections of the Antarctic ice sheet where ice is growing in depth, and others where it is declining, as can be seen in this NASA visual looking at the last 25 years:

[embedded content]

Currently, the East Antarctic Ice Sheet, the larger, thicker, cooler, more stable sheet in Antarctica, is unlikely to see major changes in the coming years. But the West Antarctic Ice Sheet is showing signs of an accelerating rate of melt, driven in part by climate change.

Greenhouse gas emissions, meanwhile, climbed ever higher this decade. In 2010, carbon dioxide concentrations peaked at 394 parts per million (ppm), according to observations at the Mauna Loa Observatory. This year, the observatory reported a record high of 414.8 ppm, a concentration not seen on Earth for millions of years.

“At our current rates of increasing emissions, it’s pretty inevitable we’re going to have ice-free summer conditions at some point in the future, probably within the next, three decades,” Meier said. “It’s a matter of ‘when,’ not ‘if’ anymore.”

However, there is uncertainty in how many summers we’ll see without ice in the Arctic, and a key source of that uncertainty is what we’ll do about our greenhouse gas emissions.

The Paris climate agreement set out to limit warming this century to less than 2 degrees Celsius above pre-industrial levels, with a more ambitious target of staying below 1.5 degrees Celsius. Hitting the latter target would require halving global emissions by as soon as 2030, reaching net-zero emissions by 2050, and then net reductions of carbon dioxide in the atmosphere thereafter.

It’s a tall order, but reaching the more-ambitious goal would mean more ice would survive the summer. “In 2 degrees [Celsius] of warming, which is the target set in Paris, it’s likely that we’ll have ice-free summers pretty regularly under those conditions,” Meier said. “But if we hold things to 1.5 degrees [Celsius], which is kind of the ambitious goal, I’m not sure how realistic that is, we’ll likely keep a fair amount of ice around the summer.”

So we’ll likely lose even more from the coldest parts of the world in the coming decade. But the actions we all take will shape just how much is lost.

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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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