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Climate tipping points are difficult to predict. In Canada and beyond, they might have already arrived – CBC.ca

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Scientists have been watching extreme weather events unfold all over the world this summer, seeing the many links between heatwaves, floods, droughts and climate change. 

But the scale of some of these events, and just how dramatically they have upended previous records, suggests that the climate is no longer changing in a gradual, predictable way.

Deadly heat waves and other wild weather are putting renewed attention on tipping points  — the idea that major shifts to key ecosystems, such as Greenland’s ice sheets or the Amazon rainforest, can cause large, irreversible changes to the planet’s climate balance. 

“Tipping points are large-scale changes that could happen abruptly and could be potentially irreversible,” said Owen Gaffney, an analyst at the Stockholm Resilience Centre, a research institute

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He co-authored a 2019 article in the journal Nature that listed nine tipping points around the world that scientists are watching with growing concern. A prime example is the ice-sheets in parts of Antarctica and Greenland. Rather than gradually shrinking as the climate warms, research suggests the sheets could hit points of no return leading to rapid and irreversible ice loss  — and a corresponding rise in global sea levels.

In Greenland, models suggest the “ice sheet could be doomed at 1.5 C of warming, which could happen as soon as 2030,” the report said.

In Canada, the trends are worrying. This summer, various parts of British Columbia saw temperature records broken during the heatwave in June, notably the town of Lytton, which set the record for the hottest temperature ever recorded in Canada at 49.6 C — a remarkable 5.2 C increase over Lytton’s previous heat record (which was also a record for B.C.) in 1941.

Lytton, B.C., set Canada’s hottest temperature record this summer, and was mostly destroyed by a wildfire afterwards. The new record was about five degrees above the town’s previous record. (Darryl Dyck/The Canadian Press)

“The analogy that scientists used to use is that as you warm the climate, it is like loading a pair of dice. And so now when you roll the dice, you get more sixes than you would have before,” said Simon Donner, a professor at the University of British Columbia who studies climate science and public policy. 

“But what we’ve been seeing this summer isn’t a six, it’s like a seven or eight, something that wasn’t possible with the old dice.”

Simon Donner is a climate science and public policy researcher at the University of British Columbia. (Don Erhardt)

A study examining how much of the heatwave on the west coast could be attributed to human-caused climate change by a group of international scientists suggested that one explanation for the high temperatures could be “​​nonlinear interactions in the climate.”

Rather than gradual increases in temperature extremes, this theory suggests that the present amount of climate change is causing bigger-than-expected increases in extreme heat due to interactions in the climate system that are not fully understood.

And that raises questions about what cities and communities need to do to adapt to a future climate that looks increasingly uncertain. 

Tipping points may have been already reached

An international group of climate scientists are now warning that there is “mounting evidence that we are nearing or have already crossed tipping points associated with critical parts of the Earth system.” In a paper published in the journal BioScience on July 28, researchers pointed to the West Antarctic and Greenland ice sheets, warm-water coral reefs, and the Amazon rainforest as climate systems that were possibly nearing or had already reached their tipping point.

The paper tracked 31 key climate variables, such as global emissions and tree cover loss and found that 18 are at all-time records. That includes the three important greenhouse gases, carbon dioxide, methane and nitrous oxide, which reached new records for atmospheric concentrations in both 2020 and 2021.

Given the impacts we are seeing at roughly 1.25 C of global warming, “combined with the many reinforcing feedback loops and potential tipping points, massive-scale climate action is urgently needed,” the paper said.

Trucks carry relief supplies in central China’s Henan Province, hit by flooding in July due to unprecedented rain. Climate change will make floods more severe in many parts of the world. (Dake Kang/The Associated Press)

Paul Ritchie, a mathematician and climate scientist at the University of Exeter in the U.K., researches where those tipping points lie and how far we can overshoot some of them while still being able to recover. Certain changes, such as the loss of ice sheets, have a relatively long timescale, Ritchie said, occurring over many centuries.

“But then there are these other elements… where these can happen over much shorter timescales, maybe years or decades,” he said. 

“So pretty much as soon as we go over these particular thresholds, we might instantly know because we have this sudden loss of the Amazon rainforest or the monsoon suddenly stops operating.”

Both events would have devastating consequences. Millions of people rely on the monsoons for agriculture, while the Amazon’s loss could release even more carbon and accelerate global warming.

Adaptation still possible, but Canada not there yet

Canada announced a plan to develop a national adaptation strategy in December 2020. But experts warn the country is not ready for the climate we have now, and needs to move fast to respond to the future.

“The reality is that we should assume that we’re not going to meet that [Paris Agreement] target of 2 C,” said Gordon McBean, a professor at the Western University in London, Ont., of the global deal to reduce carbon emissions to stop the worst impacts of climate change. 

McBean was the lead investigator on a report for the federal government earlier this year on building community resilience to climate change.

His report found that while many cities have high level plans to address climate change, others still lack detailed implementation strategies or funding. 

“Most actions to build community resilience in Canada are unplanned and take place in recovery following an extreme loss event,” the report said.

Government workers check an area consumed by fire in the Amazon rainforest in Brazil in 2020. The Amazon is one system that could be nearing a tipping point. (Andre Penner/The Associated Press)

As average temperatures rise in linearly fashion, the number of extreme weather events increases more dramatically, McBean said. “An adaptation strategy has to take into account not just future projections of weather, but also future projections of greenhouse gas emissions, and the chance that the rest of the world will not meet its emissions reduction goals.”

Recent heat domes and tornados are examples of the kinds of events that will happen more often in the future, he said.

With the climate set to continue to change for years to come, and new information coming out about the dangers of tipping points that could lead to extreme weather that’s unforeseen, adaptation has become more urgent.

McBean said there’s enough information available now to start planning for that uncertain future, and make communities more resilient.

“It’s not saying we failed. It’s saying here’s what we need to do,” he said.

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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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