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Arctic warming: are record temperatures and fires arriving earlier than scientists predicted? – The Conversation UK

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It was a grim record. On June 20 2020, the mercury reached 38°C in Verkhoyansk, Siberia – the hottest it’s ever been in the Arctic in recorded history. With the heatwaves came fire, and by the start of August around 600 individual fires were being detected every day. By early September, parts of the Siberian Arctic had been burning since the second week of June.

CO₂ emissions from these fires increased by more than a third compared to 2019, according to scientists at the Copernicus Atmosphere Monitoring Service. The wildfires produced an estimated 244 megatons of CO₂ between January and August, releasing thousands of years’ worth of stored carbon.

The summer of 2019 was already a record breaker for temperatures and fires across the Arctic. Seeing these events unfold again in 2020 – on an even larger scale – has the scientific community worried. What does it all mean for the Arctic, climate change and the rest of the world?

A blanket of smoke stretches more than 4.5 million square kilometres across central and northern Asia. July 24 2019.
EPA-EFE/NASA EARTH OBSERVATORY

Sooner than predicted?

Even with climate change, the severe summer heatwave of 2020 was expected to occur, on average, less than once every 130 years. Wildfire observations in the Arctic are fairly limited prior to the mid-1990s, but there is no evidence of similarly extreme fires in the years before routine monitoring started.

Higher temperatures globally are likely to be driving the increase in wildfire frequency and duration. But modelling wildfires is difficult. Climate models don’t predict wildfires, and they cannot indicate when future extreme events will occur year-on-year. Instead, climate modellers focus on whether they are able to predict the right conditions for events like wildfires, such as high temperatures and strong winds.




Read more:
Siberia heatwave: why the Arctic is warming so much faster than the rest of the world


And these climate model projections show that the kind of extreme summer temperatures we’ve seen in the Arctic in 2020 weren’t likely to occur until the mid-21st century, exceeding predictions by decades.

So even though an increasing trend of high temperatures and conditions suitable for wildfires are predicted in climate models, it’s alarming that these fires are so severe, have occurred in the same region two years in a row, and were caused by conditions which weren’t expected until further in the future.

Fire burns the understory of a boreal woodland.
The Arctic is warming at a faster rate than the global average.
Yelantsevv/Shutterstock

Climate feedback loops

So what is causing this rapid change? Over recent decades, temperatures in the most northerly reaches of Earth have been increasing at a faster rate than the rest of the world, with the polar region heating at more than twice the rate of the global average.

The fires caused by these hot, dry conditions are occurring in remote and sparsely populated forests, tundra and peat bogs, where there is ample fuel.

But these extreme events are also providing worrying evidence of climate “feedback loops”, which were predicted to happen as the climate warms. This is where increasing concentrations of greenhouse gases in the atmosphere contribute to further warming by promoting events – like wildfires – which release even more greenhouse gas, creating a self-perpetuating process that accelerates climate change.




Read more:
Arctic breakdown: what climate change in the far north means for the rest of us


Record CO₂ emissions released from burning Arctic forests during the summer of 2020 will make future conditions even warmer. But ash and other particulates from the wildfires will eventually settle on the ice and snow, making them darker and accelerating their melting by reducing how easily their surface reflects sunlight.

Climate change is not the direct cause of this summer’s fires, but it is helping to create the right conditions for them. The extreme temperatures and wildfires seen throughout the Arctic in 2020 would have been almost impossible without the influence of human-induced climate change – and they are feeding themselves.

Ice surface with black stain from soot.
Soot-stained ice absorbs more of the sun’s heat and melts more quickly.
Trifonov Aleksey/Shutterstock

What about the rest of the world?

When we think of the Arctic, we don’t tend to picture wildfires and heatwaves – we think of snow and ice and long, brutal winters. Yet the region is changing before our eyes. It’s too early to say whether the last two summers represent a permanent step-change, or new “fire regime”, for the Arctic. Only observations over a much longer timescale could confirm this.

But these record-breaking events in the Arctic are being fuelled by human influences that are changing our world’s climate sooner than many expected. With climate models predicting a future where already hot and fire-prone areas are likely to become more so, 2020’s record temperatures paint a worrying trend towards more of the same.

The Arctic is at the frontline of climate change. What we are witnessing here first are some of the most rapid and intense effects of climate change. While the impact is devastating – record CO₂ emissions, damaged forests and soils, melting permafrost – these events may prove to be a portent of things to come for the rest of the world.

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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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