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Wednesday, 24 June 2020

The Arctic is on fire: Siberian heat wave alarms scientists


The Arctic is feverish and on fire—at least parts of it are. And that's got scientists worried about what it means for the rest of the world.



The thermometer hit a likely record of 38 degrees Celsius (100.4 degrees Fahrenheit) in the Russian Arctic town of Verkhoyansk on Saturday, a temperature that would be a fever for a person—but this is Siberia, known for being frozen. The catastrophic oil spill from a collapsed storage tank last month near the Arctic city of Norilsk was partly blamed on melting permafrost. In 2011, part of a residential building in Yakutsk, the biggest city in the Sakha Republic, collapsed due to thawing and subsidence of the ground.

Last August, more than 4 million hectares of forests in Siberia were on fire, according to Greenpeace. This year the fires have already started raging much earlier than the usual start in July, said Vladimir Chuprov, director of the project department at Greenpeace Russia.

Persistently warm weather, especially if coupled with wildfires, causes permafrost to thaw faster, which in turn exacerbates global warming by releasing large amounts of methane, a potent greenhouse gas that's 28 times stronger than carbon dioxide, said Katey Walter Anthony, a University of Alaska Fairbanks expert on methane release from frozen Arctic soil.

"Methane escaping from permafrost thaw sites enters the atmosphere and circulates around the globe," she said. "Methane that originates in the Arctic does not stay in the Arctic. It has global ramifications."

And what happens in the Arctic can even warp the weather in the United States and Europe.



In the summer, the unusual warming lessens the temperature and pressure difference between the Arctic and lower latitudes where more people live, said Judah Cohen, a winter weather expert at Atmospheric Environmental Research, a commercial firm outside Boston.

That seems to weaken and sometimes even stall the jet stream, meaning weather systems such as those bringing extreme heat or rain can stay parked over places for days on end, Cohen said.

According to meteorologists at the Russian weather agency Rosgidrome t, a combination of factors—such as a high pressure system with a clear sky and the sun being very high, extremely long daylight hours and short warm nights—have contributed to the Siberian temperature spike.


"The ground surface heats up intensively. .… The nights are very warm, the air doesn't have time to cool and continues to heat up for several days," said Marina Makarova, chief meteorologist at Rosgidromet.

Makarova added that the temperature in Verkhoyansk remained unusually high from Friday through Monday.

Scientists agree that the spike is indicative of a much bigger global warming trend.

"The key point is that the climate is changing and global temperatures are warming," said Freja Vamborg, senior scientist at the Copernicus Climate Change Service in the U.K. "We will be breaking more and more records as we go."

"What is clear is that the warming Arctic adds fuel to the warming of the whole planet," said Waleed Abdalati, a former NASA chief scientist who is now at the University of Colorado.



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