Thursday, August 23, 2018

Arctic Climate Feedback Loops: Heat, Melting Ice and Fires

The Arctic is being ravaged by a trifecta of three interrelated phenomenon that are all connected by climate change. Global warming is contributing to more heat waves. Hotter average temperatures in the Arctic are also melting the ice and causing wildfires.

These three phenomenon are interacting synergistically to amplify climate changes. These interrelationships can also be described as climate feedback loops, meaning they are vicious cycles that accelerate warming. Various permutations of feedback loops can be found between these three phenomenon.


Heat Waves

This year's hot summer is but the latest example of decades of hot data. Weather in the Arctic is completely out of whack and this should concern us all. The world is warming because of climate change but in the Arctic that warming is taking place twice as fast.  The Arctic acts a a global climate regulator, so what we see happening there has implications for us all.

Climate change is causing the Arctic spring to start 16 days early than it did a decade ago, it is also causing algae blooms. This is the finding of a study by researchers from the University of California, Davis that was published last March in the journal Scientific Reports. Last winter the temperature in the Arctic was 3°C warmer than average and in the month of February it was 10°C warmer in some places.

These Arctic heatwaves are unprecedented and they have stunned scientists. "The extended warmth really has staggered all of us," said Ruth Mottram, a climate scientist at the Danish Meteorological Institute. Calling these heatwaves statistical anomalies belittles the reality. "It’s just crazy, crazy stuff," said Mark Serreze, director of the National Snow and Ice Data Center in Boulder Colorado.

In Northern Siberia, along the coast of the Arctic Ocean temperatures were 90°F on July fifth that is 40°F above normal. "It is absolutely incredible and really one of the most intense heat events I’ve ever seen for so far north," meteorologist Nick Humphrey was quoted as saying in the Washington Post.

Melting Ice

This record breaking warmth is occurring against the backdrop of melting ice. We are seeing diminishing sea ice, declining glaciers and thawing permafrost both on land and on the ocean floor.

Last February, Arctic sea ice had shrunk 62,000 square miles below last year's record low. This is more than a half a million square miles below the 30 year normal.  Recently a massive section of ice disappeared in Greenland. Ice is disappearing in the Arctic and there is not much doubt about why. "Climate change is the overriding thing," data center senior scientist Walt Meier said.

Melting ice also increases temperatures through a phenonomenon known as the albeido effect.  Ice reflects light back into space, when there is less ice, less light is reflected back into space and this drives surface temperatures even higher.

Climate change has shrunk the glacier on Sweden's highest peak. A Stockholm University geography professor claims that during July the summit of Kebnekaise mountain fell by four metres and is no long Sweden's highest peak. Glaciers in Canada's high Arctic are also disappearing according to satellite imagery. The 200 meter thick ice shelves are collapsing at an increasing rate and risk disappearing altogether. This is the conclusion of researchers from the University of Ottawa who published a study in June in the Journal of Glaciology. European and Canadian glaciers are not the only Arctic glaciers that are melting, so are those in Alaska.

The most obvious consequence of melting Arctic ice is sea level rise, however there are other even more apocalyptic implications. The permafrost on the ground and on the ocean floor is also melting and this is unleashing vast quantities of methane a potent greenhouse gas.

The permafrost is also releasing CO2 the primary GHG. It only covers around 8 percent of the Arctic land surface but there is 1,500 billion tons of carbon locked in the permafrost. This is half the global total in amount of carbon the ground and twice the amount of CO2 currently in the atmosphere. According to a NASA study published last month the rate at which carbon is released from the permafrost into the atmosphere is accelerating.  The study concluded that Arctic carbon spends 13 percent less time locked in frozen soil that it did four decades ago. 

Approximately 1.9 million square kilometres of the Arctic is composed of either forested and non-forested peatland. When Arctic peatlands thaw they are also prone to greenhouse gas intensive wildfires.

Wildfires

The link between climate change heat and wildfires is increasingly well documented. Extreme heat in the Arctic is causing unprecedented wildfires that have serious global implications.  Severe drought and heat in northern Sweden ignited more than 80 wildfires this summer that burned more than 30,000 hectares across the country.

A total of at least 11 large fires burned in Sweden's Arctic. The main culprit appears to be the hot dry conditions which have made vegetation highly combustible. Four northern Swedish communities were evacuated and tens of thousands have been cautioned to remain indoors to reduce smoke inhalation.

Sweden is not the only Arctic nation that has been plagued with wildfires. A bit more than one year ago Greenland's thawed peatland was ablaze, in 2014 fires ravaged parts of Canada's Boreal forest. Russia has also seen an increase in fires in the far north as has Norway, Finland, and the United States.

The Guardian quotes climate scientist Vincent Gauci as saying that heat as the catalyst that make these fires possible. The threat can be expected to increase as the planet continues to warm.

Wildfires are not only caused by climate change, they also add to it. Wildfires spew vast amounts of carbon into the atmosphere and this causes planetary warming that is exacerbated by increasing Arctic wildfires. To add insult to injury, wildfires in the Arctic can dramatically darken sea ice reducing the albeido effect and further accelerate warming.

Feedback loops

The Arctic is especially prone to negative climate feedback loops. Climate change induced warming causes wildfires that emit carbon and increase global warming. Heat also causes the thawing and drying of Arctic peatlands and when they burn they release significantly more carbon than wildfires elsewhere. This accelerates global warming and sets the stage for more fires.

The feedback loops between heat, ice and fire may even augur tipping points from which we have no hope of recovering.

Related
Heat Connects Wildfires to Climate Change
Why the Fate of the Arctic Should be of Concern to Us All
The Dangerous Feedback Loop Between Wildfires and Climate Change
Feedback Loops Between Wildfires Peat and Carbon
Arctic Warming Feedback Loops: Algae Blooms and Thawing Permafrost
Extreme Weather and Fossil Fuels Feedback Loop Makes the Case for Clean Energy
The State of Arctic Warming and Melting Ice
Rising CO2 Emissions and Ongoing Heat Records Especially in the Arctic
More Evidence of Historic Arctic Warming: Lake Sediment and Ice Cores
Arctic Sea Ice is Disappearing

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