Monday, September 07, 2020

'Zombie Fires' fuel sky-high carbon emissions in the Arctic

http://www.digitaljournal.com/tech-and-science/science/zombie-fires-fuel-sky-high-carbon-emissions-in-the-arctic/article/577595

By Karen Graham

Sept. 7, 2020

"Zombie" wildfires that were smoldering beneath the Arctic ice all winter suddenly flared to life this summer when the snow and ice above it melted, new monitoring data reveals, making this summer's wildfires the worst on record.

In early May, just as the spring thaw was beginning in the northern reaches of Siberia, Mark Parrington spotted something strange on images captured by instruments aboard NASA’s Terra satellite.
Lots of red dots stood out, indicating some kind of thermal anomaly on a vast white expanse. Thomas Smith, an assistant professor in environmental geography at the London School of Economics, quickly noticed that the hot spots were located in areas that had burned in last year’s epic Arctic fires.
 

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Fueled by methane and insulated by the snow - they can burn all winter long. As temperatures begin to climb in the spring and the soil dries out, the fires can reignite aboveground.

This has been the worst year on record for Arctic wildfires, dating back to when monitoring began 17 years ago. In the first half of July, as much carbon was released as a nation the size of Cuba or Tunisia releases in a year. The smoke plumes were so large, they covered the equivalent of more than one-third of Canada.


The Copernicus Atmosphere Monitoring Service (CAMS), implemented by the European Centre for Medium-Range Weather Forecasts (ECMWF) on behalf of the European Union, has been tracking the emissions and activity of more than 100 wildfires occurring across the Arctic Circle in the Sakha Republic of Siberia and Alaska for a number of months.


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"The destruction of peat by fire is troubling for so many reasons," Dorothy Peteet, a a senior research scientist at NASA's Goddard Institute for Space Studies in New York, said. "As the fires burn off the top layers of peat, the permafrost depth may deepen, further oxidizing the underlying peat."


Copernicus estimates that between January and August of 2020, the fires released 244 megatonnes of carbon. That is more carbon than was released in Vietnam for the whole year in 2017.

Parrington says, “We know that temperatures in the Arctic have been increasing at a faster rate than the global average, and warmer/drier conditions will provide the right conditions for fires to grow when they have started. Data from our Global Fire Assimilation System shows that typically fires in the Arctic Circle occur in July and August, so it has been unusual to see fires of this scale and duration in June."

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tags: extreme weather, severe weather,


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