More wildfires = more warming = more wildfires

[xchrom]

http://grist.org/climate-energy/more-wildfires-more-warming-more-wildfires/

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U.S. Army Corps of Engineers
A view inside Alaska’s unique permafrost research tunnel

To step into the U.S. Army Corp of Engineers’ Permafrost Tunnel Research Facility in Fox, Alaska — just north of Fairbanks — is to step back in time. Burrowed into the silt layers of an unassuming hillside, the tunnel is like a scene out of a subarctic Indiana Jones adventure. Shivering, you walk the length of an underground football field, past protruding bones of Ice Age animals (including mammoths) and huge ice wedges, which were frozen in place long before Hebrew scribes compiled the Old Testament. The smell is overpowering: Dead plants and other organic materials are suspended in the frozen soil walls, decomposing and reverting back into the carbon dioxide and water from which they were originally formed. But because of the cold, that process is extremely slow: Deep in the cave, a 32,000-year-old frozen plant sticks out of a wall. It’s still green. The leaves still contain chlorophyll.

That plant, like the permafrost cave as a whole, is in a state of frozen suspension. But walking through the tunnel, you’re acutely aware of how quickly that suspension might end. The facility is maintained through a cooling system at 25 degrees F, without which the cave would collapse, and the ancient geological history lesson would be abruptly over. And the carbon that had slowly accumulated in the soils of the cave over tens of thousands of years? Much of it would be released into the air.

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National Park Service
A fire burns alongside a still frozen river in the Alaska wilderness.

Throughout Alaska and similar northern or “boreal” environments across the world (from Canada to Russia), huge volumes of permafrost hang in a similar balance. In much of this region, ground temperatures are just below freezing, leaving their frozen soils right on the cusp of thawing. “It’s kind of at the thermal tipping point” for permafrost, explains Rich Boone, an ecologist at the University of Alaska-Fairbanks. What might tip it over? Climate change, which is currently proceeding twice as fast in Alaska and the Arctic as it is in the mid-latitudes. And the warming releases a pulse of carbon from these frozen soils, as microorganisms break down the organic matter they contain and give off carbon dioxide (and, sometimes, methane). How much? Well, it is estimated that global permafrost contains twice as much total carbon as the planet’s atmosphere currently does. In other words, a lot.

[pscot]

1. A most excellent OP