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Title: Arctic wildfires at a warming threshold
Vast amounts of organic carbon are stored in Arctic soils. Much of this is in the form of peat, a layer of decomposing plant matter. Arctic wildfires release this carbon to the atmosphere as carbon dioxide (CO 2 ) ( 1 ) and contribute to global warming. This creates a feedback loop in which accelerated Arctic warming ( 2 ) dries peatland soils, which increases the likelihood of bigger, more frequent wildfires in the Arctic and releases more CO 2 , which further contributes to warming. Although this feedback mechanism is qualitatively understood, there remain uncertainties about its details. On page 532 of this issue, Descals et al. ( 3 ) analyze data from the 2019 and 2020 wildfire seasons in the Siberian Arctic and predict the extent of carbon-rich soils likely to burn in the area with future warming. Critically, they suggest that even minor increases in temperature above certain thresholds may promote increasingly larger wildfires.  more » « less
Award ID(s):
1636476 1708344 2224776
PAR ID:
10399389
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Science
Volume:
378
Issue:
6619
ISSN:
0036-8075
Page Range / eLocation ID:
470 to 471
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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