image: Aerial view of polygonal peatland, Taymyr Peninsula, Northern Siberia. view more
Credit: Image credit: Gustaf Hugelius.
A study examines the potential effects of global warming on carbon and nitrogen stocks in northern peatlands. Northern peatlands hold large stocks of carbon and nitrogen and thus play a key role in global climate dynamics. However, the vulnerability of peatlands to climate warming is uncertain, partly because of a lack of spatially explicit, observation-based peatland maps. Gustaf Hugelius and colleagues generated maps of Northern Hemisphere peatland depth and carbon and nitrogen stocks using data compiled from more than 7,000 field observations. Based on the maps, the authors estimated that northern peatlands cover approximately 3.7 million km2 and store approximately 415 Pg of carbon and 10 Pg of nitrogen. A substantial portion of the carbon and nitrogen stocks are found in peatlands affected by permafrost. The authors estimated that, at present, northern peatlands are a net sink of atmospheric carbon. However, under future global warming scenarios, the authors projected losses of half to nearly all of peatland permafrost. This permafrost thaw would convert the peatlands to a net source of atmospheric carbon, primarily owing to increased methane emissions. According to the authors, the results suggest that although northern peatlands are currently a source of global cooling, permafrost thaw attributable to anthropogenic climate warming may convert peatlands into a net source of warming.
Article #19-16387: "Large stocks of peatland carbon and nitrogen are vulnerable to permafrost thaw," by Gustaf Hugelius et al.
MEDIA CONTACT: Gustaf Hugelius, Stockholm University, SWEDEN; tel: +4670-797-29-52; e-mail: gustaf.hugelius@natgeo.su.se
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Journal
Proceedings of the National Academy of Sciences