Abstract

Northern peatlands contain a large terrestrial carbon pool that plays an important role in the Earth’s carbon cycle. A considerable fraction of this carbon pool is currently in permafrost and is biogeochemically relatively inert; this will change with increasing soil temperatures as a result of climate warming in the 21st century. We use a geospatially explicit representation of peat areas and peat depth from a recently-compiled database and a geothermal model to estimate northern North America soil temperature responses to predicted changes in air temperature. We find that, despite a widespread decline in the areas classified as permafrost, soil temperatures in peatlands respond more slowly to increases in air temperature owing to the insulating properties of peat. We estimate that an additional 670 km3 of peat soils in North America, containing ∼33 Pg C, could be seasonally thawed by the end of the century, representing ∼20 % of the total peat volume in Alaska and Canada. Warming conditions result in a lengthening of the soil thaw period by ∼40 days, averaged over the model domain. These changes have potentially important implications for the carbon balance of peat soils.

Publication Date

6-24-2011

Journal Title

Earth System Dynamics

Publisher

Copernicus Publications

Digital Object Identifier (DOI)

10.5194/esd-2-121-2011

Document Type

Article

Rights

© Author(s) 2011. This work is distributed under the Creative Commons Attribution 3.0 License.

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