Nature review article: Researchers highlight potential carbon emissions from permafrost thaw

-Contributed by Ted Schuur and Christina Schaedel – The Permafrost Carbon Network is a CliC co-sponsored activity

permafrost carbon networkAs the climate continues to warm, researchers are working to understand how human-driven climate change will affect the release of greenhouse gases from arctic permafrost. Additional carbon emissions from remote places like the Arctic could significantly accelerate the pace of climate change.   

An estimated 1330-1580 billion tons of organic carbon are stored in perennially-frozen (permafrost) soils of Arctic and subarctic regions, with the potential for even higher quantities stored deep in the frozen soil in places that have not yet been adequately quantified. The carbon is made up of plant and animal remnants stored in soil for hundreds to thousands of years. Thawing of frozen soil and subsequent decomposition of organic matter by microbes cause the release of carbon dioxide and methane greenhouse gases into the atmosphere.

Researchers from the Permafrost Carbon Network have worked to synthesize studies on this topic and published the results in a Nature review article in April 2015. According to the authors, the big question is how much, how fast and in what form will this carbon come out. These are the key factors that determine how much impact that permafrost carbon will have on future climate. The authors concluded that, across a range of studies, thawing permafrost in the Artic and sub-Arctic regions appears likely produce a gradual and prolonged release of substantial quantities of greenhouse gases spanning decades as opposed to an abrupt pulse release in a decade or less.

Modern climate change is attributed to human activities as a result of fossil fuel burning and deforestation, but natural ecosystems also play a role in the global carbon cycle. Human activities might start something in motion by releasing carbon gases but natural systems, even in remote places like the Arctic, are likely to add to this problem of climate change.

Citation:  E. A. G. Schuur, A. D. McGuire, C. Schädel, G. Grosse, J. W. Harden, D. J. Hayes, G. Hugelius, C. D. Koven, P. Kuhry, D. M. Lawrence, S. M. Natali, D. Olefeldt, V. E. Romanovsky, K. Schaefer, M. R. Turetsky, C. C. Treat  J. E. Vonk. Climate change and the permafrost carbon feedback. Nature 520, 171–179. 2015. doi:10.1038/nature14338