A Large and Persistent Carbon Sink in the World's Forests

U.S. Department of Agriculture Forest Service, Newtown Square, PA 19073, USA.
Science (Impact Factor: 31.48). 08/2011; 333(6045):988-93. DOI: 10.1126/science.1201609
Source: PubMed

ABSTRACT The terrestrial carbon sink has been large in recent decades, but its size and location remain uncertain. Using forest inventory
data and long-term ecosystem carbon studies, we estimate a total forest sink of 2.4 ± 0.4 petagrams of carbon per year (Pg
C year–1) globally for 1990 to 2007. We also estimate a source of 1.3 ± 0.7 Pg C year–1 from tropical land-use change, consisting of a gross tropical deforestation emission of 2.9 ± 0.5 Pg C year–1 partially compensated by a carbon sink in tropical forest regrowth of 1.6 ± 0.5 Pg C year–1. Together, the fluxes comprise a net global forest sink of 1.1 ± 0.8 Pg C year–1, with tropical estimates having the largest uncertainties. Our total forest sink estimate is equivalent in magnitude to the
terrestrial sink deduced from fossil fuel emissions and land-use change sources minus ocean and atmospheric sinks.

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Available from: Pekka Kauppi, Aug 14, 2015
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    • "Boreal forests store more than 20 % of the global forest carbon (C) stock (Pan et al. 2011) and are believed to be a net sink of atmospheric C, sequestering approximately 0.5±0.1 Pg C per year (Pan et al. 2011). The circumpolar boreal forest region is of particular interest because it is situated at latitudes expected to undergo substantial warming and climatic changes in the coming decade (Nabuurs et al. 2007), possibly altering forest C stocks and C sink strengths (Koven 2013; Kurz et al. 2008; Ågren et al. 2007). "
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    • ") and could cover about 18% of the global CO 2 release due to deforestation and other land use changes (Pan et al., 2011). "
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