Article

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: 33.61). 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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    • "e l s e v i e r . c o m / l o c a t e / f o r e c o stock (Pan et al., 2011). In the southern boreal forest, mean annual temperatures have risen %1.5 °C since 1940 (Bale et al., 2002; Battisti et al., 2005; Netherer and Schopf, 2010) and are expected to increase an additional 3–7 °C in winter and 3–11 °C in summer by 2100 (Kling et al., 2003). "
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