A large and persistent carbon sink in the world's forests

Y. Pan; R.A. Birdsey; J. Fang; R. Houghton; P.E. Kauppi; W.A. Kurz; O.L. Phillips; A. Shvidenko; S.L. Lewis; J.G. Canadell; P. Ciais; R.B. Jackson; S.W. Pacala; A. David McGuire; S. Piao; A. Rautiainen; S. Sitch; D. Hayes

doi:10.1126/science.1201609

USGS · 70034599

A large and persistent carbon sink in the world's forests

Y. Pan·R.A. Birdsey·J. Fang·R. Houghton·P.E. Kauppi·W.A. Kurz·O.L. Phillips·A. Shvidenko·S.L. Lewis·J.G. Canadell·P. Ciais·R.B. Jackson·S.W. Pacala·A. David McGuire·S. Piao·A. Rautiainen·S. Sitch·D. Hayes

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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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Y. Pan, R.A. Birdsey, J. Fang, R. Houghton, P.E. Kauppi, W.A. Kurz, O.L. Phillips, A. Shvidenko, S.L. Lewis, J.G. Canadell, P. Ciais, R.B. Jackson, S.W. Pacala, A. David McGuire, S. Piao, A. Rautiainen, S. Sitch, D. Hayes. 2011. A large and persistent carbon sink in the world's forests. https://doi.org/10.1126/science.1201609

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