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

Pan, Yude
Birdsey, Richard A.
Fang, Jingyun
Houghton, Richard
Kauppi, Pekka E.
Kurz, Werner A.
Phillips, Oliver L.
Shvidenko, Anatoly
Lewis, Simon L.
Canadell, Josep G.
Ciais, Philippe
Jackson, Robert B.
Pacala, Stephen W.
McGuire, David A.
Piao, Shilong
Rautiainen, Aapo
Sitch, Stephen
Hayes, Daniel

¹U.S. Department of Agriculture Forest Service, Newtown Square, PA 19073, USA.
²Key Laboratory for Earth Surface Processes, Ministry of Education, Peking University, Beijing, 100871 China.
³State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093 China.
⁴Woods Hole Research Center, Falmouth, MA 02543, USA.
⁵University of Helsinki, Helsinki, Finland.
⁶Natural Resources Canada, Canadian Forest Service, Victoria, BC, V8Z 1M5, Canada.
⁷School of Geography, University of Leeds, LS2 91T, UK.
⁸International Institute for Applied Systems Analysis, Laxenburg, Austria.
⁹Global Carbon Project, Commonwealth Scientific and Industrial Research Organization Marine and Atmospheric Research, Canberra, Australia.
¹⁰Laboratoire des Sciences du Climat et de l'Environnement CEA-UVSQ-CNRS, Gif sur Yvette, France.
¹¹Duke University, Durham, NC 27708, USA.
¹²Princeton University, Princeton, N] 08544, USA.
¹³U.S. Geological Survey, Alaska Cooperative Fish and Wildlife Research Unit, University of Alaska, Fairbanks, AK 99775, USA.
¹⁴Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.

^*To whom correspondence should be addressed. E-mail: [email protected]

Science 333(6045):p 988-993, August 19, 2011.

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.