Woodcache PBC

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

Yude Pan, Richard A. Birdsey, Jingyun Fang, Richard Houghton, Pekka E. Kauppi, Werner A. Kurz, Oliver L. Phillips, Anatoly Shvidenko, Simon L. Lewis, Josep G. Canadell, Philippe Ciais, Robert B. Jackson, Stephen W. Pacala, A. David McGuire, Shilong Piao, Aapo Rautiainen, Stephen Sitch, Daniel Hayes
Peer Reviewed: Yes
Year Published: 2011

Key Takeaways:

  • Forests in the western united states have shown considerably increased mortality related to drought stress, insects, and fires.
  • There was a large carbon sink increase in boreal deadwood caused by natural disturbances in Siberia and Canada.
  • Warmer winters in boreal regions reduce the forest sink through suppressed gross primary production, increased fires, and increased insect damage.
A large and persistent carbon sink in the world's forests


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 T 0.4 petagrams of carbon per year (Pg C year–1) globally for 1990 to 2007. We also estimate a source of 1.3 T 0.7 Pg C year–1 from tropical land-use change, consisting of a gross tropical deforestation emission of 2.9 T 0.5 Pg C year–1 partially compensated by a carbon sink in tropical forest regrowth of 1.6 T 0.5 Pg C year–1. Together, the fluxes comprise a net global forest sink of 1.1 T 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.