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A large and persistent carbon sink in the world's forests
Yude Pan1, Richard A Birdsey, Jingyun Fang
1U.S. Department of Agriculture Forest Service, Newtown Square, PA 19073, USA. ypan@fs.fed.us
Science (New York, N.Y.)
|July 19, 2011
Summary
Global forests act as a significant carbon sink, absorbing 2.4 petagrams of carbon annually. Despite uncertainties, this forest carbon sink plays a crucial role in mitigating atmospheric carbon dioxide levels.
Area of Science:
- * Earth System Science
- * Forest Ecology
- * Biogeochemical Cycles
Background:
- * The terrestrial carbon sink's magnitude and geographical distribution are uncertain.
- * Forests are critical components of the global carbon cycle.
- * Recent decades have seen substantial carbon sequestration by land ecosystems.
Purpose of the Study:
- * To quantify the global forest carbon sink from 1990 to 2007.
- * To assess the impact of tropical land-use change on carbon fluxes.
- * To determine the net global forest carbon sink, considering emissions and sequestration.
Main Methods:
- * Utilized forest inventory data for global sink estimation.
- * Incorporated long-term ecosystem carbon studies.
- * Quantified tropical deforestation emissions and forest regrowth sinks.
Main Results:
- * Estimated a total global forest sink of 2.4 ± 0.4 petagrams of carbon per year (Pg C year(-1)).
- * Identified a tropical land-use change source of 1.3 ± 0.7 Pg C year(-1).
- * Calculated a net global forest sink of 1.1 ± 0.8 Pg C year(-1), with high uncertainty in tropical regions.
Conclusions:
- * The global forest carbon sink is substantial, comparable to other major carbon cycle components.
- * Tropical deforestation represents a significant carbon source, partially offset by forest regrowth.
- * Uncertainties in tropical carbon fluxes highlight the need for improved monitoring and research.
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