Combined Climate and Carbon-Cycle Effects of Large-Scale Deforestation

Journal Article · Tue Oct 17 04:00:00 EDT 2006 · Proceedings of the National Academy of Sciences, N/A, no. 16, April 17, 2007, pp. 6550-6555

OSTI ID:907848

Bala, G; Caldeira, K; Wickett, M; Phillips, T J; Lobell, D B; Delire, C; Mirin, A

The prevention of deforestation and promotion of afforestation have often been cited as strategies to slow global warming. Deforestation releases CO{sub 2} to the atmosphere, which exerts a warming influence on Earth's climate. However, biophysical effects of deforestation, which include changes in land surface albedo, evapotranspiration, and cloud cover also affect climate. Here we present results from several large-scale deforestation experiments performed with a three-dimensional coupled global carbon-cycle and climate model. These are the first such simulations performed using a fully three-dimensional model representing physical and biogeochemical interactions among land, atmosphere, and ocean. We find that global-scale deforestation has a net cooling influence on Earth's climate, since the warming carbon-cycle effects of deforestation are overwhelmed by the net cooling associated with changes in albedo and evapotranspiration. Latitude-specific deforestation experiments indicate that afforestation projects in the tropics would be clearly beneficial in mitigating global-scale warming, but would be counterproductive if implemented at high latitudes and would offer only marginal benefits in temperate regions. While these results question the efficacy of mid- and high-latitude afforestation projects for climate mitigation, forests remain environmentally valuable resources for many reasons unrelated to climate.

• Research Organization: Lawrence Livermore National Laboratory (LLNL), Livermore, CA
• Sponsoring Organization: USDOE
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 907848
• Report Number(s): UCRL-JRNL-225431
• Journal Information: Proceedings of the National Academy of Sciences, N/A, no. 16, April 17, 2007, pp. 6550-6555, Journal Name: Proceedings of the National Academy of Sciences, N/A, no. 16, April 17, 2007, pp. 6550-6555 Vol. 16
• Country of Publication: United States
• Language: English

Related Subjects

09 BIOMASS FUELS
54 ENVIRONMENTAL SCIENCES
ALBEDO
CARBON CYCLE
CLIMATE MODELS
CLIMATES
CLOUD COVER
DEFORESTATION
FORESTS
GREENHOUSE EFFECT
MITIGATION