Indirect Emissions from Biofuels: How Important?
- Jerry M. Melillo1,*,
- John M. Reilly2,
- David W. Kicklighter1,
- Angelo C. Gurgel2,3,
- Timothy W. Cronin1,2,
- Sergey Paltsev2,
- Benjamin S. Felzer1,4,
- Xiaodong Wang2,5,
- Andrei P. Sokolov2,
- C. Adam Schlosser2
- 1The Ecosystems Center, Marine Biological Laboratory (MBL), 7 MBL Street, Woods Hole, MA 02543, USA.
- 2Joint Program on the Science and Policy of Global Change, Massachusetts Institute of Technology (MIT), 77 Massachusetts Avenue, MIT E19-411, Cambridge, MA 02139-4307, USA.
- 3Department of Economics, University of São Paulo, Ribeirão Preto 4EES, Brazil.
- 4Department of Earth and Environmental Sciences, Lehigh University, 31 Williams Drive, Bethlehem, PA 18015, USA.
- 5School of Public Administration, Zhejiang University, Hangzhou 310000, Zhejiang Province, People’s Republic of China (PRC).
- ↵*To whom correspondence should be addressed. E-mail: jmelillo{at}mbl.edu
Abstract
A global biofuels program will lead to intense pressures on land supply and can increase greenhouse gas emissions from land-use changes. Using linked economic and terrestrial biogeochemistry models, we examined direct and indirect effects of possible land-use changes from an expanded global cellulosic bioenergy program on greenhouse gas emissions over the 21st century. Our model predicts that indirect land use will be responsible for substantially more carbon loss (up to twice as much) than direct land use; however, because of predicted increases in fertilizer use, nitrous oxide emissions will be more important than carbon losses themselves in terms of warming potential. A global greenhouse gas emissions policy that protects forests and encourages best practices for nitrogen fertilizer use can dramatically reduce emissions associated with biofuels production.
- Received for publication 6 August 2009.
- Accepted for publication 7 October 2009.
