Submitted on August 6, 2009
Accepted on October 7, 2009
Indirect Emissions from Biofuels: How Important?
Jerry M. Melillo 1*, John M. Reilly 2, David W. Kicklighter 1, Angelo C. Gurgel 3, Timothy W. Cronin 4, Sergey Paltsev 2, Benjamin S. Felzer 5, Xiaodong Wang 6, Andrei P. Sokolov 2, C. Adam Schlosser 2
1 The Ecosystems Center, Marine Biological Laboratory, 7 MBL St., Woods Hole, MA 02543, USA.
2 Joint Program on the Science and Policy of Global Change, Massachusetts Institute of Technology, 77 Massachusetts Avenue, MIT E19-411, Cambridge, MA 02139–4307, USA.
3 Joint Program on the Science and Policy of Global Change, Massachusetts Institute of Technology, 77 Massachusetts Avenue, MIT E19-411, Cambridge, MA 02139–4307, USA.; Department of Economics, University of São Paulo, Ribeirão Preto, Brazil.
4 The Ecosystems Center, Marine Biological Laboratory, 7 MBL St., Woods Hole, MA 02543, USA.; Joint Program on the Science and Policy of Global Change, Massachusetts Institute of Technology, 77 Massachusetts Avenue, MIT E19-411, Cambridge, MA 02139–4307, USA.
5 The Ecosystems Center, Marine Biological Laboratory, 7 MBL St., Woods Hole, MA 02543, USA.; EES, Lehigh University, 31 Williams Drive, Bethlehem, PA 18015, USA.
6 School of Public Administration, Zhejiang University, Hangzhou 310000, Zhejiang Province, P. R. China.
* To whom correspondence should be addressed.
Jerry M. Melillo , E-mail: jmelillo{at}mbl.edu
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 examine 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.
