Indirect Emissions from Biofuels: How Important?
Jerry M. Melillo,1,*
John M. Reilly,2
David W. Kicklighter,1
Angelo C. Gurgel,2,3
Timothy W. Cronin,1,2
Sergey Paltsev,2
Benjamin S. Felzer,1,4
Xiaodong Wang,2,5
Andrei P. Sokolov,2
C. Adam Schlosser2
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.
2 Joint 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.
3 Department of Economics, University of São Paulo, Ribeirão Preto 4EES, Brazil.
4 Department of Earth and Environmental Sciences, Lehigh University, 31 Williams Drive, Bethlehem, PA 18015, USA.
5 School 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
