Indirect Land Use Impacts of United States Biofuel Policies: The Importance of Acreage, Yield, and Bilateral Trade Responses

Recent analysis has highlighted agricultural land conversion as a significant debit in the greenhouse gas accounting of ethanol as an alternative fuel. A controversial element of this debate is the role of crop yield growth as a means of avoiding cropland conversion in the face of biofuels growth. We find that standard assumptions of yield response are unduly restrictive. Furthermore, we identify both the acreage response and bilateral trade specifications as critical considerations for predicting global land use change. Sensitivity analysis reveals that each of these contributes importantly to parametric uncertainty.