How Green Is Sugarcane Ethanol?
利用巴西甘蔗活动的遥感数据，通过动态土地利用模型估算甘蔗乙醇供给中面积扩张与产量提升的贡献，发现边际上92%的新乙醇来自面积增加，长期直接森林砍伐占面积扩张的19%，并评估乙醇政策对碳排放和森林砍伐的影响。
Abstract Biofuels offer one approach for reducing carbon emissions. However, the necessary agricultural expansion may endanger tropical forests. I use a dynamic model of land use to disentangle the roles of acreage and yields in the supply of sugarcane ethanol in Brazil. The model is estimated using remote sensing (satellite) information of sugarcane activities. Estimates imply that, at the margin, 92% of new ethanol comes from increases in area and only 8% from increases in yield. Direct deforestation accounts for 19% of area expansion at the margin in the long run. I further assess carbon emissions and deforestation implications from ethanol policies.