Modular Extrapolation Approach for Crop LCA MEXALCA: Global Warming Potential of

MEXALCA (Modular EXtrapolation of Agricultural LCA) extrapolates crop inventory data and impacts from an original country inventory to all producing countries worldwide. This allows estimates of worldwide means weighted by production volumes and of the environmental impact distribution. In this paper, the relationship between the yield and the environmental impacts is analysed in order to test whether the yield alone can be used as an extrapolation criterion. The results show that the global warming potential (GWP) per kg decreases with increasing yields for the means of the 27 studied crops. When comparing the production of a crop in different countries, the relationship between GWP per kg and yield exists only for those crops where the contribution from basic cropping operations and tillage to the GWP is significant. Considering the yield alone therefore generally allows only a poor approximation of the GWP.