The European Commission published a study by Ecofys, IIASA and E4tech that quantifies the land use change impact of biofuels consumed in the EU. Biofuels are promoted as an option to reduce greenhouse gas emissions from the transport sector.

This paper analyses the effect of different emission metrics and metric values on timing and costs of greenhouse gas mitigation in least-cost emission pathways aimed at a forcing level of 3.5 W m−2 in 2100. Such an assessment is currently relevant in view of UNFCCC's decision to replace the values currently used. An emission metric determines the relative weights of non-CO2 greenhouse gases in obtaining CO2-equivalent emissions.