The emissions gap report 2013: a UNEP synthesis report

This report confirms and strengthens the conclusions of previous analyses that current pledges and commitments fall short of set goals. It further says that, as emissions of greenhouse gases continue to rise rather than decline, it becomes less likely that emissions will be low enough by 2020 to be on a least-cost pathway towards meeting the 2e C target. As a result, after 2020, the world will have to rely on more difficult, costlier and riskier means of meeting the target. The further from the least-cost level in 2020, the higher these costs and the greater the risks will be. If the gap is not closed or significantly narrowed by 2020, the door to many options to limit temperature increase to 1.5e C at the end of this century will be closed, further increasing the need to rely on accelerated energy-efficiency increases and biomass with carbon capture and storage for reaching the target.