Meeting radiative forcing targets under delayed participation

In this article we explore several scenarios that aim at meeting radiative forcing targets at 4.5, 3.7, 2.9 and 2.6 W/m 2 by 2100. These scenarios are run under the assumption of participation of all countries by 2012 in climate policy and under the assumption of a significant delay in the participation of Russia and non-Annex I countries (up to 2030 and 2050). The study finds the lowest radiative forcing categories to be feasible under full participation, certainly if overshoot of targets is allowed and when bio-energy and carbon-capture-and-storage is added to the mitigation portfolio. In cases with severe delay in participation, the lowest targets become infeasible. For less strict targets (e.g. 3.7 W/m 2), delayed participation leads to considerable costs increases (up to 90% for the stabilisation case). As a next step, scenarios with less delay in participation need to be explored.