Burden sharing of climate change mitigation: global and regional challenges under shared socio-economic pathways

We analyze the burden sharing of climate stabilization under socio-economic scenario uncertainty and for various burden-sharing regimes. For this purpose, we quantify mitigation efforts in terms of emission reductions and mitigation costs for a number of major world regions, considering scenarios with and without climate finance. The influence of socio-economic drivers on the burden sharing is crucial, but it has not yet been studied in the context of the most recent scenario framework-the shared socio-economic pathway scenarios (SSPs). Here, we show that sustainable development as represented by the SSP1 scenario reduces the challenges of burden sharing and makes it easier to achieve equitable climate policies. In contrast, in a scenario with fossil-fueled development (SSP5), the risk of political infeasibility-measured by the variation of mitigation costs across regions and the amount of implied international transfers-increases with most burden-sharing regimes.