Governing by targets: reductio ad unum and evolution of the two-degree climate target

Targets are widely employed in environmental governance. In this paper, we investigate the construction of the 2 ?C climate target, one of the best known targets in global environmental governance. Our paper examines this target through a historical reconstruction that identifies four different phases: framing, consolidation and diffusion, adoption, and dis- embeddedness. Our analysis shows that, initially, the target was science-driven and predomi- nantlyEU-based; it then becameprogressively accepted at the international level, despite a lack of broader debate among governments on the policy implications and required measures for implementation.Once the2 ?Ctargetwas endorsedat the level of theUnitedNations, thenature of the targetchangedfrombeingpolicy-prescriptive tobeinglargelysymbolic. In thisphase, the target became a disembedded object in global governance not linked to a shared agenda nor to coordinated andmutually binding mitigation efforts. The 2015 Paris Agreement marks the last stage in this development andmay have further solidified the target as a disembedded object. In the final part of the paper, wesuggestways to overcome the current situation and to develop the 2 ?C target into a fully fledged global environmental governance target.