The history and future of IPCC special reports: A dual role of politicisation and normalisation

The special reports of the Intergovernmental Panel on Climate Change (IPCC) have a unique character in IPCC scientific assessment. Their main purpose is to address specific timely issues of policy relevance. This article explores the nature and role of IPCC special reports along the lines of three questions: (1) the history (‘where they come from’); (2) the function (‘what they are doing’); and (3) the future (‘where they are going’). In earlier assessment cycles, special reports were characterised mostly as a direct channel for quickly responding to the request from the United Nations Framework Convention on Climate Change (UNFCCC). The conduct of special reports has been gradually institutionalised to embed its planning in the overall scoping of the entire assessment cycle. More recently, they have become a vehicle to consolidate cross-cutting scientific perspectives and serve the diverse needs of the international policy community, not only the UNFCCC. This historical evolution is, in a sense, the result of striving for greater policy relevance. Special reports have a dual political function—namely, turning into the site or object of politicised debates on science (politicisation) and serving as ‘de facto governance’ with the effect of normalising politically contested ideas (normalisation). This dual function is two different faces emerging from the process into which the IPCC is brought to deal with political controversy. The duality of the two functions also manifests inherent tensions that lie behind the IPCC’s ‘policy-relevant but not policy-prescriptive’ principle. For the future of special reports, the IPCC could reconsider the role of special reports in light of the priority over comprehensive assessment reports, the responsiveness to the UNFCCC request and the selection and scope definition of timely topics. However, there will remain a trade-off between provisional science and lasting political impact caused by the future undertaking of IPCC special reports on any topic.