The Institutional Design of Scientific Advisory Boards on Climate Change: A Comparison at the Intergovernmental, Supranational, and National Level.

This article investigates the institutional design of scientific advisory bodies (SABs) on climate change across three levels of governance: intergovernmental Intergovernmental Panel on Climate Change (IPCC), national (UK's Climate Change Committee (CCC)), and supranational (European Scientific Advisory Board on Climate Change - ESABCC). Drawing on original empirical data and comparative analysis, the paper examines how institutional features (mandate, composition, autonomy, capacity, and knowledge provision) shape the potential roles and influence of these bodies in climate governance. The ESABCC, established in 2021, represents a novel institutional innovation within the EU's climate policy architecture. As the first supranational advisory body of its kind, it navigates a complex political space, balancing scientific independence with embeddedness in European Union's (EU) policymaking structures. Through a comparative lens, the analysis shows that while all three bodies aim to provide credible scientific input, their design reflects different governance logics and degrees of proximity to policy. The paper argues that institutional design is a critical determinant of how effectively SABs contribute to legitimate, evidence-informed climate policy. By mapping the ESABCC's position within the EU's multi-level governance framework, the study highlights its evolving role and outlines the implications for the broader use of expert knowledge in turbulent policy environments.