Abstract

In recent decades, a complex regime of national, regional, and global climate assessments has emerged to apprehend the vast body of evidence on climate change and deliver authoritative reports to policymakers. Focusing on the assessments of the Intergovernmental Panel on Climate Change, this chapter synthesises insights across recent philosophy of science, together with the broader findings of “assessment studies”, to outline the many ways in which social, ethical, and political values impinge on climate assessment reports. Notably, the chapter demonstrates how entrenched social-epistemic features of assessment – features that remain stable despite changes in authorship – constrain the agency of authors and the decisions that can be entertained in assessment. These features include the institutionalisation, political constitution, synthesis-orientation, curatorial nature, and agenda-setting power of assessments. Thus, the chapter provides an institutional analysis of values in climate assessment reports that does not reduce to tracking the psychological states or moral compasses of authoring scientists.