Abstract
In this paper I analyze strategies policy scientists use to bolster their ethos with American policymakers and the public in the International Panel on Climate Change's (IPCC) Working Group I Summary for Policy Makers (SPM), from their Fourth Assessment Report released in 2007. Specifically, I treat the visualizations of computer climate models included in the SPM as technologies that the IPCC authors used to re-integrate their paradoxical ethos: commissioned to give policy guidance on the basis of their scientific reputation, these authors nevertheless field ethical attacks if their guidance runs counter to prevailing political winds. The visualizations perform continuity between the authors' traditional scientific ethos and their policy ethos. They also shift the locus of persuasion in the SPM from ethical questions to appeals to values and logic (e.g. the results of the climate models).