Add to ORKGClimate change has become increasingly important in both the media and politics over the past decades. Considered as radically global, because greenhouse gas emissions in one part of the world have an impact on the whole planet, the climate risk is impossible to detect or to combat without the help of the natural, economic and social sciences. Climate change thus poses fundamental questions concerning the relationship between different scales of human action, and the organization of scientific expertise in the governance of environmental problems. In this thesis, we ask how climate change has emerged as a public problem, and how specific interpretations of the problem have become dominant in four different contexts: in the global arena of U...