This paper uses a vote-counting procedure to estimate the probability density function of the total economic impact as a parabolic function of global warming. There is a wide range of uncertainty about the impact of climate change up to 3°C, and the information becomes progressively more diffuse beyond that. Warming greater than 3°C most likely has net negative impacts, and warming greater than 7°C may lead to a total welfare loss. The expected value of the social cost of carbon is about $29/tC in 2015 and rises at roughly 2% per year. © 2012 The Author(s).