The role of data and priors in estimating climate sensitivity

Abstract In Bayesian theory, the data together with the prior produce a posterior. We show that it is also possible to follow the opposite route, that is, to use data and posterior information (both of which are observable) to reveal the prior (which is not observable). We then apply the theory to equilibrium climate sensitivity as reported by the Intergovernmental Panel on Climate Change (IPCC) in an attempt to get some insights into the prior beliefs of the IPCC scientists.