Climate change is necessarily of interest to a much wider community than climate scientists: it is an issue of concern for human society, and a motivation for potential policy action. For sensible policy action, it is important to make clear what is well-known about climate change, what are significant uncertainties, and what are potential but unquantifiable risks. The RDCEP climate statistics project is intended to understand the projections of large-scale numerical simulations of climate and make their information content accessible to the wider community. This talk will present a simple tutorial framework for understanding the “knowns” of climate change, describe RDCEP climate statistics research and findings on the “known unknowns” (and the problem of the “unknown unknowns”), and discuss the construction of “emulations” of large-scale climate models for use in social science research.