Anything by Demetris Koutsoyiannis is always worth spending time on. Spence_UK draws our attention to this recent presentation at AGU asking:
How well do the models capture the scaling behaviour of the real climate, by assessing standard deviation at different scales. (Albeit at a regional, rather than global level).
Assessment of the reliability of climate predictions based on comparisons with historical time series (Click on “Presentation” to get through abstract page)