A Bayesian ANOVA scheme for calculating climate anomalies, with applications to the instrumental temperature record

This Bayesian scheme is used to re-express the CRU data set as anomalies with respect to means calculated over the entire 1850-2009 interval spanned by the data set. The mean standard deviation is increased to 0.69 C within the original 1961-1990 reference interval, and reduced to 0.76 C elsewhere. The choice of reference interval thus has a predictable and demonstrable effect on the second spatial moment time series of the CRU data set.

The spatial mean time series is in this case largely unaffected: the amplitude of spatial mean temperature change is reduced by 0.1 C when using the 1850-2009 reference interval, while the 90% uncertainty interval of (-0.03, 0.23) indicates that the reduction is not statistically significant.