Figure 8.4. Root-mean-square (RMS) model error, as a function of latitude, in simulation of (a) outgoing SW radiation reflected to space and (b) outgoing LW radiation. The RMS error is calculated over all longitudes and over all 12 months of a climatology formed from several years of data. The RMS statistic labelled ‘Mean Model’ is computed by first calculating the multi-model monthly mean fields, and then calculating the RMS error (i.e., it is not the mean of the individual model RMS errors). The Earth Radiation Budget Experiment (ERBE; Barkstrom et al., 1989) observational estimates used here are for the period 1985 to 1989 from satellite-based radiometers, and the model results are for the same period in the 20th-century simulations in the MMD at PCMDI. See Table 8.1 for model descriptions. Results for individual models can be seen in the Supplementary Material, Figures S8.5 to S8.8.