Figure 9.10

Figure 9.10. Observed and hindcast decadal mean surface temperature anomalies (°C) expressed, for each decade, relative to the preceding three decades. Observed anomalies are represented by horizontal black lines. Hindcast decadal anomalies and their uncertainties (5 to 95% confidence bounds) are displayed as vertical bars. Hindcasts are based on a Bayesian detection analysis using the estimated response to historical external forcing. Hindcasts made with CGCM2, HadCM2 (see Table 8.1 of the TAR) and HadCM3 (see Table 8.1 , this report) use the estimated response to anthropogenic forcing only (left hand column of legend) while those made with selected MMD 20C3M models used anthropogenic and natural forcings (centre column of legend; see Table 8.1 for model descriptions). Hindcasts made with the ensemble mean of the selected 20C3M models are indicated by the thick green line. A hindcast based on persisting anomalies from the previous decade is also shown. The hindcasts agree well with observations from the 1950s onward. Hindcasts for the decades of the 1930s and 1940s are sensitive to the details of the hindcast procedure. A forecast for the decadal global mean anomaly for the decade 2000 to 2009, relative to the 1970 to 1999 climatology, based on simulations performed with the Canadian Centre for Climate Modelling and Analysis Coupled Global Climate Model (CGCM2) is also displayed. From Lee et al. (2006).