8.3.2.3 Summary of Oceanic Component Simulation

Overall, the improvements in the simulation of the observed time mean ocean state noted in the TAR (McAvaney et al., 2001) have continued in the models evaluated here. It is notable that this improvement has continued in spite of the fact that nearly all models no longer use flux adjustments. This suggests that the improvements in the physical parametrizations, increased resolution (see Section 8.2) and improved surface fluxes are together having a positive impact on model simulations. The temperature and salinity errors in the thermocline, while still large, have been reduced in many models. In the NH, many models still suffer from a cold bias in the upper ocean which is at a maximum near the surface and may distort the ice-albedo feedback in some models (see Section 8.3.3). In the Southern Ocean, the equatorward bias of the westerly wind stress maximum found in most model simulations is a problem that may affect the models’ response to increasing radiative forcing.