The Southern Ocean in climate models
This presentation summarizes two recent modelling studies which were based on CMIP5 model data in the Southern Ocean. The first part focuses on open ocean convection events in the Southern Ocean, a spurious process, and the variability which is associated with it in coupled climate models. We find that models which open ocean convection show distinct larger variability in the Ross, Weddell Gyre and Drake transport than non-convective models. This additional variability challenges the use of those models to invested climate change related signals. The second part of the presentation focuses on the biogeochemical representation in the Ross Sea and how CMIP5 models perform in this region. A detailed model evaluation is presented. Clear outliers have been identified, and providing increased confidence about the future model projections of the remaining ensemble. An outlook about ongoing work in New Zealand within the Deep South project will be given.