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This paper presents an assessment of the impact of the ocean circulation on modeled wave fields in the Southern Ocean, where a systematic positive bias of the modeled wave height against altimetry data has been reported. The inclusion of ocean currents in the wave model considerably reduces the positive bias of the simulated wave height for high southern latitudes. The decrease of wave energy in the presence of currents is almost exclusively related to the reduction of the relative wind, caused by an overall co-flowing current field associated with the Antarctic Circumpolar Current. Improvements of the model results are also found for the peak period and the mean period against a long-term moored buoy. At the mooring location, the effect of currents is greater for larger and longer waves, suggesting remotely generated swells are more influenced by the currents than local waves. However, an additional qualitative analysis using high-resolution currents in a finer grid nested to the global coarser grid shows that typical resolution of global hydrodynamic reanalysis is not sufficient to resolve mesoscale eddies, and as a consequence, the simulation of mesoscale wave patterns can be compromised. The results are also discussed in terms of the accuracy of forcing fields. [ABSTRACT FROM AUTHOR]

A new parameterization of mixing processes in the upper ocean is tested in a 1=48 resolution global ocean climate model. The parameterization represents the effect of turbulent mixing by unbroken waves as an additional turbulent shear production term in the k-epsilon mixing scheme. The results show that the inclusion of this parameterization has a noticeable effect on ocean climate, particularly in regions of high wave activity such as the Southern Ocean. Inclusion of this process also leads to some reduction in the biases of the simulated climate, including mixed layer depth, compared with available observations. [ABSTRACT FROM AUTHOR]