Projected changes in the ocean mixed layer depth over the North Pacific from IPCC AR4 models

Abstract

We estimate changes in the mixed layer depth (MLD)over the North Pacific under global warming using global climate model projections from the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC AR4) . The mixed layer depths are generally found to be shallowing up to 50 % in most of the North Pacific, supporting the idea that strengthened stratification would reduce MLD under global warming. MLD deepening is observed in the Kuroshio extention region and parts of the Bering Sea and Sea of Okhotsk, which is shown to be related with changes in the surface wind stress or sea ice, indicating that local processes also contribute to the MLD changes.