Effects of strongly eddying oceans on multidecadal climate variability in the Community Earth System Model

Abstract. Climate variability on multidecadal timescales appears to be organized in pronounced patterns with clear expressions sea surface temperature, such as the Atlantic Multidecadal Variability and Pacific Decadal Oscillation. These are now well studied both observations global climate models important attribution of change. Results from CMIP5 have indicated large biases these consequences for ocean heat storage mean temperature. In this paper, we use two multi-century Community Earth System Model simulations at coarse (1?) fine (0.1?) model horizontal grid spacing study effects representation mesoscale flows major variability. We find that resolving improves characteristics modes respect increases amplitude content individual basins. strongly eddying model, compared sub-decadal This shift spectral power is seen temperature indices, basin-scale fluxes, implies current CMIP6 generation, which predominantly does not resolve mesoscale, may systematically underestimate