SST sensitivity of a global ocean–atmosphere coupled system to the parameterization of boundary layer clouds

In this note we report on the impact of a more realistic low cloud cover parameterization on the Sea Surface Temperature (SST) predicted by an ocean–atmosphere coupled system. In particular, it is shown that the atmospheric model with more realistic boundary layer clouds leads to a more realistic distribution of the SST in the oceanʹs tropics, subtropics and mid-latitudes. Typical SST biases of up to 5 °C in regions under frequently observed stratus and stratocumulus are substantially reduced to unbiased values at places. This represents a substantial SST forecast improvement in terms of operational coupled systems used in the context of Maritime Rapid Environmental Assessment (MREA).