A dynamical link between the Arctic and the global climate system

By means of simulations with a global coupled AOGCM it is shown that changes in the polar energy sink region can exert a strong influence on the mid‐ and high‐latitude climate by modulating the strength of the mid‐latitude westerlies and storm tracks. It is found, that a more realistic sea‐ice and snow albedo treatment changes the ice‐albedo feedback and the radiative exchange between the atmosphere and the ocean‐sea‐ice system. The planetary wave energy fluxes in the middle troposphere of mid‐latitudes between 30 and 50°N are redistributed, which induces perturbations in the zonal and meridional planetary wave trains from the tropics over the mid‐latitudes into the Arctic. It is shown, that the improved parameterization of Arctic sea‐ice and snow albedo can trigger changes in the Arctic and North Atlantic Oscillation pattern with strong implications for the European climate.