The influence of Arctic freshwater export on the North Atlantic circulation
Arctic freshwater has the potential to influence the North Atlantic circulation through its impact on stratification and hence deep covection. Freshwater export is accomplished through two major gateways, the Canadian Arctic Archipelago (CAA) and Fram Strait. In this modelling study we show that the realism of the representation of the CAA in sea ice-ocean models does have a substantial influence on the North Atlantic circulation. More specifically, we use the Finite Element Sea Ice-Ocean Model (FESOM) with (5km) and without (25km) regional refinement in the CAA. It turns out that increasing resolution in the CAA to 5km increases the freswater export through the CAA leading to enhanced Labrador Sea convection and an associated strengthening of the MOC by about 10%. The physical mechanisms behind this sensitivity will be described in detail.