The role of the East Greenland Current in the North Atlantic climate variability during the last 200 years

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Variations in polar freshwater export via the East Greenland Current (EGC) can affect thermohaline circulation and the strength of the Subpolar Gyre and, therefore, can modulate the northward heat transport in the North Atlantic Ocean. To assess the role of the EGC in the 20th century warming and its relation to North Atlantic climate variability, its palaeoceanographic history and spatial extent will be studied at three key sites; on the central East Greenland shelf (core of the East Greenland Current, site1), the North Iceland shelf (site 2) and the Denmark Strait on the SE Greenland shelf, in the area of the Polar Front. For the first time, palaeoceanographic data sets, spanning the most recent past and the 20th century, for the EGC core will be produced at a sub-decadal time scale. These detailed studies based on foraminiferal assemblages, supplemented with alkenone analyses at site 2 and 3, will allow to asses if and how modern warming is manifested in drift/sea ice and freshwater flux of the EGC. For this aim, new short sediment cores will be obtained during a cruise of the Norwegian RV G.O. Sars in summer 2015. The proposed reconstructions will be linked to marine and terrestrial high-resolution studies from the North Atlantic Drift, the West Greenland Current, the Fram Strait, the Baltic Sea and continental Europe, in order to investigate the timing (in-phase/out-of-phase) since the Little Ice Age in the different regions. Reconstructing the role of the EGC at high resolution will increase our understanding of trigger mechanisms underlying climate variability in the North Atlantic region during the 20th century.