Climatic teleconnections between the tropical and polar North Atlantic during the last interglacial period

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The proposed study aims at reconstructing the development of the meridional surface ocean temperature gradients between the low and high latitude North Atlantic across the entire last interglacial cycle (MIS5e/Eemian), i.e., from its onset during deglaciation (Termination 2) to its end during glacial inception (MIS5d). Marine sediment cores from key locations in the North Atlantic will be employed. These sites control the western tropical/subtropical gyre and northward water flow from the Southern Ocean; the origin of the Gulf Stream; the warm (Atlantic) and cold (polar) water currents of the Nordic Seas. Methods applied will be based on foraminiferal assemblage studies and stable isotopes (O/C), geochemical analyses of biomarker (UK37) and of the elemental composition of the bulk sediment (XRF scanning). The data will not only allow a better assessment of naturally-forced changes in past ocean surface properties (temperature-salinity) during the Eemian, the cross-latitudinal, multi-proxy approach will also provide an improved oceanic data base to better constrain numerical climate models.