Millennial-scale palaeoceanographic variability of the North Atlantic through Marine Isotope Stage M2 in the warm mid-Pliocene

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The proposed project will apply palynology and geochemical data from foraminifers to investigate the North Atlantic palaeoceanographic variability around Marine Isotope Stage M2 (mid-Pliocene, ca. 3.3 Ma). Marine Isotope Stage (MIS) M2 is a mid-Pliocene global cooling event that can be seen as a first attempt of the climate system to switch into a ‘Quaternary mode’. Preliminary studies have hinted that oceanographic changes in the Pliocene North Atlantic can occur on timescales of less than ten thousand years. Firstly, this project will establish a millennial scale record across MIS M2 from four sites along a north-south transect in the North Atlantic. This will test the hypothesis that the North Atlantic Current can suddenly weaken even during warmer climate conditions of the Pliocene. Furthermore, the transect will allow assessing how mid-Pliocene ocean circulation compares with the Quaternary and present-day circulation. Understanding the mechanisms of ocean circulation during a globally warmer climate is highly relevant for understanding possible future conditions of planet Earth. Secondly, the geochemical and palynological dataset along the north-south transect will reflect a gradient of different climatic conditions and palaeoenvironmental settings around MIS M2. This is essential to identify the environmental preferences of extinct dinoflagellate species – a major challenge in palaeoecological studies.