Paleoceanological Conditions on the Northern Segment of the Mohns Ridge (Norwegian Sea) at the End of the Middle Pleistocene Based on the Dinocyst Analysis

New paleoceanological data for the northern part of the Norwegian Sea were obtained for the marine oxygen isotope stages (MIS) 8–6. Dinocyst analysis, performed on the sediment core AMK-5536, showed that during cold MIS 6 and MIS 8, the local environments were formed in close proximity to the Arctic Front with probable presence of sea ice. In the warm MIS 7, the dramatic increase in dinocyst concentrations with high species diversity, and the appearance of warm-water taxa with typical species Spiniferites septentrionalis were noted. The MIS 7 optimum corresponds to the time of ~240–236 ka. The warming was short-lived and strongly pronounced. The influence of the North Atlantic warm and saline sea-surface waters was greater than at present; the Arctic Front shifted northward. The reconstructed sea-surface temperature was approximately 2.9–3.6°C higher than the modern one.