Influence of the Global Thermohaline Circulation on Paleoceanographic Events in the Eurasian Arctic Seas

Abstract

At present, the Eurasian Arctic seas exhibit strong AMOC influence and, in turn, affect the NADW formation due to variability of freshwater outflow to the North Atlantic. The heat and salt exchange between the Atlantic and Arctic varied widely on glacial–interglacial, millennial, and shorter time scales. The postglacial history of the western Eurasian seas comprises three major phases. The proximal glaciomarine sediments (marine diamicton) of the early deglaciation (ca. 19–15 cal. ka BP.) are generally barren. However, recent data allow us to admit relatively persistent, although temporarily variable, Atlantic water penetration into the Arctic seas already since 17–16 cal. ka BP. The distal glaciomarine sediments of the late deglaciation (ca. 15–11.4 cal. ka BP.) contain diverse and abundant benthic microfossils only below the main Atlantic water pathways, in the southwestern Barents Sea, on the Svalbard shelf, and on the Laptev Sea slope. In the Barents Sea, paleoenvironments changed dramatically through the YD–Preboreal transition, with the development of high biological productivity and normal marine sedimentation since ∼11.4 cal. ka BP. The transition was more gradual on the eastern Kara Sea shelf submerging during the Early Holocene transgression. The Holocene time series in the Arctic seas document several millennial and centennial-scale events related to the variability of the Atlantic water input and NAO, including the Holocene thermal maximum, cooling at 8.2 cal. ka, Medieval Warm Period, Little Ice Age, and recent warming.