Biomarker distribution of sediment core PS93/006-1@en

The northeastern Fram Strait at the entrance to the Arctic Ocean represents a key observatory for sea ice reconstructions as it sensitively reacts to environmental changes. A combined biomarker approach (HBIs, sterols, alkenones) was carried out on Core PS93/006-1 from the western Svalbard margin to reconstruct sea ice conditions related to glacial-interglacial cycles of the last 190 ka. The continuous presence of sea ice demonstrates the strong influence of the East Greenland Current in the eastern Fram Strait. Glacial intervals are characterised by extended sea ice conditions with perennial sea ice cover during early MIS 6, the Penultimate Glacial Maximum, the interstadial MIS 5d, MIS 4 and the Last Glacial Maximum. Less severe, yet highly variable, sea ice conditions with more frequent summer melt dominated the interglacial stages. By comparison with previous sea ice reconstructions along the western and northern continental margin of Svalbard, the highly variable impact of different environmental forces (i.e., ice sheet activity, Atlantic Water inflow) could be revealed.