Abstract
The presence of the sea ice diatom biomarker IP25 in Arctic marine sediments has been used in previous studies as a proxy for past spring sea ice occurrence and as an indicator of wider palaeoenvironmental conditions for different regions of the Arctic over various timescales. The current study will (1) briefly describe the sea ice conditions of northern Norway for the interval ca 13.8 - 7.2 cal ka BP and (2) mainly focus on a different study around the East Greenland-North Iceland area (Denmark Strait), during the ca last 140 yr. The Denmark Strait area is a critical region due to the interaction between the polar and subpolar climate systems. On the Greenland side of the strait the conditions are severe with a 8 ? 10 month sea ice cover, with numerous tidewater glacier margins injecting icebergs into the fjords and adjacent shelf. Unexpectedly, abundances of marine biomarkers such as IP25 were remarkably low compared to other Arctic regions (e.g. Canadian Arctic, Fram Strait) that also experience severe sea ice conditions. A possible theory for explaining such a scenario will be presented, together with mineralogical data (e.g. ice rafted debris (IRD), quartz/feldspar hematite stained grains (HSG)) as well as observational data (e.g. storis) acquired during this period.