Eastern Fram Strait Palaeo-archive (FRAME): IODP Proposal 985-Full 2

The North Atlantic-Arctic Oceans are unquestionably major players in the climatic evolution of the Northern Hemisphere and in the history of the meridional overturning circulation of the Atlantic Ocean. The establishment of the modern North Atlantic Water has been indicated as one of the main forcing mechanisms for the onset of the North Hemisphere Glaciation. North Atlantic Water control the extent and dynamics of circum-Arctic and circum-North Atlantic ice sheets and sea ice in addition to deep water and brine production. How the ocean system and cryosphere worked during past warmer intervals of either/both high insulation and/or high atmospheric CO2 content, is still unknown and debated. The required information can only be attained by offshore scientific drilling in high-resolution, continuous and undisturbed sedimentary sequences at the eastern Fram Strait along the main pathway and northern penetration of the North Atlantic Water flowing into the Arctic Ocean. As a matter of fact, this area around Svalbard can be considered as a “sentinel of climate change”. The reconstruction of the dynamic history of the paleo Svalbard-Barents Sea Ice Sheet, is important as it is considered the best available analogue to the West Antarctic Ice Sheet (WAIS), whose loss of stability is presently the major uncertainty in projecting future global sea level in response to the present global climate warming induced by the anthropogenic rising of atmospheric CO2 content. The lack of a robust marine sediment chronostratigraphy, caused by low and variable sedimentation rates on Arctic ridges and variable calcareous microfossil abundance due to low productivity and/or poor preservation, hampers a proper understanding of the past Arctic climate evolution. Moreover, limited or equivocal oxygen isotope stratigraphy and magnetostratigraphy represent major impediments. Potential high-resolution marine records from continental shelves and/or upper slopes rarely extend beyond the last glaciation and/or contain stratigraphic discontinuities related to ice sheet dynamics on the shelves and sediment dynamics on the slopes. IODP Full-085 proposal is motivated by the necessity of retrieving long and inter-connected sedimentary records along the eastern side of the Fram Strait in order to establish a robust chronostratigraphy, and to improve our understanding of the boundary conditions and forcing mechanisms determining the evolution of the Northern North Atlantic and Arctic regions and their past and present connections with global climate.