Pleistocene Sediments around South Georgia: archives for Antarctic Circumpolar Current dynamics and climate-induced signals in Sub-Antarctica (Past-ACC)

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The Antarctic Circumpolar Current (ACC) with its system of oceanographic fronts and bathymetrically deep-controlled outflow areas of dense and cold bottom water (AABW) make the Scotia Sea a particularly interesting area for surface and deep water paleoceanographic reconstruction. We want to study the dynamics and spatial variability of this frontal system during the last orbital climate cycle. The atmospheric and oceanographic current system transports dust from South America and together with ferrous minerals from South Georgia (SG) thereby fertilizing primary production. Multidisciplinary and multi-proxy investigations on sediment cores of drift deposits in the adjacent deep sea and on high-resolution shelf sediments will help to characterize relevant processes and amplitudes of natural climate changes. Nearshore and on the continental shelf, the extent of inland ice caps and glacial-marine glacier-affected sediments were mapped using multi-beam and sediment echo-sounders. High sediment deposits in some fjords and glacially eroded troughs have excellently archived the younger glacier behaviour and climatic changes. The SG ice cap is more sensitive to climatic changes than the much larger and more isolated Antarctic ice sheets, and is therefore an attractive target to study past climate variability in the Southern Hemisphere.