Numerical simulations of sediment drift evolution to reconstruct current conditions and sediment transport mechanisms under fundamentally different extreme polar climate situations adopting high-resolution records from ODP Leg 178, offshore the Antarctic

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To gain a detailed understanding of the temporal and spatial evolution of the Antarctic Peninsula drifts, extensive numerical process simulations are essential to reconstruct the geological as well as oceanographic framework over long-time periods during the Neogene. This project will be directly connected to the IODP initiative - extreme climates. Numerical models enable a wide spectrum of scenarios to be tested, specifically to evaluate (a) current conditions and (b) sediment input variations in space and time for sediment transport processes in particular to quantify the along-slope vs. down-slope component. Accordingly, simulations obtain detailed information about past oceanic circulation and environmental conditions to identify climate shifts. However, sediment physics as well as erosion and deposition criteria are only partially implemented in ocean circulation models. Thus, this project focuses on two major aspects: (I) improvement of the sediment transport module in ROMS (Regional Ocean Circulation Model) and (II) development of a high-resolution 3D forward model to investigate the evolution of Drift 7. We have selected the area of OOP Leg 178, because a dense grid of seismic profiles and numerous high-resolution cores document extreme climate episodes. These considerable sedimentological and geophysical data supply information about: (a) event horizons, (b) seismostratigraphic unit thicknesses, (c) grain-size distributions within seismostratigraphic units, and (d) physical properties of sediments at event horizons and will serve as an excellent model input.