Towards the time dependent modeling of sediment core data on a global basis

The procedure for the simulation of a time dependent sediment stratigraphy for 4 different sediment species with a global biogeochemical ocean general circulation model is presented, In this feasibility study, a sediment colu mn for the last 131 kyr was accumulated through use of a variable ocean vel ocity field (mixed from preindustrial and glacial ocean time slices in a ki nematic approach). The biogenic components of sediment are entirely a model product. Artificial sediment cores were "recovered" from the simulated str atigraphy. The approach is the foundation for a systematic comparison of pa leoclimate simulations with the sediment record. Through use of adjoint mod el codes the direct 4-dimensional data assimilation of paleoclimate observa tions will become possible in the long range.