Climate System: Studies in the Climate System focus on the coupled lithosphere-ocean-ice-atmosphere system and its importance for the world climate. Long-term tectonic changes have shaped the morphology of ocean basins, their margins and the continents and provide the geometric basis for ocean and atmospheric circulation during various climate stages. Detailed reconstructions of palaeobathymetry at significant geological epochs will improve constraints on simulations of past regional and global ocean circulation. Ocean and atmosphere dynamics provide the stage on which feedbacks with the biosphere take place and define past and future climate evolution. AWI researchers conduct surveys and numerical simulations related to ocean circulation, transport of material and energy in the polar seas and the polar atmosphere, and to the influence of these processes on the global climate system. An important focus is placed on climate modelling and the statistical analysis of palaeoclimate data derived from marine sediments and polar ice cores, which provide a wealth of data on past ocean temperature changes, atmospheric circulation, and effects on biogeochemical cycles.