Modelling and feedbacks

Modelling of global biogeochemical cycles aims at achieving an understanding of diverse feedbacks between element fluxes, biological activity and ocean circulation. A special focus is set at feedbacks between climate change (for the present and the past) and the carbon cycle, the role of dissolved iron for the primary production of the Southern Ocean and the impact of physiological adaptations of phytoplankton to the environmental conditions. For this we use an ecosystem model describing changes in phytoplankton physiology by changing the intracellular elemental ratios. In addition, the model tries to describe in more details the complex chemistry of iron in seawater. This model is coupled to global or regional physical ocean circulation models in order to calculate the distribution of crucial parameters in the ocean. To this end, we use the Finite-Elemente Sea- ice Ocean Model (FESOM) that is being developed at the AWI.