Development of the Modeling System ICON-Coast
Theme A makes extensive use of the new ICON ESM (Icosahedral non-hydrostatic general circulation Earth System Model), arguably the most modern comprehensive Earth system model (ESM) worldwide. This new model allows the numerical simulation of all space scales within a single modeling framework and a much more efficient use of high-performance (massively parallel) computing systems at the DKRZ than possible with previous models. A great success of project A5 is the development of a new global ocean-biogeochemistry model based on ICON with the capacity to resolve processes in the land-ocean transition zone (Logemann et al., 2020, Mathis et al., in revision). Shelf-specific processes, specifically the benthic-pelagic coupling has been implemented, and the model is now able to capture the seasonal cycle in sea surface pCO2 and a number of shelf-specific phenomena, which before were not resolved in global ESMs. First results provide insight on the importance of internal dynamics and internally triggered delay and transformation mechanisms for external consequences (CO2-fluxes, carbon uptake).