Towards a 3D-ecosystem model of the Baltic Sea

The paper describes briefly the preliminary results of a coupled chemical–biological and circulation model of the Baltic Sea. The chemical–biological model involves nine state variables to simulate the nitrogen cycle. A 1-year simulation shows how the model could be used to estimate budgets and nitrogen transports. The importance of shallow coastal areas for the removal of riverborne nitrogen is demonstrated on the Pomeranian Bight area. Within the simulation period, only 15% of the Oder river nitrogen load have left the Pomeranian Bight into the Baltic Sea.