The modelling of ecosystem processes in the Gulf of Finland

. The aim of this work was to introduce the last version of the hydrodynamic–ecosystem model FinEst and to supplement this model to enable its easy application for local areas. Complications in the case of local areas appear in the treatment of initial and open boundary conditions. This paper demonstrates how to handle the open boundaries and the initial data using a multi-step scheme of calculations in the Baltic Sea. First the model was applied for the entire Baltic Sea. Then the results of these calculations were used for the Gulf of Finland (GOF). Finally, calculations for some local areas in the GOF were made using the initial and open boundary conditions from the results of the GOF calculations.