EMOSEM Final Report - Ecosystem Models as Support to Eutrophication Management In the North Atlantic Ocean

One of the leading challenges in marine science and governance is to improve scientific guidance of management measures to mitigate eutrophication nuisances in the EU seas. Too few approaches integrate the eutrophication process in space (continuum river-ocean) and in time (past, present and future status). A strong need remains for (i) knowledge/identification of all the processes that control eutrophication and its consequences, (ii) consistent and harmonized reference levels assigned to each eutrophication-related indicator, (iii) identification of the main rivers directly or indirectly responsible for eutrophication nuisances in specific areas, (iv) an integrated transboundary approach and (v) realistic short term and long term nutrient reduction scenarios. As a step in this direction (ou in agreement), the main objective of EMoSEM was to link the eutrophication nuisances in specific marine regions of the North-East Atlantic (NEA) to river anthropogenic inputs, trace back their sources up to the watersheds, then test nutrient reduction options that might be implemented in these watersheds and propose consistent indicators and reference levels to assess Good Environmental Status (GEnS). To achieve this objective, the state-of-the-art modelling tools describing the river-ocean continuum in the NEA continental seas have been developed and combined. Three marine ecological models (B IOPCOMS , E CO - MARS 3D, M IRO & CO ) have been adapted and coupled to a newly developed generic ecological model for European river-basins (PyNuts-Riverstrahler). The modelling tools have been validated against observations. Numerical methods have been included in the marine models to track the origin of nutrients at sea from different sources (riverine, oceanic and atmospheric)...