BLUE2 for D5
Excess inputs of nitrogen and phosphorus from rivers contribute to eutrophication in European seas, with consequences for ecosystem functioning and sustainability. Here we use a pan European numerical ocean...
The Blue2MF is a comprehensive suite of modelling tools, developed by the JRC's D2 Ocean and Water Unit. This framework encompasses a variety of models designed to simulate and evaluate European Union marine ecosystems comprehensively across diverse management and policy scenarios. It covers the Mediterranean Sea, Baltic Sea, North Sea, Bay of Biscay and Iberian coast and Black Sea. It includes the following set of models:
Land-use models
The land-use model is CAPRI, a global agro-economic model used to assess impacts of agricultural, trade and environmental policies on the agricultural sector. This module depicts the spatial and temporal aspects of agricultural practices e.g., the evolution of nutrients from mineral fertilizer, manure and crop fixation impacting land and freshwater-marine environments.
Hydrological models
These models simulate the freshwater conditions of EU rivers and lakes regarding their quality (nutrient concentration) and quantity (water flow). More specifically, the freshwater nutrient levels are computed by the Geospatial Regression Equation for European Nutrient losses (GREEN) hydrological model. GREEN includes a geospatial data model for Europe, where data are linked to the hydrological structure of the river network to model nitrogen and phosphorus flow in the river basin according to different pathways. Europe is divided into c.a. 1 million catchments of 7 km2 average size. In complement, GREEN incorporates the freshwater flux from the LISFLOOD model. The freshwater flux and nutrient loads at the land / sea interface are used as inputs by the hydrodynamic and biogeochemical ocean model.
Hydrodynamic and biogeochemical models
The hydrodynamic component of Blue2MF is the General Estuarine Transport Model (GETM) that simulates marine water dynamics (current, temperature, salinity), permitting a realistic description of each EU seas in a 3D manner. The biogeochemical module, tailor fitted for the characteristics of each basin, simulates nutrient transport and fate within the planktonic food web.
Lagrangian model
LTRANS-ZLev model is used to simulate the dispersion, accumulation and beaching of floating inert particles, such as plastic debris, within marine environments.
High Trophic Levels (HTL) Model
Also known as ecosystem models, these assess the dynamics of marine organisms, ranging from phytoplankton to top predators, including fisheries. The HTL is simulated using Ecopath with Ecosim (EwE) which captures the structure and the dynamics of the marine food webs. A specific configuration is set up for each EU region (the Mediterranean Sea and the Black Sea). The HTL component uses the physical (i.e., temperature, salinity) and biogeochemical (i.e., phytoplankton biomass) fields generated by the coupled hydrodynamic-biogeochemical model.
Each of the modelled EU marine regions has a tailored setup and different spatial resolutions to account for specific characteristics of the marine ecosystems. The external forcing and conditions (e.g., the atmospheric conditions) are identical to all models to ensure consistency in scenarios testing.
By integrating key physical, chemical, and biological components across diverse management and policy scenarios, Blue2MF provides essential support for informed policy decisions. Its practical applications have included:
- evaluating the effects of water scarcity on marine ecosystems and its implications for the blue economy
- examining the impact of macrolitter on megafauna
- investigating the consequences of eutrophication on EU marine ecosystems
These outcomes are pivotal in underpinning essential EU policies and strategies aligned with the "source to sea" approach. This approach emphasises the interconnectedness of terrestrial, freshwater, and marine environments, promoting holistic management and conservation efforts.
The Blue2 Modelling Framework supports key EU environmental policies, notably including:
- Water Resilience Strategy
- Ocean Pact
- Marine Strategy Framework Directive
- Biodiversity Strategy
- Water Framework Directive
- Zero Pollution Action Plan
Additionally, the framework may contribute to Maritime Spatial Planning Directive and the Common Fisheries Policy.
Explore further
Effects of sea ice on Baltic Sea eutrophication indicators
This study investigates the influence of sea ice on eutrophication in the Baltic Sea ecosystem by comparing simulations from 1953 to 2017, with ice and without ice cover. We assessed the impact…
