CURAE – bridging the gap between regional CMEMS forecasts and coastal high-resolution applications

The sustainable management of coastal areas with limited natural resources and subject to high anthropogenic pressures, based on complete forecast and analysis systems, is one of the main concerns of coastal authorities. Paradoxically, current oceanographic operational predictions are often insufficient to provide a good description of these regions due to low resolution/accuracy, the omission of relevant land-sea interactions, and the inadequate inclusion in the models of physical processes specific to the coastal fringe.

The CURAE project bridges this gap between the regional scales and the local coastal needs by establishing a 2-way connection between the existing CMEMS products and an innovative coastal information system (required by coastal water managers and littoral users alike) that considers hydro-morphodynamic interactions in an operational manner. The paper will present a new set of robust downscaling and coupling tools that have been developed to enhance the coastal dimension of present CMEMS products. The main advances refer to coastal processes not commonly incorporated in oceanographic predictions and that interact with the shelf sea, including the continental discharge in terms of water, sediment and nutrient fluxes.

The project is focused on two hydrodynamically contrasting sites with different uses (aquaculture and dredging) that demonstrate the added value and potential of CMEMS for coastal applications. The first case is the semi-enclosed microtidal Fangar Bay in the Ebro Delta (Spanish Mediterranean), in which bivalve farming coexists with tourism and nutrient- and sediment-laden freshwater discharges from rice fields in a hydrodynamically weak environment interacting with active domain geometries. The second study case is the macrotidal Wadden Sea/German Bight estuaries area, with concentrated plus distributed land discharge and significant dredging activities required for port operations. To ensure that the tools and conclusions derived from the project are as generic as possible, different numerical approaches (structured vs. unstructured grids) have been applied at each site and will be compared and discussed in the paper. The obtained results illustrate the benefits of quantitative forecasts for the healthy functioning of coastal systems, while proving the potential of CMEMS for supporting sustainable interventions in the coastal zone. The obtained advances are encouraging from scientific and application standpoints and underpin the need for a high-resolution coastal extension of CMEMS.