The SeaDataNet aggregated datasets over the Atlantic Ocean are regional ODV historical collections of all temperature and salinity measurements contained within SeaDataNet database and covering 3 European sea basins: North Arctic Ocean, North Sea, North Atlantic Ocean. Two versions have been published during SeaDataNet 2 and they represent a snapshot of the SeaDataNet database content at two different times: • V1.1 January 2014 • V2 March 2015 Each of them is the result of the Quality Check Strategy (QCS) implemented during SeaDataNet 2 that contributed to highly improve the quality of temperature and salinity data. The QCS is made by four main phases: 1. data harvesting from the central CDI 2. file and parameter aggregation 3. quality check analysis at regional level 4. analysis and correction of data anomalies. The aggregated datasets have been prepared and quality checked using ODV software.

SeaDataNet gridded climatologies are based on the SeaDataNet Temperature and Salinity historical data collection v1.1. For the Atlantic Ocean there are covering 2 European sea basins: North Arctic Ocean, and North Atlantic Ocean The preparation of the products has also improved the quality, the consistency and the overall coherence of the data made available by SeaDataNet. They have been computed using DIVA software.

Shom uses HYCOM 3D (Hybrid Coordinate Ocean Model) digital models to model changes to the ocean environment (currents, temperature, salinity, water depth). These HYCOM 3D models include a scalable (space and time) vertical grid, which is particularly suitable for the coastal regions and physical phenomena modelled (particularly the transition from a deep sea zone to the continental shelf, and the presence of frontal zones). These models were adapted to coastal models at Shom, particularly by integrating tides and the effects of rivers. These models focus on changes and variability in the different physical processes affecting coastal areas (continental shelves and slopes), such as tidal fronts, river plumes, tides and internal waves, upwelling and the dynamics of the mixed layer at an hourly frequency and with high spatial resolution (1/60 deg for the Biscay Channel model).

This annual statistics at 500m horizontal resolution was produced from the archived time series of MARS 3D physics model hindcast runs along French Atlantic Coast. The variable that is available here is Salinity. Values are expressed in psu. In each pixel the value is an average of the values of the 40 vertical levels that are considered in the model.

This annual statistics at 500m horizontal resolution was produced from the archived time series of MARS 3D physics model hindcast runs along French Atlantic Coast. The variable that is available here is the Salinity. Values are expressed in psu. The vertical level is the seabed.

This annual statistics at 500m horizontal resolution was produced from the archived time series of MARS 3D physics model hindcast runs along French Atlantic Coast. The variable that is available here is the Salinity. Values are expressed in psu. The vertical level is the sea surface.