The DTM is a compilation of multibeam echosounder surveys acquired in 2013. The resolution is 1/64 arc-minutes (~30m). Surveys are located on the Capbreton Submarine Canyon (France) with depths from -4.7m to -344.9m. Depths are referenced to the Lowest Astronomical Tide and the coordinates are expressed into the WGS84 reference frame. The surveys which compose the DTM are S201306500-09 and S201306500-11. Data and metadata associated to these surveys are available on the website http://diffusion.shom.fr/pro/lots-bathy.html. The DTM is not to be used for navigation.

The regional bathymetric Atlantic – Channel – North-Sea DTM has a resolution of 0.001° (~111m). Its geographic coverage includes the Bay of Biscay, the English Channel and a part of the North Sea. The DTM extends from the coast to the continental slope (about of 4800m deep). This DTM is produced in the framework of the HOMONIM project which aims at improving operational forecast capabilities for the national coastal flood warning system. This DTM is offered openly on the Shom diffusion website (http://diffusion.shom.fr/produits/bathymetrie/mnt-facade-atl-homonim.html). http://dx.doi.org/10.17183/MNT_ATL100m_HOMONIM_WGS84

These maps are prepared on the basis of vector-based mapping data (IHO S-57 format) including the detailed description of each object (beacons, wrecks, submarine cables, regulated zones, survey systems, etc.). These maps are the digital equivalent of printed nautical charts.

Tidal ranges on the French coasts of the Channel and the Atlantic for a coefficient of 95 : tidal range for mean neap tides for average atmospheric conditions..

The Tidal stream atlas netcdf product – The Bay of Biscay provides tidal current data for an area stretching from Brittany to the northern coast of Spain. The product consists of a unique gridded file with 2 km spatial resolution covering the Bay of Biscay. The U and V velocities of the tidal currents depend on the tidal conditions considered at mean neap and spring tidal rates. The data are provided in m/s for the surface layer. The times are given in relation to high tide at the reference port chosen in the area and are provided from 6 hours before to 6 hours after that reference.

The coastal topobathymetric DEM of Ré Island's surroundings, with a resolution of 0.00005° (~5 meters), was created by Shom as part of the HOMONIM-3 project. It covers the coast of the municipalities of Ars-en-Ré and Saint-Clément-des-Baleines, extending offshore to a depth of about 20 meters, to the west of the Phare des Baleines lighthouse. This DEM is designed for use in hydrodynamic models to enhance the modeling of coastal processes, particularly forecasting submersion risk. The product complements the coastal topobathymetric DEM of the Pertuis-Charentais, with a resolution of 0.0002° (~20 meters), and the bathymetric DEM of the Atlantic coast, with a resolution of 0.001° (~100 meters). It is available in the vertical reference of the Lowest Astronomical Tide (LAT) or the Mean Sea Level (MSL).

Litto3D provides 3D, continuous sea-land description of French coastal areas. Data is acquired by airborne topo-bathymetric LiDARs. Litto3D products come in 3D point clouds and digital terrain models formats. The product "Litto3D - Nouvelle-Aquitaine 2020-2022" covers the geographical area from the Charente-Maritime to the Spanish border. For the maritime part, the data produced by Shom extend offshore down to signal extinction, approximatively 20 depth when environmental conditions are optimal. On land, the data are truncated at a limit that ensures the product retain its coastal character.

The bathymetric DEM of the atlantic facade with a resolution of 0.001° (~ 100 m) was prepared as part of the HOMONIM project. It encompasses part of the North Sea, the Channel and the Bay of Biscay. Offshore, this DTM extends beyond the slope to approximately 4800 m depth. The DEM is designed to be used in hydrodynamic models in order to produce high-precision forecasts for coastal water levels and sea conditions and therefore improve the pertinence of the Waves-Submersion monitoring programme. This product is available with the Lowest Astronomic Tide (LAT) or the Mean Sea Level (MSL) as a vertical datum.

RasterMarine is a series of digital images taken from nautical charts, with no additions, legends or georeferencing information. The RasterMarine range is available at six sets of scales: - RasterMarine10 1:10,000 - RasterMarine25 1:25,000 - RasterMarine50 1:50,000 - RasterMarine100 1:100,000 - RasterMarine350 1:350,000 - RasterMarine1M 1:1,000,000. Unless exceptional circumstances apply, the RasterMarine range is updated on a weekly basis and the modified grid squares are re-published, replacing the previous versions. All corrections, publications, editions and suppressions with an effect on the reference nautical charts are taken into consideration. <br /> 24/09/2026 version <br />

Weather forecasting models are used to show atmospheric conditions by computing changes in meteorological parameters on a 3D atmospheric grid model. Physical laws are used to determine behaviour: fluid mechanics, variation in water phase, turbulence, radiation, and atmospheric interaction with space, the continents and the oceans. The initial conditions are determined by assimilating variational data including a large volume and wide variety of in situ observations obtained from remote detection systems. The weather forecasts available on data.shom.fr only contain "wind at 10m" and "atmospheric pressure at sea level" parameters. A land/sea mask is then applied to exclude non-maritime forecasts. These forecasts are taken from 2 different types of models: ARPEGE for world and European scale input (0.5° to 0.1° resolution) and AROME for mainland France (1.3 km resolution). ARPEGE is a global hydrostatic spectral model, with variable horizontal resolution (centred on France), vertical finite element modelling and hybrid vertical coordinates. ARPEGE is an integral part of the Arpège-IFS software package, designed, developed and maintained by Météo-France in cooperation with ECMWF (European Centre for Medium-Range Weather Forecasts - http://www.ecmwf.int/). AROME is a non-hydrostatic spectral model for weather forecasts in mainland France, with finite difference modelling for vertical input and hybrid coordinates. AROME was developed by Météo-France thanks to close national (CNRS) and international (CEPMMT, Aladin, Hirlam) cooperation programmes on the basis of the Méso-NH research model and the dynamic core of the Aladin model.