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

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 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.

Geographic information layer including the Saline limit of waters - mainland France, French Guiana, Martinique and Guadeloupe. This layer must be considered as an initial version to be validated locally by the competent services. Shom actively seeks out any information which could complete and improve the precision of this layer. The streams and rivers listed correspond to those mentioned in the applicable regulations and/or by a competent Government service. An inventory of existing legal and geographic information was drawn up prior to production in the form of an enquiry targeting services during the second half of 2014. The source legal text and a summary of digital conversion processes is available for each boundary proposed.Updated july 2018

The georeferenced digital image solution for the nautical chart is a digital conversion of the corresponding printed nautical chart produced by Shom or its legends, with georeferencing indications and including miscellaneous text.

Shom is the national referent for the level of the sea in situ on all areas under French jurisdiction. In this capacity, he assures under the acronym REFMAR different coordination functions in the collection and dissemination of public data related to water level observations, in order to promote their use in multiple applications within the framework of international recommendations.

Geographic information layer including the Limit of maritime affairs - mainland France, French Guiana, Martinique and Guadeloupe. This layer must be considered as an initial version to be validated locally by the competent services. Shom actively seeks out any information which could complete and improve the precision of this layer. The streams and rivers listed correspond to those mentioned in the applicable regulations and/or by a competent Government service. An inventory of existing legal and geographic information was drawn up prior to production in the form of an enquiry targeting services during the second half of 2014. The source legal text and a summary of digital conversion processes is available for each boundary proposed.Updated july 2018

The "Sovereignty and jurisdiction maritime spaces of France" product contains the areas of sovereignty and jurisdiction maritime spaces of France all around the world.<br /><br /> It is constituted of 2D areas objects split into four categories :<br /> - the territorial sea (from baselines to a distance of 12 nautical miles or to maritime boundaries with neighbouring countries);<br /> - the contiguous zone (from 12 nautical miles to 24 nautical miles from the baselines or to maritime boundaries with neighbouring countries);<br /> - the exclusive economic zone (EEZ) (from 12 nautical miles to 200 nautical miles from the baselines or to maritime boundaries with neighbouring countries);<br /> - the continental shelf over the 200 nautical miles limit (from 200 nautical miles from the baselines to the limits recommended by the Commission on the Limits of the Continental Shelf (CLCS) or to the maritime boundaries with neighbouring countries).<br /> Internal waters, which constitute a space of sovereignty beyond the baselines, are not included in the "Sovereignty and jurisdiction maritime spaces of France" product.<br /> The "Sovereignty and jurisdiction maritime spaces of France" product may not be considered as an enforceable right. Only the “Maritime limits and boundaries” product, that can be displayed and interrogated on the website data.shom.fr (maritime boundaries category) and also downloaded on the French national portal of maritime limits (https://maritimelimits.gouv.fr), may be considered so.<br /><br /> December 2022 version.

"Regulation - Navigation" product contains 18 object classes, the acronyms used are those of IHO standard S-57 - International Hydrographic Organization – (https://iho.int/): - Anchorage area (ACHARE): an area in which vessels anchor or may anchor. - Anchor berth (ACHBRT): a designated area of water where a single vessel, sea plane, etc. may anchor. - Administration Area (Named) (ADMARE) - Cable area (CBLARE) - Coastguard station (CGUSTA) - Cargo transhipment area (CTSARE) - Distance mark (DISMAR): mark indicating the distance on canals or rivers. - Dumping ground (DMPGRD): sea area where dredged material or other potentially more harmful material e.g. explosives, chemical waste, is deliberately deposited. - Fairway (FAIRWY): part of a river, harbour etc. where the main navigable channel for vessels of larger size lies. It is also the usual course followed by vessels entering or leaving harbours and sometimes called "ship channel". - Ice area (over land or water) (ICEARE) - Local magnetic anomaly (LOCMAG): anomaly of the magnetic field of the earth, extending over a relatively small area, due to local magnetic influences. - Marine farm/culture (MARCUL) - Navigation line (NAVLNE): a line generally passing through two clearly defined charted landmarks, and along part of which a vessel can approach safely. - Pipeline area (PIPARE) - Recommended track (RECTRC): track of undefined width, recommended to all or only certain vessels. - Restricted area (RESARE): specified area designated by an appropriate authority within which navigation is restricted in accordance with certain specified conditions. - Sea-plane landing area (SPLARE) Detailed definitions of each of these object classes can be found in the S-57 standard (https://iho.int/en/standards-and-specifications). An online catalog is available at http://www.s-57.com/. Some of the symbols used for display on data.shom.fr portal have been adapted from icons from the OpenSeaMap open library (https://github.com/OpenNauticalChart/). For reasons of readability, not all the characteristics of the objects are systematically displayed. All available information can be consulted by querying this layer.

In accordance with decree no. n°2019-165 of 5 March 2019, Shom measures and updates maritime altimetric datums or hydrographic datums for French ports in mainland France and overseas administrative departments and authorities. These datums are provided to allow for standardisation based on legal altimetric datum systems (e.g. IGN69). Shom also disseminates typical tide figures for each port (lowest tide, mean tide, etc.). The Marine Altimetric Reference Value (RAM) product is available for ports in mainland France and for overseas territories with a tidal observatory.