The update of the coastal topo-bathymetric DEM of the Gironde estuary - downstream with a resolution of 0.0002° (~ 20 m) was carried out in the third phase of the HOMONIM project. This DEM covers the downstream part of the Gironde estuary, from Pauillac to its mouth. It is complementary to the DEM covering the upstream estuary. The DEM is intended to be implemented in hydrodynamic models in order to produce forecasts as accurate as possible of water heights and sea states at the coast to improve the relevance of the Wave-Submergence Vigilance. This product is available with either the Lowest Astronomic Tide (LAT) or the Mean Sea Level (MSL) as a vertical reference.

The update of the coastal topo-bathymetric DEM of the Pertuis charentais at a resolution of 0.0002° (~ 20 m) was carried out in the third phase of the HOMONIM project. The DEM extends from the terrestrial domain to about 60 meters depth over all the pertuis (pertuis Breton, pertuis d’Antioche and pertuis of Maumusson). The DEM is intended to be implemented in hydrodynamic models in order to produce forecasts as accurate as possible of water heights and sea states at the coast to improve the relevance of the Wave-Submergence Vigilance. This product is available with either the Lowest Astronomic Tide (LAT) or the Mean Sea Level (MSL) as a vertical reference.

The coastal topo- bathymetric DEM for the coasts of Morbihan with a resolution of 0.0002° (~ 20 m) was prepared as part of the TANDEM project (Programme Investissements d'Avenir, ANR-11-RSNR-00023-01). It covers the French administrative department of Morbihan and part of Loire-Atlantique. This DEM runs from the Gâvres peninsula in the north west to La Baule in the south east and covers the Gulf of Morbihan, the Quiberon bay and peninsula, Houat, Hoëdic and Belle-Ile islands and the Vilaine estuary. The DEM is designed to be implemented in the hydrodynamic models of the TANDEM project in order to estimate the coastal effects of tsunamis for the Atlantic and English Channel, where French nuclear power plants have been installed for about 30 years. This product is available with the Lowest Astronomic Tide (LAT) or the Mean Sea Level (MSL) as a vertical datum.

The bathymetric DEM for the coasts of Guadeloupe and Martinique with a resolution of 0.001° (~ 100 m) was prepared as part of the HOMONIM project. The DEM covers some of the Lesser Antilles islands, from Montserrat in the north to Sainte-Lucie in the south. The model ranges off-shore to a depth of 5800 m. 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.

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).

The bathymetric DEM for the coasts of Guadeloupe and Martinique with a resolution of 0.001° (~ 100 m) was prepared as part of the HOMONIM project. The DEM covers some of the Lesser Antilles islands, from Anguilla in the north to Saba in the south. The model ranges off-shore to a depth of 3275 m. 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.

The bathymetric DEM for the coasts of Corsica with a resolution of 0.001° (~ 100 m) was prepared as part of the HOMONIM project. It covers the entire Corsican margin. The model ranges off-shore to a depth of 3000 m. 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.

The bathymetric DEM for the coasts of New-Caledonia with a resolution of 0.001° (~ 100 m) was prepared in the framework of a Shom-IRD partnership as part of the TSUCAL project. The DEM covers the basin from New Caledonia in the west to the Vanuatu archipelago in the east. The DEM is designed to be used in hydrodynamic models in order to improve the pertinence of the Waves-Submersion monitoring programme.

The coastal topo-bathymetric DTM of the Arcachon basin and its surroundings at a resolution of 0.0002° (~ 20 m) was produced as part of the HOMONIM project. The DTM covers the coastline of a part of the Gironde department, from the Carcans and Hourtin ponds in the North, to the Cazaux and Sanguinet lakes in the South. It covers the entire Arcachon basin and extends offshore to about 40 m depth. The DTM is intended to be implemented in hydrodynamic models in order to produce accurate forecasts of water heights and sea states at the coast and to improve the French storm surge warning system. This product is available with the Lowest Astronomic Tide (LAT) or with the Mean Sea Level (MSL) as a vertical datum.

The coastal topo-bathymetric DEM was produced using the bathymetric and topographic data acquired between 2012 and 2015 by Shom and the PASSION programme team. The 20 m coastal grid covers the Passion atoll – Clipperton and the local flanks of the atoll to a depth of 1500 m. Passion island - Clipperton, in the eastern Pacific Ocean, is a remote uninhabited atoll over 5,000 km from Tahiti in French Polynesia and over 1,000 km from the Mexican coasts. Passion island is the highest point on the Clipperton ridge, and the only location above water level. This is the only coral atoll in the eastern Pacific in the northern hemisphere, at a longitude of W 109° and a latitude of N 10°.