This product includes Shom 3D digital data on tidal currents in the area "Loire" in shapefile and geotiff formats. These digital files provide information on tidal current components (speed and direction) on an hourly basis (6 hours either side of high water for a reference port), and for two typical tidal coefficients (45 and 95). Brest is taken as the reference port. Four layers are available: Surface; mid-depth; - 10 m above the sea bed and sea-bed.

In the absence of a maritime boundary agreement with a neighbouring State, the French Republic can unilateraly claim a delimitation. This boundary has indeed a provisional aspect pending the ratification of a boundary agreement. The theme "Maritime limits unilaterally claimed" gathers those limits unilaterally claimed by France. Some of those elkements are published by decree.

Compilation of marine gravity surveys acquired in the Northeast Atlantic by Shom between 2001 and 2016. These surveys were compiled to perform a quantification of the error of the gravity anomaly models derived from satellite altimetry. This dataset represents more than 22,000 measurement points distributed in 9 ascii survey files sampled at 1 kilometer. The file’s format is as follows: longitude latitude Gravity_anomaly error line_label.

The combined error grid of the SIO V31 gravity anomaly model (D. T. Sandwell, H. Harper, B. Tozer et al., Gravity field recovery from geodetic altimeter missions, Advances in Space Research, https://doi.org/10.1016/j.asr.2019.09.011) is computed with a method described in a paper submitted to Earth and Space Science (AGU). The model’s extension is North Atlantic.

This product includes Shom 3D digital data on tidal currents in the area "Loire" in shapefile and geotiff formats. These digital files provide information on tidal current components (speed and direction) on an hourly basis (6 hours either side of high water for a reference port), and for two typical tidal coefficients (45 and 95). Saint-Nazaire is taken as the reference port. Three layers are available: Surface; mid-depth; and sea-bed.

Compilation of marine gravity surveys acquired in the Northeast Atlantic by Shom between 2001 and 2016. These surveys were compiled to perform a quantification of the error of the gravity anomaly models derived from satellite altimetry. This dataset represents more than 22,000 measurement points distributed in 9 ascii survey files sampled at 1 kilometer. The file’s format is as follows: longitude latitude Gravity_anomaly error line_label.

This study provides an initial global estimate of the extreme water level values along the French metropolitan coastline. These results are to be refined locally with all available data and knowledge. The method used is based on a statistical analysis of the tide gauge observations available in the ports. It does not take into account wave observations. The results between ports are obtained by an interpolation method. The study produces at the reference ports the statistical estimates: - extreme values of high water surge in the Channel and Atlantic; - extreme values of water level for the whole of Metropolitan France. And a set of statistical estimation maps of extreme water level values along the coastline. The estimates provided go up to the 1,000-year return period. In view of the duration of observations used at the ports, the user must check whether estimates with a return period of more than 50 or 100 years are still valid 50 or 100 years still make sense.

Bathymetric datasets are an extraction of surveys belonging to the Shom public database. For depth up to 50m, the vertical precision of soundings varies from 30cm to 1m and the horizontal precision varies from 1 to 20m. In deep ocean, the vertical precision is mainly around 1 or 2% of the bottom depth. It is sometimes more, it depends on the technology used. The data are referenced to ZH which is assimilated to LAT. Data are corrected for sound velocity variations. <br /> October 27 2025 version

The combined error grid of the SIO V31 gravity anomaly model (D. T. Sandwell, H. Harper, B. Tozer et al., Gravity field recovery from geodetic altimeter missions, Advances in Space Research, https://doi.org/10.1016/j.asr.2019.09.011) is computed with a method described in a paper submitted to Earth and Space Science (AGU). The model’s extension is North Atlantic.

This study provides an initial global estimate of the extreme water level values along the French metropolitan coastline. These results are to be refined locally with all available data and knowledge. The method used is based on a statistical analysis of the tide gauge observations available in the ports. It does not take into account wave observations. The results between ports are obtained by an interpolation method. The study produces at the reference ports the statistical estimates: - extreme values of high water surge in the Channel and Atlantic; - extreme values of water level for the whole of Metropolitan France. And a set of statistical estimation maps of extreme water level values along the coastline. The estimates provided go up to the 1,000-year return period. In view of the duration of observations used at the ports, the user must check whether estimates with a return period of more than 50 or 100 years are still valid 50 or 100 years still make sense.