Bathymetry of the Tyrrhenian Sea and surroundings. The first contour line available is 200 m, which restricts this product to low resolution applications (e.g. calculation of surge level) but not for local applications (e.g. modelling of long-shore currents)

Data description

The bathymetric layer depicts the following isobaths: 200m, 500, 1000m, 1500m, 2000m, 2500m, 3000m, 3500m, 4000m, 4500m, and 5000m. Data are provided as a GIS polyline.

Source of data

Isobaths are extracted from the GEneral Bathymetric Chart of the Oceans (GEBCO) gathered and distributed by the British Oceanographic Data Centre, on behalf of the International Oceanographic Commission.


GEBCO represents a European-wide unified dataset, derived from a collection of existing maritime sheets and atlases. However, GEBCO does not ensure the same level of details for all European waters: depending on the areas, not all the isobaths are represented and not with the same accuracy.

Quality GEBCO has been designed for illustrative purpose and for low resolution modelling. Its nominal scale is 1:1,000,000, which is not suitable for applications at scale 1:100,000. However, it is worth mentioning that GEBCO is currently the only product featuring bathymetry in vector format and available for all European waters. Its quality is being regularly improved by the British Oceanographic Data Centre.
Copyright and data access conditions The dataset is copyrighted (BODC). Licence fees for accessing the complete database in vector format is about 250 £. It is however possible to freely disseminate GEBCO data in raster format (e.g. .bmp, .jpg, .gif). Only the mention of GEBCO copyright is then required. Contractually the BODC insists to
communicate that "Data from the GEBCO Digital Atlas are not to be used for navigation or for any other purpose relating to safety at sea".