Bathymetry is the underwater equivalent to hypsometry or topography. Bathymetric (or hydrographic) charts are typically produced to support safety of surface or sub-surface navigation, and usually show seafloor relief or terrain as contour lines (called depth contours or isobaths).
Bathymetry is a static data layer providing general indications of water depth in a particular area.
The EMODnet data products are based on the continuous average depth grid of one-sixteenth arc-minute. This grid is based on three source types: Individual bathymetric surveys, composite digital terrain data (cDTM) and Satellite-Derived Bathymetry. The latter two have been used whenever the actual survey data was unavailable for direct processing by the EMODnet partners. Whenever data were unavailable GEBCO data has been used to fill in the gaps.