The purpose for this dataset is to offer full coverage with a 50m x 50m grid in the sea in areas near to the Norwegian coast. Note that differing degrees of interpolation have been used; as a consequence of this, the datasets have a varying quality and reliability.

The Norwegian Mapping Authority also offers 50m x 50m grids (terrain models at sea) with a higher quality and a greater reliability with regard to depths.

This dataset has limited coverage for near-coastal areas and the adjacent sea areas.

The recommended areas for use of this type of data are: overview planning, coarse models, illustrations, etc.; and also in connection with research, coastal zone planning, environmental monitoring, geological surveys, habitat mapping, development, offshore operations, etc.

The data is not approved for navigational purposes.

Not approved for navigation. Not suitable for detailed planning or similar uses.

The datasets are based on depth data from the Hydrographic Service's primary database. Depth points and shoals have been triangulated to a TIN model (triangulated irregular network), taking into account both the position and depth. The TIN model has also been used to interpolate depth values with a spacing of every 25 meters. The dataset has also been modelled with linear distance weighting, cropped to land and unsurveyed areas, and compiled into regular grids with a resolution of 50m x 50m.

The depth data from the primary database is of varying quality and resolution. The data for coastal areas is considerably better than further out in the ocean. Generally, local variations will also occur as a consequence of differences in the source of the data. Positioning accuracy varies depending on depth and terrain variations, and on the equipment and methodology which was used during the hydrographic surveys.

Note that varying degrees of interpolation have also been used when generating the datasets.

If you need assistance in downloading or using the Hydrographic Service's data or services, questions and inquiries can be sent to our Customer Service Center: kundesenter@kartverket.no, tel.: +47 32 11 80 00 kundesenter@kartverket.no If you need assistance in downloading or using the Hydrographic Service's data or services, questions and inquiries can be sent to our Customer Service Center: kundesenter@kartverket.no, tel.: +47 32 11 80 00

cellevis

The datasets are based on depth data from the Hydrographic Service's primary database. Depth points and shoals have been triangulated to a TIN model (triangulated irregular network), while preserving the positions and depths. The TIN model has also been used to interpolate depth values with a spacing of every 25 meters. The dataset has also been modelled with linear distance weighting, cropped to land and unsurveyed areas, and compiled into regular grids with a resolution of 50m x 50m. The datasets are based on depth data from the Hydrographic Service's primary database. Depth points and shoals have been triangulated to a TIN model (triangulated irregular network), taking into account both the position and depth. The TIN model has also been used to interpolate depth values with a spacing of every 25 meters. The dataset has also been modelled with linear distance weighting, cropped to land and unsurveyed areas, and compiled into regular grids with a resolution of 50m x 50m. The depth data from the primary database is of varying quality and resolution. The data for coastal areas is considerably better than further out in the ocean. Generally, local variations will also occur as a consequence of differences in the source of the data. Positioning accuracy varies depending on depth and terrain variations, and on the equipment and methodology which was used during the hydrographic surveys. Note that varying degrees of interpolation have also been used when generating the datasets.

ISO19115

2003