c:/dev/skygeo/src/iso2stac/stac_output_dynamic/catalog.json
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c:/dev/skygeo/src/iso2stac/stac_output_dynamic/collection-norwegian_mapping_authority/collection.json
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c:/dev/skygeo/src/iso2stac/stac_output_dynamic/collection-norwegian_mapping_authority/7e6d474f-337e-410a-9c19-d74fac9143e4/7e6d474f-337e-410a-9c19-d74fac9143e4.json
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c:/dev/skygeo/src/iso2stac/stac_output_dynamic/collection-norwegian_mapping_authority/collection.json
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separasjonsmodell oceans
Current version: 2025a. New versions will be published as the underlying dataset is
improved. The model gives the vertical separation between chart datum and the ellipsoid
(EUREF89) on a regular geographic grid (0.005° × 0.01°), covering the coastal region of
mainland Norway.

Chart datum (CD) is defined via Lowest Astronomical Tide (LAT). North of Utsira/Karmsundet
CD is identical to LAT. From Utsira to the Swedish border CD is 20cm below LAT, and in the
inner parts of the Oslo fjord, CD is 30cm below LAT.

The model is a combination of the models for Mean sea level above the ellipsoid and Mean
sea level above chart datum, so the quality depends on those two models.

An estimate of the standard deviation of the model is included as a separate band in the GeoTIFF file. When selecting the bin-format, one gets a separate file with the gridded standard deviation.
Chart datum above ellipsoid