Denmark layer : with Greenland charts

October 2017

Peio

131 charts (197 including insets) have been added for Greenland in the Denmark (DGA) layer of the GeoGarage platform.

-> see GR list & corrections

These raster charts issued from scanned sources of paper maps come directly from Danish Geodata Agency (DGA), in charge of all the official nautical documentation published in Denmark.

The original files were digitally processed by the GeoGarage to adapt the different pixel resolutions between the scanned maps and also the different original local datum and projections to Mercator/WGS84.

Note : precautions in using navigational charts in Greenland waters

  • INCORRECT POSITIONING OF TOPOGRAPHY AND HYDROGRAPHY IN THE GEOGRAPHIC NET.
  • A MAJOR DIFFICULTY WITH THE PAPER CHARTS AVAILABLE FOR GREENLAND WATERS IS THE INCORRECT POSITIONING OF THE COASTLINE IN THE GEOGRAPHIC NET IN THE CHARTS.
  • AT THE NORTHERN AND EASTERN COASTLINES WHERE THE UNCERTAINTY IS MOST DISTINCT, THE COASTLINE MAY BE POSITIONED SEVERAL NAUTICAL MILES INCORRECT.
  • IN OTHER PARTS OF GREENLAND, THE UNCERTAINTY MAY BE LESS, BUT STILL AT A SUBSTANTIVE LEVEL WHEN COMPARING WITH THE ACCURATE POSITION ACHIEVABLE FROM A GNSS RECEIVER.
  • IN GENERAL, CHARTS OF THE NORTHERN AND EASTERN GREENLAND COASTLINES ARE MISPLACED BY 0-5,000 METRES, AND IN SOME AREAS OF THE EXTREME NORTHEAST GREENLAND EVEN MORE.
  • CHARTS OF THE WEST GREENLAND COASTLINES ARE MISPLACED BY 0-1,000 METRES. 

See the following articles in the GeoGarage blog :

These charts are automatically viewable on mobile applications :


Using charts safely involves keeping them up-to-date using Notices to Mariners