They are arranged into UTM zone folders, each covering 6x4 degrees. Each folder contains up to 24 1x1 degree files, in SRTM HGT format (3" resolution, 1201 rows x 1201 columns).
These DEMs were created from 250K and 500K topographic maps and Landsat imagery (coastal areas), and reprojected ICESat data (interior, see NSIDC page). There is some input from a 100K map of the Gunnbjorn are, and from SRTM data south of 60°21' of latitude.
Although, for consistency with other DEM data on the Viewfinder Panoramas site, they have a resolution of 3", their true resolution in most areas is lower. The source contour spacing is generally 100 metres, so detail in areas of low relief is poor. Accuracy in mountain areas should be generally fair, and considerable improvement on anything else currently on the web, although there may be some local horizontal displacements, especially in the west. There here may be substatial error margins on the coastal icefields; in particular, only very limited topographic information could be found about the heights of some of the ice domes.
There are still a few known oustanding issues, including some local terracing on UTM zone boundaries. These will be addressed soon.
My thanks again to Christoph Hormann of Freiburg, Germany for processing this awkward dataset into DEM data.
Jonathan de Ferranti
26 March 2021 Greenland Second Edition, downloadable from the 1" coverage map.. Primary source is ArcticDEM from the Polar Geospatial Centre but in high relief areas there is considerable input from ALOS, and to a lesser extent, ASTER and TANDEM. The resolution, accuracy and level of detail are all very much greater than that of the first edition.
9 April 2009
Greenland First Edition. The whole of Greenland is available via the 3" coverage map.
The 3" Greenland DEM is divided into four sections:
Fife, Scotland