Three of the DMI files were used for each image:
xxxxxx.area.shp grid locations of the
shape
xxxxxx.area.shx index to the shapes
in the xxx.shp file
xxxxxx.area.dbx attribute information
for each shape
Compared to the sample NIC shape files, the DMI files are somewhat easier
to work with.
The principle difference is that the DMI shapes use a lat/lon coordinate
system, as opposed to the use of a gridded system of x/y locations.
To convert to the EASE format, the NIC shape files require converting to
lat/lon and then converting to the new projection. Since each center
may use different map projections, spheroids, false eastings/northings,
etc., it is a great help if the locations are in lat/lons.
Several examples are provided here showing different resolutions with side-by-side comparisons of ice concentrations derived from SSM/I.
There is a slight difference between the map and shapes. Different map databases are not the same, but the registration is fairly good.
At the full resolution of SSM/I at 25 km:
At about 12.5 km resolution showing the full DMI grid:
At a resolution of about 6 km:
And finally at a resolution of about 1 km:
An animation of all the images for year 2000 is also provided. The spacing between files is about 1 week. The animation may take a while to load (about 1.8 megs).
