[gdal-dev] NetCDF grid mapping read issue

[Andreas Oxenstierna]

Dear list,

GRID cannot interpret (tested with 1.9 and 1.10) the coordinate systems 
in two different NetCDF files storing oceanographic/meteorological data.
But it can interpret the coordinates in a third NetCDF file.
PANOPLY, as available from http://www.giss.nasa.gov/tools/panoply/, can 
correctly display all files in lat-lon (4326).

NetCDF file where GDAL can interpret the coordinates:
https://dl.dropboxusercontent.com/u/13880880/metoffice_foam1_orca025_GLO_ASLV_b20120923_dm20120921.nc 
   (CF convention is 1.0)

NetCDF files where GDAL cannot interpret the coordinates:
https://dl.dropboxusercontent.com/u/13880880/metoffice_foam1_orca025_NTV_ASLV_b20110921_dm20110921.nc 
   (CF convention is 1.0)
http://thredds.met.no/thredds/fileServer/metno/proff4km/default/files/proffDefault4km_2013-04-25_00.nc 
(be warned: 1.2 Gb)    (CF convention is 1.4)

We have got this information from the Norwegian experts:
For PROFF data, the rotated lat/lon coordinates are defined so that each 
latitude and each longitude (and therefore each data point) correspond 
to elements in the rlat/rlon vectors.

The GeoTransform array mentioned in http://www.gdal.org/frmt_netcdf.html 
seems not to be used for these two files.

-- 
Best Regards

Andreas Oxenstierna
T-Kartan Produkt AB
mobile: +46 733 206831
mailto: ao at t-kartor.se
http://www.t-kartor.com