Dear Etienne Thanks for your helpful email, and sorry for slow response.
> Ok you mean that we could add new projections easily to the CF > standard? That's great to know. Yes, you could do this with a trac ticket, like ticket 72, which proposes to add the geos projection. See https://cf-pcmdi.llnl.gov/trac/query > I'm not sure I understand your question - do you mean to ask if these > additions to CF would be sufficient to describe most WKT definitions > in pure CF metadata (without the WKT)? Yes, that's what I mean. I'm interested to know how many other elements of WKT are used in the cases you deal with. > It seems that > for many applications (especially at the scale most netcdf files are > used for), TOWGS84 parameters are sufficient. A named datum would be > nice, but there are quite a few different ways to identify datums (OGC > vs ESRI). OK. If they are standardised lists, we could provide attributes to store them in. > Here is a small compilation of the compatabilities between WKT (as > GDAL sees it) and CF-1.5 projections, there are a few > problems/unknowns with some projections: > http://trac.osgeo.org/gdal/wiki/NetCDF_ProjectionTestingStatus If you identify errors or inadequacies with CF definitions from your detailed analysis, you could propose they be corrected, again with a CF trac ticket, in this case as a "defect" rather than an addition to the standard. > The following page lists WKT parameters: > http://www.geoapi.org/2.0/javadoc/org/opengis/referencing/doc-files/WKT.html Yes, this is a useful page. > There are a few other parameters like VERT_CS, COMPD_CS and VERT_DATUM > that some users may need. The VERT_CS and VERT_DATUM appear to be names (in the Newlyn example). Are these names standardised? Best wishes and thanks for your help Jonathan _______________________________________________ CF-metadata mailing list CF-metadata@cgd.ucar.edu http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata