Hi Jon, > I've been following this thread with great interest. For me > it boils down to this question: > > - Is the datum always known by the data provider?
Almost certainly, but by a comparatively small number of individuals within an organisation I would guess. However - and here's the blocker - probably not by many/enough of the people who have the (let's be frank) unglamorous job of compiling metadata for large volumes of spatial data. > > If the answer is "yes" then I see no reason to omit the datum > (and plenty of reasons to include it). If there *are* > situations where the datum is genuinely unknown or undefined > then we need to express this clearly too so users can beware. > > (Previous posts mentioned GCMs as possible situations where > the datum is unknown - is this really true? Surely there is > always a sphere with a known radius on which coordinates are based?) > That would be my assumption also - that the raw facts are always known. In my experience the problem tends to be organisational rather than technical. Few organisations seem to employ staff whose lapel badge reads 'Spatial Metadata Operative'. Which is, I realise, a pretty lame excuse. Anyhows, I'm drifting off topic. Cheers, Phil _______________________________________________ CF-metadata mailing list [email protected] http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
