Hi, ----- Original Message ----- From: "Bentley, Philip" <[email protected]> Date: Wednesday, August 3, 2011 11:17 am Subject: Re: [CF-metadata] the need to store lat/lon coordinates in a CF-compliant netCDF file
> 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? Tthe World Ocean Database ( http://www.nodc.noaa.gov/OC5/WOD09/pr_wod09.html ), which is creating by aggregating and standardizing datasets collected over a long period of time, has some datasets which go all the way back to the time of James Cook. Some of these datasets, I am certain, have datum which is not known. But, I think the provider could still give a best guess for what the datum could have been with adequate qualification instead of leaving it to the user to select arbitrary datum. Upendra > > 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 > _______________________________________________ CF-metadata mailing list [email protected] http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
