At 2:42 PM -0600 9/23/07, Don Murray wrote:
What is the compelling reason to have to have a Z coordinate?
That's not required for 2D grids in CF (e.g. total_precipitation)
so I'm not sure why it would be required for point data either.
The relevant point for me is that the actual z location of a measurement
*can* make a difference in the interpretation of data, but the providers
often don't consider it important to provide (even though often it could
be trivial to provide). Classic case being the height of the wind
sensor.... So I'm not sure you would consider this compelling, but as
a *user* of data observations, having the provider explicitly provide
whatever z knowledge they have -- whether it's to say 'surface',
or 'unknown', or 'surface + 3m +/- 1.5m' -- is very powerful. It would
increase my confidence in being able to use the data set, because I'd
know that the provider at least thought about it.
One likes to assume the providers wouldn't lie just to get the field
filled in, of course.... Maybe we need a 'decline to state' string. :->
John Graybeal <mailto:graybeal@xxxxxxxxx> -- 831-775-1956
Monterey Bay Aquarium Research Institute
Marine Metadata Initiative: http://marinemetadata.org ||
Shore Side Data System: http://www.mbari.org/ssds