[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: CLASS and CDM

This archive contains answers to questions sent to Unidata support through mid-2025. Note that the archive is no longer being updated. We provide the archive for reference; many of the answers presented here remain technically correct, even if somewhat outdated. For the most up-to-date information on the use of NSF Unidata software and data services, please consult the Software Documentation first.

  • Subject: Re: CLASS and CDM
  • Date: Wed, 15 Feb 2006 13:29:32 -0700


Ken Knowles wrote:


On Feb 14, 2006, at 11:30 , John Caron wrote:
<snip>
We've been trying to get the CF group to work on datum specification. If we cant get much action from them, we'll have to look for another route. We have also discussed WKT and GML in this regard. Whats your thought about how to specify? 


John,
I meant that in the UML for a CoordinateSystem I don't see any reference to a datum. Don't you need to say what the lat/lon are relative to? Not to mention the elevation. 

 - Ken



Hi Ken:
You're right we do need it. The fact that its not there reflects the historical circumstance that we've been working mostly with global and regional models where the resolutions are so large (eg 50-500 km) that it hasnt mattered. Now as we start working with finer scale data, we obviously do need it. So we need to come up with exactly how to specify this kind of info in the netcdf file or in the thredds catalog. Im hoping NOAA/CF/?? will help us figure it out, and we will extend the data model. Then there will be the problem of getting data providers to include the information.