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[netCDF #GGI-666903]: question about standard grids in CF convention

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  • Subject: [netCDF #GGI-666903]: question about standard grids in CF convention
  • Date: Tue, 05 Apr 2011 09:35:53 -0600
Hi John,

> We've been developing a netCDF3 product and trying to comply with CF
> conventions. We want the product on one of the standard grids, e.g.,
> global equal area cylindrical. We would like to use a netCDF3 standard
> grid so that we don't need to include the latitude/longitude pair for each
> gridpoint - but were told that the CF convention requires a lat-lon value
> for each gridpoint regardless of the grid projection selected/used - i.e.,
> that the grid and projection parameterization in the CF convention is not
> complete enough for clients (e.g., IDV) to compute a gridpoint lat-lon.
> 
> Just want to confirm - doesn't seem to make sense to me - why have
> standard grids if you need to include lat-lon values for every gridpoint?
> 
> I'd welcome any clarification you can offer.

There's a discussion of exactly this issue on the CF conventions
mailing list that clarifies why lat/lon pairs are still required for
CF compliance.  The mailng list thread of 12 postings starts here:

  http://mailman.cgd.ucar.edu/pipermail/cf-metadata/2009/006550.html

Steve Hankin's response is especially comprehensive and persuasive.
For more discussion of the issue, you can see the CF Trac tickets #9
and #18

I hope that helps.

--Russ

Russ Rew                                         UCAR Unidata Program
address@hidden                      http://www.unidata.ucar.edu



Ticket Details
===================
Ticket ID: GGI-666903
Department: Support netCDF
Priority: Normal
Status: Closed