[CF-metadata] CF Section 5.3 "Reduced Horizontal Grid" and Section 8.2 "compression by gathering" somewhat inconsistent

From: John Caron <caron>
Date: Sat, 11 Oct 2008 16:18:18 -0600

One thing i forgot to mention, in the 5.3 example:

>
> Example 5.3. Reduced horizontal grid
>
> dimensions:
> londim = 128 ;
> latdim = 64 ;
> rgrid = 6144 ;
> variables:
> float PS(rgrid) ;
> PS:long_name = "surface pressure" ;
> PS:units = "Pa" ;
> PS:coordinates = "lon lat" ;
> float lon(rgrid) ;
> lon:long_name = "longitude" ;
> lon:units = "degrees_east" ;
> float lat(rgrid) ;
> lat:long_name = "latitude" ;
> lat:units = "degrees_north" ;
> int rgrid(rgrid);
> rgrid:compress = "latdim londim";

there seems to be actually no use, or need for, the latdim and londim dimensions or the rgrid variable. what it looks like from the outside is a set of random points, each point has an explicit lat,lon coordinate. Presumably the rgrid "compression index" tells you something about it really being a 2D grid. Exactly what it says about grid connectivity is not immediately obvious.
Received on Sat Oct 11 2008 - 16:18:18 BST