[CF-metadata] WRF staggered grids

[John Caron]

Has there been any discusion of staggered coordinate systems? Im looking 
at the WRF model output to recomend how to convert it to using CF. It 
has variables on various staggerings, for example U is on (z,y,x_stag) 
while V is on (z, y_stag, x), and W is on (z_stag,y,x), where the 
staggered coordinates are the  "edges" of the non-staggered coordinates.

On first pass these could constitute seperate coordinate systems, but it 
seems like it would be better to represent how they are related.

Also, WRF outputs two fields whoch if you add together, gives you the 
pressure field on the non-staggered grid. To get a pressure coordinate 
on the staggered grids, one has to interpolate. One could express all 
that as a formula, as we do other vertical coordinate systems, but it 
seems a little clumsy.

Any thoughts in general, or specifics from anyone familiar with the WRF 
model?