[CF-metadata] curvilinear cartesian coordinates case

From: Jonathan Gregory <j.m.gregory>
Date: Fri, 24 Nov 2006 17:28:33 +0000

Dear Bert

> * I would prefer if lat and lon are not necessary for some CF-minor
> compliance.
As you and John have recognised, this makes the file less useful to anyone
else. There's nothing to stop you writing non-compliant files for your own
use or use within a project, obviously.

> * I would prefer an extension of the "grid mappings and projections" with
> the attribute "mapped_coordinates" for models using curvilinear cartesian
> coordinates.
I think it is fine to have auxiliary coordinates of x y lat lon all at the
same time, as in your example. You say that
"What is lacking in this example is some clue that x and y are the
coordinates in the Lambert projection."
but that should be clear from their standard names of projection_x_coordinate
and projection_y_coordinate, shouldn't it?

> * I would like to learn that missing_values are allowed for auxiliary
> coordinates.
That is an interesting question and I think you are right that we have not
discussed it in the standard. I think we should allow it. Missing data is
not allowed for 1D coord variables as they have to be usable for subsetting
and ordering the axis.

Cheers

Jonathan
Received on Fri Nov 24 2006 - 10:28:33 GMT