[CF-metadata] CF Conventions 1.2

From: Jonathan Gregory <j.m.gregory>
Date: Thu, 8 May 2008 12:04:14 +0100

Dear Phil

> Perhaps the recent
> flurry of CF proposal activity in part reflects a general desire to
> 'play catch-up'.

Yes, I think that is the case. It certainly is the case for the two proposals
I have made, on the axis and cell_methods attributes. These were discussed on
the email list and in abeyance for a long time because we had no way to adopt
them formally until we agreed the new rules.

> I can produce some simple test files for the changes at CF 1.2. But
> the question of what constitutes application conformance is, I
> suggest, not easily defined. For instance, I could create a noddy
> netcdf file with two new grid mapping attributes, as follows:

Yes, I think such a file would be useful, because it does at least provide
input data that the cf-checker can check for conformance, and other
applications could likewise check that they can read in and interpret, if they
are interested in these features. I agree with you that what "compliance"
actually means for an application is ill-defined. This is an issue which has
come up before, of course. Since most of CF is optional, in one sense (but not
a very useful sense) an application is compliant even if it ignores all that
optional metadata. On the other hand I am sure no application currently exists
which interprets all the metadata. But I don't think that means the metadata is
not useful. It can still be read by humans, it describes the data properly,
and we only add features when people have a need for them (usually people who
intend to produce data).

Best wishes

Jonathan
Received on Thu May 08 2008 - 05:04:14 BST