[CF-metadata] "High cloud amount"

From: Jonathan Gregory <j.m.gregory>
Date: Fri, 24 Dec 2004 10:35:37 +0000

Dear Balaji

> What happens when I also want to define "middle" and "low" cloud
> amount? Do I define a single field with 3 Z levels?

Yes, that's the idea. Alternatively, if you want high, medium and low cloud to
be stored in separate data variables, you can have three different size-one
dimensions for them, or you can use scalar coordinate variables.

> Is it possible somehow to associate the words "high", "middle" and
> "low" with the three layers? This is common parlance.

Yes, that could be done, by defining an auxiliary coordinate variable with
the dimension of Z and of character type, containing the descriptive strings.
However, I think we ought to insist that the Z ranges are precisely defined,
and not try to standardise what high, medium and low cloud mean. These are
vague terms, and without precise Z ranges attached to them, I don't think
there is sufficient metadata to allow you to decide whether quantities from
different sources are comparable. What do you think?

Best wishes

Jonathan
Received on Fri Dec 24 2004 - 03:35:37 GMT