[CF-metadata] "positive" attribute

From: Bryan Lawrence <b.n.lawrence>
Date: Thu, 28 Jun 2007 08:26:55 +0100

Hi Forrest

Are some of these going to be implicit in the standard name? (I imagine no
always, so I can see the sense of the argument). Personally I don't have a
problem with introducing an extended controlled vocabulary into the positive
argument.

Cheers
Bryan

On Tuesday 26 June 2007 15:03:31 Forrest Hoffman wrote:
> Much of the CF-1.0 convention seems to be atmospherically biased. I
> know that's because it is the atmospheric scientists that pioneered all
> these developments. In attempting to adopt this methodology for other
> components of Earth System Models, I'm concluding it may be necessary to
> extend the convention to adequately support the needs of these components.
>
> For example, it appears to me that the "positive" attribute for CF-1.0
> variables is really used to describe vertical directionality. This
> attribute is often traditionally associated with atmospheric radiation
> variables. In CMOR, the only valid attribute values are "up" and "down."
>
> In terrestrial biogeochemistry various sign conventions exist, and I had
> hoped to use the "positive" attribute to describe the desired convention
> where vertical directionality is not important or known. The values I
> had initially hoped to use for the "positive" attribute for some
> biogeochemistry variables were "into biosphere" and "out of biosphere"
> and "into pool" and "out of pool."
>
> It would seem that "vertical-directionality" would be a more appropriate
> attribute where the "positive" attribute has been traditionally
> applied. I'm sure nobody wants to change this now, but I'm looking for
> suggestions for attributes that might describe sign conventions where
> directionality is either not vertical or is more conceptually abstract.
> We could establish a "negative" attribute, but users might expect some
> kind of correspondence with the "positive" attribute. A
> "sign-convention" attribute might work, but it might have many possible
> values. Any other suggestions?
>
> Forrest
Received on Thu Jun 28 2007 - 01:26:55 BST