Hi Philip and Jonathan,
Just to add my opinion to this before the debate withers. It does
seem odd to put "anomaly" in the standard name, particularly since
there are many types of anomaly (from any number of well-known
climatologies or less well-known ad hoc mean fields). It doesn't seem
like a good idea to keep pushing new things into the standard name
(which already seem rather overloaded IMHO).
I don't have time right now to think of a better alternative but I
would have thought that a separate attribute or modifier would be more
sensible, avoiding a potentially-huge many-to-many relationship that
could blow up the standard name table.
Also, what if someone wants to express a new anomaly that isn't in the
standard name table? If the anomaly is expressed in the standard name
then they have to go through a procedure to standardize the name
before they can use it "legally". I bet a lot of people won't bother
to do this. If there were a more generic way of expressing anomalies
then they could use this immediately.
> From Jonathan:
> As you say, very few have so far been needed.
In general, I would be very careful of interpreting community silence
to mean that there is no community need. This mailing list is
composed of a statistically-small number of very busy people. I
shouldn't even be replying to this myself, I have lots of deadlines
this week... ;-)
Jon
On Thu, Apr 3, 2008 at 3:06 PM, Philip Bentley
<philip.bentley at metoffice.gov.uk> wrote:
>
> Hi Jonathan,
>
> Interesting to learn that this idea was raised previously. If it again
> fails to receive any supporting voices then I guess it's a non-starter. No
> problem: we'll go down the normal standard names route.
>
> Regards,
>
> Phil
>
>
> Dear Phil
>
> > Yet is it not the case that the physical property described by the
> > 'canonical' name and its associated 'anomaly' name is fundamentally
> > the same? All that's changed is the use of a different reference datum
> > (i.e. climatological mean instead of zero).
> > So rather than create "_anomaly" variants of potentially hundreds of
> > CF standard names, would an alternative solution be to add the term
> > "anomaly" to the list of standard name modifiers (cf. Appendix C in CF
> > spec)? In which case we'd be able to use names such as:
> > "air_temperature anomaly"
> > "lwe_precipitation_rate anomaly"
> > "air_pressure_at_sea_level anomaly"
> > and so on
>
> Following an email thread started by Julian Hill, he and I also thought we
> would propose exactly this, and I mentioned the proposal at the GO-ESSP
> meeting
> in Paris last June. However it wasn't received enthusiastically. It is a bit
> different in concept from the other standard_name modifiers, which are
> generally intended for "fields of metadata" - standard errors and so on.
> The anomaly of a quantity is arguably more of a different quantity
> altogether;
> a time-interval, for instance, is a different thing from an absolute time.
>
>
>
> I agree that in principle any quantity *could* be an anomaly, but in
> practice
> are we *actually* going to need anomaly quantities for all of them (or a
> fraction of them which is nearer 100% than 10%, say)? As you say, very few
> have
> so far been needed. Perhaps we should decide on that kind of basis how to
> deal
> with it.
>
> Other views would be helpful.
>
> Best wishes
>
> Jonathan
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>
>
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>
>
--
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Dr Jon Blower Tel: +44 118 378 5213 (direct line)
Technical Director Tel: +44 118 378 8741 (ESSC)
Reading e-Science Centre Fax: +44 118 378 6413
ESSC Email: jdb at mail.nerc-essc.ac.uk
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Received on Thu Apr 03 2008 - 08:39:53 BST
