[CF-metadata] new TEOS-10 standard names

From: Jonathan Gregory <j.m.gregory>
Date: Tue, 26 Jul 2011 09:49:07 +0100

Dear all

I agree with Roy in his remark that "the existing salinity Standard Name is a
much broader term than the TEOS-10 recommendations".
In some datasets, it may not be well-defined precisely which "kind" of salinity
we have. This is particularly the case for model datasets, since most ocean
models used for climate are not capable of distinguishing owing to the
approximations they make. (I note that CF and the standard name table began
as a convention for GCMs, and later expanded to accommodate observations.) We
cannot redefine the existing standard name because of the existing datasets and
because it is useful to have a "generic" name anyway.

However it is fine both to keep this existing generic name and to define some
new ones to make the distinction in new obs and model datasets where it is
appropriate, as proposed by Paul and Trevor. It is usual in CF to have a choice
of precision for different applications.

On Paul's proposals, I have a couple of comments:

sea_water_preformed_salinity
Definition: Preformed Salinity is a salinity variable that is designed to be as
conservative as possible, by removing the estimated biogeochemical influences
on the seawater composition from other forms of salinity.

I assume this is a newly introduced term. I would say that it would be good
to be more informative. "Preformed" does not tell me what it is - it doesn't
suggest anything in particular to me as a non-expert. CF standard names do not
have to be the term in common use if we could be more self-explanatory.
Perhaps we could be more self-explanatory in this term with a phrase such as
assuming_no_biogeochemical_influence. But actually, I am unsure what that
means - could you explain a bit further? How can salinity not be influenced
by geochemistry, in particular? Please excuse my ignorance.

sea_water_potential_enthalpy
Since this quantity is in J kg-1, I suggest that it should contain the word
"specific". Omitting this might imply that it was an extensive quantity e.g.
an ocean integral. By analogy with the existing standard name
  specific_kinetic_energy_of_sea_water
it might be best phrased as
  specific_potential_enthalpy_of_sea_water
The salinity quantities are by definition intensive and so "specific" is
not required.

Best wishes

Jonathan
Received on Tue Jul 26 2011 - 02:49:07 BST