[CF-metadata] CF standard names for chemical constituents and aerosols (resulting from a GRIB2 proposal)

From: Philip J. Cameronsmith1 <cameronsmith1>
Date: Thu, 25 Sep 2008 17:18:14 -0700 (PDT)

On Thu, 25 Sep 2008, Jonathan Gregory wrote:

> Dear Martina, Philip, et al.
>
[....]
>
> "Lumped"/"total": At present, we have only two names with "total":
> mole_fraction_of_total_inorganic_bromine_in_air
> mole_fraction_of_total_reactive_nitrogen_in_air
> I understand "total" here to emphasise that we are considering the total of
> the mole fractions of all the species which "qualify" as inorganic bromine,
> or reactive nitrogen, species. Is that the same as what you mean by "lumped"
> e.g. in "lumped_alkanes"? Why do we need "lumped" or "total"? Would it be
> clear enough just to say mole_fraction_of_alkanes_in_air?

Hi Jonathan, Martina, et al.,

In a previous email I gave my opinion on 'lumped' vs 'total', but missed
Jonathan's suggestion (above) to use neither.

I think it is a reasonable suggestion. I can think of no strong reason why
not. It certainly has the advantage of being shorter.

As a minor issue, there might be a small amount of ambiguity in the mind
of someone reading just the standard name. For example, someone might
think that mole_fraction_of_C4_alkanes_in_air would mean the concentration
of n-butane and isobutane are the same, with the value of one of them
given in the data, whereas CF would mean that the sum of them is in the
data. But I think this is a minor concern, and unlikely to be a problem
in practice.

There is also the advantage with 'total' (or 'lumped') that it does help
indicate to the reader that the standard name is for a lumped specie,
rather than a single unique specie. But again I think this is only a
minor advantage.

If we made this change, would CF be able to alias total_inorganic_bromine
and total_reactive_nitrogen to remove the 'total' for consistency?

In summary, I would be happy to use either 'total' or nothing.

Best wishes,

      Philip


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Dr Philip Cameron-Smith Atmospheric, Earth, and Energy Division
pjc at llnl.gov Lawrence Livermore National Laboratory
+1 925 4236634 7000 East Avenue, Livermore, CA94550, USA
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Received on Thu Sep 25 2008 - 18:18:14 BST