[CF-metadata] Silicate vs. dissolved inorganic silicon

John Dunne - NOAA Federal john.dunne at noaa.gov
Fri Mar 24 11:14:07 MDT 2017


Is the plan also to demote the "silicate" and "phosphate" names?  That
would seem to make sense to me, consistent with Jim's points.

On Fri, Mar 24, 2017 at 12:13 PM, <martin.juckes at stfc.ac.uk> wrote:

> Dear Jim,
>
> thanks. I think that means that we need a corrections to the statements,
> from the CF Standard Name list, that:
>
> (1) '"Dissolved inorganic phosphorus" means phosphate ions in solution' in
> the CF Standard Name definition for mole_concentration_of_
> dissolved_inorganic_phosphorus_in_sea_water, and
> (2) '"Dissolved inorganic silicon" means silicate ions in solution' in the
> definition of mole_concentration_of_dissolved_inorganic_silicon_
> in_sea_water
>
> regards,
> Martin
> ________________________________________
> From: James Orr [James.Orr at lsce.ipsl.fr]
> Sent: 24 March 2017 15:46
> To: Lowry, Roy K.
> Cc: Juckes, Martin (STFC,RAL,RALSP); cf-metadata at cgd.ucar.edu
> Subject: Re: [CF-metadata] Silicate vs. dissolved inorganic silicon
>
> Dissolved inorganic phosphorus in seawater takes several forms, with
> phosphate (P043-) being only one of them. Furthermore, PO43- is not
> even the most abundant form at normal seawater pH. Rather it is HPO42-
> (hydrogen phosphate). Oceanographers do often refer to phosphate but
> what they really taking about is total dissolved inorganic phosphorus
> (the sum of all inorganic forms).
>
> The seawater system for dissolved inorganic silicon is simpler because
> we only need to consider two forms: silicic acid (Si(OH)4) and silicate
> (SiO(OH)3-). The former is more abundant than the latter in seawater.
>
> It is best then to refer to
> - total dissolved inorganic phosphorus rather than phosphate and
> - total dissolved inorganic silicon rather than silicate.
>
> For more insight see the last figure in the OMIP-BGC protocols paper
> in the CMIP6 special issue at
>
> http://www.geosci-model-dev-discuss.net/gmd-2016-155/
>
> Cheers,
>
> Jim
>
> On Fri, 24 Mar 2017, Lowry, Roy K. wrote:
>
> > Dear All,
> >
> >
> > If one makes the assumption that all the silicon and phosphorus atoms
> not associated with organic ligands are
> > in a single chemical form associated with oxygen in solution then what
> Martin says is correct. In my
> > experience I have never known anybody challenge this assumption and I
> cannot think of any other anions
> > incorporating P and Si. Consequently, I would agree that whilst there is
> a theoretical semantic difference
> > between the members of each Standard Name pair I would agree that this
> could be ignored and they could be
> > considered synonyms.
> >
> >
> > Note, this only holds true as these are MOLE concentrations. The MASS
> concentration of inorganic phosphorus
> > is very different from the MASS concentration of phosphate as the oxygen
> atoms have mass.
> >
> >
> > If the decision is taken to take action on this then I would recommend
> that the 'inorganic_silicon' and
> > 'inorganic_phosphorus' names be than ones to be converted to aliases.
> This is based on common terminology
> > usage in the oceanographic community.
> >
> >
> > Cheers, Roy.
> >
> >
> > Please note that I partially retired on 01/11/2015. I am now only
> working 7.5 hours a week and can only
> > guarantee e-mail response on Wednesdays, my day in the office. All
> vocabulary queries should be sent to
> > enquiries at bodc.ac.uk. Please also use this e-mail if your requirement
> is urgent.
> >
> >
> >
> > ____________________________________________________________
> _________________________________________________
> > From: CF-metadata <cf-metadata-bounces at cgd.ucar.edu> on behalf of
> martin.juckes at stfc.ac.uk
> > <martin.juckes at stfc.ac.uk>
> > Sent: 24 March 2017 08:48
> > To: cf-metadata at cgd.ucar.edu
> > Subject: [CF-metadata] Silicate vs. dissolved inorganic silicon
> > Hello Alison, others,
> >
> > the standard name list includes both
> > (1) mole_concentration_of_dissolved_inorganic_silicon_in_sea_water and
> (2)
> > mole_concentration_of_silicate_in_sea_water
> >
> > The definition of the first says that "dissolved inorganic silicon"
> means silicate ions in solution. Both
> > have units of "mol m-3". It looks to me as though they are describing
> the same thing. If this is true, should
> > one be demoted to the alias of the other? If they are different, what is
> the difference?
> >
> > The same question applies to mole_concentration_of_dissolved_inorganic_phosphorus_in_sea_water
> and
> > mole_concentration_of_phosphate_in_sea_water.
> >
> > regards,
> > Martin
> >
> > _______________________________________________
> > CF-metadata mailing list
> > CF-metadata at cgd.ucar.edu
> > http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
> > CF-metadata Info Page - mailman.cgd.ucar.edu Mailing Lists
> > mailman.cgd.ucar.edu
> > This is an unmoderated list for discussions about interpretation,
> clarification, and proposals for extensions
> > or change to the CF conventions.
> >
> >
> > ____________________________________________________________
> _________________________________________________
> > This message (and any attachments) is for the recipient only. NERC is
> subject to the Freedom of Information
> > Act 2000 and the contents of this email and any reply you make may be
> disclosed by NERC unless it is exempt
> > from release under the Act. Any material supplied to NERC may be stored
> in an electronic records management
> > system.
> >
> > ____________________________________________________________
> _________________________________________________
> >
> >
>
> --
> LSCE/IPSL, Laboratoire des Sciences du Climat et de l'Environnement
> CEA-CNRS-UVSQ
>
> LSCE/IPSL, CEA Saclay http://www.ipsl.jussieu.fr/~jomce
> Bat. 712 - Orme mailto: James.Orr at lsce.ipsl.fr
> Point courrier 132
> F-91191 Gif-sur-Yvette Cedex Phone: (33) (0)1 69 08 39 73
> FRANCE Fax: (33) (0)1 69 08 30 73
> _______________________________________________
> CF-metadata mailing list
> CF-metadata at cgd.ucar.edu
> http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.cgd.ucar.edu/pipermail/cf-metadata/attachments/20170324/3810c677/attachment-0001.html>


More information about the CF-metadata mailing list