[CF-metadata] Sea water pH values: at standard or in-situ conditions?

John Dunne - NOAA Federal john.dunne at noaa.gov
Thu Jun 8 11:58:18 MDT 2017

Hi Matthias,

I'm going to have to go with in-situ, unless someone can correct me
otherwise.  I'm 86.33% confident, however.  I have been looking at Jim
Orr's documentation (
http://www.geosci-model-dev-discuss.net/gmd-2016-155/gmd-2016-155.pdf), and
it cites:

Dickson, A. G., Sabine, C. L., and Christian, J. R.: Guide to best
practices for ocean CO2 measurements, , PICES Special Publication 3, 191
pp., http://aquaticcommons.org/1443/, 2007.
which gives the calculations for pH on the total scale in SOP6a and SOP6b
as a function of insitu T as a variable.  Also, I would argue from an
environmental science perspective that we *should* be posting the insitu

Hope that helps! John

On Thu, Jun 8, 2017 at 5:56 AM, Matthias Tuma <mtuma at wmo.int> wrote:

> Hello all,
> we had a question come up for the "sea_water_ph_reported_on_total_scale"
> standard name: it appears that for some communities, in particular on the
> measurement side, pH would regularly be reported only after first having
> converted to its equivalent at standard conditions (25C, 0dbar). In other
> communities, pH would most regularly be reported at in-situ conditions
> (temperature and pressure at actual measurement spot).
> While we assume that the CF conventions would implicitly assume values to
> be reported at in-situ conditions (i.e., the latter variant), my two
> questions are:
> 1) whether someone can confirm this, to be 100% certain?, and
> 2) whether adding a few according clarifying words to the description
> would be seen as useful?
> Thanks and best,
> Matthias
> --
> Matthias Tuma
> WCRP Junior Professional Officer
> c/o WMO
> 7bis, avenue de la Paix
> Case postale 2300
> CH-1211 Geneva 2
> Switzerland
> Tel: +41 22 730 8217 <+41%2022%20730%2082%2017>
> Fax: +41 22 730 8036 <+41%2022%20730%2080%2036>
> Email: mtuma at wmo.int
> http://www.wcrp-climate.org
> ------------------------------------------------------------
> ------------------
> The information contained in this electronic message and any attachments
> are intended for specific individuals or entities, and may be confidential,
> proprietary or privileged. If you are not the intended recipient, please
> notify the sender immediately, delete this message and do not disclose,
> distribute or copy it to any third party or otherwise use this message. The
> content of this message does not necessarily reflect the official position
> of the World Meteorological Organization (WMO) unless specifically stated.
> Electronic messages are not secure or error free and may contain viruses or
> may be delayed, and the sender is not liable for any of these occurrences.
> ------------------------------------------------------------
> ------------------
>   Please do not print this e-mail unless absolutely necessary - SAVE PAPER
> _______________________________________________
> 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/20170608/cf289e76/attachment-0001.html>

More information about the CF-metadata mailing list