Dear CF community,
After consulting my colleagues at NODC (Hernan and Tim), we have agreed on
the following definition as suggested by John Graybeal:
Apparent Oxygen Utilization (AOU) is the difference between measured
dissolved oxygen concentration in water, and the equilibrium saturation
concentration of dissolved oxygen in water with the same physical and
chemical properties.
Reference: Broecker, W. S. and T. H. Peng (1982), Tracers in the Sea,
Lamont-Doherty Earth Observatory, Palisades, N. Y.
Thanks for being patient with us on this.
Regards,
Ajay
On Tue, Mar 3, 2015 at 2:01 PM, John Graybeal <jbgraybeal at mindspring.com>
wrote:
> As I Am Not A Scientist, may I suggest that the text that was lost in this
> latest round, "It is used to estimate the change in dissolved oxygen in a
> parcel of water due to biological and chemical processes at depth since it
> left the surface." is important, because it explains to the rest of us why
> the term is called Apparent Oxygen Utilization. Though this phrasing may
> be better:
>
> > It is used as an estimate of the change in dissolved oxygen in a parcel
> of water since leaving the surface, due to biological and chemical
> processes at depth.
>
> If Roy's phrasing is agreeable to Hernan, I suggest making the two phrases
> of his definition roughly parallel:
>
> > "Apparent Oxygen Utilization (AOU) is the difference between measured
> dissolved oxygen concentration in water, and the equilibrium saturation
> concentration of dissolved oxygen in water with the same physical and
> chemical properties."
>
> Makes it easier to compare them.
>
> John
>
>
> On Mar 3, 2015, at 09:03, Lowry, Roy K. <rkl at bodc.ac.uk> wrote:
>
> > Hi again Hernan,
> >
> > I was taking T and S as being constant, not trying to be prescriptive
> about computation algorithm. Next proposal (based on a Wikipedia quote
> from Garcia et al 2006):
> > Apparent Oxygen Utilization (AOU) is the difference between the measured
> dissolved oxygen concentration and its equilibrium saturation concentration
> in water with the same physical and chemical properties. Reference:
> Broecker, W. S. and T. H. Peng (1982), Tracers in the Sea, Lamont-Doherty
> Earth Observatory, Palisades, N. Y.
> > Are you happier with that?
> >
> > Cheers, Roy.
> >
> > From: Hernan Garcia - NOAA Federal [mailto:hernan.garcia at noaa.gov]
> > Sent: 03 March 2015 16:37
> > To: Lowry, Roy K.
> > Cc: Ajay Krishnan - NOAA Affiliate; alison.pamment at stfc.ac.uk;
> cf-metadata at cgd.ucar.edu; Tim Boyer - NOAA Federal
> > Subject: Re: [CF-metadata] Request for new standard-name:
> apparent_oxygen_utilization
> >
> > Rigourously speaking, the O2 solubility in water involves an atmospheric
> pressure term, a temperature, and salinity terms which are all variables
> (See for example; Benson and Krause, 1984; Garcia and Gordon, 1992). I
> would leave AOU at at the definition level and not how it should be
> computed. This definition of AOU is a LOT more complicated than most folks
> realize; my 2 cents. I will leave it to you all to decide.
> >
> > On Tue, Mar 3, 2015 at 11:27 AM, Lowry, Roy K. <rkl at bodc.ac.uk> wrote:
> > Hi Hernan,
> >
> > Shouldn't you specifically mention that it's the oxygen solubility at
> atmospheric pressure? I would also still like to keep the reference.
> >
> > That would take us to:
> >
> > Apparent Oxygen Utilization (AOU) is the difference between the oxygen
> solubility at a pressure of 1 atmosphere (101325 Pa) and the measured
> dissolved oxygen concentration in water. Reference: Broecker, W. S. and T.
> H. Peng (1982), Tracers in the Sea, Lamont-Doherty Earth Observatory,
> Palisades, N. Y.
> >
> > Is that acceptable?
> >
> > Cheers, Roy.
> >
> > From: Hernan Garcia - NOAA Federal [mailto:hernan.garcia at noaa.gov]
> > Sent: 03 March 2015 16:11
> > To: Lowry, Roy K.
> > Cc: Ajay Krishnan - NOAA Affiliate; alison.pamment at stfc.ac.uk;
> cf-metadata at cgd.ucar.edu; Tim Boyer - NOAA Federal
> > Subject: Re: [CF-metadata] Request for new standard-name:
> apparent_oxygen_utilization
> >
> > Hello,
> >
> > Let me make the following suggestion for consideration. For simplicity,
> I suggest adopting the following definition:
> >
> > Apparent Oxygen Utilization (AOU): The difference between the dissolved
> oxygen solubility and the measured dissolved oxygen concentration in water.
> >
> > Thanks,
> >
> > Hernan
> >
> >
> >
> >
> >
> >
> > On Fri, Feb 27, 2015 at 11:46 AM, Lowry, Roy K. <rkl at bodc.ac.uk> wrote:
> > Hi Ajay,
> >
> > To me, this doesn't differ significantly from Alison's words except it
> uses 'parcel of water' rather than 'sea water' and 'in equilibrium with the
> atmosphere' rather than 'saturation at a pressure of one atmosphere'. My
> only problem is that CF definitions don't usually include units. Like Nan,
> I also like the inclusion of the reference in Alison's definition.
> >
> > Would everybody be happy with:
> >
> > Apparent Oxygen Utilization (AOU) is defined as the difference between
> the solubility concentration of oxygen in equilibrium with the atmosphere
> at the temperature and salinity of a parcel of water and the observed
> dissolved oxygen concentration. It is used to estimate the change in
> dissolved oxygen in a parcel of water due to biological and chemical
> processes at depth since it left the surface. Reference: Broecker, W. S.
> and T. H. Peng (1982), Tracers in the Sea, Lamont-Doherty Earth
> Observatory, Palisades, N. Y.? I have deliberately included ?in sea water?
> in the first sentence of the definition to make it clear that this is an
> oceanographic quantity.
> >
> > We need to agree something. At the moment we seem to be doing everything
> possible to prevent this Standard Name being accepted!!!
> >
> > Cheers, Roy.
> > ________________________________________
> > From: Ajay Krishnan - NOAA Affiliate [ajay.krishnan at noaa.gov]
> > Sent: 27 February 2015 16:32
> > To: Lowry, Roy K.; Hernan Garcia - NOAA Federal
> > Cc: alison.pamment at stfc.ac.uk; cf-metadata at cgd.ucar.edu
> > Subject: Re: [CF-metadata] Request for new standard-name:
> apparent_oxygen_utilization
> >
> > Hi Alison,
> >
> > I had to defer this to to our subject matter expert, Hernan Garcia. His
> response is copied below. I am also including Hernan in this email now,
> just so that we're all on the same page, moving forward.
> >
> > Apparent Oxygen Utilization (AOU) is defined as the difference between
> the solubility concentration of oxygen in equilibrium with the atmosphere
> at the temperature and salinity of a parcel of water and the observed
> dissolved oxygen concentration. It is used to estimate the change in
> dissolved oxygen in a parcel of water due to biological and chemical
> processes at depth since it left the surface. AOU and dissolved oxygen
> concentrations are nominally expressed in micro-moles per kilogram (umol
> kg^-1)
> >
> >
> > Thanks,
> > Ajay
> >
> >
> >
> >
> > On Fri, Feb 27, 2015 at 3:47 AM, Lowry, Roy K. <rkl at bodc.ac.uk<mailto:
> rkl at bodc.ac.uk>> wrote:
> > Hello Alison,
> >
> > Looks good to me.
> >
> > Cheers, Roy.
> > ________________________________________
> > From: alison.pamment at stfc.ac.uk<mailto:alison.pamment at stfc.ac.uk> [
> alison.pamment at stfc.ac.uk<mailto:alison.pamment at stfc.ac.uk>]
> > Sent: 26 February 2015 18:11
> > To: Lowry, Roy K.; ajay.krishnan at noaa.gov<mailto:ajay.krishnan at noaa.gov>;
> cf-metadata at cgd.ucar.edu<mailto:cf-metadata at cgd.ucar.edu>
> > Subject: RE: [CF-metadata] Request for new standard-name:
> apparent_oxygen_utilization
> >
> > Dear Ajay, Roy, All,
> >
> > Thank you for the clarification regarding units.
> >
> > We are now settled on
> > apparent_oxygen_utilization (mol kg-1).
> >
> > We do already have a couple of ocean biogeochemistry names referring to
> ?nitrate utilization? so I think this new name is in keeping with those.
> >
> > Based on the definition provided by Ajay and John Graybeal?s suggested
> wording, I have currently written the definition as:
> > ?Apparent Oxygen Utilization (often abbreviated as AOU) is the
> difference between the saturation concentration of oxygen in sea water at a
> pressure of 1 atmosphere (101325 Pa) and the observed oxygen concentration.
> It is used to estimate the change in oxygen concentration due to biological
> and chemical processes. Reference: Broecker, W. S. and T. H. Peng (1982),
> Tracers in the Sea, Lamont-Doherty Earth Observatory, Palisades, N. Y.? I
> have deliberately included ?in sea water? in the first sentence of the
> definition to make it clear that this is an oceanographic quantity.
> >
> > Does this all look OK? If so, then I think the name can be accepted for
> inclusion in the standard name table.
> >
> > Best wishes,
> > Alison
> >
> > ------
> > Alison Pamment Tel: +44 1235 778065
> <tel:%2B44%201235%20778065>
> > NCAS/Centre for Environmental Data Archival Email:
> alison.pamment at stfc.ac.uk<mailto:alison.pamment at stfc.ac.uk><mailto:
> J.A.Pamment at rl.ac.uk<mailto:J.A.Pamment at rl.ac.uk>>
> > STFC Rutherford Appleton Laboratory
> > R25, 2.22
> > Harwell Oxford, Didcot, OX11 0QX, U.K.
> >
> >
> > From: CF-metadata [mailto:cf-metadata-bounces at cgd.ucar.edu<mailto:
> cf-metadata-bounces at cgd.ucar.edu>] On Behalf Of Lowry, Roy K.
> > Sent: 26 February 2015 15:29
> > To: Ajay Krishnan - NOAA Affiliate; cf-metadata at cgd.ucar.edu<mailto:
> cf-metadata at cgd.ucar.edu>
> > Subject: Re: [CF-metadata] Request for new standard-name:
> apparent_oxygen_utilization
> >
> > Hi Alison,
> >
> > Just to clarify that I am in total agreement with this and had a bit of
> a senior moment in a previous message.
> >
> > Cheers, Roy.
> >
> > ________________________________
> > From: Ajay Krishnan - NOAA Affiliate [ajay.krishnan at noaa.gov<mailto:
> ajay.krishnan at noaa.gov>]
> > Sent: 26 February 2015 14:56
> > To: cf-metadata at cgd.ucar.edu<mailto:cf-metadata at cgd.ucar.edu><mailto:
> cf-metadata at cgd.ucar.edu<mailto:cf-metadata at cgd.ucar.edu>>
> > Subject: Re: [CF-metadata] Request for new standard-name:
> apparent_oxygen_utilization
> >
> > Hi Alison,
> >
> > Yes, please use mol kg-1 as the canonical unit.
> >
> > Thanks,
> >
> > Ajay
> >
> > alison.pamment at stfc.ac.uk<http://stfc.ac.uk><http://stfc.ac.uk>
> alison.pamment at stfc.ac.uk<http://stfc.ac.uk> <mailto:
> cf-metadata%40cgd.ucar.edu<mailto:cf-metadata%2540cgd.ucar.edu
> >?Subject=Re%3A%20%5BCF-metadata%5D%20Request%20for%20new%0A%09standard-name%3A%09apparent_oxygen_utilization&In-Reply-To=%3C014539AC4976BE4490A360410A8C20178A2D6062%
> 40EXCHMBX01.fed.cclrc.ac.uk<http://40EXCHMBX01.fed.cclrc.ac.uk>%3E>
> > Thu Feb 26 03:56:32 MST 2015
> >
> > Dear All,
> >
> >
> >
> > Thank you for the constructive discussion of this proposal - it seems
> that agreement has been reached on apparent_oxygen_utilisation with
> canonical units of mol kg-1. (Just to double check: is this the correct
> unit for use with the World Ocean Database, which I believe is the reason
> for requesting the name in the first place. Units of mol m-3 have also been
> mentioned in this discussion, but this could be a misunderstanding.
> >
> >
> >
> > Best wishes,
> >
> > Alison
> >
> >
> >
> >
> >
> > ________________________________
> > 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.
> >
> > 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.
> >
> > 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.
> >
> >
> >
> > --
> > Hernan E. Garcia, Ph.D.
> > NOAA NESDIS Program Coordination Officer
> > Office of the Under Secretary
> > 1401 Constitution Avenue NW, Room 61021
> > Washington, DC 20230
> > Desk: (202) 482-1567
> > Cell: (301) 938-5895
> > E-mail: Hernan.Garcia at noaa.gov
> >
> > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > The contents of this message are mine
> > personally and do not reflect any position
> > of the U.S. Government or NOAA
> > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> >
> > 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.
> >
> >
> >
> > --
> > Hernan E. Garcia, Ph.D.
> > NOAA NESDIS Program Coordination Officer
> > Office of the Under Secretary
> > 1401 Constitution Avenue NW, Room 61021
> > Washington, DC 20230
> > Desk: (202) 482-1567
> > Cell: (301) 938-5895
> > E-mail: Hernan.Garcia at noaa.gov
> >
> > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > The contents of this message are mine
> > personally and do not reflect any position
> > of the U.S. Government or NOAA
> > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> >
> > 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.
> > _______________________________________________
> > 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/20150309/1417ee6c/attachment-0001.html>
Received on Mon Mar 09 2015 - 13:43:52 GMT
