Dear All, Many thanks for the discussion of this name. I think agreement has been reached on the definition and no further changes have been suggested, so I will accept this name and include it in the standard name table update which is scheduled for today. Full details of today's update will follow shortly.
Best wishes, Alison ------ Alison Pamment Tel: +44 1235 778065 Centre for Environmental Data Analysis Email: [email protected] STFC Rutherford Appleton Laboratory R25, 2.22 Harwell Campus, Didcot, OX11 0QX, U.K. > -----Original Message----- > From: CF-metadata [mailto:[email protected]] On Behalf > Of Karl Taylor > Sent: 08 March 2016 15:56 > To: [email protected] > Subject: Re: [CF-metadata] Confusing skin temperature and interface > temperature > > Hi all, > > I, for one, would find Martin's wording an improvement and with the > addition of "subskin" temperature complete (adding "subskin" to one of > Martin's sentences): > > "More specific terms, namely sea_surface_skin_temperature, > sea_surface_subskin_temperature, and surface_termperature are available > for the skin, subskin, and interface temperature. respectively." > > thanks, > Karl > > On 3/8/16 1:47 AM, [email protected] wrote: > > Hello All, > > > > Karl has raised an objection to the wording ".... not the skin ...." which > > was > carried over from the current CF Standard Name definition for > sea_surface_temperature in my suggested update. The update is intended > to correct a currently erroneous reference to "surface_temperature" as skin > temperature. Karl's objection, which also applies to the existing definition > (and appears to date back to v1 fo the list), could be accomodated by a > simple change: > > > > 'Sea surface temperature is usually abbreviated as "SST". It > > is the temperature of sea water near the surface (including > > the part under sea-ice, if any). More specific terms > sea_surface_skin_temperature and surface_temperature > > are available for the skin and interface > > temperature respectively. For the temperature of sea water at a > > particular depth or layer, a data variable of > > sea_water_temperature with a vertical coordinate axis should > > be used.' > > > > regards, > > Martin > > > > > > > > ________________________________________ > > From: CF-metadata [[email protected]] on behalf of cf- > [email protected] [[email protected]] > > Sent: 08 March 2016 01:46 > > To: [email protected] > > Subject: CF-metadata Digest, Vol 155, Issue 13 > > > > Send CF-metadata mailing list submissions to > > [email protected] > > > > To subscribe or unsubscribe via the World Wide Web, visit > > http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata > > or, via email, send a message with subject or body 'help' to > > [email protected] > > > > You can reach the person managing the list at > > [email protected] > > > > When replying, please edit your Subject line so it is more specific > > than "Re: Contents of CF-metadata digest..." > > > > > > Today's Topics: > > > > 1. Re: Confusing skin temperature and interface temperature > > (Karl Taylor) > > > > > > ---------------------------------------------------------------------- > > > > Message: 1 > > Date: Mon, 7 Mar 2016 17:47:05 -0800 > > From: Karl Taylor <[email protected]> > > To: Peter Minnett <[email protected]>, > > [email protected], [email protected] > > Cc: [email protected], [email protected], > > [email protected], [email protected] > > Subject: Re: [CF-metadata] Confusing skin temperature and interface > > temperature > > Message-ID: <[email protected]> > > Content-Type: text/plain; charset="utf-8"; Format="flowed" > > > > Dear Peter, Craig and all, > > > > For observations I am not arguing that all the different ocean > > temperature definitions aren't needed. In describing observations I > > understand that skin and surface temperature are not identical. My > > statement was that by construction (almost all) current models assume > > that the temperature is vertically uniform (i.e., the water is perfectly > > mixed and homogeneous) throughout the upper most layer, so in *those* > > models the statement that the "sea_surface_temperature" is "not the skin > > or interface temperature" is *wrong*. > > > > The CF standard name description of "sea_surface_temperature" is > > somewhat vague by design: "the temperature of sea water near the > > surface". Because it is vague, it *could* defensibly be used to > > represent any more precisely defined near-surface temperature, including > > "sea_surface_skin_temperature", "sea_surface_subskin_temperature", or > > "sea_surface_foundation_temperature". > > > > Even for observations it would be wrong to say "sea water near the > > surface is not the skin temperature". > > > > Since skin temperature is near the surface and sea_surface_temperature > > is vague, it might in fact be the same as skin temperature (e.g., if > > sea_surface_temperature in fact recorded the conductive > > diffusion-dominated sub-layer at a depth of approximately 10-20 > > micrometers below the air-sea interface). Again, usually in models, > > sea_surface_temperature most emphatically does provide the model's > best > > (only!) estimate of skin temperature. > > > > If the description were changed to read: > > "It is the temperature of sea water near the surface (including the part > > under sea-ice, if any), and not necessarily the skin temperature". > > I would be happy. > > > > Better yet, why not include in the discussion the following points: > > > > 1) surface temperature, sea_surface_temperature, > > sea_surface_skin_temperature, sea_surface_subskin_temperature, and > > sea_surface_foundation_temperature are all terms that might apply to the > > temperature of sea water. > > 2) When the temperature represents a horizontal spatial average, > > surface_temperature represents the mean of the temperature over all > > surface types in the domain, whereas the other temperatures do not. > > 3) The sea_surface_temperature is imprecise because it represents a > > near-surface temperature sampled within (or averaged over) the portion > > of the column extending from the surface down to perhaps several > > meters. In many ocean models, the temperature does not vary in that > > portion of the column so sea_surface_temperature might be the > > appropriate standard_name. Note that in this case, if part of the > > horizontal domain represented by this temperature is under sea ice, the > > temperature would not be the same as surface_temperature (which > would > > include contributions from the surface of the sea ice). > > 4) The other CF standard names for ocean temperatures have more precise > > definitions, and so those names should be used whenever they apply. > > > > best regards, > > Karl > > > > > > > > On 3/7/16 7:06 AM, Peter Minnett wrote: > >> Dear Alison, Craig, Karl et al., > >> > >> I have refrained from entering this discussion until now as Craig has > >> made the points carefully and succinctly. But I think there's a > >> fundamental issue at stake about what these definitions are for. > >> > >> My view is that definitions such as these are intended to provide a > >> framework for communication that accurately but briefly represents our > >> best understanding of the physics of the upper ocean and lower > >> atmosphere. Thus, the definitions should not be constrained, or > >> adapted, to reflect our current measurement or modelling capabilities > >> as these, we expect, will improve with time. If, at some point in the > >> future, we learn something new about how the thermal structure of the > >> upper ocean behaves, then maybe the definitions will have to be > >> revised, but for now I believe our definitions should be based on our > >> understanding of the physical behavior of sea water near the air-sea > >> interface. And this is what we tried to achieve with the GHRSST > >> definitions. > >> > >> Best regards, > >> > >> Peter > >> > >> -------------------------------------------------------- > >> Peter J. Minnett > >> Professor, Department of Ocean Sciences > >> Speaker, RSMAS School Council. > >> Rosenstiel School of Marine and Atmospheric Science > >> University of Miami > >> 4600 Rickenbacker Causeway > >> Miami, FL 33149-1031, USA > >> > >> Chairman, Science Team of the Group for High Resolution Sea-Surface > >> Temperature (GHRSST) > >> > >> Tel: +1 (305) 421-4104 Fax: +1 (305) 421-4696 > >> email: [email protected] > >> http://www.rsmas.miami.edu/people/faculty-index/?p=peter-minnett > >> https://www.ghrsst.org/ > >> > >> > >> > >> > >> > >> On 3/7/2016 6:41 AM, [email protected] wrote: > >>> Dear Craig and Karl, > >>> > >>> Thanks both for your comments. It is clear that we need some more > >>> discussion on this topic. I will be making an update to the standard > >>> name table tomorrow but will defer any changes to the sea surface > >>> temperature names until we can all agree a position on this. > >>> > >>> Best wishes, > >>> > >>> Alison > >>> > >>> ------ > >>> > >>> Alison Pamment Tel: +44 1235 778065 > >>> > >>> Centre for Environmental Data Analysis Email: > >>> [email protected] <mailto:[email protected]> > >>> > >>> STFC Rutherford Appleton Laboratory > >>> > >>> R25, 2.22 > >>> > >>> Harwell Campus, Didcot, OX11 0QX, U.K. > >>> > >>> *From:*Craig Donlon [mailto:[email protected]] > >>> *Sent:* 07 March 2016 02:18 > >>> *To:* Pamment, Alison (STFC,RAL,RALSP) > >>> *Cc:* [email protected]; [email protected]; Kenneth Casey; > >>> Peter Minnett; Anne O'Caroll; Edward Armstrong > >>> *Subject:* Re: [CF-metadata] Confusing skin temperature and interface > >>> temperature > >>> > >>> Dear Alison and Karl: > >>> > >>> Thanks for the discussion here. The key issue is that model teams > >>> need to be more precise as to which SST variable is being used. As > >>> more advanced systems begin to fully couple ocean and atmosphere, > >>> begin to perform radiance assimilation etc the need for each of the > >>> different SST variables becomes readily apparent. > >>> > >>> I would not like to see any of the current CF SST definitions watered > >>> down in the manner proposed. But rather to ask Karl to define what > >>> he means by SST in the modelling context that he is working? > >>> > >>> Then we may hope to resolve the issue efficiently. > >>> > >>> Regards > >>> > >>> Craig > >>> > >>> -- > >>> > >>> *** Sent from my iPhone *** > >>> > >>> -- > >>> > >>> Dr Craig Donlon > >>> > >>> Sentinel-3 Mission Scientist, > >>> > >>> Principal Scientist for Oceans and Ice > >>> > >>> European Space Agency/ESTEC > >>> > >>> Keplerlaan 1, 2201 AZ > >>> > >>> Noordwijk > >>> > >>> The Netherlands > >>> > >>> > >>> > >>> e: [email protected] > >>> > >>> t: +31 (0)715 653687 > >>> > >>> f: +31 (0)715 655675 > >>> > >>> m: +31 (0)627 013244 > >>> > >>> Skype: crazit > >>> > >>> > >>> On 3 Mar 2016, at 19:53, <[email protected] > >>> <mailto:[email protected]>> <[email protected] > >>> <mailto:[email protected]>> wrote: > >>> > >>> Dear Karl, > >>> > >>> Thanks for your comments on this. Clearly we need to get this > >>> right before I make any changes in the standard name table. > >>> > >>> I recall that the sea surface skin, subskin and foundation > >>> temperatures were introduced primarily to describe satellite > >>> radiometer data because the existing sea_surface_temperature name > >>> was too vague. I have the impression that modellers sometimes use > >>> the word ?skin? as being synonymous with the interface at the > >>> bottom of the atmosphere and I think that was probably the > >>> intention behind its use in the current definition. By contrast, > >>> the observational community have a very specific definition for > >>> the sea skin: ?the conductive diffusion-dominated sub-layer at a > >>> depth of approximately 10 - 20 micrometers below the air-sea > >>> interface?. So I think there is scope for some confusion here > >>> since the more specific sea surface temperature names were > >>> introduced. > >>> > >>> As far as standard name definitions are concerned, the main thing > >>> is to ensure we provide clear guidance as to when a particular > >>> name should be used and to explain the relationships between > >>> similar names. I take your point that some models may be > >>> deliberately formulated to have sea_surface_temperature (by which > >>> I assume you mean the top layer of the model) the same as the > >>> interface temperature. I assume you would still label it with a > >>> standard name of sea_surface_temperature, even though in this > >>> case it would be directly comparable with a variable with > >>> standard name surface_temperature and we should probably explain > >>> that in the definition. > >>> > >>> Do models ever output variables that you would actually want > >>> label as ?skin?, ?subskin? or ?foundation? temperatures (as > >>> defined in the existing standard names)? If not, then perhaps it > >>> is best to simply note in the definition that the other names > >>> exist and that they have very specific definitions. This avoids > >>> the issue around the word ?skin?. > >>> > >>> These points would then lead to a definition something like the > >>> following: > >>> > >>> ?Sea surface temperature is usually abbreviated as "SST". It is > >>> the temperature of sea water near the surface (including the part > >>> under sea-ice, if any), and is not necessarily the same as the > >>> interface temperature at the bottom of the atmosphere, whose > >>> standard name is surface_temperature. Some models are formulated > >>> such that sea_surface_temperature and surface_temperature are the > >>> same in ice free sea areas. The standard names > >>> sea_surface_skin_temperature, sea_surface_subskin_temperature > and > >>> sea_surface_foundation_temperature can be used to describe the > >>> temperature in specific layers close to the sea surface and are > >>> often used to describe satellite observations. For the > >>> temperature of sea water at a particular depth or layer, a > >>> standard name of sea_water_temperature with a vertical coordinate > >>> axis should be used.? > >>> > >>> Does that sound OK? Does it include all the necessary information? > >>> > >>> Best wishes, > >>> > >>> Alison > >>> > >>> ------ > >>> > >>> Alison Pamment Tel: +44 1235 778065 > >>> > >>> Centre for Environmental Data Analysis Email: > >>> [email protected] <mailto:[email protected]> > >>> > >>> STFC Rutherford Appleton Laboratory > >>> > >>> R25, 2.22 > >>> > >>> Harwell Campus, Didcot, OX11 0QX, U.K. > >>> > >>> *From:*CF-metadata [mailto:[email protected]] > *On > >>> Behalf Of *Karl Taylor > >>> *Sent:* 02 March 2016 20:26 > >>> *To:* [email protected] <mailto:[email protected]> > >>> *Subject:* Re: [CF-metadata] Confusing skin temperature and > >>> interface temperature > >>> > >>> Dear Alison and all, > >>> > >>> For "sea_surface_temperature", there is a problem stating > >>> definitively that it is "not the skin or interface temperature". > >>> In most models the skin and interface temperatures over ice-free > >>> (i.e., open) ocean are indeed the same as sea_surface_temperature > >>> (by construction). I think it would be more accurate (and less > >>> misleading) to say it is "not *necessarily* the skin or interface > >>> temperature". You could also add to the list > >>> "sea_surface_foundation_temperature" here because in models it > >>> too is often the same as sea_surface_temperature". Models are > >>> evolving, so this might not indefinitely be the case. > >>> > >>> thanks, > >>> Karl > >>> > >>> > >>> On 3/2/16 9:40 AM, > >>> <mailto:[email protected]>[email protected] > wrote: > >>> > >>> Dear Martin, All, > >>> > >>> No objections have been received to the proposed definition > >>> change and it is now accepted for publication in the standard > >>> name table. > >>> > >>> The name will in future appear as: > >>> > >>> sea_surface_temperature (canonical units: K) > >>> > >>> ?Sea surface temperature is usually abbreviated as "SST". It > >>> is the temperature of sea water near the surface (including > >>> the part under sea-ice, if any), not the skin or interface > >>> temperature, whose standard names are > >>> sea_surface_skin_temperature and surface_temperature, > >>> respectively. For the temperature of sea water at a > >>> particular depth or layer, a data variable of > >>> sea_water_temperature with a vertical coordinate axis should > >>> be used.? > >>> > >>> In response to Martin?s proposal I received an email from > >>> Craig Donlon (original proposer of many of the current > >>> sea_surface_X_temperature names). Craig and his team support > >>> the Martin?s proposal and additionally point out an error > >>> that occurs in the definition of the following names: > >>> > >>> sea_surface_skin_temperature > >>> > >>> sea_surface_subskin_temperature > >>> > >>> in which the first sentence reads ?The surface called > >>> "surface" means the lower boundary of the atmosphere? even > >>> though the temperatures are not in fact measured at the > >>> sea-air boundary. The suggestion is to delete the initial > >>> sentence from the definitions. I note also that a similar > >>> situation currently exists with the standard name > >>> sea_surface_foundation_temperature even though that > >>> temperature generally refers to a depth of 1 ? 5 m below the > >>> sea surface. > >>> > >>> I agree with Craig that the sentence should be deleted. I > >>> think it was probably included by accident because most > >>> ?surface? standard names do indeed refer to the interface > >>> between the bottom of the atmosphere and whatever lies > >>> beneath. I plan to remove the sentence from the definitions > >>> of these three names at the next standard name table update > >>> unless any objections are received in the meantime. > >>> > >>> Best wishes, > >>> > >>> Alison > >>> > >>> ------ > >>> > >>> Alison Pamment Tel: +44 1235 778065 > >>> > >>> Centre for Environmental Data Analysis Email: > >>> [email protected] <mailto:[email protected]> > >>> > >>> STFC Rutherford Appleton Laboratory > >>> > >>> R25, 2.22 > >>> > >>> Harwell Campus, Didcot, OX11 0QX, U.K. > >>> > >>> *From:*Pamment, Alison (STFC,RAL,RALSP) > >>> *Sent:* 03 February 2016 15:32 > >>> *To:* Juckes, Martin (STFC,RAL,RALSP); > >>> [email protected] <mailto:[email protected]> > >>> *Subject:* RE: Confusing skin temperature and interface > >>> temperature > >>> > >>> Dear Martin, > >>> > >>> Thank you for pointing this out. I agree that since the > >>> introduction of the very precisely defined > >>> sea_surface_skin_temperature name, the definition of the more > >>> generic name is confusing. I agree with your suggested > >>> amendment and unless anyone objects within the next seven > >>> days the change will be accepted and added at the next update > >>> of the standard name table. > >>> > >>> Best wishes, > >>> > >>> Alison > >>> > >>> *From:*Juckes, Martin (STFC,RAL,RALSP) > >>> *Sent:* 02 February 2016 16:07 > >>> *To:* > >>> <mailto:[email protected]>[email protected]; > >>> Pamment, Alison (STFC,RAL,RALSP) > >>> *Subject:* Confusing skin temperature and interface temperature > >>> > >>> Hello All, > >>> > >>> The CF Standard Name sea_surface_temperature includes the > >>> statement that it is "./... not the skin temperature, whose > >>> standard name is surface_temperature/". The last phrase here > >>> is incorrect: the standard name of the skin temperature > >>> is/sea_surface_skin_temperature/, not /surface_temperature/. > >>> Can the definition be modified to read ".. /not the skin or > >>> interface temperature, whose standard names are > >>> sea_surface_skin_temperature and surface_temperature > >>> respectively/"? > >>> > >>> regards, > >>> Martin > >>> > >>> > >>> > >>> > >>> > >>> _______________________________________________ > >>> > >>> CF-metadata mailing list > >>> > >>> [email protected] <mailto:[email protected]> > >>> > >>> http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata > >>> <https://secure- > web.cisco.com/1tuODHTnfdQ3sBhVdVtvQSRkyRmHIs9nvDADRmlFauFKml3q > k9suIDfvTfeaDbFvmmncKjtjbyKsUT696sKnywSfQl2F1aeExC32Qo65czODh371 > F727iG8p6JM2cyauMFthLR0SGuMC4dnKAqFSEJcOQeeGq5Pd614l- > Dkqt4fDmUBH9kxN1hyWZNw7jc7tAXy-CpfArd- > _VhK8fgSClUBCVXnHSWo9Jun3YWYnrYPt_7Is6tg_F6fj_p0NXmsD90_RrEjmMt > GFwm9ht_KSX7DVwq52ngiWskMa01iQgRVMYMv- > wFTQ18pJDOkdYlDOhNPblHz41WQS3FThueazQyMeq1LTXB8BarYL7nFT3nsw/ > https%3A%2F%2Furldefense.proofpoint.com%2Fv2%2Furl%3Fu%3Dhttp- > 3A__mailman.cgd.ucar.edu_mailman_listinfo_cf- > 2Dmetadata%26d%3DCwMGaQ%26c%3Dy2w- > uYmhgFWijp_IQN0DhA%26r%3D0HNmq- > PhkIBTp_Xo64DQvi0_M2lu06wIxOH1nNI6YOw%26m%3DON5hyu_fyflzAK5_2 > U73gXzNgww_VIv7ajRFMgifvOg%26s%3DbUyWPFXYNpVO8MbSCXOZsv6jLb > QxCa3zOgGs7XlKk4I%26e%3D> > >>> > >>> _______________________________________________ > >>> CF-metadata mailing list > >>> [email protected] <mailto:[email protected]> > >>> http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata > >>> <https://secure- > web.cisco.com/1tuODHTnfdQ3sBhVdVtvQSRkyRmHIs9nvDADRmlFauFKml3q > k9suIDfvTfeaDbFvmmncKjtjbyKsUT696sKnywSfQl2F1aeExC32Qo65czODh371 > F727iG8p6JM2cyauMFthLR0SGuMC4dnKAqFSEJcOQeeGq5Pd614l- > Dkqt4fDmUBH9kxN1hyWZNw7jc7tAXy-CpfArd- > _VhK8fgSClUBCVXnHSWo9Jun3YWYnrYPt_7Is6tg_F6fj_p0NXmsD90_RrEjmMt > GFwm9ht_KSX7DVwq52ngiWskMa01iQgRVMYMv- > wFTQ18pJDOkdYlDOhNPblHz41WQS3FThueazQyMeq1LTXB8BarYL7nFT3nsw/ > https%3A%2F%2Furldefense.proofpoint.com%2Fv2%2Furl%3Fu%3Dhttp- > 3A__mailman.cgd.ucar.edu_mailman_listinfo_cf- > 2Dmetadata%26d%3DCwMGaQ%26c%3Dy2w- > uYmhgFWijp_IQN0DhA%26r%3D0HNmq- > PhkIBTp_Xo64DQvi0_M2lu06wIxOH1nNI6YOw%26m%3DON5hyu_fyflzAK5_2 > U73gXzNgww_VIv7ajRFMgifvOg%26s%3DbUyWPFXYNpVO8MbSCXOZsv6jLb > QxCa3zOgGs7XlKk4I%26e%3D> > >>> > >>> This message and any attachments are intended for the use of the > addressee or addressees only. > >>> The unauthorised disclosure, use, dissemination or copying (either in > whole or in part) of its > >>> content is not permitted. > >>> If you received this message in error, please notify the sender and > delete it from your system. > >>> Emails can be altered and their integrity cannot be guaranteed by the > sender. > >>> Please consider the environment before printing this email. > > -------------- next part -------------- > > An HTML attachment was scrubbed... > > URL: <http://mailman.cgd.ucar.edu/pipermail/cf- > metadata/attachments/20160307/103d84ac/attachment.html> > > > > ------------------------------ > > > > Subject: Digest Footer > > > > _______________________________________________ > > CF-metadata mailing list > > [email protected] > > http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata > > > > > > ------------------------------ > > > > End of CF-metadata Digest, Vol 155, Issue 13 > > ******************************************** > > _______________________________________________ > > CF-metadata mailing list > > [email protected] > > http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata > > _______________________________________________ > CF-metadata mailing list > [email protected] > http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata _______________________________________________ CF-metadata mailing list [email protected] http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
