Hello Trevor,

I totally agree that we should stop using 'salinity' from now on.  I also agree 
that virtually all post-1983 (not 1980: it took 5 years to get the 1978 
Equation of State published by UNESCO) data labelled 'salinity' are in fact 
'practical_salinity'.  However, as an oceanographic data centre we have 
salinity data going back to the early 1900s and other centres such as ICES have 
data going back further than that. These have been determined by a variety of 
methodologies but are mostly chemical titrations or a variety of algorithmic 
determinations from conductivity that are significantly different from the 
PSS-78 scale. Replacing 'salinity' by 'practical_salinity' re-labels these 
data, which I believe is wrong.

We certainly need to get 'practical_salinity' names in place and alter the 
definition for salinity to indicate that it means 'salt content by any method' 
with wording to strongly discourage its use for post-1983 data unless the data 
are known to be 'non-practical' (which exist: we have some).  We also need to 
explain to the community that unless they change the labels on their data that 
are practical salinity from 'salinity' to 'practical_salinity' then their data 
will be regarded as useless for many physical oceanographic applications.

Cheers, Roy.

-----Original Message-----
From: trevor.mcdoug...@csiro.au [mailto:trevor.mcdoug...@csiro.au] 
Sent: 05 October 2011 00:12
To: Lowry, Roy K.; j.m.greg...@reading.ac.uk; paul.dur...@csiro.au
Cc: CF-metadata@cgd.ucar.edu; r...@eos.ubc.ca; King, Brian A.; 
paul.bar...@csiro.au; rainer.feis...@io-warnemuende.de; 
stephen.griff...@noaa.gov
Subject: RE: [CF-metadata] new TEOS-10 standard names

Dear all,

   At the risk of repeating ourselves, because there are now (at least) three 
different salinities, it is now ambiguous and confusing to call any salinity 
"Salinity".  The Announcement of TEOS-10 that is now appearing in all 22 
oceanographic journals specifically recommends that the use of the word 
"Salinity" cease immediately, and that either the words "Practical Salinity" or 
"Absolute Salinity" be used.  The reason of course is to minimise ambiguity. 

   So this is where the community (including CF-metadata) will have to end up:- 
we have been requested to do so by IOC, SCOR and IAPSO.  So we may as well do 
it now, in my view.

   Note that all ocean models run to date have used Practical Salinity as their 
"Salinity" variable,, and all equations of state since 1980 have been in terms 
of Practical Salinity.  So there is no slight-of-hand in calling these 
variables "Practical Salinity"; rather it is just being specific as to what 
this type of salinity always has been.  That is "Practical Salinity" is simply 
the long-hand name of what we have been calling "Salinity" for 30 years.  

   Trevor


-----Original Message-----
From: Lowry, Roy K. [mailto:r...@bodc.ac.uk] 
Sent: Wednesday, 5 October 2011 1:43 AM
To: Jonathan Gregory; Durack, Paul (CMAR, Hobart)
Cc: McDougall, Trevor (CMAR, Hobart); CF-metadata@cgd.ucar.edu; 
r...@eos.ubc.ca; King, Brian A.; Barker, Paul (CMAR, Hobart); 
rainer.feis...@io-warnemuende.de; stephen.griff...@noaa.gov
Subject: RE: [CF-metadata] new TEOS-10 standard names

Dear All,

My feelings on this were (and still are) comfort with the addition of 
'practical_salinity' names, but significant discomfort with the replacement of 
'salinity' by 'practical_salinity' through deprecation of 'salinity'.

Cheers, Roy.

-----Original Message-----
From: cf-metadata-boun...@cgd.ucar.edu 
[mailto:cf-metadata-boun...@cgd.ucar.edu] On Behalf Of Jonathan Gregory
Sent: 04 October 2011 14:13
To: paul.dur...@csiro.au
Cc: trevor.mcdoug...@csiro.au; CF-metadata@cgd.ucar.edu; r...@eos.ubc.ca; King, 
Brian A.; paul.bar...@csiro.au; rainer.feis...@io-warnemuende.de; 
stephen.griff...@noaa.gov
Subject: Re: [CF-metadata] new TEOS-10 standard names

Dear Paul

Alison (the manager of standard names) hasn't "ruled" yet on their inclusion,
but I believe that the discussion concluded with no objections to adding
the practical salinity names. It seems safe to assume they will be put in the
table in due course.

Best wishes

Jonathan
_______________________________________________
CF-metadata mailing list
CF-metadata@cgd.ucar.edu
http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
-- 
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@cgd.ucar.edu
http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata

Reply via email to