Dear Jonathan, All,
No further comments have been received so the four new names proposed for FAFMIP are now accepted and will be published in the April update of the standard name table.
sea_water_added_conservative_temperature, degC
' The quantity with standard name sea_water_added_conservative_temperature is a passive tracer in an ocean model whose surface flux does not come from the atmosphere but is imposed externally upon the simulated climate system. The surface flux is expressed as a heat flux and converted to a passive tracer increment as if it were a heat flux being added to conservative temperature. The passive tracer is transported within the ocean as if it were conservative temperature. The passive tracer is zero in the control climate of the model. The passive tracer records added heat, as described for the CMIP6 FAFMIP experiment (doi:10.5194/gmd-9-3993-2016), following earlier ideas. Conservative Temperature is defined as part of the Thermodynamic Equation of Seawater 2010 (TEOS-10) which was adopted in 2010 by the International Oceanographic Commission (IOC). Conservative Temperature is specific potential enthalpy (which has the standard name sea_water_specific_potential_enthalpy) divided by a fixed value of the specific
heat capacity of sea water, namely cp_0 = 3991.86795711963 J kg-1 K-1. Conservative Temperature is a more accurate measure of the "heat content" of sea water, by a factor of one hundred, than is potential temperature. Because of this, it can be regarded as being proportional to the heat content of sea water per unit mass. Reference: www.teos-10.org; McDougall, 2003 doi: 10.1175/1520-0485(2003)033<0945:PEACOV>2.0.CO;2.'
sea_water_added_potential_temperature, degC
'The quantity with standard name sea_water_added_potential_temperature is a passive tracer in an ocean model whose surface flux does not come from the atmosphere but is imposed externally upon the simulated climate system. The surface flux is expressed as a heat flux and converted to a passive tracer increment as if it were a heat flux being added to potential temperature. The passive tracer is transported within the ocean as if it were potential temperature. The passive tracer is zero in the control climate of the model. The passive tracer records added heat, as described for the CMIP6 FAFMIP experiment (doi:10.5194/gmd-9-3993-2016), following earlier ideas. Potential temperature is the temperature a parcel of air or sea water would have if moved adiabatically to sea level pressure.'
sea_water_redistributed_conservative_temperature, degC
'The quantity with standard name sea_water_redistributed_conservative_temperature is a passive tracer in an ocean model which is subject to an externally imposed perturbative surface heat flux. The passive tracer is initialised to the conservative temperature in the control climate before the perturbation is imposed. Its surface flux is the heat flux from the atmosphere, not including the imposed perturbation, and is converted to a passive tracer increment as if it were being added to conservative temperature. The passive tracer is transported within the ocean as if it were conservative temperature. The passive tracer records redistributed heat, as described for the CMIP6 FAFMIP experiment (doi:10.5194/gmd-9-3993-2016), following earlier ideas.Conservative Temperature is defined as part of the Thermodynamic Equation of Seawater 2010 (TEOS-10) which was adopted in 2010 by the International Oceanographic Commission (IOC). Conservative Temperature is specific potential enthalpy (which has the standard name sea_
water_specific_potential_enthalpy) divided by a fixed value of the specific heat capacity of sea water, namely cp_0 = 3991.86795711963 J kg-1 K-1. Conservative Temperature is a more accurate measure of the "heat content" of sea water, by a factor of one hundred, than is potential temperature. Because of this, it can be regarded as being proportional to the heat content of sea water per unit mass. Reference: www.teos-10.org; McDougall, 2003 doi: 10.1175/1520-0485(2003)033<0945:PEACOV>2.0.CO;2.'
sea_water_redistributed_potential_temperature, degC
'The quantity with standard name sea_water_redistributed_conservative_temperature is a passive tracer in an ocean model which is subject to an externally imposed perturbative surface heat flux. The passive tracer is initialised to the conservative temperature in the control climate before the perturbation is imposed. Its surface flux is the heat flux from the atmosphere, not including the imposed perturbation, and is converted to a passive tracer increment as if it were being added to conservative temperature. The passive tracer is transported within the ocean as if it were conservative temperature. The passive tracer records redistributed heat, as described for the CMIP6 FAFMIP experiment (doi:10.5194/gmd-9-3993-2016), following earlier ideas.Conservative Temperature is defined as part of the Thermodynamic Equation of Seawater 2010 (TEOS-10) which was adopted in 2010 by the International Oceanographic Commission (IOC). Conservative Temperature is specific potential enthalpy (which has the standard name sea_
water_specific_potential_enthalpy) divided by a fixed value of the specific heat capacity of sea water, namely cp_0 = 3991.86795711963 J kg-1 K-1. Conservative Temperature is a more accurate measure of the "heat content" of sea water, by a factor of one hundred, than is potential temperature. Because of this, it can be regarded as being proportional to the heat content of sea water per unit mass. Reference: www.teos-10.org; McDougall, 2003 doi: 10.1175/1520-0485(2003)033<0945:PEACOV>2.0.CO;2.'
Best wishes,
Alison
------
Alison Pamment Tel: +44 1235 778065
NCAS/Centre for Environmental Data Archival Email: alison.pamment at stfc.ac.uk
STFC Rutherford Appleton Laboratory
R25, 2.22
Harwell Oxford, Didcot, OX11 0QX, U.K.
-----Original Message-----
From: Pamment, Alison (STFC,RAL,RALSP)
Sent: 20 March 2018 12:08
To: 'Jonathan Gregory' <j.m.gregory at reading.ac.uk>; cf-metadata at cgd.ucar.edu
Subject: RE: [CF-metadata] standard names for FAFMIP passive tracers
Dear Jonathan,
Thank you for proposing these FAFMIP names and for providing such clear definitions. I recall our previous discussion of OMIP names in which we established the necessity of using Celsius rather than Kelvin for certain ocean model temperature quantities, so the canonical units of these are fine. The names themselves are also fine - I think it is clear that these are not the usual model prognostic variables and they are unlikely to be mistaken as such. I'm happy with these names as they currently stand - unless we receive any objections in the next seven days they will be accepted for inclusion in the standard name table and published in the April update.
Best wishes,
Alison
------
Alison Pamment Tel: +44 1235 778065
NCAS/Centre for Environmental Data Archival Email: alison.pamment at stfc.ac.uk
STFC Rutherford Appleton Laboratory
R25, 2.22
Harwell Oxford, Didcot, OX11 0QX, U.K.
-----Original Message-----
From: CF-metadata [mailto:cf-metadata-bounces at cgd.ucar.edu] On Behalf Of Jonathan Gregory
Sent: 19 March 2018 18:32
To: cf-metadata at cgd.ucar.edu
Subject: [CF-metadata] standard names for FAFMIP passive tracers
Dear all
Martin and Alison have pointed out that four standard names needed for FAFMIP haven't yet been proposed. That was my oversight. I would now like to propose:
sea_water_added_conservative_temperature, degC A passive tracer in an ocean model whose surface flux does not come from the atmosphere but is imposed externally upon the simulated climate system. The surface flux is expressed as a heat flux and converted to a passive tracer increment as if it were a heat flux being added to conservative temperature.
The passive tracer is transported within the ocean as if it were conservative temperature. The passive tracer is zero in the control climate of the model.
The passive tracer records added heat, as described for the CMIP6 FAFMIP experiment (doi:10.5194/gmd-9-3993-2016), following earlier ideas.
** Then repeat the definition of sea_water_conservative_temperature.
sea_water_added_potential_temperature, degC A passive tracer in an ocean model whose surface flux does not come from the atmosphere but is imposed externally upon the simulated climate system. The surface flux is expressed as a heat flux and converted to a passive tracer increment as if it were a heat flux being added to potential temperature. The passive tracer is transported within the ocean as if it were potential temperature. The passive tracer is zero in the control climate of the model.
The passive tracer records added heat, as described for the CMIP6 FAFMIP experiment (doi:10.5194/gmd-9-3993-2016), following earlier ideas.
Potential temperature of sea water is the temperature a parcel of sea water would have if moved adiabatically to sea level pressure.
sea_water_redistributed_conservative_temperature, degC A passive tracer in an ocean model which is subject to an externally imposed perturbative surface heat flux. The passive tracer is initialised to the conservative temperature in the control climate before the perturbation is imposed. Its surface flux is the heat flux from the atmosphere, not including the imposed perturbation, and is converted to a passive tracer increment as if it were being added to conservative temperature. The passivetracer is transported within the ocean as if it were conservative temperature. The passive tracer records redistributed heat, as described for the CMIP6 FAFMIP experiment (doi:10.5194/gmd-9-3993-2016), following earlier ideas.
** Then repeat the definition of sea_water_conservative_temperature.
sea_water_redistributed_potential_temperature, degC A passive tracer in an ocean model which is subject to an externally imposed perturbative surface heat flux. The passive tracer is initialised to the potential temperature in the control climate before the perturbation is imposed. Its surface flux is the heat flux from the atmosphere, not including the imposed perturbation, and is converted to a passive tracer increment as if it were being added to potential temperature. The passive tracer is transported within the ocean as if it were potential temperature. The passive tracer records redistributed heat, as described for the CMIP6 FAFMIP experiment (doi:10.5194/gmd-9-3993-2016), following earlier ideas.
Potential temperature of sea water is the temperature a parcel of sea water would have if moved adiabatically to sea level pressure.
I note that in Table 3 of the paper cited we said "additional" temperature for the standard names, but throughout the rest of the paper we referred to "added"
heat (not "additional"), following earlier literature, and in the existing CF-netCDF data produced for FAFMIP we have used "added" in the standard names.
Hence I think this must have been a change of mind and should be regarded as a mistake in the paper. We will make a note of it on the FAFMIP website once this proposal has been decided upon.
Cheers
Jonathan
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Received on Thu Mar 29 2018 - 08:35:44 BST
