Dear Alison,
thanks, those names and definitions are good. I agree that they are ready to go into the standard name list, regards, Martin ________________________________ From: CF-metadata <cf-metadata-boun...@cgd.ucar.edu> on behalf of Alison Pamment - UKRI STFC <alison.pamm...@stfc.ac.uk> Sent: 29 May 2019 15:02 To: CF-metadata (cf-metadata@cgd.ucar.edu) Subject: Re: [CF-metadata] Surfaces under ice vs. above ice : sea water surface vs surface in standard names. Dear Martin, Thank you for reminding me about these proposals. I recall that we had some off-list discussion of these names in February before they were sent to the list. (1) sea_water_pressure_at_sea_water_surface and net_downward_shortwave_flux_at_sea_water_surface. I agree with your suggestions to amend the definitions of these names by replacing 'The surface called "surface" means the lower boundary of the atmosphere' with 'The phrase "sea water surface" means the upper boundary of the liquid portion of an ocean or sea, including the boundary to floating ice if present.' These changes are accepted and will be made in the June update to the standard name table. (2) Stresses at sea water surface I agree with your proposals to introduce 4 new names for stresses at the upper surface of liquid sea water: . downward_x_stress_at_sea_water_surface . downward_y_stress_at_sea_water_surface . downward_x_stress_correction_at_sea_water_surface . downward_y_stress_correction_at_sea_water_surface. Basing the units and definitions on existing names for surface stresses and stress corrections, the first two would be as follows. downward_x_stress_at_sea_water_surface (Canonical units: Pa) ' "Downward" indicates a vector component which is positive when directed downward (negative upward). "x" indicates a vector component along the grid x-axis, positive with increasing x. A downward x stress is a downward flux of momentum towards the positive direction of the model's x-axis. The phrase "sea water surface" means the upper boundary of the liquid portion of an ocean or sea, including the boundary to floating ice if present.' downward_y_stress_at_sea_water_surface (Canonical units: Pa) ' "Downward" indicates a vector component which is positive when directed downward (negative upward). "y" indicates a vector component along the grid y-axis, positive with increasing y. A downward y stress is a downward flux of momentum towards the positive direction of the model's y-axis. The phrase "sea water surface" means the upper boundary of the liquid portion of an ocean or sea, including the boundary to floating ice if present.' We don't currently have any definition for 'stress_correction', but I borrowed from the one for 'flux_correction' in the following: downward_x_stress_correction_at_sea_water_surface (Canonical units: Pa) ' "Downward" indicates a vector component which is positive when directed downward (negative upward). "x" indicates a vector component along the grid x-axis, positive with increasing x. A downward x stress is a downward flux of momentum towards the positive direction of the model's x-axis. A positive correction is downward i.e. added to the ocean. The phrase "sea water surface" means the upper boundary of the liquid portion of an ocean or sea, including the boundary to floating ice if present.' downward_y_stress_correction_at_sea_water_surface (Canonical units: Pa) ' "Downward" indicates a vector component which is positive when directed downward (negative upward). "y" indicates a vector component along the grid y-axis, positive with increasing y. A downward y stress is a downward flux of momentum towards the positive direction of the model's y-axis. A positive correction is downward i.e. added to the ocean. The phrase "sea water surface" means the upper boundary of the liquid portion of an ocean or sea, including the boundary to floating ice if present.' If you are happy with these, then I think all four can be accepted for inclusion in the standard name table. Best wishes, Alison ----------------------------------------------------------------------------------------------------------- Alison Pamment Tel: +44 1235 778065 NCAS/Centre for Environmental Data Analysis Email: alison.pamm...@stfc.ac.uk STFC Rutherford Appleton Laboratory R25, 2.22 Harwell Oxford, Didcot, OX11 0QX, U.K. From: Juckes, Martin (STFC,RAL,RALSP) <martin.juc...@stfc.ac.uk> Sent: 15 May 2019 11:59 To: CF-metadata (cf-metadata@cgd.ucar.edu) <cf-metadata@cgd.ucar.edu>; Pamment, Alison (STFC,RAL,RALSP) <alison.pamm...@stfc.ac.uk> Subject: Re: Surfaces under ice vs. above ice : sea water surface vs surface in standard names. Dear Alison, could you take a look at the request for 4 terms listed below, which I submitted in February. There have been no other comments, but I think these are simple adjustments to existing names, regards, Martin ________________________________________ From: Juckes, Martin (STFC,RAL,RALSP) Sent: 07 February 2019 17:16 To: CF-metadata (mailto:cf-metadata@cgd.ucar.edu) Subject: Surfaces under ice vs. above ice : sea water surface vs surface in standard names. Dear All, while reviewing CMIP6 metadata specifications I came across a few anomalies regarding the distinction between the upper surface of the liquid ocean (which may be under ice) vs. the lower surface of the atmosphere (which would be above the ice). (1) sea_water_pressure_at_sea_water_surface and net_downward_shortwave_flux_at_sea_water_surface; The names of these two terms suggest that they are intended to be different from, for example, surface_net_downward_shortwave_flux. They have been requested by OMIP for diagnostics which are intended to represent the air/sea or ice/sea interface, on the air/ice interface. The problem is that the descriptions use the standard phrase 'The surface called "surface" means the lower boundary of the atmosphere', which is wrong in this case. Can this be changed to: 'The phrase "sea water surface" means the upper boundary of the liquid portion of an ocean or sea, including the boundary to floating ice if present.' (2) surface_downward_x/y_stress and surface_downward_x/y_stress_correction; There is nothing wrong with these terms, but they have been wrongly used to represent stresses applied to the liquid ocean. To correct this we need four new terms. I propose using the "_at_sea_water_surface" construction, based on the two terms above: . downward_x_stress_at_sea_water_surface . downward_y_stress_at_sea_water_surface . downward_x_stress_correction_at_sea_water_surface . downward_y_stress_correction_at_sea_water_surface As above, the description should include the sentence: 'The phrase "sea water surface" means the upper boundary of the liquid portion of an ocean or sea, including the boundary to floating ice if present.' regards, Martin _______________________________________________ CF-metadata mailing list CF-metadata@cgd.ucar.edu http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata _______________________________________________ CF-metadata mailing list CF-metadata@cgd.ucar.edu http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
