Dear Eric Yes, I see what you mean. If we could clarify the "defined by" part, would you be content to describe the turbocline as a mixed layer (with appropriate definition)?
Best wishes Jonathan > - ocean_turbocline_thickness in m > The turbocline thickness is similar to the mixed layer thickness but is > estimated in models as the thickness at which the vertical eddy diffusivity > coefficient (resulting from the vertical physics alone) falls below a given > value defined locally. > > You mentioned that this is the same as > ocean_mixed_layer_thickness_defined_by_vertical_tracer_diffusivity. > > But the definition for this one in the CF table is > > "The ocean mixed layer is the upper part of the ocean, regarded as being > well-mixed. The base of the mixed layer defined by temperature, sigma, > sigma_theta, or vertical diffusivity is the level at which the quantity > indicated differs from its surface value by a certain amount. The amount by > which the quantity differs can be specified by a scalar coordinate variable." > > Unlike with temperature or density criteria, the turbocline thickness is not > estimated based on the difference with respect to the vertical diffusivity at > the surface. As written in the definition we gave you, when the vertical > diffusivity falls below a given value defined locally then we are at the > turbocline depth. > > ############################# > > I hope this helps. > > Best regards, > > Eric > > > > > ----- Original Message ----- > From: "Kevin Marsh" <[email protected]> > To: "Eric Boisseson" <[email protected]> > Sent: Tuesday, 13 December, 2016 14:35:48 > Subject: Fwd: [CF-metadata] New standard names for NEMO ocean model output > > Hi Eric, > some feedback on your feedback...feel free to send any responses directly to > the list, or to me if you prefer and i will send the comments to the list. > I think that he's happy with 1, so only need input for 2. and 3., > Thanks, > Kevin > > ----- Forwarded Message ----- > From: "j m gregory" <[email protected]> > To: [email protected] > Sent: Tuesday, 13 December, 2016 13:56:41 > Subject: [CF-metadata] New standard names for NEMO ocean model output > > Dear Kevin > > > 1. bottom_pressure_equivalent_height (m) > > 3. ocean_steric_height (m) > > > > The steric height is estimated as the vertical integral of the density > > (relative to a reference density where T=0K and S=35psu). The bottom > > pressure is the mass of the water column at a given location. > > Ah, I see. > > For > > 3. ocean_steric_height_above_sea_level (m) > I would suggest > > The ocean steric height above sea level measures the change in thickness of > > a column of water when its temperature and salinity are changed from > > standard values of 0°C and 0.035 to the actual values > > > The bottom pressure equivalent height is estimated indirectly as the > > difference between the steric height and the sea level. > > I don't follow that, which sounds like the definition of ocean steric height > again. However your alternative statement of its being the mass of the column > makes sense to me. Going with the latter definition, I would suggest > > sea_water_mass_per_unit_area_expressed_as_thickness > > and presumably you have to state a standard density to be used in this > conversion - what is that? NB sea_water_mass_per_unit_area (kg m-2) is already > a standard name. > > > 2. Instead of "ocean_turbocline_depth (m)" we suggest: > > ocean_turbocline_thickness (m) > > 'The turbocline thickness is similar to the mixed layer thickness but is > > estimated in models as the thickness at which the vertical eddy diffusivity > > coefficient (resulting from the vertical physics alone) falls below a given > > value defined locally.' > > Is there a difference between that and the existing > ocean_mixed_layer_thickness_defined_by_vertical_tracer_diffusivity > ? > > > ratio_of_sea_water_potential_temperature_anomaly_to_relaxation_timescale (K > > s-1) > > > > 'This term is estimated as the deviation of the local sea water potential > > temperature from an ocean model wrt an observation-based climatology (eg > > World Ocean Database) weighted by a user-specified relaxation coefficient > > in s-1 (1/(relaxation timescale)). The relaxation coefficient depends on > > the timescale on which the correction is applied.' > > It seems to me that the last sentence is probably not necessary, since the > previous sentence says the same. > > Best wishes and thanks > > Jonathan > _______________________________________________ > CF-metadata mailing list > [email protected] > http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata ----- End forwarded message ----- _______________________________________________ CF-metadata mailing list [email protected] http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
