Dear Ian and Dan Thanks for your email. I believe we agree on the following (omitting the descriptions for the sake of the overview).
Rename: water_flux_into_ocean water_flux_into_ocean_from_rivers water_volume_transport_into_ocean_from_rivers wind_mixing_energy_flux_into_ocean water_flux_into_ocean_without_flux_correction (proposal agreed with Martina) by replacing "ocean" with "sea_water". Include Newtonian relaxation in the definitions of water_flux_into_sea_water, water_flux_out_of_sea_water (T5), water_flux_out_of_sea_ice_and_sea_water (T3), virtual_salt_flux_into_sea_water (T6). New names: T1 water_flux_out_of_sea_water_due_to_sea_ice_thermodynamics (kg m-2 s-1) T3 water_flux_out_of_sea_ice_and_sea_water (kg m-2 s-1) T4 minus_one_times_water_flux_into_sea_water_from_rivers (kg m-2 s-1) T5 water_flux_out_of_sea_water (kg m-2 s-1) T7 ocean_mixed_layer_thickness_defined_by_vertical_tracer_diffusivity (m) T8 heat_flux_into_sea_water_due_to_newtonian_relaxation (W m-2) T9 water_flux_out_of_sea_water_due_to_newtonian_relaxation (kg m-2 s-1) T12 model_level_number_at_base_of_ocean_mixed_layer_defined_by_sigma_theta (1) T13 depth_at_maximum_upward_derivative_of_sea_water_potential_temperature (m) T15 ocean_integral_of_sea_water_potential_temperature_wrt_depth_expressed_as_heat_content (J m-2) T17 sea_ice_albedo (1) U2 bolus_sea_water_x_velocity (m s-1) U3 x_derivative_of_ocean_rigid_lid_pressure (N m-3) V2 bolus_sea_water_y_velocity (m s-1) V3 y_derivative_of_ocean_rigid_lid_pressure (N m-3) W2 vertical_sea_water_temperature_diffusivity (m2 s-1) W4 vertical_sea_water_momentum_diffusivity (m2 s-1) W5 vertical_sea_water_momentum_diffusivity_due_to_convection (m2 s-1) W6 vertical_sea_water_salinity_diffusivity (m2 s-1) G4 angle_of_rotation_from_east_to_x (degree) G5 angle_of_rotation_from_east_to_y (degree) G6 cell_area (m2) G7 model_level_number_at_sea_floor (1) Others are either agreed to be equivalent to existing names, or discussed below (T6, T10, T11, W3, W7, G1-3). T3: This quantity includes rivers, flux adjustment and relaxation. Without these i.e. only the fluxes at the surface of the sea ice and sea water, the name would be surface_upward_water_flux, since "surface" means "bottom of atmosphere" in effect. We also agreed that T2 is surface_upward_water_flux, over the open ocean i.e. it is P-E where there is no sea-ice. These would be distinguished by cell_methods. T2 is "where ice_free_sea", but if sea-ice is included there is no need for "where" because it applies to the whole gridbox. You can also have "where sea_ice", which would mean the precipitation, evaporation and sublimation from the sea-ice surface. T4: I agree with you that, though inelegant, this is preferable to using the scale_factor. That's intended for packing, not for defining the sign of the quantity. T6: In your email you explain this as just being -T5*SSS (I think I am right to put in minus, since T5 is upward, and your original proposal for T6 is downward). This is related to the salinity flux, which is -T5*SSS/density. That being so, your word "virtual", which has the virtue of being often used, may be best to indicate it's not really a physical salt flux. So for consistency with T5 I would now propose virtual_salt_flux_into_sea_water (kg m-2 s-1). T8, T9. I agree with your insertion of "newtonian". T10. Following T6, I would now suggest virtual_salt_flux_into_sea_water_due_to_newtonian_relaxation (kg m-2 s-1). T11. Things should have the same standard name if they are intended to be compared. They need different standard names if you want to distinguish them. So the choice depends on the application, to some extent. I think that sea_surface_height_above_geoid is OK for the quantity derived from the rigid lid, as used in CMIP3, but if you want to show where it comes from, my modified suggestion of yours would be ocean_rigid_lid_pressure_expressed_as_sea_surface_height_above_geoid. We don't currently have a standard name of ocean_rigid_lid_pressure but it might plausibly be proposed. We have other uses of "expressed as". What would you prefer? T13. We haven't put "depth" in other "ocean depth" names so I've omitted it from your proposal. T14. We have a standard name of plain "depth" meaning distance below the surface, which is what you want, I think. It's fine to give it a coordinate of sea_water_potential_temperature. If there is another quantity with that standard name, they just have to have different variable names. Good solution! There is a symmetry about having both sea_water_potential_temperature with a coordinate of depth, and vice-versa. My only reservation is that the standard name of the data variable doesn't indicate it's in the ocean, but I think that's OK. The coord variable implies this, and anyway "depth" is really independent of medium. T15. "ocean" seems a bit unnecessary and it's only there to indicate the integral is through the whole depth of the ocean, as contrasted with a layer. We make this distinction in many standard names, however, and I'd like to get rid of it, but that should be a separate proposal. U3. A slight simplification of your latest version; I hope that's OK. N m-3 and Pa m-1 are both fine, being equivalent! W3. Is this also temperature rather than tracer? W4. You are right, we have not made this distinction; we have not used the word "viscosity" at all so far because of the potential ambiguity. W7. As alternative to introducing the term "lateral" we could perhaps call this xy, to mean the coordinate plane. In other contexts we use the word "horizontal" to mean this (as it usually is) but a vertical component of something horizontal would certainly be a mysterious concept! Why do you prefer "part" to "component"? I think vertical_component_of_sea_water_tracer_xy_diffusivity would be intelligible. G1-G3. I like your suggestion of "coordinate index". That gives us magnitude_of_derivative_of_distance_wrt_x_coordinate_index (m) magnitude_of_derivative_of_distance_wrt_y_coordinate_index (m) magnitude_of_derivative_of_distance_wrt_model_level_number (m) but I wonder whether we might be better off with x_distance, y_distance and depth? Although this is repetition, "distance" is rather a vague word and that might clarify the picture. Since they are magnitudes it doesn't matter whether it is depth or height, and depth seems more intuitive for an ocean model. What do you think? G4. The sign convention anticlockwise=positive should be stated in the definition, as you say. G6. I did prefer "area" earlier but you have changed my mind. G7. Yes, you are right in thinking that the proposed change of the CF cell_measures attribute, as described in our original email would need a trac ticket raised, with a sponsor etc? This applies likewise to G1-G3, which could also be cell_measures. Best wishes Jonathan _______________________________________________ CF-metadata mailing list [email protected] http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
