[CF-metadata] standard names for CEOP

From: Jonathan Gregory <j.m.gregory>
Date: Mon, 28 Nov 2005 08:16:11 +0000

Dear Beate

Some comments and suggestions on your proposed standard names. Thanks for
your help.

Cheers

Jonathan


* We already have

- soil_porosity:1
- tendency_of_specific_humidity_due_to_advection:kg kg-1 sec-1
- tendency_of_air_temperature_due_to_advection:K s-1
- tendency_of_atmosphere_water_vapor_content_due_to_convection:kg m-2 s-1
- tendency_of_atmosphere_water_vapor_content:kg m-2 s-1

so no need to add them.

* These look OK to me:

> mass_fraction_of_cloud_condensed_water_in_air:1
> surface_downwelling_photosynthetic_photon_flux_in_air:mol m-2 s-1
> surface_net_upward_radiative_flux
> surface_upwelling_photosynthetic_photon_flux_in_air:mol m-2 s-1
> tendency_of_mass_fraction_of_cloud_condensed_water_in_air_due_to_advection: s-1

* Your "energy in air" variables have dimensions m2 s-2 so should be called
"specific energy density in air" for consistency with the guidelines. The
sum of kinetic energy and enthalpy is dry static energy. What do you mean
by just "energy in air"? Is this moist static energy perhaps? If so, your
three quantities

< energy_in_air; m2 s-2
< sum_of_kinetic_energy_and_enthalpy_in_air; m2 m-2
< kinetic_energy_in_air; m2 s-2

would be

> specific_moist_static_energy_density_in_air:m2 s-2
> specific_dry_static_energy_density_in_air:m2 s-2
> specific_kinetic_energy_density_in_air:m2 s-2

* What do you mean by "dry energy" in

< total_dry_energy_content_of_atmosphere_layer; J m-2
< tendency_of_total_dry_energy_of_atmosphere_layer; W m-2
< atmosphere_dry_energy_content; J m-2

Perhaps it is "dry static energy"? In that case these would probably be

> dry_static_energy_content_of_atmosphere_layer:J m-2
> tendency_of_dry_static_energy_content_of_atmosphere_layer:W m-2
> atmosphere_dry_static_energy_content:J m-2

but in that case you don't need

- sum_of_kinetic_energy_and_enthalpy_content_of_atmosphere_layer; J m-2

* We have atmosphere_energy_content in the table at present, but it is not
really defined what it means. What do you mean by it in

< tendency_of_atmosphere_energy_content:W m-2

Perhaps it's moist static energy as suggested above? In that case we would have

> tendency_of_atmosphere_moist_static_energy_content:W m-2

* What energy is being referred to in these quantities?

- eastward_energy_flux_in_air; W m-1
- upward_energy_flux_in_air; W m-1
- northward_energy_flux_in_air; W m-1

* Since we already have

- convective_cloud_base_altitude:m
- convective_cloud_top_altitude:m

I would rearrange yours as

> convective_cloud_base_height:m
> convective_cloud_top_height:m

"Altitude" is distance above the geoid (mean sea level) and "height" is
distance above the surface.

* Is this both land ice and sea ice?

- ice_area_fraction; 1

* Since you give the explanation (sea 0 land 1 ice 2 fraction) for

- sea_land_ice_area_fraction; 1

it doesn't appear to be an area fraction, but a variable which gives the nature
of the surface. Is that right? If so, I propose we should give it a standard
name of surface_cover, which would be a string variable having possible values
including sea_ice, land_ice and open_sea. You could then encode these as
integers in the data variable (instead of strings) using the flag_meanings and
flag_values attributes. The same variable could be used for
        
- vegetation_type; 1

i.e. the values of surface_type could also encode vegetation types (grass,
needleleaf trees etc.) Burkhardt Rockel needed the same thing and we have just
added land_cover for him. surface_cover would be a generalisation that could
also include sea area.

* By a plain "flux" of matter we mean a mass flux by default e.g. in the
precipitation fluxes. Is the CO2 flux at the surface? If so, instead of

< carbon_dioxide_flux; mole m-2 s-1

we should have

> surface_carbon_dioxide_mole_flux:mol s-2 s-1

* To be more explicit and for consistency with recently added names for field
capacity and wilting point, instead of

< soil_moisture; % (volumetric water content)

I propose

> volume_fraction_of_water_in_soil:1

* In

< eastward_water_vapor_flux_in_air; kg m-2 s-1
< northward_water_vapor_flux_in_air; kg m-2 s-1

I think we could omit "_in_air" since water vapor isn't transported by the
ocean i.e. just

> eastward_water_vapor_flux:kg m-2 s-1
> northward_water_vapor_flux:kg m-2 s-1

These have the same dimensions as the "atmosphere_eastward/northward_
water_vapor_flux_content" variables which you suggest. Are they the same?

* This

< tendency_of_water_vapor_of_atmosphere_layer_due_to_convection; kg m-2 s-1

should be

> tendency_of_water_vapor_content_of_atmosphere_layer_due_to_convection:kg m-2 s-1

* I'm not sure what this means:

- tendency_of_atmosphere_mass_content; kg m-2 s-1

Does it refer to the total mass of the atmosphere?

* For consistency with water_vapor_content_of_atmosphere_layer, we should
have

> tendency_of_water_vapor_content_of_atmosphere_layer:kg m-2 s-1

* What mass is moving in these quantities?

- eastward_mass_flux_in_air; kg m-1 s-1
- northward_mass_flux_in_air; kg m-1 s-1
- upward_mass_flux_in_air; kg m-1 s-1

* I'm unclear what this means

- surface_moisture; kg m-2
Received on Mon Nov 28 2005 - 01:16:11 GMT