Number density standard names

[areinecke]

Description

I cannot find number density standard names.

Solution

The number densities of N, N2, O, O2, NO, Ar, He, H, and anomalous oxygen are not defined in the CCPP standard, however, following the convention, I propose the following:

Standard Name	Units	Description
number_density_of_nitrogen_atom	m⁻³	Number density of neutral atomic nitrogen (N) in air
number_density_of_nitrogen_atom_from_climatology	m⁻³	Climatological number density of atomic nitrogen (N), e.g., from MSIS
number_density_of_nitrogen_molecule	m⁻³	Number density of molecular nitrogen (N₂) in air
number_density_of_nitrogen_molecule_from_climatology	m⁻³	Climatological number density of molecular nitrogen (N₂), e.g., from MSIS
number_density_of_oxygen_atom	m⁻³	Number density of neutral atomic oxygen (O) in air
number_density_of_oxygen_atom_from_climatology	m⁻³	Climatological number density of atomic oxygen (O), e.g., from MSIS
number_density_of_oxygen_molecule	m⁻³	Number density of molecular oxygen (O₂) in air
number_density_of_oxygen_molecule_from_climatology	m⁻³	Climatological number density of molecular oxygen (O₂), e.g., from MSIS
number_density_of_nitric_oxide	m⁻³	Number density of nitric oxide (NO) in air
number_density_of_nitric_oxide_from_climatology	m⁻³	Climatological number density of nitric oxide (NO), e.g., from MSIS
number_density_of_argon	m⁻³	Number density of argon (Ar) in air
number_density_of_argon_from_climatology	m⁻³	Climatological number density of argon (Ar), e.g., from MSIS
number_density_of_helium	m⁻³	Number density of helium (He) in air
number_density_of_helium_from_climatology	m⁻³	Climatological number density of helium (He), e.g., from MSIS
number_density_of_hydrogen_atom	m⁻³	Number density of neutral atomic hydrogen (H) in air
number_density_of_hydrogen_atom_from_climatology	m⁻³	Climatological number density of atomic hydrogen (H), e.g., from MSIS
number_density_of_anomalous_oxygen_atom	m⁻³	Number density of energetic, non-thermal atomic oxygen as defined in MSIS
number_density_of_anomalous_oxygen_atom_from_climatology	m⁻³	Climatological number density of anomalous energetic oxygen, e.g., from MSIS
number_density_of_neutral_air	m⁻³	Total number density of neutral air, including all neutral constituents
number_density_of_neutral_air_from_climatology	m⁻³	Climatological total number density of neutral air, e.g., from MSIS

[climbfuji]

Thanks @areinecke.

As noticed, there are no existing standard names for these in the repository. We are checking the other models using CCPP (in particular UFS) if there are similar or conflicting names that haven't been committed back to the ESM standard names repository yet. @dustinswales will provide an update here shortly.

[dustinswales]

@areinecke My apologies for the delay.
We don't have any of these fields in the UWM physics, and I have no objections to these new names.
One small question. Should we specify in_air for the non climo based fields? (Maybe someday we would need in_cloud or in_plume, or in_... and need to distinguish)

[mkavulich]

@dustinswales My thinking is that there's already an implicit in_air for most standard names already if they don't specify a medium, so I don't think that's necessary.

[areinecke]

Sorry for the delay too, I have ongoing issues with being notified by github when I'm tagged in something...

I don't have any preference on in_air, however, simplicity is better so I agree with @mkavulich.

One thing that was brought to my attention about this table is that the qualifiers are used inconsistently and the molecule is used too specificly. Should it be nitric_oxide_molecule and helium_atom and argon_atom

There is also the question of ion species. For example, number_density_of_<XX>_ion where is hydrogen, oxygen_molecule, nitric_oxide, oxygen, nitrogen, cluster; number_density_of_electron, number_density_of_ions, electron_temperature, ion_temperature. I'm definitely not an ionspheric expert so there may be more or disagreement over these names.

[mkavulich]

One thing that was brought to my attention about this table is that the qualifiers are used inconsistently and the molecule is used too specificly. Should it be nitric_oxide_molecule and helium_atom and argon_atom

My thinking is that "molecular" should be implicit in all cases, given that the vast majority of contexts will be referring to a particular substance in its molecular form. Given this potential complication, I'll suggest this modified version of your proposed table:

Standard Name	Units	Description
number_density_of_atomic_nitrogen	m⁻³	Number density of neutral atomic nitrogen (N) in air
number_density_of_atomic_nitrogen_from_climatology	m⁻³	Climatological number density of atomic nitrogen (N), e.g., from MSIS
number_density_of_nitrogen	m⁻³	Number density of molecular nitrogen (N₂) in air
number_density_of_nitrogen_from_climatology	m⁻³	Climatological number density of molecular nitrogen (N₂), e.g., from MSIS
number_density_of_atomic_oxygen	m⁻³	Number density of neutral atomic oxygen (O) in air
number_density_of_atomic_oxygen_from_climatology	m⁻³	Climatological number density of atomic oxygen (O), e.g., from MSIS
number_density_of_oxygen	m⁻³	Number density of molecular oxygen (O₂) in air
number_density_of_oxygen_from_climatology	m⁻³	Climatological number density of molecular oxygen (O₂), e.g., from MSIS
number_density_of_nitric_oxide	m⁻³	Number density of nitric oxide (NO) in air
number_density_of_nitric_oxide_from_climatology	m⁻³	Climatological number density of nitric oxide (NO), e.g., from MSIS
number_density_of_argon	m⁻³	Number density of argon (Ar) in air
number_density_of_argon_from_climatology	m⁻³	Climatological number density of argon (Ar), e.g., from MSIS
number_density_of_helium	m⁻³	Number density of helium (He) in air
number_density_of_helium_from_climatology	m⁻³	Climatological number density of helium (He), e.g., from MSIS
number_density_of_atomic_hydrogen	m⁻³	Number density of neutral atomic hydrogen (H) in air
number_density_of_atomic_hydrogen_atom	m⁻³	Climatological number density of atomic hydrogen (H), e.g., from MSIS
number_density_of_anomalous_oxygen	m⁻³	Number density of energetic, non-thermal atomic oxygen as defined in MSIS
number_density_of_anomalous_oxygen_from_climatology	m⁻³	Climatological number density of anomalous energetic oxygen, e.g., from MSIS
number_density_of_neutral_air	m⁻³	Total number density of neutral air, including all neutral constituents
number_density_of_neutral_air_from_climatology	m⁻³	Climatological total number density of neutral air, e.g., from MSIS

There is also the question of ion species.

I could envision the above table being extended with some simple rules: prefix any substance with ionized_ and include a suffix for the ionization level if needed, e.g.:

• number_density_of_ionized_nitrogen_-1
• number_density_of_ionized_atomic_hydrogen_+1

I suspect this will not cover all use cases but I can't think of an exception off the top of my head.

[mkavulich]

@areinecke Just checking back in on this, I know you've had trouble getting GitHub notifications but I hope you have a chance to review my response.

[areinecke]

@areinecke Just checking back in on this, I know you've had trouble getting GitHub notifications but I hope you have a chance to review my response.

Deferring to @cabarton for the naming question, he will be able to make a much more informed comment.

[cabarton]

My thinking is that "molecular" should be implicit in all cases, given that the vast majority of contexts will be referring to a particular substance in its molecular form.

In terms of the upper atmosphere at least, the opposite is true: most of these are atomic. Nitrogen and oxygen are the only ambiguous names in the list. The "molecule" qualifier would only be needed twice for N2 and O2. The rest are either atomic or a molecule with no ambiguity (e.g. nitric oxide).

We could also do o1, o2, n1o1, he1, etc. to get around the molecular vs atomic ambiguity. But I understand that the standard could be to use the full names rather than formulas.

I don't mind prefixing the species with ionized_. We probably wouldn't need the net charge except in very rare cases, if at all.

[mkavulich]

@cabarton I understand that upper atmospheric physics/chemistry are different, but given that the standard names dictionary is meant to be common to earth systems as a whole, I think it's fair to say that contexts using "atomic" substances by default are in the minority. That said, there is currently no precedent as the existing chemistry variables are all more specific molecular names (e.g. o2). This would be consistent with your follow-up proposal to just use abbreviations (o1, o2, etc.) The only caveat is that the current names all use an implicit rather than explicit 1 to indicate singlet atoms in a molecule; would this be acceptable or would the lack of a 1 leave things too ambiguous?

Standard Name	Units	Description
number_density_of_n	m⁻³	Number density of neutral atomic nitrogen (N) in air
number_density_of_n_from_climatology	m⁻³	Climatological number density of atomic nitrogen (N), e.g., from MSIS
number_density_of_n2	m⁻³	Number density of molecular nitrogen (N₂) in air
number_density_of_n2_from_climatology	m⁻³	Climatological number density of molecular nitrogen (N₂), e.g., from MSIS
number_density_of_o	m⁻³	Number density of neutral atomic oxygen (O) in air
number_density_of_o_from_climatology	m⁻³	Climatological number density of atomic oxygen (O), e.g., from MSIS
number_density_of_o2	m⁻³	Number density of molecular oxygen (O₂) in air
number_density_of_o2_from_climatology	m⁻³	Climatological number density of molecular oxygen (O₂), e.g., from MSIS
number_density_of_no	m⁻³	Number density of nitric oxide (NO) in air
number_density_of_no_from_climatology	m⁻³	Climatological number density of nitric oxide (NO), e.g., from MSIS
number_density_of_ar	m⁻³	Number density of argon (Ar) in air
number_density_of_ar_from_climatology	m⁻³	Climatological number density of argon (Ar), e.g., from MSIS
number_density_of_he	m⁻³	Number density of helium (He) in air
number_density_of_he_from_climatology	m⁻³	Climatological number density of helium (He), e.g., from MSIS
number_density_of_h	m⁻³	Number density of neutral atomic hydrogen (H) in air
number_density_of_h	m⁻³	Climatological number density of atomic hydrogen (H), e.g., from MSIS
number_density_of_anomalous_oxygen	m⁻³	Number density of energetic, non-thermal atomic oxygen as defined in MSIS
number_density_of_anomalous_oxygen_from_climatology	m⁻³	Climatological number density of anomalous energetic oxygen, e.g., from MSIS
number_density_of_neutral_air	m⁻³	Total number density of neutral air, including all neutral constituents
number_density_of_neutral_air_from_climatology	m⁻³	Climatological total number density of neutral air, e.g., from MSIS

[mkavulich]

@cabarton @areinecke Just checking in to see if you've had a chance to review my updated proposal

[cabarton]

If there is no precedent, it seems simpler and minimizes ambiguity to use the chemical formulas as you described. I am tentatively okay with making 1 implicit for single atoms since I can't immediately think of any ambiguities that we would have to worry about for this use case.