[CF-metadata] Clarifying standard names for 'mass_concentration_of_*_dry_aerosol_particles'

Daniel Neumann daniel.neumann at io-warnemuende.de
Thu Jul 13 10:23:34 MDT 2017


Dear Markus, Dear List,

Thank you for your feedback.

 > doesn't make much sense beyond archiving a model output field since 
it doesn't
 > describe any quantity that could be readily observed. Also, the mass
 > concentration of particles containing chemical X is somewhat 
ill-defined. You
 > will find some traces of X in almost all particles of an aerosol 
containing X -
 > so where is the threshold for saying that a particle contains X?
I agree with you.

Thus, it might be reasonable to introduce a new standard name (I like 
the one you suggested. My idea for a name was more complicated :-) )

mass_concentration_of_X_in_dry_aerosol_particles_in_air

for (partly) secondary particulate species, namely nitrate, ammonium, 
mercury, chloride, particulate organic matter, secondary particulate 
organic matter and sulfate. For these species (except for chloride) 
there exists already a standard name like

mass_concentration_of_X_dry_aerosol_particles_in_air


I think (please correct me if I am wrong) that

mass_concentration_of_X_dry_aerosol_particles_in_air

was meant to describe the same. Maybe one could make an alias from it?


Regards,
Daniel



On 12.07.2017 14:32, Markus Fiebig wrote:
> Dear Daniel,
>
> thanks for posting this again, I missed your first posting during vacation.
>
> Coming from the observation community, a name like
>
> mass_concentration_of_X_dry_aerosol_particles_in_air
>
> doesn't make much sense beyond archiving a model output field since it doesn't
> describe any quantity that could be readily observed. Also, the mass
> concentration of particles containing chemical X is somewhat ill-defined. You
> will find some traces of X in almost all particles of an aerosol containing X -
> so where is the threshold for saying that a particle contains X?
>
> To me, it would make much more sense to have names of the type
>
> mass_concentration_of_X_in_dry_aerosol_particles_in_air
>
> This type of name is less ambiguous to understand, and describes a property that
> can in fact be observed.
>
> Best regards,
> Markus
>
>
> Am 11.07.2017 um 21:05 schrieb Daniel Neumann:
>> Dear CF-Meta Mailinglist,
>>
>> I would like to advertise my long question from two weeks ago. Maybe there
>> were no replies because it was to long :-) . Excuse me if I should be wrong
>> with that assumption. The basic questions are:
>>
>> What do these two standard names mean?
>>    (a) mass_concentration_of_ammonium_dry_aerosol_particles_in_air
>>    (b) mass_concentration_of_dry_aerosol_particles_expressed_as_ammonium_in_air
>>
>> What should be the standard name for the mass concentration of atmospheric
>> particulate chloride/ammonium/nitrate/sulfate/...? Should it be like (a), like
>> (b) or something else (e.g. mass_concentrations_of_particulate_ammonium_in_air)?
>>
>> Please find details on the question here:
>> http://mailman.cgd.ucar.edu/pipermail/cf-metadata/2017/059573.html
>>
>> Regards,
>> Daniel
>>
>>
>>
>> On 27.06.2017 14:43, Daniel Neumann wrote:
>>> Dear CF-Mailinglist,
>>>
>>> in a recent proposal (link given below*), Alison and I discussed about the
>>> naming conventions for the mass of specific aerosol particle components.
>>> There seems to be clarification necessary in the descriptions and/or names.
>>> [* recent proposal with discussion:
>>> http://mailman.cgd.ucar.edu/pipermail/cf-metadata/2017/059522.html, look for
>>> "10. mass_concentration_of_chloride_dry_aerosol_particles_in_air (kg m-3)"]
>>>
>>>
>>> Currently, there exist standard names like
>>>> mass_concentration_of_ammonium_dry_aerosol_particles_in_air
>>>> mass_concentration_of_dust_dry_aerosol_particles_in_air
>>>> general form: mass_concentration_of_X_dry_aerosol_particles_in_air
>>> which describe mass concentration of aerosol particles that contain species
>>> X. Thus, this standard name describes not only the mass of species X but also
>>> the mass of other species that are associated with X on particles. In the
>>> past, I thought it would describe the mass of species X only. We think that
>>> there is a need for clarifying this in the description of these standard names.
>>>
>>>
>>> When we now want to quantify the mass of particulate X only (e.g. mass of
>>> particulate chloride, mass of particulate ammonium), we could use the
>>> standard name
>>>> mass_concentration_of_dry_aerosol_particles_expressed_as_X_in_air
>>> However, I see two problems with respect to this naming convention. First, we
>>> get a not-nice name if we want to express the mass concentrations of
>>> particulate ammonium in terms of nitrogen. We needed a standard name like
>>> mass_concentration_of_dry_aerosol_particles_expressed_as_ammonium_expressed_as_nitrogen_in_air
>>> which contains 'expressed' twice.
>>>
>>> Second (but that is my personal feeling only), I use the "X_expressed_as_Y"
>>> formulation only, when there is some relation from Y to X. Or in other words:
>>> when Y is a reasonable measure for X.
>>>> ...organic_matter_..._expressed_as_carbon...
>>>> ...nox_expressed_as_nitrogen...
>>>> ...phytoplankton_expressed_as_phosphorus...
>>> Therefore,
>>> "mass_concentration_of_dry_aerosol_particles_expressed_as_X_in_air" is not a
>>> good choice for a standard name describing the mass of particulate X in my
>>> opinion.
>>>
>>>
>>> An alternative would be to introduce a standard name like
>>>> mass_concentrations_of_particulate_X_in_air
>>>> mass_concentrations_of_particulate_ammonium_in_air
>>>> mass_concentrations_of_particulate_chloride_in_air
>>>
>>> What is your opinion on this topic?
>>>
>>>
>>> Best Regards,
>>> Daniel
>>>
> --
> Dr. Markus Fiebig
> Senior Scientist
> Dept. Atmospheric and Climate Research (ATMOS)
> Norwegian Institute for Air Research (NILU)
> P.O. Box 100
> N-2027 Kjeller
> Norway
>
> Tel.: +47 6389-8235
> Fax : +47 6389-8050
> e-mail: Markus.Fiebig at nilu.no
> skype: markus.fiebig
>
> P Please consider the environment before printing this email and attachments
> _______________________________________________
> CF-metadata mailing list
> CF-metadata at cgd.ucar.edu
> http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata

-- 
Daniel Neumann

Leibniz Institute for Baltic Sea Research Warnemuende
Physical Oceanography and Instrumentation
Seestrasse 15
18119 Rostock
Germany

phone:  +49-381-5197-287
fax:    +49-381-5197-114 or 440
e-mail: daniel.neumann at io-warnemuende.de




More information about the CF-metadata mailing list