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: [email protected] skype: markus.fiebig P Please consider the environment before printing this email and attachments _______________________________________________ CF-metadata mailing list [email protected] http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
