Dear Markus and Jonathan,
I fully agree with Markus with respect to having a structure that is
expandable by "pm10" or similar size descriptors.
I would rather drop "aerosol" and keep "in_air". The reason is that we
define the concentration of "ammonium in dry particles" (mass) in "air"
(per volume). This is also suggested by
http://cfconventions.org/Data/cf-standard-names/docs/guidelines.html#medium
Using "mass_concentration_of_ammonium_in_dry_aerosol_particles" might be
miss-interpreted as the concentration of "ammonium" in "dry
aerosol_particles" (per volume or per mass) - and not in air.
I also see that
? mass_concentration_of_ammonium_in_dry_particles_in_air
is not ambiguous because it might mean
? concentration of "ammonium in dry particles" in "air".
or
? concentration of "ammonium" in "dry particles in per".
However,
? mass_concentration_of_particulate_ammonium_in_air
is lacking the expandability by "pm10" (or whatever).
Regards,
Daniel
On 05.01.2018 09:53, Markus Fiebig wrote:
> Dear Jonathan and Daniel,
>
> just to make an attempt to throw in my 5 cents here:
>
> By definition, the term "aerosol" already means the system of the particles
> together with their carrier gas which, in this context of the atmosphere, is
> air. Thus, "aerosol_particles_in_air" includes the air twice. We may consider
> simply to omit the "in_air", and would end up with:
>
> mass_concentration_of_ammonium_in_dry_aerosol_particles
>
> That way, we'd make clear that only the particle phase is meant, but leave the
> option open for further additions such as "pm10", e.g.
> mass_concentration_of_ammonium_in_pm10_dry_aerosol_particles.
>
> Best regards,
> Markus
>
>
> Am 04.01.2018 um 17:44 schrieb Jonathan Gregory:
>> Dear Daniel
>>
>> I see. So the new names would be of the form
>> mass_concentration_of_ammonium_in_dry_aerosol_particles_in_air
>> I think that might be liable to misunderstanding. It could mean the mass
>> concentration of the ammonium within the aerosol particles, rather than
>> within the air. Your earlier suggestion
>> mass_concentration_of_particulate_ammonium_in_air
>> does not have that drawback.
>>
>> Best wishes
>>
>> Jonathan
>>
>> ----- Forwarded message from Daniel Neumann <daniel.neumann at io-warnemuende.de> -----
>>
>>> Date: Wed, 3 Jan 2018 22:46:55 +0100
>>> From: Daniel Neumann <daniel.neumann at io-warnemuende.de>
>>> To: cf-metadata at cgd.ucar.edu
>>> Subject: Re: [CF-metadata] Fwd: Re: Clarifying standard names for
>>> 'mass_concentration_of_*_dry_aerosol_particles'
>>> User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101
>>> Thunderbird/52.5.0
>>>
>>> Dear Jonathan,
>>>
>>>> OK. If experts are unanimous in their conviction that the existing names will
>>>> never be needed for the meaning that they appear to have, I agree that they
>>>> should become aliases of the new names, which convey the correct meaning.
>>>> I'm sure this change could be made.
>>> Great.
>>>
>>>> Alison Pamment is in charge of the updates
>>>> as you know and I expect she will consider as it soon as she has time. I think
>>>> that a complete list of the new and old names would be useful - that may
>>>> already be in one of your emails, perhaps.
>>> I didn't include a full list yet. I will create one and send it
>>> around the next days.
>>>
>>> After reading one of the past mailing list posts again and talking
>>> to a former colleague: it might be better to just include an "_in_"
>>> between "X" and "dry_aerosol_particles" in the new names (and maybe
>>> remove aerosol) instead of creating names like
>>> "...particulate_X_in_air". This first version with "_in_" is better
>>> expandable, when particle size fractions like PM10 should be
>>> considered in future (like
>>> "..._X_in_PM10_dry_aerosol_particles_in_air").
>>>
>>> Thank you very much.
>>>
>>> Best,
>>> Daniel
>>>
>>>
>>>> Best wishes and thanks
>>>>
>>>> Jonathan
>>>>
>>>> ----- Forwarded message from Daniel Neumann <daniel.neumann at io-warnemuende.de> -----
>>>>
>>>>> Date: Wed, 3 Jan 2018 17:07:45 +0100
>>>>> From: Daniel Neumann <daniel.neumann at io-warnemuende.de>
>>>>> To: cf-metadata at cgd.ucar.edu
>>>>> Subject: Re: [CF-metadata] Clarifying standard names for
>>>>> 'mass_concentration_of_*_dry_aerosol_particles'
>>>>> User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101
>>>>> Thunderbird/52.5.0
>>>>>
>>>>> Dear Jonathan,
>>>>>
>>>>>> I understand. That's tricky, [...]
>>>>> Yes :-) .
>>>>>
>>>>>
>>>>>> We could define apple to mean orange in
>>>>>> future, for the sake of the existing datasets,
>>>>>> but only if we are certain that no-one will
>>>>>> ever want to talk about apples.
>>>>> I am not aware of any situation in which someone actually meant to
>>>>> talk about apples. Markus Fiebig from the World Data Centre for
>>>>> Aerosols wrote the same
>>>>> (http://mailman.cgd.ucar.edu/pipermail/cf-metadata/2017/059588.html).
>>>>> I talked to two former colleagues, who confirmed it as well.
>>>>> Therefore, it is quite save to assume that nobody talks about
>>>>> apples.
>>>>>
>>>>>
>>>>>> We could just define and start using the new names,
>>>>>> and be aware that the CMIP5 datasets used the
>>>>>> wrong names (because the CF process somehow
>>>>>> made a mistake), without defining aliases. Would
>>>>>> that be acceptable?
>>>>> With respect to my personal usage of the respective standard names I
>>>>> am fine with just defining new standard names. I also see that it is
>>>>> the simplest solution for the moment considering the work effort
>>>>> needed to additionally define aliases.
>>>>>
>>>>> But, we might run into trouble (and cause confusion), if both
>>>>> standard names - apple and orange - are used to describe oranges.
>>>>> People, who used "apple" in the past, probably keep using "apple" to
>>>>> describe oranges because they are not aware of the changes. People
>>>>> who look up standard names for their new data sets might also end up
>>>>> with "apple" for describing an orange if "apple" is not marked as
>>>>> deprecated. Also people comparing data sets following the old and
>>>>> the new conventions (e.g. CMIP5 and CMIP6) might not be aware of
>>>>> this discussion. Hence, I would prefer to define aliases.
>>>>>
>>>>> Would it be feasible with respect to the required work, to define
>>>>> aliases for all the ambiguous standard names? How could I support
>>>>> this process? There seem to be 100 to 110 standard names involved:
>>>>>
>>>>> - atmosphere_mass_content_of_X_dry_aerosol_particles (15)
>>>>> - tendency_of_atmosphere_mass_content_of_X_dry_aerosol_particles*
>>>>> (78, maybe less)
>>>>> - mass_concentration_of_X_dry_aerosol_particles_in_air (15)
>>>>> - tendency_of_mass_concentration_of_X_dry_aerosol_particles_in_air (1)
>>>>>
>>>>>
>>>>> Best,
>>>>> Daniel
>>>>>
>>>>>
>>>>>
>>>>> On 03.01.2018 14:40, Jonathan Gregory wrote:
>>>>>> Dear Daniel
>>>>>>
>>>>>>>>> Is it feasible to rename all affected standard names?
>>>>>>>> It would be feasible (using aliases) but is it necessary? It seems to me that
>>>>>>>> your question has identified that there should be a distinction between e.g.
>>>>>>>> mass_concentration_of_particulate_X_in_air
>>>>>>>> and
>>>>>>>> mass_concentration_of_X_dry_aerosol_particles_in_air
>>>>>>>> for X=ammonium etc. These are different quantities: the former refers to the
>>>>>>>> mass of ammonium only, the latter to the dry mass of the aerosol of that type.
>>>>>>>> That is, we need new names for CMIP6, not aliases.
>>>>>>> Yes, there should be a distinction between both standard names.
>>>>>>> However, the latter name has been used as synonym for the first name
>>>>>>> up till now (e.g. in CMIP5 or in a data set I published recently).
>>>>>>> Additionally, the latter name has no real application - at least I
>>>>>>> am not aware of an application (neither for model nor for
>>>>>>> measurement data). Therefore, it might be reasonable for backward
>>>>>>> compatibility to use aliases.
>>>>>> I understand. That's tricky, because we've established that the second name
>>>>>> is a valid concept but not correct. When we use aliases, it's because we've
>>>>>> decided on a clearer, more consistent or more precise formulation of the
>>>>>> name, but in this case, it seemed that we called something an apple when
>>>>>> it ought to have been called an orange. We could define apple to mean orange
>>>>>> in future, for the sake of the existing datasets, but only if we are certain
>>>>>> that no-one will ever want to talk about apples.
>>>>>>
>>>>>> We could just define and start using the new names, and be aware that the
>>>>>> CMIP5 datasets used the wrong names (because the CF process somehow made a
>>>>>> mistake), without defining aliases. Would that be acceptable?
>>>>>>
>>>>>> Best wishes
>>>>>>
>>>>>> Jonathan
>>>>>> _______________________________________________
>>>>>> CF-metadata mailing list
>>>>>> CF-metadata at cgd.ucar.edu
>>>>>> http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
>>>>> _______________________________________________
>>>>> CF-metadata mailing list
>>>>> CF-metadata at cgd.ucar.edu
>>>>> http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
>>>> ----- End forwarded message -----
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>> ----- End forwarded message -----
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> --
> 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
> _______________________________________________
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--
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
Received on Mon Jan 08 2018 - 01:41:44 GMT
