Dear Andreas,
Thank you. The name is accepted and will be included in the next standard name table update.
Best wishes,
Alison
------
Alison Pamment Tel: +44 1235 778065
Centre for Environmental Data Analysis Email: alison.pamment at stfc.ac.uk
STFC Rutherford Appleton Laboratory
R25, 2.22
Harwell Campus, Didcot, OX11 0QX, U.K.
> -----Original Message-----
> From: Bodas-Salcedo, Alejandro
> [mailto:alejandro.bodas at metoffice.gov.uk]
> Sent: 03 March 2016 10:37
> To: Pamment, Alison (STFC,RAL,RALSP); cf-metadata at cgd.ucar.edu
> Subject: RE: [CF-metadata] New standard name for aerosol single scattering
> albedo
>
> Dear Alison,
>
> Thanks for looking into this. I am happy with the name and definition.
>
> Regards,
>
> Alejandro
>
>
> > -----Original Message-----
> > From: alison.pamment at stfc.ac.uk [mailto:alison.pamment at stfc.ac.uk]
> > Sent: 02 March 2016 17:40
> > To: Bodas-Salcedo, Alejandro; cf-metadata at cgd.ucar.edu
> > Subject: RE: [CF-metadata] New standard name for aerosol single
> scattering albedo
> >
> > Dear Alejandro and Markus,
> >
> > Just picking up on Alejandro's proposal. I like the suggestion of
> > single_scattering_albedo_in_air_due_to_ambient_aerosol_particles
> (canonical
> > units:1 (dimensionless)).
> > This is indeed consistent with the syntax of existing names. The
> > "due_to_ambient_aersol_particles" phrase should be understood to mean
> that the
> > scattering is indeed due to the particulate component of the aerosol and
> not the
> > surrounding air. We have standard definition text that should make all
> that clear:
> > ' "Single scattering albedo" is the fraction of radiation in an incident light
> beam
> > scattered by the particles of an aerosol reference volume for a given
> wavelength. It
> > is the ratio of the scattering and the extinction coefficients of the aerosol
> particles in
> > the reference volume. A coordinate variable with a standard name of
> > radiation_wavelength or radiation_frequency should be included to
> specify either the
> > wavelength or frequency. "Aerosol" means the system of suspended
> liquid or solid
> > particles in air (except cloud droplets) and their carrier gas, the air itself.
> > "Ambient_aerosol" means that the aerosol is measured or modelled at the
> ambient
> > state of pressure, temperature and relative humidity that exists in its
> immediate
> > environment. "Ambient aerosol particles" are aerosol particles that have
> taken up
> > ambient water through hygroscopic growth. The extent of hygroscopic
> growth
> > depends on the relative humidity and the composition of the particles. To
> specify the
> > relative humidity and temperature at which the quantity described by the
> standard
> > name applies, provide scalar coordinate variables with standard names of
> > "relative_humidity" and "air_temperature". The specification of a physical
> process
> > by the phrase "due_to_" process means that the quantity named is a single
> term in a
> > sum of terms which together compose the general quantity named by
> omitting the
> > phrase.'
> >
> > Alejandro, if you are happy with this then I think the name can be
> accepted for
> > inclusion in the standard name table.
> >
> > Best wishes,
> > Alison
> >
> > ------
> > Alison Pamment Tel: +44 1235 778065
> > Centre for Environmental Data Analysis Email:
> alison.pamment at stfc.ac.uk
> > STFC Rutherford Appleton Laboratory
> > R25, 2.22
> > Harwell Campus, Didcot, OX11 0QX, U.K.
> >
> >
> >
> > > -----Original Message-----
> > > From: CF-metadata [mailto:cf-metadata-bounces at cgd.ucar.edu] On
> Behalf
> > > Of Bodas-Salcedo, Alejandro
> > > Sent: 20 January 2016 09:37
> > > To: cf-metadata at cgd.ucar.edu
> > > Subject: Re: [CF-metadata] New standard name for aerosol single
> scattering
> > > albedo
> > >
> > > Dear Markus,
> > >
> > > Thanks for your comment. I'm happy with the change to a population of
> > > particles. As you say, it's a more practical definition. I find the first
> sentence
> > > a bit difficult, though. What about the following?
> > >
> > >
> > > Definition: Fraction of radiation in an incident light beam scattered by
> the
> > > particles of an aerosol reference volume as a function of wavelength. It
> is
> > > the ratio of the scattering and the extinction coefficients of the aerosol
> > > particles in the reference volume. A coordinate of radiation_wavelength
> or
> > > radiation_frequency should be included to specify either the
> wavelength or
> > > frequency.
> > >
> > > Regarding the humidity state, perhaps we should follow the definition
> for
> > > the extinction coefficient, and use the name
> > >
> > > single_scattering_albedo_in_air_due_to_ambient_aerosol_particles
> > >
> > > My only reservation is that this seems to refer to the optical properties
> of
> > > aerosols plus the molecular atmosphere, not only aerosols.
> > >
> > > Regards,
> > >
> > > Alejandro
> > >
> > >
> > > > -----Original Message-----
> > > > From: CF-metadata [mailto:cf-metadata-bounces at cgd.ucar.edu] On
> > > Behalf Of
> > > > Markus Fiebig
> > > > Sent: 19 January 2016 12:49
> > > > To: cf-metadata at cgd.ucar.edu
> > > > Subject: Re: [CF-metadata] New standard name for aerosol single
> > > scattering albedo
> > > >
> > > > Dear Alejandro,
> > > >
> > > > after reading your mail, I was surprised to realise that
> > > > aerosol_single_scattering_albedo in fact hadn't been defined yet.
> > > >
> > > > However, the definition you propose seems to me rather unusual. You
> > > define the
> > > > single scattering albedo with respect to a single particle as ratio of
> > > > cross-sections, i.e. as truly microscale property. From the multitude of
> > > > particles contained in an aerosol, how do you determine which particle
> > > you refer to?
> > > >
> > > > From my experience, it's more usual to define the single scattering
> albedo
> > > as
> > > > ratio of scattering and extinction coefficient of a particle population,
> i.e.
> > > an
> > > > effective property for the ensemble of particles contained in the
> aerosol.
> > > How
> > > > about this:
> > > >
> > > > Definition: Fraction of radiation in an incident light beam interacting
> with
> > > the
> > > > particles of an aerosol reference volume and scattered by these
> particles
> > > as a
> > > > function of wavelength. It is the ratio of the scattering and the
> extinction
> > > > coefficients of the aerosol particles in the reference volume. A
> coordinate
> > > of
> > > > radiation_wavelength or radiation_frequency should be included to
> > > specify either
> > > > the wavelength or frequency.
> > > >
> > > > Having said that, should we also consider to include the humidity state
> of
> > > the
> > > > aerosol? That would require relative_humidity as additional coordinate
> > > variable.
> > > >
> > > > Best regards,
> > > > Markus
> > > >
> > > > Am 19.01.2016 um 10:47 schrieb Bodas-Salcedo, Alejandro:
> > > > > Dear All,
> > > > >
> > > > > I'd like to propose a new standard name, which as far as I can see
> doesn't
> > > > currently exist in the CF table:
> > > > >
> > > > > Name: aerosol_single_scattering_albedo
> > > > > Units: 1
> > > > > Description: Fraction of radiation scattered out of a pencil of radiation
> > > after one
> > > > encounter with an aerosol particle for a given wavelength. It is the
> ratio
> > > between the
> > > > scattering cross-section and the extinction cross-section. A coordinate
> of
> > > > radiation_wavelength or radiation_frequency should be included to
> > > specify either the
> > > > wavelength or frequency.
> > > > >
> > > > >
> > > > > Thanks,
> > > > >
> > > > > Alejandro
> > > > >
> > > >
> > > > --
> > > > 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
Received on Thu Mar 03 2016 - 09:26:59 GMT
