[CF-metadata] New standard name: volume_extinction_coefficient_in_air_due_to_cloud

[Bodas-Salcedo, Alejandro]

Dear CF list,

I'd like to propose the following standard name:

volume_extinction_coefficient_in_air_due_to_cloud
Units: m-1

Definition, following the aerosol extinction coefficient:
The volume extinction coefficient is the fractional change of radiative flux per unit path length. Extinction is the sum of absorption and scattering, sometimes called "attenuation". "Extinction" is the term most commonly used at optical wavelengths whereas "attenuation" is more often used at radio and radar wavelengths. "Cloud" means suspended liquid or ice water droplets.

Regards,

Alejandro
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Dr Alejandro Bodas-Salcedo Earth Observation Research Scientist
Met Office Hadley Centre
FitzRoy Rd Exeter EX1 3PB United Kingdom
Tel: [phone] Fax: [phone]
E-mail: alejandro.bodas at metoffice.gov.uk http://www.metoffice.gov.uk


See our guide to climate change at
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[Fiebig, Markus]

Dear Alejandro,

just one small comment.

We had recently a long discussion concerning wording of a few aerosol variables,
and some results of that discussion would also be relevant for your proposed
variable. You should probably substitute "cloud" with "cloud_particles".
Otherwise, it isn't clear whether you refer only to the cloud particle phase, or
to the whole system of particles and air. Also, you probably want to require a
co-ordinate variable "wavelength" in the definition.

Best regards,
Markus

Post by Bodas-Salcedo, Alejandro
Dear CF list,
volume_extinction_coefficient_in_air_due_to_cloud
Units: m-1
The volume extinction coefficient is the fractional change of radiative flux per unit path length. Extinction is the sum of absorption and scattering, sometimes called "attenuation". "Extinction" is the term most commonly used at optical wavelengths whereas "attenuation" is more often used at radio and radar wavelengths. "Cloud" means suspended liquid or ice water droplets.
Regards,
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.: [phone]
Fax : [phone]
e-mail: Markus.Fiebig at nilu.no
skype: markus.fiebig

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[Bodas-Salcedo, Alejandro]

Dear Markus,

Thanks for your comment. Happy to follow the outcome of the previous discussion, so the name would be:

volume_extinction_coefficient_in_air_due_to_cloud_particles
Units: m-1

Updated definition:
The volume extinction coefficient is the fractional change of radiative flux per unit path length. Extinction is the sum of absorption and scattering, sometimes called "attenuation". "Extinction" is the term most commonly used at optical wavelengths whereas "attenuation" is more often used at radio and radar wavelengths. "Cloud" means suspended liquid or ice water droplets. A coordinate of radiation_wavelength or radiation_frequency should be included to specify either the wavelength or frequency.

Regards,

Alejandro

-----Original Message-----
From: Fiebig, Markus [mailto:Markus.Fiebig at nilu.no]
Sent: Thursday, February 06, 2014 12:10 PM
To: Bodas-Salcedo, Alejandro; 'cf-metadata at cgd.ucar.edu'
volume_extinction_coefficient_in_air_due_to_cloud
Dear Alejandro,
just one small comment.
We had recently a long discussion concerning wording of a few
aerosol variables,
and some results of that discussion would also be relevant
for your proposed
variable. You should probably substitute "cloud" with
"cloud_particles".
Otherwise, it isn't clear whether you refer only to the cloud
particle phase, or
to the whole system of particles and air. Also, you probably
want to require a
co-ordinate variable "wavelength" in the definition.
Best regards,
Markus

Post by Bodas-Salcedo, Alejandro
Dear CF list,
volume_extinction_coefficient_in_air_due_to_cloud
Units: m-1
The volume extinction coefficient is the fractional change

of radiative flux per unit path length. Extinction is the sum
of absorption and scattering, sometimes called "attenuation".
"Extinction" is the term most commonly used at optical
wavelengths whereas "attenuation" is more often used at radio
and radar wavelengths. "Cloud" means suspended liquid or ice
water droplets.

Post by Bodas-Salcedo, Alejandro
Regards,
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.: [phone]
Fax : [phone]
e-mail: Markus.Fiebig at nilu.no
skype: markus.fiebig

[a***@stfc.ac.uk]

Dear Alejandro,

I just stumbled across an old name that was discussed briefly and agreed in 2014 (http://mailman.cgd.ucar.edu/pipermail/cf-metadata/2014/057186.html) , but it seems that I have so far neglected to publish it:

volume_extinction_coefficient_in_air_due_to_cloud_particles (canonical units: m-1)
' The volume extinction coefficient is the fractional change of radiative flux per unit path length. Extinction is the sum of absorption and scattering, sometimes called "attenuation". "Extinction" is the term most commonly used at optical wavelengths whereas "attenuation" is more often used at radio and radar wavelengths. 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. "Cloud particles" means suspended liquid or ice water droplets. A coordinate of radiation_wavelength or radiation_frequency should be included to specify either the wavelength or frequency.'

This name will be included in the update on 17th May.

Best wishes,
Alison

------
Alison Pamment Tel: [phone]
Centre for Environmental Data Analysis Email: ***@stfc.ac.uk
STFC Rutherford Appleton Laboratory
R25, 2.22
Harwell Campus, Didcot, OX11 0QX, U.K.