Dear Alison and Markus,
since the size distribution names overlap with some of the names proposed by Damien Boulanger from the IGAS project where I'm also involved, I'd like to comment on your name 16:
On 12/18/2014 04:25 PM, alison.pamment at stfc.ac.uk wrote:
> 16. Thank you for the additional explanation of the size distribution names - I hadn't fully understood how these properties are calculated. Of your two proposed solutions, I think the first is most elegant:
>
> log10_size_interval_based_number_size_distribution_of_dried_aerosol_particles_at_stp_in_air (m-3)
>
> "The particle number size distribution is the number concentration of aerosol particles, normalised to the decadal logarithmic size interval the concentration applies to, as a function of particle diameter. Depending on the measurement method, one coordinate variable such as "electrical_mobility_particle_diameter", "optical_particle diameter", or "aerodynamic_particle_diameter" should be specified to indicate that the property applies at specific particle sizes and how the size was obtained. "log10_X" means common logarithm (i.e. base 10) of X. "Aerosol" means the system of suspended liquid or solid particles in air (except cloud droplets) and their carrier gas, the air itself. "Dried_aerosol" means that the aerosol sample has been dried from the ambient state, but that the dry state (RH < 40%) has not necessarily been reached. To specify the relative humidity at which the property applies, provide a scalar coordinate variable with the standard name of "relative_humidity".
"s
> tp" means standard temperature (0 degC) and pressure (101325 Pa)."
>
> I think it is fine to propose the use of alternative coordinate variables in this way as we sometimes do with radiation_wavelength and radiation_frequency, for example. It also means that the standard name itself is more general and not tied to a specific method of measurement.
>
> You have proposed that this would be accompanied by the addition of two further coordinate variable standard names, similar to the electrical_mobility_particle_diameter that has already been accepted. I have reworded the definitions slightly.
>
> optical_particle_diameter (m)
> "The diameter of spherical particles whose presence in a medium would result in the same refractive index and lead to the same intensity of scattered light as the particles in question."
>
--> Wouldn't you then also need to specify which refractive index you are talking about and also at which wavelength you are doing the measurements ? And how do the particles "lead to" a refractive index of the medium ? As I would understand it, the medium, i.e. the air in most cases, has a refractive index which depends on the wavelength and the particles themselves also have a refractive index which depends on the wavelength in a different way than the refractive index of the air. In addition, in most cases you would assume one (representative) refractive index for the measured particles while in reality every particle has its own refractive index which depends on whether it is made of sulphate, ammonium, ice, dust, sand, sea salt and you usually will observe a mixture of more than one kind of particles.
Thanks for your clarifications !
Cheers,
Armin
--
Dr. Armin Rauthe-Sch?ch
Max Planck Institute for Chemistry
Department of Atmospheric Chemistry
Hahn-Meitner-Weg 1
D-55128 Mainz / GERMANY
Tel. +49-6131-305-4123
Fax. +49-6131-305-4009
Email: armin.rauthe-schoech at mpic.de
Received on Thu Dec 18 2014 - 09:51:13 GMT
