Dear Alison,
great overview! Thanks very much for this. I am happy with all of your suggestions, so you can count my vote if needed.
Concerning the "resistance" terminology: This refers to a resistance model approach for which a paper by Wesely, 1989 (Atmos. Env., 23/6) is widely referred to. This paper talks about "surface resistances" and explicitly mentions "aerodynamic resistance", "quasilaminar sublayer resistance", and "bulk surface resistance", the latter being composed of various terms, among them a term for "stomatal resistance". Explicit reference is made to Ohm's law as analogy, and this concept is widely known in the community. I would hence argue in favour of keeping the word resistance in these terms.
With best regards,
Martin
Message: 2
Date: Fri, 21 Nov 2014 12:18:34 +0000
From: <alison.pamment at stfc.ac.uk>
To: <cf-metadata at cgd.ucar.edu>
Cc: frank.dentener at jrc.ec.europa.eu, michael.schulz at lsce.ipsl.fr
Subject: Re: [CF-metadata] HTAP2 last revisions
Message-ID:
<014539AC4976BE4490A360410A8C2017792A828C at EXCHMBX03.fed.cclrc.ac.uk>
Content-Type: text/plain; charset="us-ascii"
Dear Brigitte, Markus and Martin,
I have reviewed the discussion of all the HTAP names proposed by Brigitte at the beginning of this year. This is in preparation for making an update to the standard name table. I am also in the process of reviewing Markus Fiebig's own proposals (see
http://mailman.cgd.ucar.edu/pipermail/cf-metadata/2013/056946.html and follow up posts) as the discussions of the two sets of names overlap. I will post later today about Markus' names.
[...]
Two new proposals were added at the end of the discussion: (see
http://mailman.cgd.ucar.edu/pipermail/cf-metadata/2014/057372.html).
canopy_resistance_to_ozone_dry_deposition (m-1 s) " The "canopy_resistance" is the resistance of a compound to uptake by the vegetation canopy. It varies both with the surface and the chemical species or physical state (gas or particle)."
aerodynamic_resistance (m-1 s)
"The "aerodynamic_resistance" is the resistance to mixing through the boundary layer toward the surface by means of the dominant process, turbulent transport."
I am not very familiar with either of these quantities and no comments have been received on these proposals. A quick internet search suggests that both terms are in wide use in the literature.
My (brief) research revealed that aerodynamic_resistance is sometimes termed "aerodynamic drag" which is more similar to existing standard names for heat, momentum and gravity wave drag. Perhaps "aerodynamic_drag" would therefore be more appropriate for this name? (I don't have a strong opinion either way). If it is a resistance to downward turbulent transport, then presumably that refers to transport of aerosol particles? Perhaps we should also put that in the name to make it more self explanatory, e.g., aerodynamic_drag_on_turbulent_deposition_of_aerosol_particles or resistance_to_turbulent_deposition_of_aerosol_particles_due_to_aerodynamic_drag. These are just suggestions and I'd welcome other opinions. Regarding the definition, it appears that there are a number of different formulae for this quantity (see for example the first paragraph of
http://agsys.cra-cin.it/tools/evapotranspiration/help/Aerodynamic_resistance.html). Does this proposal relate to any particular formulation? If so, we should provide
a reference in the definition.
Regarding the canopy resistance name, could it be reworded to canopy_resistance_to_downward_flux_of_ozone_due_to_dry_deposition? Perhaps this more clearly relates the quantity to other atmospheric names? I don't know if that is useful and again it is just a suggestion. Also, if there is a particular formula or reference for this quantity we should include it in the definition.
That concludes my somewhat lengthy comments! If we can agree any of the "under discussion" names over the next two or three working days then they can also be accepted in time for inclusion in the upcoming standard name table update.
Best wishes,
Alison
------
Alison Pamment Tel: +44 1235 778065
NCAS/British Atmospheric Data Centre Email: alison.pamment at stfc.ac.uk
STFC Rutherford Appleton Laboratory
R25, 2.22
Harwell Oxford, Didcot, OX11 0QX, U.K.
------------------------------------------------------------------------------------------------
------------------------------------------------------------------------------------------------
Forschungszentrum Juelich GmbH
52425 Juelich
Sitz der Gesellschaft: Juelich
Eingetragen im Handelsregister des Amtsgerichts Dueren Nr. HR B 3498
Vorsitzender des Aufsichtsrats: MinDir Dr. Karl Eugen Huthmacher
Geschaeftsfuehrung: Prof. Dr.-Ing. Wolfgang Marquardt (Vorsitzender),
Karsten Beneke (stellv. Vorsitzender), Prof. Dr.-Ing. Harald Bolt,
Prof. Dr. Sebastian M. Schmidt
------------------------------------------------------------------------------------------------
------------------------------------------------------------------------------------------------
Received on Mon Nov 24 2014 - 14:05:52 GMT
