Difference between revisions of "CF Standard Names - Construction of Atmospheric Chemistry and Aerosol Terms"

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*chemical species and aerosols: describe the species
 
*chemical species and aerosols: describe the species
 
*generic names: describe the property of the species, and determinethe unit of the variable
 
*generic names: describe the property of the species, and determinethe unit of the variable
*processes: are used in flux variables: tendency_of_.... due_to_<process&gt and give the change of the species' property du to a certain process
+
*processes: are used in flux variables: tendency_of_.... due_to_<process> and give the change of the species' property du to a certain process
 
*medium: indicates the local medium or layer within which the variable applies
 
*medium: indicates the local medium or layer within which the variable applies
  

Revision as of 06:07, October 29, 2008

Return to Start page for Atmospheric Chemistry and Aerosol Names PLEASE DO NOT USE THE NAVIGATION BAR ON THE LEFT HAND SIDE!



This page provides the basis for the construction of CF standard names for atmospheric chemistry and aerosols.

The concepts described here have been developped since May 2006 for the definition of the 207 standard names that are accepted by the CF community as of october 2008.

The construction of CF standard names for aerosols and chemicals originated in the work of the PRISM project (Peter van Velthoven) see PRISM Standard Name Tables, latest Version, V 1.3. They have then been further developped on this wiki page and within the CF-mailing list. Important contributions come from the participating model intercomparison projects listed on the entry page.

The CF web site provides general Guidelines for Construction of CF Standard Names. The CF standard names for aerosols and chemicals are composed by the addition of phrases in certain standard forms and order following these guidelines. The concept is explained below in section 2.

At the moment, many new proposals for standard names for aerosols and chemicals are under discussion at the CF mailing list. Therefore, I try to summarize the current status of work here, in order to highlight the principles and concepts we have devolopped so far.

A large quantity of new standard names for chemical species might be necessary in the future. This requires the development of a general approach on how to proceed. Four main ideas are discussed at the moment:

  1. Definition of each chemically related standard name explicitly in the CF standard name list, and discuss each of these names individually (current approach).
  2. Definition of groups of standard names (see below) with the individual chemical species or aerosol type given as a scalar coordinate. Names for individual species would not appear any more as CF standard names. Unphysical names would not occur, but the names would not be as human-understandable any more.
  3. Definition of groups of standard names (see below). Creation of all possible names from these for new individual chemical species or aerosols using a script, even if some of them might not have a physical meaning.
  4. Definition of groups of standard names (see below). Creation of all possible names from these for new individual chemical species or aerosols using a script. Experts review these possible names and eliminate unphysical before submission to the CF community.

The descriptions below could help to converge to the most efficient strategy.




LIST OF ACCEPTED STANDARD NAMES FOR AEROSOLS AND CHEMICALS

The list of standard names for aerosol ad chemicals accepted by October 29 2008 can be found here.

CONSTRUCTION OF STANDARD NAMES FOR AEROSOLS AND CHEMICALS

Certain phrases and forms ure used:

  • chemical species and aerosols: describe the species
  • generic names: describe the property of the species, and determinethe unit of the variable
  • processes: are used in flux variables: tendency_of_.... due_to_<process> and give the change of the species' property du to a certain process
  • medium: indicates the local medium or layer within which the variable applies

The combination of these phrases and names results in groups of Standard_Names that are given below. However, not all combinations are possible or reasonable. There are some odd names that do not fit in the general concepts. Modifications are suggested for these names in order to allow for the automatic creation of individual names from groups of CF standard names.

Phrases and forms

Chemical species and aerosols

These can be chemical species with a defined molar mass (molecules, salts, etc.) or components that do not have a defined molar mass (aerosol, biological species)
Goto to the list of chemical species and aerosols as of 29 October 2008.

Generic Names

angstrom_exponent [1]
optical_thickness [1]
mass_content [kg/m2]
mass_fraction [kg/kg]
mass_concentration [kg/m3]
mole_concentration [mole/m3]
mole_fraction [mole/mole]
moles [moles]

tendency_of_<Z>_<X>_due_to_<process> <Z=mass_content or moles> [unit of Z/s]

Processes

dry_deposition
dry_emission
dry_re_emission
wet_deposition
net_production_and_emission
dry_deposition_into_stomata

<no process=total changes>

Medium

in_air
in_sea_water
in_atmosphere
in_middle_atmosphere
in_troposphere

or atmosphere used as a prefix (suggested to be changed)

Groups of Standard_Names for chemicals and aerosols

The combination of the prases and forms given above results in groups of Standard_Names for chemicals and aerosols:

atmosphere_optical_thickness_due_to_<A_ambient_aerosol>
atmosphere_optical_thickness_due_to_<A_aerosol>
mass_fraction_of_<A_dry_aerosol>_in_air
mass_fraction_of_<A_wet_aerosol>_in_air
mass_fraction_of_<A_aerosol>_in_air
mass_concentration_of_<A_aerosol>_in_air
mole_concentration_of_<X>_in_sea_water
mole_fraction_of_<G>_in_air
moles_of_<G>_in_atmosphere
tendency_of_atmosphere_mass_content_of_<X>_due_to_dry_deposition
tendency_of_atmosphere_mass_content_of_<X>_due_to_dry_emission
tendency_of_atmosphere_mass_content_of_<X>_due_to_dry_re_emission
tendency_of_atmosphere_mass_content_of_<X>_due_to_wet_deposition
tendency_of_atmosphere_mass_content_of_<X>_due_to_net_production_and_emission
tendency_of_atmosphere_mass_content_of_<X>_due_to_dry_deposition_into_stomata
tendency_of_atmosphere_mass_content_of_<X>_due_to_wet_deposition
tendency_of_atmosphere_mass_content_of_<X>_due_to_wet_deposition
tendency_of_moles_of_<G>_in_atmosphere
tendency_of_moles_of_<G>_in_middle_atmosphere
tendency_of_moles_of_<G>_in_troposphere

Odd names that do not fit in any group following the general concepts

atmosphere_content_of_sulfate_aerosol
optical_thickness_of_atmosphere_layer_due_to_aerosol?
mass_concentration_of_sulfate_aerosol_in_air
surface_carbon_dioxide_mole_flux

We suggest changes to modify these names, so that they would fit in the general concepts explained here and allow for the automatic creation of individual names from groups of CF standard names.