Total carbon variables for codetable 1-01-01.csv

[richard-olav]

Branch

https://github.com/wmo-im/wmds/blob/Issue168/tables_en/1-01-01.csv

Summary and Purpose

Add descriptions to existing variables for total and elemental carbon.

Stakeholder(s)

WG ACV

Proposal

notation	name (old)	name (new)	description (new)
623	Elemental carbon (coarse), PM10	Elemental carbon, PM10	Carbonaceous fraction of particulate matter that is thermally stable in an inert atmosphere to high temperatures near 4000K and can only be gasified by oxidation starting at temperatures above 340 degC. It is assumed to be inert and nonvolatile under atmospheric conditions and insoluble in any solvent. Size range: PM10
624	Elemental carbon, PM1	Elemental carbon, PM1	Carbonaceous fraction of particulate matter that is thermally stable in an inert atmosphere to high temperatures near 4000K and can only be gasified by oxidation starting at temperatures above 340 degC. It is assumed to be inert and nonvolatile under atmospheric conditions and insoluble in any solvent. Size range: PM1
625	Elemental carbon, PM2.5	Elemental carbon, PM2.5	Carbonaceous fraction of particulate matter that is thermally stable in an inert atmosphere to high temperatures near 4000K and can only be gasified by oxidation starting at temperatures above 340 degC. It is assumed to be inert and nonvolatile under atmospheric conditions and insoluble in any solvent. Size range: PM2.5
626	Total carbon (coarse), PM10	Total carbon, PM10	Sum of elemental and organic carbon. Includes inorganic carbon, which is operationally distributed between elemental and organic carbon. Size range: PM10

Reason

Addition of missing descriptions

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original comment
I am not able to find the representations for the variables below in the codetable 1-01-01.csv Observed variable - measurand (atmosphere):

ebas_varibale_name, cf_name,matrix
total_carbon,mass_concentration_of_total_carbon_in_pm10_minus_pm1_in_air,pm10_pm1
total_carbon,mass_concentration_of_total_carbon_in_pm10_minus_pm2p5_in_air,pm10_pm25
total_carbon,mass_concentration_of_total_carbon_in_pm2p5_in_air,pm25
total_carbon_corrected,mass_concentration_of_total_carbon_corrected_in_pm2p5_in_air,pm25
total_carbon,mass_concentration_of_total_carbon_in_dry_aerosol_particles_in _air,aerosol

Could they be added?

[IgorZahumensky]

@joergklausen can it be closed as no issue here?

[joergklausen]

Franziska: needs a Proposal and Reason, and branch with new entries along the lines of what we already have. It is clear that we will review the structure of the table more holistically, but adding new variables is more achievable right now.

[fstuerzl]

Summary and Purpose
Addition of variables for total carbon in code table 1-01-01 (Observed variable - atmosphere)

Proposal
Include the following variables in code table 1-01-01.csv

Label	Description	Path
Total carbon, PM10-PM1, in air	Mass concentration of total carbon in PM10-PM1 in air	\Atmosphere\Aerosol\Composition\Inorganic carbonaceous\Total carbon, PM10-PM1, in air
Total carbon, PM10-PM2.5, in air	Mass concentration of total carbon in PM10-PM2.5 in air	\Atmosphere\Aerosol\Composition\Inorganic carbonaceous\Total carbon, PM10-PM2.5, in air
Total carbon, PM2.5, in air	Mass concentration of total carbon in PM 2.5 in air	\Atmosphere\Aerosol\Composition\Inorganic carbonaceous\Total carbon, PM2.5, in air
Total carbon, corrected, PM2.5, in air	Mass concentration of total carbon corrected in PM2.5 in air	\Atmosphere\Aerosol\Composition\Inorganic carbonaceous\Total carbon, corrected, PM2.5, in air
Total carbon, dry aerosol, in air	Mass concentration of total carbon in dry aerosol particles in air	\Atmosphere\Aerosol\Composition\Inorganic carbonaceous\Total carbon, dry aerosol, in air

Reason
Missing entries in variable list, required by @richard-olav

[gaochen-larc]

should total carbon be organic carbonaceous or this is measurement specific?

[richard-olav]

I am not sure if this question was directed to me. But total carbon for us is related to the total of both elemental carbon and organic carbon. I believe that the "path" is misleading if "Total carbon" is specified under inorganic carbon since it usually refers to both inorganic and organic carbon.

[joergklausen]

What does 'corrected' mean?
I agree the path as proposed by @fstuerzl needs to be re-visited, and I am looking at the SAG Aerosol (@markusfiebig) to propose an improved structure for the aerosol branch of the tree.
Is it agreed that
Total carbon = Inorganic carbonaceous + Organic carbonaceous + Black carbon ?

[markusfiebig]

A few comments:

1. Total carbon is neither inorganic nor organic, thus needs to be placed at the hierarchy level above.
2. Black carbon is a qualitative term, it can't be measured, only its properties can be measured.
3. Total carbon = Inorganic carbon + Organic carbon would be true. In the respective community, they use "elemental carbon" instead of "inorganic carbon".
4. On the aerosol branch: I wrote before that the term "aerosol" is used wrongly in this hierarchy. In the hierarchy, it is referred to the aerosol particles. An aerosol denotes the whole system of particles AND the carrier gas. In the hierarchy, we should use "particle phase".
5. The variables describing the particle phase composition should be organised in an unambiguous way, which is notoriously difficult for chemical species. One of the few examples would be the IUPAC system. However, as we see with the example of "total carbon", observed properties are sometimes impossible to place in the IUPAC structure. One solution could be to have no further structure below the "composition" level. The part of the hierarchy below "Atmosphere\Particle phase\composition" seems to be overstructured.

[markusfiebig]

P.S.: The term "corrected" should probably go into a modifier in the WIGOS vocabulary, and it should state the type of correction more specifically.

[markusfiebig]

P.P.S.: One more comment concerning the structure of the "particle phase" branch. The structure distinguishes between "physical properties - primary" and "physical properties - secondary". If we distinguish that way, we would also need to do that for the optical properties, which is not the case today. However, I think we should drop that distinction alltogether. A property isn't per se primary or secondary. That depends on how the property was obtained. That type of information should not be part of the variable name, but stored in a modifier.

[gaochen-larc]

Based on "Recommendations for reporting “black carbon” measurements" by A Petzold et al.,

The recommended definition for "Total Carbon Mass" is "the mass of all carbonaceous matter in airborne particles". Traditional definition is "EC + OC", like mentioned by Markus.

Agree with Markus that BC is a qualitive variable, which represents a variety light-absorbing carbonaceous particulate (or particle) phase components.

"Total Carbon" should be under "Composition", not under inorganic or organic carbonaceous

[fstuerzl]

Updated proposal:

Label	Description	Path
Total carbon, PM10-PM1, in air	Mass concentration of total carbon in PM10-PM1 in air	\Atmosphere\Aerosol\Composition\Total carbon, PM10-PM1, in air
Total carbon, PM10-PM2.5, in air	Mass concentration of total carbon in PM10-PM2.5 in air	\Atmosphere\Aerosol\Composition\Total carbon, PM10-PM2.5, in air
Total carbon, PM2.5, in air	Mass concentration of total carbon in PM 2.5 in air	\Atmosphere\Aerosol\Composition\Total carbon, PM2.5, in air
Total carbon, corrected, PM2.5, in air	Mass concentration of total carbon corrected in PM2.5 in air	\Atmosphere\Aerosol\Composition\Total carbon, corrected, PM2.5, in air
Total carbon, dry aerosol, in air	Mass concentration of total carbon in dry aerosol particles in air	\Atmosphere\Aerosol\Composition\Total carbon, dry aerosol, in air

Other changes of the path structure, terms and modifiers depend on #173 and #181 and require further discussion.

[fstuerzl]

Branch: https://github.com/wmo-im/wmds/tree/Issue168
View differences: 24bb3ec#diff-160fbee712206a9a655a755c35b0b78b48ab1514bf8937984c6069c5fdf6ba6d
Notation to be added.

[fstuerzl]

@richard-olav, @gaochen-larc, could you confirm the branch, please?
@gaochen-larc, @markusfiebig, I think it makes sense to add the variables with the path "\Atmosphere\Aerosol\Composition" for now, if this issue should be included in the next fast track. Renaming the category "Aerosol" to "Particle phase" as discussed in #181 will take more time (milestone FT-2021-2). Do you agree?

[markusfiebig]

@fstuerzl, I'm a little confused about the proposed names. Just before Christmas, we had a telecon where we found ways to store modifiers like PM1, PM10, etc. in WMDS elements outside the variable name to prevent the list of variables from blowing up. We also agreed that the way forward would be to store these modifiers not in the variable names, but other places in the metadata record. If we now define names that include modifiers, we are locked in, or we need to change them again very soon. I would propose to leave these out.

[gaochen-larc]

Another issue we need to discuss is particle sizing technique. The particle size is very much sizing technique dependent. The air quality standard of PM2.5 is defined as aerodynamic diameter <= 2.5 um. Depending on the density of the particles, the geometric size may be significant less than 2 um.

[fstuerzl]

@gaochen-larc, the particle size will be removed from the variable names and instead we would like to include the particle size as a sampling feature. I reopened the this issue, because the variable "total carbon" itself is still missing from the code list.

path	label	description
\Atmosphere\Aerosol\Composition\Total carbon	Total carbon

Proposals for definition:

• Total carbon = Inorganic carbon + Organic carbon (traditional definition, mentioned by @markusfiebig)
• "all carbonaceous matter in airborne particles" (recommended definition, mentioned by @gaochen-larc)

[fstuerzl]

@markusfiebig, please provide consolidated proposal for terms, paths and definitions to be included (total carbon, black carbon, ...) .

[markusfiebig]

Here are my 5 cents on these definitions:

notation	name (new)	description (new)
new (?) id	elemental carbon mass concentration	Carbonaceous fraction of particulate matter that is thermally stable in an inert atmosphere to high temperatures near 4000K and can only be gasified by oxidation starting at temperatures above 340 degC. It is assumed to be inert and nonvolatile under atmospheric conditions and insoluble in any solvent.
new (?) id	organic carbon mass concentration	Mass concentration of particulate carbon contained in any of the vast number of compounds where carbon is chemically combined with hydrogen and other elements like O, S, N, P, Cl, etc.
new (?) id	total carbon mass concentration	The sum of the mass concentrations of elemental and organic carbon. Includes inorganic carbon, which is operationally distributed between elemental and organic carbon.
new (?) id	equivalent black carbon mass concentration	Carbon mass concentration obtained by conversion from particle light absorption coefficient with a suitable mass absorption coefficient.

Didn't include a definition for black carbon since we are dealing with observed properties, and black carbon cannot be observed - only properties of black carbon can be observed.

[joergklausen]

@markusfiebig Shouldn't inorganic carbon be included as a part of 'total carbon'? Cyanide, (bi)carbonate, etc?

[markusfiebig]

@markusfiebig Shouldn't inorganic carbon be included as a part of 'total carbon'? Cyanide, (bi)carbonate, etc?

@joergklausen The method used to determine elemental and organic carbon distributes inorganic carbon between the first 2 classes. I updated the definition accordingly, also updated the definition of elemental carbon.

[gaochen-larc]

The updated definition looks good to me. Thanks!

[joergklausen]

Suggestion for slight re-phrasing of description, namely drop 'assumed to be': "[...] It is inert and nonvolatile under atmospheric conditions and insoluble in any solvent." Reason: In a definition, there shouldn't be assumptions.

[markusfiebig]

There's a reason why "assumed to be" is written there. The reference methods for measuring elemental carbon cannot assure that the assumption is met.

[fstuerzl]

Consolidated proposal (as discussed in WG ACV):

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Branch

https://github.com/wmo-im/wmds/blob/Issue168/tables_en/1-01-01.csv

Summary and Purpose

Add descriptions to existing variables for total and elemental carbon.

Stakeholder(s)

WG ACV

Proposal

notation	name (old)	name (new)	description (new)
623	Elemental carbon (coarse), PM10	Elemental carbon, coarse, PM10	Carbonaceous fraction of particulate matter that is thermally stable in an inert atmosphere to high temperatures near 4000K and can only be gasified by oxidation starting at temperatures above 340 degC. It is assumed to be inert and nonvolatile under atmospheric conditions and insoluble in any solvent. Size range: coarse, PM10
624	Elemental carbon, PM1	Elemental carbon, PM1	Carbonaceous fraction of particulate matter that is thermally stable in an inert atmosphere to high temperatures near 4000K and can only be gasified by oxidation starting at temperatures above 340 degC. It is assumed to be inert and nonvolatile under atmospheric conditions and insoluble in any solvent. Size range: PM1
625	Elemental carbon, PM2.5	Elemental carbon, PM2.5	Carbonaceous fraction of particulate matter that is thermally stable in an inert atmosphere to high temperatures near 4000K and can only be gasified by oxidation starting at temperatures above 340 degC. It is assumed to be inert and nonvolatile under atmospheric conditions and insoluble in any solvent. Size range: PM2.5
626	Total carbon (coarse), PM10	Total carbon, coarse, PM10	Sum of elemental and organic carbon. Includes inorganic carbon, which is operationally distributed between elemental and organic carbon. Size range: coarse, PM10

Reason

Addition of missing descriptions

[markusfiebig]

The expressions PM10 and coarse are partly contradicting. PM10 means coarse+fine+ultrafine. For the new names, we should only use PM10, and omit coarse.

[charlesabrock]

Agreed. Chuck

On Jun 15, 2021, at 6:44 AM, markusfiebig ***@***.***> wrote: The expressions PM10 and coarse are partly contradicting. PM10 means coarse+fine+ultrafine. For the new names, we should only use PM10, and omit coarse. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#168 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ATIXPDOJSGMHIAOKCBPARBDTS5DKVANCNFSM4NJIUQUA>.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Charles Brock NOAA Chemical Sciences Laboratory 325 Broadway R/CSD2 Boulder, CO 80305 303-497-3795 (voice) 303-497-5126 (fax) ***@***.***

[fstuerzl]

Updates:

notation	name (old)	name (new)	description (new)
623	Elemental carbon (coarse), PM10	Elemental carbon, PM10	Carbonaceous fraction of particulate matter that is thermally stable in an inert atmosphere to high temperatures near 4000K and can only be gasified by oxidation starting at temperatures above 340 degC. It is assumed to be inert and nonvolatile under atmospheric conditions and insoluble in any solvent. Size range: PM10
624	Elemental carbon, PM1	Elemental carbon, PM1	Carbonaceous fraction of particulate matter that is thermally stable in an inert atmosphere to high temperatures near 4000K and can only be gasified by oxidation starting at temperatures above 340 degC. It is assumed to be inert and nonvolatile under atmospheric conditions and insoluble in any solvent. Size range: PM1
625	Elemental carbon, PM2.5	Elemental carbon, PM2.5	Carbonaceous fraction of particulate matter that is thermally stable in an inert atmosphere to high temperatures near 4000K and can only be gasified by oxidation starting at temperatures above 340 degC. It is assumed to be inert and nonvolatile under atmospheric conditions and insoluble in any solvent. Size range: PM2.5
626	Total carbon (coarse), PM10	Total carbon, PM10	Sum of elemental and organic carbon. Includes inorganic carbon, which is operationally distributed between elemental and organic carbon. Size range: PM10