wmo-im/wmds

Table 5-02-01: new methods of observation (for atmospheric variables)

Closed this issue · 27 comments

Initial request

I think root items of the “add measurement program" tree and “methods” tree should be exactly the same. Because it is mandatory to defines the method of observation for any measurement program. My suggestion for the mentioned variables is as follows:

- Sunshine duration

  • Campbell-Stokes sunshine recorder (burn method)
  • Pyrheliometric method
  • Pyranometric method
  • Contrast-evaluating and scanning devices 

- Visibility

  • Human observation
  • Scatterometer
  • Transmissometer

- Present weather

  • Human observation
  • Automated observation

- Past weather

  • Human observation
  • Automated observation

Requestor(s)

NFP-OSCAR/Surface from Iran (hesam.sajdeh@gmail.com)
and Alexander Scheid (AScheid@wmo.int)

Amendment details

updated 30 June 2023

Add:

notation path name description
tbd /Atmosphere/Radiation/In-Situ/ Campbell-Stokes burn method Sunshine duration is determined by evaluating the burnt areas imprinted by the sun in a strip of carton or aluminum foil placed behind a glass sphere.
tbd /Atmosphere/Radiation/In-Situ/ Contrast-evaluating and scanning devices Sunshine duration is determined by combining multi-sensor detectors with electronic discriminator.

Deprecate:

notation path name description reason
198 /Atmosphere/Radiation/in-situ/ sunshine duration missing term refers to an observed quantity/variable, not a method, and is therefore useless

Comments

Stakeholder(s)

Publication(s)

Expected impact of change

MEDIUM-HIGH

Collaborators

References

Validation

Branch

https://github.com/wmo-im/wmds/tree/issue336

@amilan17 I can't assign myself apparently, but here's my username.

We need a branch with a concrete proposal. In principle, I support adding these methods now, even though there are significant changes to the methods code lists on the horizon for WMDR2.0 (separation of domain from method, therefore need for removal of resulting duplicates, e.g. Human observation).

@amilan17 - create branch

@anthoninlize @MKrieger29 -- have you had a chance to work on this issue? If we want this to be submitted in FT22-2, then the proposal should be ready before the end of the month.

The original proposal cannot be supported as is. It listed observed variables or groupings of observed variables, and then mostly instruments:

  • Visibility
    • Human observation
    • Scatterometer
    • Transmissometer
  • Present weather
    • Human observation
    • Automated observation*
  • Past weather
    • Human observation
    • Automated observation*

* Recognizable phenomena should be specified

I had commented previously that several of the proposed elements already exist, albeit under specific paths. In terms of the WIGOS code registry, these paths do not even exist, so they are not relevant for the specification of a method. In future, also this code table needs to be re-worked, making use of tags instead of paths.

I have updated the proposal, indicating in bold what I see is still missing. @anthoninlize @MKrieger29 Please review and reach out to stakeholders outside WMO/OceanOPS. Such stakeholders must also be listed explicitly, so that we can contact and refer to them.

moving target milestone to FT2023-1

https://github.com/wmo-im/tt-wigosmd/wiki/2022.10.20-TT-WIGOSMD notes:

@RMaerz will reach out to colleagues and update the issue summary before next meeting

@amilan17 update issue summary to match new style

@RMaerz @joergklausen I'm going to email the originator of this request to inform him of the status of this issue. Can you confirm that the summary above is correct? (in this comment)

I mostly agree but 'human observation' does not exist for visual range , only for clouds as far as I found. So it needs to be added like
[ tbd , 'Atmosphere/Visual Range/human observation' , determining visibility with help of objects in known distance from observing site ]

https://github.com/wmo-im/tt-wigosmd/wiki/2022.11.03-TT-WISOSMD notes:

  • @RMaerz: don't add "contrast-evaluating and scanning devices" till we have more information. 'human observation' is currently limited by the path
  • @meulenvd: recommends looking at WMO-No. 8 for sunshine variables
  • @amilan17: email requestor and cc' @RMaerz
  • @RMaerz: add definitions in the issue summary under 'amendment details'

https://github.com/wmo-im/tt-wigosmd/wiki/2022.11.22-TT-WIGOSMD notes:

(@RMaerz) reviewed CIMO guide and updated Amendment Details and will add reference to the guide and new definitions.

(@joergklausen) please try to finalize proposal before next meeting

https://github.com/wmo-im/tt-wigosmd/wiki/2022.12.08-TT-WIGOSMD notes:
@RMaerz updated issue summary, will add reference to WMO-No. 8 when used, but not sure how to add definition for human observations for clouds. @gaochen-larc suggests finding a definition for how it used to be done from the Itl' Cloud Atlas. @JohnEyre said it may be more about how the clouds are observed by humans.

https://github.com/wmo-im/tt-wigosmd/wiki/2023.02.16-TT-WIGOSMD notes:

Rainer will be ready to talk about at the next meeting

@RMaerz Please provide a description of 'human observation' (of clouds) in the description before the meeting on 2023-03-17.

notation 24: human observation = "Determination of type and coverage of clouds by a trained human observer following prescribed procedures."

https://github.com/wmo-im/tt-wigosmd/wiki/2023.04.06-TT-WIGOSMD notes:
(Jitze) usually don't talk about quantity of clouds (Joerg) changed to coverage; (Anna) add clouds into the name? (Gao) double check with cloud atlas?
https://cloudatlas.wmo.int/en/observation-of-clouds-from-the-earths-surface.html (Anna) there is already a generic definition: http://codes.wmo.int/wmdr/SourceOfObservation/humanObservation; (Jitze) 'visual observation' is often used.
(Jitze) there is training material on how to observe.

24 | Human observation | Observation of clouds from the Earth's surface by a human observer (ref: https://cloudatlas.wmo.int/en/observation-of-clouds-from-the-earths-surface.html)

https://github.com/wmo-im/tt-wigosmd/wiki/2023.04.21-TT-WIGOSMD notes:
team agrees to updated description of 'human observation'.

Branch updated, ready for validation; needs pull request.

Notation 170 and 209 should have comparable descriptions because the technology is based on comparable optical behavior:
To be:

  • 170 (Scatterometer): Visual range is calculated from the Meteorological Optical Range (MOR or visibility) or extinction coefficient by measuring the amount of light scattered by aerosols and other particles when passing a specific volume of air, using a single light source.

  • 209 (transmissometer): Visual range is calculated from the Meteorological Optical Range (MOR or visibility) or extinction coefficient by measuring the amount of light of a light beam that remains due to scattering and absorption by aerosols and other particles when passing a specific volume of air, using a single light source.

I believe @meulenvd may have mixed up the notations: 190 (instead of 170), 207 (instead of 209).
More importantly, "by aerosols and other particles" is not an ideal wording. "Aerosol" is a combination of gas and particles, so 'other particles' is not necessary. Moreover, I am not convinced the adding more words here has provided more clarity, because scattering and extintion and absorption are now all convoluted. I am not very familiar with this kind of instruments, but a measurement of the scattering is different than a measurement of the extinction.

https://github.com/wmo-im/tt-wigosmd/wiki/2023.06.15-TT-WIGOSMD notes:

Team reviewed latest comments; @amilan17 verify that Scatterometer is not used in another 5-02* table; there was a discussion about including 'air' in the definition and how it relates to the path; 

DECISION move the 3 new variables into a new issue in order to align with a better path approach; 

@amilan17 create new issue and update branch

I recommend setting status of  "sunshine duration" to Retired or superseded it by new code for the method?

created new issue #499

https://github.com/wmo-im/tt-wigosmd/wiki/2023.06.30-TT-WIGOSMD notes:

valid, small update to text of "contrasting-evaluating and scanning..."