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WIGOS Metadata Standard: Semantic standard and code tables
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1-01-01 Definition of present and past weather variables #364

Closed meulenvd closed 2 years ago

meulenvd commented 2 years ago

Issue Summary

Purpose

Definitions are missing for http://codes.wmo.int/wmdr/ObservedVariableAtmosphere/265 http://codes.wmo.int/wmdr/ObservedVariableAtmosphere/266

Stakeholder(s)

n/a

Proposal

Add definition for the specific weather phenomena and present weather variables, as defined in WMO-No. 306. Considering UDC as well.

notation name description tags
265 Past weather Predominant characteristic of weather which had existed at the station during a given period of time [source: Manual on Codes,Volume I.1 (WMO-No. 306)] atmosphere
266 Present weather Weather existing at the time of observation, or under certain conditions, during the hour preceding the time of observation [source: Manual on Codes,Volume I.1 (WMO-No. 306)] atmosphere

Reason

All entries in https://codes.wmo.int/wmdr should have definitions/descriptions/tags.

Consultations

@gaochen-larc @meulenvd @ferrighi

Context

Definitions from different sources were considered:

Ultimately, the task team agreed on adopting the definitions in WMO-No. 306, Vol. I.1 Manual on Codes.

amilan17 commented 2 years ago

https://library.wmo.int/doc_num.php?explnum_id=3160 https://library.wmo.int/doc_num.php?explnum_id=10616

joergklausen commented 2 years ago

@fstuerzl Please create branch @meulenvd Please review branch @gaochen-larc, @ferrighi Please confirm

fstuerzl commented 2 years ago

New definitions added in branch: https://github.com/wmo-im/wmds/commit/f9233cf2d006bdbe095ca4dad30a22bc97f5aafa

gaochen-larc commented 2 years ago

I confirm that the proposed names and descriptions are appropriate.

joergklausen commented 2 years ago

I confirm this branch is correct.

joergklausen commented 2 years ago

@meulenvd Your confirmation would be valuable.

meulenvd commented 2 years ago

The proposal from WMO-No. 8 can be used, but 265 is on weather events and 266 on weather phenomena, which may confuse. In practice it focusses on "weather", not typically events of phenomena (like defined in the WMO International Cloud Atlas, Annex to the Techn. Reg-s, WMO-No. 407)

May be better and officially endorsed sources are:

[1] WMO-No. 182, INTERNATIONAL METEOROLOGICAL VOCABULARY P1530 present weather: Weather existing at a station at the time of observation; P0180 past weather: Predominant characteristic of the weather which had existed at an observing station during a given period of time, specified in the international SYNOP code.

[2] WMO-No. 306, Vol. I.1 Manual on Codes, PART A – Alphanumeric Codes Present weather: Weather existing at the time of observation, or under certain conditions, during the hour preceding the time of observation. Past weather: Predominant characteristic of weather which had existed at the station during a given period of time

gaochen-larc commented 2 years ago

I do not have any issues with what @meulenvd proposed.

I like "characteristic of weather". The definition of "weather" can be broad: https://glossary.ametsoc.org/wiki/Weather, especially to those who are not in the field. I think we should be consistent with WMO definition, but there are apparently some differences between different documents.

amilan17 commented 2 years ago

I think it will be better to use the WMO-No. 182 definitions. 

Also, I think it's a best practice to NOT include URLs in the definitions.

joergklausen commented 2 years ago

@meulenvd To me, No. 8 is equally normative, but if you prefer to refer to WMO-No. 306, Vol. I.1, I don't have a problem with that. I do have a problem with the reference to SYNOP in the definition in WMO. 182, though, because we cannot define a term with reference to another term that is not defined. Please update the branch and the first comment in the issue, then ask us for confirmation. We should conclude this ASAP.

meulenvd commented 2 years ago

Yes the reference to SYNOP in WMO-No. 182 is a bit strange, but understandable. This is because reporting weather phenomena where requested already during the IMO area and therefore is present and past weather always associated to data exchange (and therefore defined in the Manual on Codes).

Other examples I found are:

WMO-No. 544 Manual on the GOS (obsolete; definition modified when transferring it into the Manual on the WIGOS) Weather: State of the atmosphere at a particular time, as defined by the various meteorological elements. – Present weather: Weather existing at a station at a time of observation. – Past weather: Predominant characteristic of the weather which existed at an observing station during a given period of time.

WMO-No, 1160 (2021) Manual on the WIGOS: Present and past weather: The qualitative description of observable phenomena, at the time of observation or during a preceding period. Note: Relevant observable phenomena in the atmosphere include precipitation, suspended or blowing particles, and other designated optical phenomena or electrical manifestations, as described in the International Cloud Atlas – Manual on the Observation of Clouds and other Meteors (WMO-No. 407), the Guide to Instruments and Methods of Observation (WMO-No. 8) and, for aeronautical applications, in the Technical Regulations (WMO-No. 49), Volume II.

So I think the definition given in the Manual on the WIGOS is the most actual version (present and past weather given by one definition) and has preference. In fact it combines the defition of the ols Man. GOS into one.

amilan17 commented 2 years ago

I vote for the definitions in MoC

[2] WMO-No. 306, Vol. I.1 Manual on Codes, PART A – Alphanumeric Codes
Present weather: Weather existing at the time of observation, or under certain conditions, during the hour preceding the time of observation.
Past weather: Predominant characteristic of weather which had existed at the station during a given period of time

joergklausen commented 2 years ago

In support of @amilan17 .

amilan17 commented 2 years ago

I updated the new branch with the definitions from MoC, but I have not updated the issue summary yet.

ferrighi commented 2 years ago

WMO-No. 306 seems the best set of definitions.

fstuerzl commented 2 years ago

@amilan17, I've included the definitions from MoC in the proposal above.

gaochen-larc commented 2 years ago

In support of @amilan17 .

I second

meulenvd commented 2 years ago

The best choice for Present and Past Weather is a bit a dillemma for me. The definition in the WMO-No. 360, Manual on Codes (Vol I) is exactly the same as in WMO-No. 544 Manual on the GOS (now obsolete). When transferring the Manual on the GOS into WMO-no. 1160, the Manual in the WIGOS it was decided by the EdBd to update the definition into a more generic form (see my comment above; Present and past weather: The qualitative description of observable phenomena, at the time of observation or during a preceding period.). The term Present and Past Weather has a long history (> 70 a) and everything to do with reporting (e.g. FM12 - Synop). Because of it limitations (short bulletins send over telex or telegraph) and reporing frequency (e.g. only at the main hours) it was necesary to report a simple code (well known as de WW code). This code should contain the most significant weather at the station during the observation interval, but because of the long reporting interval also significant weather (e.g.a thunderstorm 2 hours ago) should be reported (as past weather). For each WW (00-99) there is a specific symbol designed, to be used in the synoptic weather maps. Relevant is that present & past weather belong to the subset of "subjective observations". These are observations that cannot be reported as "objective", quantitative variables like e.g. temperature (therefore: qualitative descriptions). Note that today most of the items in WW (or WaWa for AWS) can be reported quantitatively (precipitation intensity, lightning, obstruction to vision) and it is recommended to do so only. This is the major reason why the definition was modified when transferring the Man GOS into Man WIGOS.

amilan17 commented 2 years ago

If it helps, a quick search in OSCAR/Surface results in 8448 stations / platforms found with these codes.

amilan17 commented 2 years ago

https://github.com/wmo-im/wmds/wiki/2022-05-19-TT-WIGOSMD-22 notes:

joergklausen commented 2 years ago

Proposal approved by team, summary will be amended to reflect sources considered.

fstuerzl commented 2 years ago

I've included the context in the proposal summary, citing the various definitions and sources that were mentioned.

amilan17 commented 2 years ago

@joergklausen - ready to validate

amilan17 commented 2 years ago

https://github.com/wmo-im/wmds/wiki/2022-05-31-TT-WIGOSMD-23 notes: @joergklausen validate

amilan17 commented 2 years ago

@meulenvd -- this link (https://library.wmo.int/doc_num.php?explnum_id=3160) takes the user to a copy of a chapter of a publication. Do you know which WMO Publication it came from?

joergklausen commented 2 years ago

https://library.wmo.int/doc_num.php?explnum_id=10616

meulenvd commented 2 years ago

@amilan17 - the link (https://library.wmo.int/doc_num.php?explnum_id=3160) refers to Chapter 14 of WMO-No. 8, Vol I. (GIMO, WMO Guide to Instruments and Methods of Observation). A better is link to WMO-No. 8 (2018 ed.) is (https://library.wmo.int/index.php?lvl=notice_display&id=12407) for all 5 Volumes, or (https://library.wmo.int/doc_num.php?explnum_id=10616) for the download of the Vol I pdf. ( @joergklausen - for info: the Man on the GOS (WMO-No. 544) is obsolete but largerly merged into the Man on the WIGOS (WMO-No. 1160))

amilan17 commented 2 years ago

ready for FT