TT AvData Teleconference 2021 April 30 and 2021 May 3

Details

2021-April-30, 9:00-10:00 UTC, Microsoft Teams and 2021-May-3, 10:00-11:00 UTC, Microsoft Teams

Agenda (draft)

1. Review previous actions
2. IWXXM 2021-2-dev draft
3. Schedule next meeting
4. AOB

Minutes (predicted)

Review previous actions

• DONE - Anna: help organize GitHub issues alignment with FT branches
• DONE - Anna: follow up on email options for public consultation
• IN PROGRESS - ALL: Choose a branch to validate, self assign in issues and capture notes in issues.
• IN PROGRESS - Jan, Choy and interested: To finalize the issues involving WC and WV SIGMET within this week
• IN PROGRESS - Choy: To finalize changes with regard to the code lists and prepare the corresponding RDF files for evaluation

IWXXM 2021-2-dev draft

• Confirm the distribution is fit-for-public consultation and identify outstanding items (https://github.com/wmo-im/iwxxm/labels/publicConsultation)
  • Individual package
    • METAR/SPECI: OK with resolvable outstanding item
      • Outstanding item: Improve descriptions in iwxxm:runwayState
    • TAF: OK with resolvable outstanding item
      • Outstanding item: Re-version as 3.0.1
    • SIGMET: Not OK
      • Changes to schemas and examples to fix #209: Participants were of the view that while Note 19 did mention "Each location and forecast position is to be preceded by an observed or forecast time", it was not until the publication of examples in the ICAO APAC SIGMET guide that we realized the first observation time could be different for tropical cyclone position + first CB cloud and the second CB cloud. This was beyond the normal understanding of providing "snapshots" in messages and will affect the information model of IWXXM SIGMET. In the worst case we may need to separate WS, WA and WC SIGMETs into 3 different information models instead of sharing a single core part. The team agreed that we shall mark it as a known issue and bring our concern back to the respective ICAO team (which should be WG-MOG) for their attention. See also Notes 1-3 at the end for additional information on our views with regard to information requirements.
      • Committed changes in the branch and outstanding changes on improving descriptions on tropical cyclone movement will not be implemented as they are related to the changes for #209.
    • AIRMET: OK
    • TCA: OK with a resolvable optional item
      • Outstanding items: Improve descriptions in iwxxm:TropicalCycloneIntensityChange
    • VAA: OK
    • SWA: OK
    • WAFS SIGWX Forecast: OK with resolvable outstanding items
      • Outstanding items: Implement changes with regard to the use of certain code lists; implement code list checking schematron rules for codelist class; confirm with WAFCs on the examples and whether they will be included in the distribution.
  • Cross package; Not OK
    • Changes to add extension to code list and enumeration: While participants had general consensus on how this could be achieved technically, WMO Secretariat had reservation as the change would induce a change in existing schemas which should be considered as a breaking change, even though the instances involved should be exactly the same before and after the change. A separate discussion would be raised to agree how to deal with such changes.
  • Code lists: OK with resolvable outstanding items
    • Outstanding items: Tidy up RDF files incorporating the changes in CSV and also those involving WAFS SIGWX Forecast.
• Prepare and publish IWXXM 2021-2RC1: Choy would populate the branches with the agreed changes and also create a new branch 2021-2RC1 to host the final version for merging into the master branch and publication on schemas.wmo.int.
• Announce commencement of public consultation
  • Anna would help in preparing the e-mail announcement which could be based on previous ones in the Google group.

Decisions and Actions

• Choy: To finalize the changes and prepare the 2021-2RC1 branch for final checking and publication.
• Anna: To prepare an e-mail to announce the public consultation.

AOB

• Choy: The team may need to bring to the attention of WG-MIE during its teleconference on 11 May 2021 the team's decision on changes to be implemented in FT2021-2. As Greg is expected to join the discussion too it would be nice if the secretariat could give him a hint beforehand.
• Choy: Indicated that the team may need to have its own version of workflow diagram to showcase we have well defined working arrangements and procedures.

Attendees

• BL Choy
• Mark Oberfield
• Dirk Zinkhan
• Anna Milan
• Xiaoxia Chen
• Enrico Fucile
• Ján Körösi
• Dmitry Moryakov
• Yann Génin
• Stephanie Wigniolle

Apologies

• Dmitry Moryakov (3 May 2021)

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Note 1: In 2016 METP/2 had formulate the following recommendation:

Recommendation 8/1 — Traditional Alphanumeric Code (TAC): That the proposal by the Panel that no further changes to the traditional alphanumeric code (TAC) form for meteorological messages be allowed unless a strong safety case is presented and agreed be endorsed by the Air Navigation Commission.

Note 2: The following ideas were discussed during MIE/5 in 2019 for the WMO team to have early consideration of Annex changes that will likely impact IWXXM schema, thereby allowing WMO to provide their feedback on the perceived impact of proposed changes:

• Raise the possibility of changes to Annex 3 that requires an update to IWXXM as early as possible.
• Invite the WMO TT-AvXML, as early as possible, to review the possible impact to IWXXM and advise the expected available time for the revised schemas, considering the frequency of IWXXM releases with breaking changes and complexity of the changes.
• Encourage the TT-AvXML to file possible/expected/confirmed changes to IWXXM in a roadmap, in consultation with those who requested the changes and communicate electronically (i.e.via the web)to inform stakeholders.
• Prepare draft changes to IWXXM in association with the proposed changes to Annex 3 for consideration by ICAO WGs, METP and the Air Navigation Commission (ANC), especially after the cessation of TAC.

Note 3: SN/3108 was brought up in MIE/7 in 2021 to raise the awareness on difficulties TT-AvData was facing when they attempted to develop the IWXXM information model based on inadequate description of requirements in Annex 3.