blchoy
commented
3 years ago Closed as this will be followed up in https://github.com/wmo-im/iwxxm-codelists/issues/9
Closed blchoy closed 3 years ago
blchoy
commented
3 years ago Closed as this will be followed up in https://github.com/wmo-im/iwxxm-codelists/issues/9
IWXXM is probably the first WMO code format using WMO Codes Registry URIs in referencing published code list entries in its instances. While these URIs (e.g.
http://codes.wmo.int/49-2/AirWxPhenomena/BKN_CLD) may hint that the codes related to aviation (e.g. WMO No.49 Vol. II), there are mostly aliases to published code tables for BUFR and other code formats. The following are IWXXM code lists on WMO Codes Registry being referenced by IWXXM and associated published WMO code tables:49-2:
bufr4/codeflag:
common:
There is a historic reason for IWXXM to make reference to BUFR code tables: BUFR sequences and associated code tables for METAR/SPECI and TAF were created in a previous attempt to migrate from TAC but that had been abandoned after the aviation community made a decision to move from TAC to XML/GML instead. In the early stage of development of IWXXM, references was made to these code tables directly as they were published but that was quickly been replaced by IWXXM specific WMO Codes Registry URIs which are aliases to the BUFR tables. During further development of IWXXM, more URIs were created which relied solely on the registry for publication.
In a recent (6 Nov 2020) WMO ET-Data discussion, a number of ideas were raised to improve the situation which include (i) making IWXXM code tables independent from where they were inherited, (ii) properly maintain these code tables under WMO No.306 Vol. I.3, (iii) discuss with other teams the way forward with common code tables as the requirements from involving domains evolve. There may still be indication of relationships between entries of a code table with another but that will depend whether there is a need to do so and whether the WMO Codes Registry supports this functionality.
This issue intends to raise the awareness of others and upon confirmation of TT-AvData track relevant activities to be made. As new code tables will have to be created to support WAFS SIGWX forecasts, it is anticipated that changes (if decided) will be made with the publication of IWXXM 3.2 in late 2021 or mid-2022.
There is a separate GitHub repository for IWXXM code lists on WMO Codes Registry: https://github.com/wmo-im/IWXXMCodeLists.