Station concordance with international identifier systems

[gutzbenj]

Is your feature request related to a problem? Please describe.
Coming from discussions at #70 (comment) and #209 (comment), we want to allow for definition of stations by possible other ids that may be allocated to them like for e.g. WMO identifier or others.

Describe the solution you'd like
WMO station identifiers can be taken from OSCAR. There is also pyoscar, which provides a Pythonic API atop the HTTP API of WMO's OSCAR/Surface, which is the World Meteorological Organization's official repository of WIGOS metadata for all surface-based observing stations and platforms.

However, there is no clear relation to the domestic DWD station identifier, so we will have to setup an individual matching system between the domestic identifier and the wmo identifier.

Describe alternatives you've considered
Eventual stations could be matched by location, however that takes a lot of computation and should rather be done once and stored as JSON.

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Example

Let's use Berlin-Dahlem as an example. Its WIGOS Station Identifier is 10381 [1]. Its domestic station identifier is 00403 [2].

[1] https://oscar.wmo.int/surface/#/search/station/stationReportDetails/0-20000-0-10381
[2] https://opendata.dwd.de/climate_environment/CDC/help/wetter_tageswerte_Beschreibung_Stationen.txt

[amotl]

Quickly scanning the open data server of @DeutscherWetterdienst, the resources at [1] or [2] include WMO identifiers, however resources like [3] or [4] only include the domestic identifiers of DWD.

[1] https://opendata.dwd.de/weather/local_forecasts/mos/MOSMIX_L/single_stations/
[2] https://www.dwd.de/DE/leistungen/met_verfahren_mosmix/mosmix_stationskatalog.cfg?view=nasPublication
[3] https://opendata.dwd.de/climate_environment/CDC/help/VV_Stundenwerte_Beschreibung_Stationen.txt
[4] https://opendata.dwd.de/climate_environment/CDC/help/wetter_tageswerte_Beschreibung_Stationen.txt

[amotl]

Resources about the WMO Integrated Global Observing System (WIGOS) can be found at [1], specifically about the WIGOS Station Identifier (WSI) can be found at [2].

At [3] and within [4], we found references to the WMO Country Profile Database (CPDB).

[1] https://www.wmo.int/pages/prog/www/wigos/
[2] https://www.wmo.int/pages/prog/www/wigos/WSI.html
[3] https://www.wmo.int/pages/prog/www/wigos/wigos-readiness.html
[4] http://www.wmo.int/pages/prog/www/wigos/documents/Tools/Annex-to-Decision-31_EC-69.docx

[amotl]

On the CPDB page, there is an information box which says:

03 June 2020: With the release of version 3 of the CPDB, the country profiles have been re-implemented in the WMO community platform. The old country profiles now re-direct to the new ones.

-- https://community.wmo.int/

[amotl]

However, accessing resources like [5] or [6] currently croak with "The website encountered an unexpected error. Please try again later."

[5] https://community.wmo.int/members/deu
[6] https://community.wmo.int/members/fra

[amotl]

Finally, I found at least a HTML table outlining a mapping between WMO/WIGOS station identifiers and domestic DWD identifiers at [1]. Via [2], I found the DWD also publishes the same information in XLS format [3].

[1] https://www.dwd.de/DE/leistungen/klimadatendeutschland/stationsuebersicht.html
[2] https://www.dwd.de/EN/ourservices/surface_weather_observations/surface_weather_observations.html
[3] https://www.dwd.de/DE/leistungen/opendata/help/stationen/ha_messnetz.xls?__blob=publicationFile