As a developer, I want to understand how the WRES should handle WRDS thresholds from several sources and rating curves and implement it

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Author Name: Hank (Hank)
Original Redmine Issue: 99428, https://vlab.noaa.gov/redmine/issues/99428
Original Date: 2021-12-08

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The current behavior:

If a user requests WRDS NWS thresholds be included in the evaluation, then...

1. The "original" thresholds are always included in the evaluation and will have no label beyond the name of the thresholds; i.e., "minor", "action", etc.

2. Calculated thresholds are always included. If a @ratingProvider@ is specified, then only those calculated thresholds for that @rating_curve@ @source@ will be included. If not, then all rating curve calculated thresholds will be included. The label for the thresholds will be, "[rating provider] [threshold name]". For example, "NRLDB minor" or "USGS Rating Depot action".

3. If a @Provider@ is specified, indicating thresholds from a specific @threshold_source@ are desired, then the thresholds for that specific source are included in the evaluation. If not, then thresholds from +all+ sources that are available are evaluated. The threshold source is +not+ included in the threshold label, currently. This means that the "flood" for one source could overwrite the "flood" for a second source and we cannot be sure which one takes priority; it may be random.

The idea of this ticket is to get an idea about what behavior the user expects under different declarations and implement that behavior. The user has the ability to specify (or not specify) the @Provider@ (or WRDS @threshold_source@) and the @ratingProvider@ (or WRDS @rating_curve@ @source@). For each possible combination, how should the WRES react? (Or perhaps ask the user what they would like to able to do and adjust the options to meet their needs. That would likely be a breaking change and require GUI changes, however.)

Note that for recurrence flows, only the "original" thresholds are available and they are labeled "value" in the WRDS JSON. So the above doesn't apply to recurrence flows; we just need to ensure we don't break them when implementing changes for the NWS thresholds.

Leaving this in the backlog with high priority. It could become urgent if users start asking questions.

Thanks,

Hank

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Original Redmine Comment
Author Name: James (James)
Original Date: 2021-12-08T19:53:42Z

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I think we should fix item (3) on your list, but that is #97209. Beyond that, I would wait for a user to express surprise or ask for something more or different.