saco.Dataset.infer_percentile_impact

Dataset.infer_percentile_impact(scenarios: List[str] = None, percentiles: List[int] = None, exclude_swabs_with_hofs: bool = True, exclude_gwabs: List[str] = None, exclude_swabs: List[str] = None)

Infer impacts at percentile(s) from a mean abstraction for a scenario(s).

Parameters:

  • scenarios – Abbreviation of artificial influences scenarios for which calculations should be performed. Defaults to all in Dataset.

  • percentiles – Flow percentiled (natural) for which calculations should be performed. Defaults to all in Dataset.

  • exclude_swabs_with_hofs – Whether to exclude SWABS with HOFs from impact calculations.

  • exclude_gwabs – Groundwater abstractions to exclude from updated impact calculations. List should contain entries from UNIQUEID in GWABs_NBB.

  • exclude_swabs – Surface water abstractions to exclude from updated impact calculations. List should contain entries from UNIQUEID in SWABS_NBB.

Notes

WRGIS models the relationships between long-term average abstraction and impacts at different flow percentiles. For GWABS, the calculations are based on the “IMPFAC” field in GWABs_NBB. For SWABS, the calculations draw on the start/end months in SWABS_NBB, which are used to identify relevant factors in the Seasonal_Lookup table.

This method performs these calculations for GWABS and SWABS. Complex abstractions/impacts in the SupResGW_NBB table are not handled. The impacts for each scenario/percentile combination calculated by this method account for local consumptiveness. In contrast, the long-term average abstractions that form an “input” to the calculations should exclude the effects of local consumptiveness. See the notes for the infer_mean_abstraction method for further details.

Lists of abstractions to be excluded from long-term average calculations can be supplied via the exclude_gwabs and exclude_swabs arguments. Abstractions to be excluded should be specified using their UNIQUEID.

It is assumed that the relevant long-term average columns are already present in the relevant tables before this method is called.

It is also assumed that the relevant scenario/percentile impact columns are already present before this method is called. The role of the method is to update these impacts for any abstractions that are not listed in exclude_gwabs or exclude_swabs arguments.

Finally, we note that the impacts calculated by this method are “unconstrained”. They are not limited by the actual available flow in a waterbody, which might mean that the impacts are not fully realisable. In addition, the impacts calculated by this method are not guaranteed to respect any HOF conditions. See Calculator.__init__ for further guidance on this point.