The detail of Climatological quintile boundaries

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1

We are very grateful to ECMWF for giving us this opportunity to participate in the competition, and we have a few small questions that we hope to get some clarification on.

  1. Regarding the explanation of “Climatological quintile boundaries” — does the description “calculated from 20 years of historical weekly data aggregated into weekly statistics” refer specifically to the period from 2005 to 2024?
  2. The function
    clim_quintile_bounds = retrieve_evaluation_data.retrieve_20yr_quintile_boundaries(<<date>>, <<variable>>, <<password>>, local_destination=None)
    appears to only retrieve climatological quintile boundaries for a single day. Would it be possible to provide the full set of daily climatological quintile boundaries for an entire year, to make it easier for local calculations?

Thank you very much in advance for your help!

2

Hi Peng,

  1. The period used to calculate climatological quintile boundaries is based on the previous 20 years. Therefore, for forecasts initialised in 2025, the 20 year period is 2005 to 2024 (inclusive) but for forecasts initialised in 2026, the 20 year period is 2006 to 2025 (inclusive).
  2. Climatological quintile boundaries are only available for every Monday from 1999 to 2025. I would recommend a for loop if you’d like to download all climatologies associated with a Monday start date.

Kind regards,
Josh

3

Dear Josh
Thank you for your quick and detailed reply!
Best wishes
Peng