Post a comment on the text below

Previous comments

• scheidand (Andreas Scheidleder) 22 Oct 2021 13:57:17

  Comment from AT

  Please delete this para. The recommendations for trend assessments in CIS guidance 18 solely refer to chemical data and NOT to quantity data. It was never discussed in the drafting group whether the recommended time window and the minimum length of years for chemical data also fit for GW level data because quantity trend assessment is not formally required by the WFD. Therefore it is not a good idea to refer to this guidance giving recommendations for GW quantity trend time series calculations. 5 years for quantity trends is probably too short.
  Reference should be (EC, 2009) and not (CIS, 2009)
  

  • zalllnih (Nihat Zal) 26 Nov 2021 15:50:08

    Thank you for your response. The reference to the CIS guidance is removed and the paragraph is changed as follows: “The minimum length of measurement series used for the calculation of the GLT is 5 annual records within a 20-year time window (2000 until 2019). Years are not necessarily consecutive. No gap filling was applied.”

    We agree that 5 years might be too short for thorough evaluation of long-term groundwater level trends. However, the available dataset was very limited. The methodology was developed with the intention to make best use of the capacity of the available groundwater level dataset. Therefore, we encourage the countries to report groundwater level data to the WISE-3 database  for improving the spatial representativeness, precision of the computation the indicator and the assessment on the GWL change in Europe.  

    Comment from AT

    Please delete this para. The recommendations for trend assessments in CIS guidance 18 solely refer to chemical data and NOT to quantity data. It was never discussed in the drafting group whether the recommended time window and the minimum length of years for chemical data also fit for GW level data because quantity trend assessment is not formally required by the WFD. Therefore it is not a good idea to refer to this guidance giving recommendations for GW quantity trend time series calculations. 5 years for quantity trends is probably too short.
    Reference should be (EC, 2009) and not (CIS, 2009)
    

     
    

• bednamal (Malgorzata Bednarek) 22 Oct 2021 16:38:28

  POLAND

  Inaccuracies in the description of the methodology - e.g. in the consulted material at the beginning of the methodology it is as follows: „The minimum length of measurement series used for the calculation of the GLT is 5 years within a 10-year time window, based on the recommendation of the WFD CIS document of quantitative status assessment (CIS, 2009). Years are not necessarily consecutive”, and then in part 2.7 Time coverage: „Period of analysis is 2000-2019; length of monitoring data series varies with minimum length of 5 years”. These two sentences do not have the same meaning.

  • zalllnih (Nihat Zal) 26 Nov 2021 15:50:42

    Thank you for your response. Inaccuracies in the description of the methodology are resolved. The approach concerning the minimum data requirements is as follows: The minimum length of measurement series used for the calculation of the GLT is 5 annual records within a 20-year time window (2000 until 2019). Years are not necessarily consecutive. No gap filling was applied.

    POLAND

    Inaccuracies in the description of the methodology - e.g. in the consulted material at the beginning of the methodology it is as follows: „The minimum length of measurement series used for the calculation of the GLT is 5 years within a 10-year time window, based on the recommendation of the WFD CIS document of quantitative status assessment (CIS, 2009). Years are not necessarily consecutive”, and then in part 2.7 Time coverage: „Period of analysis is 2000-2019; length of monitoring data series varies with minimum length of 5 years”. These two sentences do not have the same meaning.