Division 2 Criteria
United Kingdom
The following criteria shall be used for checking validity when aggregating data and calculating statistical parameters:
| In cases where all possible measured data are not available, the following factor shall be used to calculate AOT40 values:
(*) being the number of hours within the time period of AOT40 definition, (i.e. 08:00 to 20:00 CET from 1 May to 31 July each year, for vegetation protection and from 1 April to 30 September each year for forest protection). | ||||
| Parameter | Required proportion of valid data | |||
|---|---|---|---|---|
| One hour values | 75 % (i.e. 45 minutes) | |||
| Eight hours values | 75 % of values (i.e. six hours) | |||
| Maximum daily 8 hours mean from hourly running 8 hours | 75 % of the hourly running eight hours averages (i.e. 18 eight-hourly averages per day) | |||
| AOT40 | 90 % of the one hour values over the time period defined for calculating the AOT40 valuef1 | |||
| Annual mean | 75 % of the one hour values over summer (April to September) and 75 % over winter (January to March, October to December) seasons separately | |||
| Number of exceedances and maximum values per month | 90 % of the daily maximum eight hours mean values (27 available daily values per month) 90 % of the one hour values between 8.00 and 20.00 CET | |||
| Number of exceedances and maximum values per year | five out of six months over the summer season (April to September) | |||
Annotations
Footnotes
- f1
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In cases where all possible measured data are not available, the following factor shall be used to calculate AOT40 values:
AOT40estimate = AOT40measured × total possible number of hours (*) number of measured hourly values (*)
being the number of hours within the time period of AOT40 definition, (i.e. 08:00 to 20:00 CET from 1 May to 31 July each year, for vegetation protection and from 1 April to 30 September each year for forest protection).