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The daily aggregation refers to the union of the four 6-hourly intervals as defined in Table 8, therefore is the 24-hour period within the interval 21 UTC ≤ t < 21 UTC, where t is the observation time and the lower “21UTC” limit is the day before.
4.3.Monthly
The monthly aggregation refers to the union of all daily intervals within a given month. These daily intervals are established in 4.2. and are the basis for the monthly statistics, which are based on the aggregated daily results
4.4.Alert
The alert maps represent a 5-day moving average, therefore rely on daily values for a 5 day period as described in Table 9.
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