This example represents a daily average valid on 2 January 2012 of a field produced by a real-time forecast started on 20120101 00Z. In this example, where the field is produced 6-hourly, the daily average valid on 20120102 is the average of steps 24, 30, 36 and 42.
- In bold, the values are fixed. They are meant to be used by all partners
- In green, these are the values for the example.
Time ( daily average ) | ||||||||
---|---|---|---|---|---|---|---|---|
Start of forecast ( section 1 ) | ||||||||
Octets reforecast Octets real time | values | Fixed | meaning of values | Grib_api keys | ||||
12 | Example | 12 | 12 | Significance of Reference Time | =1 | Start of forecast | = 1 | |
13-14 | 13-14 | Year (four digits) | 2012 | year of start of forecast | dataDate= | 201220120101 | 15dataTime=0 | |
15 | Month | 01 | month of start of forecast | = 01|||||
16 | 16 | Day | 01 | day of start of forecast | = 01||||
17 | 17 | Hour | 00 | hour of start of forecast | = 00||||
Daily average ( section 4 e.g. template 4.11 ) | ||||||||
18 | 18 | Indicator of unit of time range | = 11 | Hour | = 1 | 19-22|||
19-22 | Forecast time | 24 | Start of forecast + forecast time = start of average period | startStep=24 | ||||
45-46 | 38-39 | year of end of overall time interval | 2012 |
End of average period | = 2012 | 47
endStep=-48 | ||
40 | month of end of overall time interval | = | 01 | |||||
48 | 41 | day of end of overall time interval | = | 03 | ||||
49 | 42 | hour of end of overall time interval | = | 00 | ||||
52 | 45 | number of time ranges | =1 | Only one time statistics applied (average) | = 1 | 53-56|||
46-49 | total number of data values missing in statistical process | = 00 | = 0 | 57|||||
50 | Statistical process used to calculate the processed field from the field at each time increment during the time range | = 00 | Average | stepType= 0avg | ||||
58 | 51 | Type of time increment between successive fields used in the statistical processing | = 22 | Successive times processed have same start time of forecast, forecast time is incremented | = 2 | |||
59 | 52 | Indicator of unit of time for time range over which statistical processing is done | = 1111 | 6-hourly | indicatorOfUnitForTimeRange=11 | 60-63|||
53-56 | Length of the time range over which statistical processing is done, in units defined by the previous octet | = 44 | Daily average | lengthOfTimeRange=4 | ||||
64 | 57 | Indicator of unit of time for the increment between the successive fields used | = 11 | 6-hourly | indicatorOfUnitForTimeIncrement=11 | |||
65-68 | 58-61 | Time increment between successive fields, in units defined by the previous octet | 1 | Time frequency used to compute the daily mean | In the example, 1 means that 6-hourly outputs have been used to compute the average | timeIncrement=1 |
Examples of GRIB2 headers: