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 ) | |||||||||
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Start of forecast ( section 1 ) | |||||||||
Octetsreforecast | Octets | values | Fixed values to be used by all the partners | Example | 12meaning of values | Grib_api keys | |||
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 | )18e.g. template 4.11 ) | ||||||||
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 | = 4 6 hourly fields used in average | 53-561 | Only one time statistics applied (average) | |||||
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= 0 | 58avg | |||
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 | = 1 | Hour | = 1 | 11 | 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 | = 244 | Daily average | lengthOfTimeRange= 24 | 644 | |||
57 | Indicator of unit of time for the increment between the successive fields used | = 1 | Hour | = 1 | 65-6811 | 6-hourly | indicatorOfUnitForTimeIncrement=11 | ||
58-61 | Time increment between successive fields, in units defined by the previous octet | 1 | Time frequency used to compute the daily mean | = 6 6 hourly fields used in average |
Time ( reforecast ) section 4, template 4.61 | ||
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Example | ||
38-39 | Year of model version | 2013 |
40 | Month of model version | 01 |
41 | Day of model version | 01 |
42 | Hour of model version | 00 |
43 | minute of model version | 00 |
44 | second of model version | 00 |
The example of reforecast with the example of daily average define together a reforecast of the daily average valid for 2/1/2012 computed with a model version operational on the 1/1/2013.
For real time forecast the template to be used is 4.11 and there isn't any information regarding the date and time of the model version.In the example, 1 means that 6-hourly outputs have been used to compute the average | timeIncrement=1 |
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Examples of GRIB2 headers: