GRIB2 - PRODUCT DEFINITION TEMPLATE 4.13

Derived forecasts based on a cluster of ensemble members over a rectangular area
at a horizontal level or in a horizontal layer in a continuous or non-continuous time interval

Created 09/21/2007


Octet No. Contents
10
Parameter category (see Code Table 4.1)
11
Parameter number (see Code Table 4.1)
12
Type of generating process (see Code Table 4.3)
13
Background generating process identifier (defined by originating centre)
14
Forecast generating process identifier (see Code ON388 Table A)
15-16
Hours after reference time data cut-off (see Note 1)
17
Minutes after reference time data cut-off
18
Indicator of unit of time range (see Code Table 4.4)
19-22
Forecast time in units defined by octet 18 (see Note 2)
23
Type of first fixed surface (see Code Table 4.5)
24
Scale factor of first fixed surface
25-28
Scaled value of first fixed surface
29
Type of second fixed surfaced (see Code Table 4.5)
30
Scale factor of second fixed surface
31-34
Scaled value of second fixed surfaces
35
Derived forecast (see Code Table 4.7)
36
Number of forecasts in the ensemble (N)
37
Cluster identifier
38
Number of cluster to which the high resolution control belongs
39
Number of cluster to which the high resolution control belongs
40
Total number of clusters
41
Clustering method (see Code Table 4.8)
42-45
Northern latitude of cluster domain
46-49
Southern latitude of cluster domain
50-53
eastern longitude of cluster domain
54-57
Western longitude of cluster domain
58
Nc - Number of forecasts in the cluster
59
Scale factor of standard deviation in the cluster
60-63
Scaled value of standard deviation in the cluster
64
Scale factor of distance of the cluster from ensemble mean
65-68
Scaled value of distance of the cluster from ensemble mean
69-70
Year of end of overall time interval
71
Month of end of overall time interval
72
Day of end of overall time overall time interval
73
Hour of end of overall time interval
74
Minute of end overall time interval
75
Second of end of overall time interval
76
n ― number of time range specifications describing the time intervals used to calculate the statistically-processed field
77-80
Total number of data values missing in the statistical process
81-92 Specification of the outermost (or only) time range over which statistical processing is done
81
Statistical process used to calculate the processed field from the field at each time increment during the time range
(see Code Table 4.10)
82
Type of time increment between successive fields used in the statistical processing (see Code Table 4.11)
83
Indicator of unit of time for time range over which statistical processing is done (see Code Table 4.4)
84-87
Length of the time range over which statistical processing is done, in units defined by the previous octet
88
Indicator of unit of time for the increment between the successive fields used (see Code Table 4.4)
89-92 Time increment between successive fields, in units defined by the previous octet (see Notes 3 and 4)
93-nn These octets are included only if n>1, where nn = 80 +12 x n
93-104
As octets 81 to 92, next innermost step of processing
105-nn
Additional time range specifications, included in accordance with the value of n, Contents as octets 81 to 92, repeated as necessary.
(nn+1)-(nn+Nc) List of Nc ensemble forecast numbers (Nc is given in octet 58)


Notes:

(1) Hours greater than 65534 will be coded as 65534.
(2) The reference time in section 1 and the forecast time together define the beginning of the overall time interval.
(3) An increment of zero means that the statistical processing is the result of a continuous (or near continuous) process, not the
processing of a number of discrete samples. Examples of such continuous processes are the temperatures measured by
analogue maximum and minimum thermometers or thermographs and the rainfall measured by a rain guage.
(4) The reference and forecast times are successively set to their initial values plus or minus the increment, as defined by
the type of time increment (one of octets 82, 94, 106 ...). For all but the innermost (last) time range, the next inner range
is then processed using these reference and forecast times as the initial references and forecast time.


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