KSEC1 element Contents GRIB octet Recommended GRIB_API keys
 Coded GRIB_API keys
 Comments
37 
ECMWF local GRIB use definition identifier.
1 = MARS labeling or ensemble forecast data.
 41 localDefinitionNumber
 localDefinitionNumber
38 Class 42 class
 marsClass
39 Type 43 type
 marsType
40 Stream 44-45 stream
 marsStream
41 
Version number or experiment identifier.
(4 ASCII characters, right justified)
 46-49 expver
 experimentVersionNumber
42 
Set to 0 for MARS labeling (simple labeling).
When element 40 = 1035, this is the ensemble forecast number.
When element 39 = 10, this is the control forecast number and is set to 0.
When element 39 = 11, this is the perturbed forecast number in some range 1-nn.
Positive perturbations have odd numbers and negative have even numbers. They
go in pairs (1,2), (3,4) etc.
When element 39 = 17, this is an ensemble mean and the number is set to 0.
When element 39 = 18, this is an ensemble standard deviation and the number
is set to 0.
 50 number
 perturbationNumber
43 Set to 0, if not an ensemble forecast. Otherwise, the total number of forecasts in an ensemble; the number includes the control forecast. 51 numberOfForecastsInEnsemble
 numberOfForecastsInEnsemble
- Spare (set to zero). 52