KSEC1 element	Contents	GRIB octet	Recommended GRIB_API key	Coded GRIB_API keys	Comments
37	ECMWF local GRIB use definition identifier. 26 = MARS labeling or ensemble forecast data (with hindcast support).	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	Ensemble member number. Control forecast is number 0, perturbed forecasts ar-nne 1.	50	number	number
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
44	Reference date (YYYYMMDD)	52-55	referenceDate	referenceDate
-	Spare (set to zero).	56