For instantaneous fields, a monthly mean is the mean of the fields sampled at the specified averaging period.

For accumulated fields, a monthly mean is the mean rate of accumulation of the fields.

KSEC1 element Contents GRIB octet Recommended GRIB_API keys Coded GRIB_API keys Comments

37
ECMWF local GRIB use definition identifier.
31 = EUROSIP products
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
Number
Ensemble member number.
Control forecast is number 0,
perturbed forecasts 1-nn.

50 number
perturbationNumber

43 Number of forecasts in ensemble 51 numberOfForecastsInEnsemble
numberOfForecastsInEnsemble

44 Forecast month 52-53 forecastMonth
forecastMonth

45 Date of forecast run 54-57 dateOfForecastRun
dateOfForecastRun

46 Number of models 58 numberOfModels
numberOfModels

- set to zero 59-100

47 - 27 + numberOfModels Model identifier 101 - 101 + numberOfModels*2 modelIdentifier
modelIdentifier

- Spare (set to zero) 101 + numberOfModels*2+1 - 240

KSEC1 element	Contents	GRIB octet	Recommended GRIB_API keys	Coded GRIB_API keys
37	ECMWF local GRIB use definition identifier. 31 = EUROSIP products	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	Number Ensemble member number. Control forecast is number 0, perturbed forecasts 1-nn.	50	number	perturbationNumber
43	Number of forecasts in ensemble	51	numberOfForecastsInEnsemble	numberOfForecastsInEnsemble
44	Forecast month	52-53	forecastMonth	forecastMonth
45	Date of forecast run	54-57	dateOfForecastRun	dateOfForecastRun
46	Number of models	58	numberOfModels	numberOfModels
-	set to zero	59-100
47 - 27 + numberOfModels	Model identifier	101 - 101 + numberOfModels*2	modelIdentifier	modelIdentifier
-	Spare (set to zero)	101 + numberOfModels*2+1 - 240