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 |  |  |