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The C3S seasonal forecasting products are based on data from several state-of-the-art seasonal prediction systems. Multi-system combinations, as well as predictions from the individual component systems, are available. The centres currently providing forecasts to C3S are ECMWF, The Met Office and Météo-France; in the coming months data produced by Deutscher Wetterdienst and Centro Euro-Mediterraneo sui Cambiamenti Climatici will be included in the C3S multi-system.
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from 20171101
onwards
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(*) Due to some peculiarities of GRIB formatting and MetOffice forecasting system design, the value of the MARS keyword SYSTEM is changed on a yearly basis, so it has no direct relation with the model version of their system
Table 1: Values of the MARS keyword SYSTEM for the operational C3S seasonal contributors
Each model simulates the Earth system processes that influence weather patterns in slightly different ways, leading to different kinds of model error. The accumulated model errors become significant in comparison to the signal that is meant to be predicted. Some of those errors are shared by the different models but others are not, so combining the output from a number of models enables a more realistic representation of the uncertainties due to model error. The current scientific knowledge have shown that, in most cases, such combined forecasts are more skilful than forecasts from the best of the individual models.
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*** Note: check EUROSIP documentation (it is said that MMSA is not calculated for "lagged" ensembles)
| Dates | ECMWF | Météo-France | MetOffice (*) |
|---|---|---|---|
| from 20170901 to 20171001 | 4 | 5 | 12 |
from 20171101 | 5 | 5 | 12 |
(*) Due to some peculiarities of GRIB formatting and MetOffice forecasting system design, the value of the MARS keyword SYSTEM is changed on a yearly basis, so it has no direct relation with the model version of their system
Table 1: Values of the MARS keyword SYSTEM for the operational C3S seasonal contributors
High frequency data (stream MMSF)
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