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Note that for reasons related with the availability of computing resources, the hindcasts usually have fewer ensemble members per start date than the real-time forecasts, e.g. ECMWF SEAS5 5 has 51 members for the real-time forecasts, and just 25 members for the hindcasts.

How the seasonal forecasting systems build their ensembles? "Burst" mode versus "lagged" mode

N members at 1st month

N members at specific dates (different production schedules)

Production schedules in seasonal forecasting systems

Table with production per system and per forecast/hindcast type

Description of the c3s-seasonal dataset in the MARS archive

Data tree

MMSF

MSMM

MMSA

*** Note: check EUROSIP documentation (it is said that MMSA is not calculated for "lagged" ensembles)

High frequency data (stream MMSF)

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