Detailed model description
Page containing details for all model configurations available in S2S since the project start => CNRM model description
Overview of the model changes
For next model change be aware of Issues with data#Meteo-France(lfpw) => to be fixed!
| Model version | Implement. date in S2S | Time range | Resolution | Ens. Size | Frequency | Re-forecasts | Rfc period | Rfc frequency | Rfc size | Ocean resolution | Active Sea Ice | Remarks |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| CNRM-CM | 06/11/2025 | d 0-46 | T359 L137 | 25 | weekly (Thu) | fixed | 1999-2024 (model version date 01/06/2025) | 4/month (always on the 1st, 9th, 17th and 25th) | 11 | 0.25° L75 | yes | new fixed reforecast set to be archived |
CNRM-CM 6.1 | 22/10/2020 | d 0-47 | T359 L91 | 25 | weekly (Thu) | fixed | 1993-2017 (model version date 01/07/2019) | every 7 days (starting from 31/12/1992 *2) | 10 | 0.25° L75 | yes | additional ocean parameters added since For next model change be aware of Issues with data#Meteo-France(lfpw) => to be fixed! |
CNRM-CM 6.0 | 01/03/2016 | d 0-32 | T255 L91 | 51 | weekly (Thu) | fixed | 1993-2014 (model version date 01/12/2014) | 4/month (always on the 1st, 8th, 15th and 22nd *2) | 15 | 1° L42 | yes |
Description of the main changes
CNRM-CM 6.2
- operational since 06/11/2025 (included)
- the corresponding fixed reforecast set is with the model version date 2025-06-01
Differences to the current system are:
- ensemble size of the hindcast will be 11 members instead of 10
- forecast/hindcast length will be 46 days instead of 47
Apart from that, the parameters provided are the same, with a few corrections following S2S original requests:
- sea ice fraction and SST will now be provided on the S2S 1.5° grid
- issus with max and min temperatures is fixed (in the current system, Tmax and Tmin are identical, by mistake)
- latitudes are sorted from +90 to -90, as requested.
- on pressure levels:
- specific humidity is removed from 10, 50, 100 hPa levels
- vertical velocity is added to 10 hPa level
- new pressure level is added 1000 hPa
CNRM-CM 6.1
- operational since 22/10/2020 (included)
- the corresponding fixed reforecast set is with the model version date 2019-07-01
- the forecast length was prolonged to 47 days (from 32)
- the ensemble size was decreased to 25 (from 51) for the real-time data and to 10 (from 15) for the reforecasts
- Additional parameters added:
- CAPE
- Skin Temperature
- Soil Moisture (top 20 and 100 cm)
- Soil temperature (top 20 and 100 cm)
- Surface water runoff
- 9 ocean fields (Average potential temperature in the upper 300 m, Average salinity in the upper 300 m, Depth of 20 C isotherm, Eastward sea water velocity, Northward sea water velocity, Mixed layer depth, Sea-ice thickness, Sea surface height, Sea water practical salinity)
- 10 metre wind U / V is archived now as 6-hourly in contrary to once per day before
- No-longer available parameters:
- Potential vorticity
- For all pressure level fields : level 1000 hPa will be missing
- For vertical velocity only, 10 hPa level will be missing in addition to level 1000 hPa