With the release of the October 2024 real-time forecast a new variable, volumetric soil moisture, has been included in the C3S seasonal forecast datasets available through the Climate Data Store (CDS). Users should be aware of the following elements:
- This variable will only be available in the
seasonal-original-single-levelsdataset of the CDS, which means only high temporal frequency data (daily) will be available and no monthly aggregations nor anomalies will be published for the time being. - This variable will be made available for all the soil model levels used by each forecast system
- The volumetric soil moisture data has been encoded in GRIB2 using CCSDS packing.
- This would require users to have access to recent versions of GRIB decoding software (recommended ecCodes >= 2.33)
- The encoding in GRIB2 was needed to cater for the multiple soil levels.
- Note this also applies to ECMWF SEAS5 data available through the CDS (the encoding of the corresponding data in the original archive is GRIB1 with parameters 39, 40, 41 and 42)
- At the time of this announcement this variable will be only available for the following forecast systems:
- ECMWF SEAS5 (system=51); UK MetOffice GloSea6 (system=602, 603); ECCC CanSIPSv3.0 (CanESM5.1p1bc, system=4 and GEM5.2-NEMO, system=5)
- The European forecast systems with imminent version upgrades will include this variable only in their new versions: CMCC SPS4 (system=4), DWD GCFS2.2 (system=22) and Météo-France System9 (system=9)