The MARS data catalogue and associated data files can be browsed through the web page https://apps.ecmwf.int/mars-catalogue/, which also lists the available CEMS-EFAS data.
Navigation is done by clicking on links on each pages.
EFAS data is stored under the special datasets 'Copernicus Emergency Management Service (CEMS).
Within the Copernicus Emergency Management Service (CEMS) page, EFAS data is organised in two 'streams':
Each stream is accessible by clicking on the associated link; for example here 'operational model'
In MARS, data are coded as 'stream' and 'class'. After selected the type of data of interest, the associated code is highlighted in bold under the “Current selection” section. The selection can also be modified clicking on an alternative code.
Within the EFAS operational model section, two versions are available:
Data published within version 1 always correspond to the latest operational forecasts and should be the default choice. Only very special cases would require accessing data from the version 9001/ test system, and only version 1 is recommended to use.
Once selecting a data type (here Forecast), the list of years with available data is shown, then when selecting a specific year, the list of months with available data is shown.
Note the type corresponding to 'Forecast' is fc (shown in bold).
Once a month has been selected (here March), the list of 'parameters' (or variable type) available is shown.
EFAS available variables are organised in two categories:
Once the type of level has been selected (here soil levels), the list of meteorological forecast models used to produce the forecast (or 'origin') is shown.
In EFAS, simulations from two deterministic meteorological forecast models are available: DWD and ECMWF
Once the 'origin' has been selected (here ECMWF), the different attributes of the available data can be selected. They include:
After selecting the attributes (no selection will obtain the entire dataset), the data can be downloaded directly by clicking on 'Retrieve the selection in GRIB' or through a MARS request as code by clicking 'View the MARS request'.
Note that retrieving EFAS data in netCDF is not possible directly from MARS.
The "View the MARS request" page shows all MARS codes corresponding to the selection. Similar codes can be used for automatic retrievals/ customised requests using scripting languages.
For more information on how to use the MARS scripting to customize your retrievals please refer directly to the MARS user guide.
To get access through the ECMWF Web API, please see documentation here.