What is GRIB?

GRIB (GRIdded Binary or General Regularly-distributed Information in Binary form) is a common data format used in meteorology and standardised by the World Meteorological Organisation.

• There are two versions of GRIB: GRIB edition 1 (GRIB1) and edition 2 (GRIB2).
• CEMS-Flood data is available in GRIB2.
• It is archieved in GRIB2 in the Meteorological Archival and Retrieval System (MARS) at ECMWF, see the MARS user documentation for further information.
• Further information on the data format is available in the What are GRIB files page on the Copernicus Knowledge Base.

Working with GRIB2 files

There are 2 principal ways to work with GRIB2 files:

      1. ecCodes

A library developed at ECMWF consisting of a set of tools to code and decode GRIBs, as well as other formats. The eccodes command-line utilities are commonly used by the meteorology community. Please consult the Copernicus Knowledge Base page How to read GRIB files for an overview of the commands available.

      2. CFGRIB

A Python interface to the eccodes library. It is one of the supported backends of Xarray. Please consult the Open CEMS-Flood data page for example of using CFGRIB with CEMS-Flood data.