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Step-by-step guide

Local tables for parameters

A common candidate for local adaptation is the handling of local parameters. The standard parameter descriptions are contained in the files name.def, paramId.def, shortName.def and units.def in directories:

/usr/local/share/eccodes/definitions/grib[edition]

The parameter descriptions for a given centre are contained in the directories:

/usr/local/share/eccodes/definitions/grib[edition]/localConcepts/[centre:s]

The following are examples of the contents for the above files in order to handle ECMWF parameter Geopotential in GRIB edition 1:

#Geopotential
'Geopotential' = {
         table2Version = 128 ;
         indicatorOfParameter = 129 ;
        }

 #Geopotential
'129' = {
         table2Version = 128 ;
         indicatorOfParameter = 129 ;
        }

#Geopotential
'z' = {
         table2Version = 128 ;
         indicatorOfParameter = 129 ;
        } 

#Geopotential
'm**2 s**-2' = {
         table2Version = 128 ;
         indicatorOfParameter = 129 ;
        }

In GRIB edition 2, the contents of the same files for parameter Geopotential are:

#Geopotential
'Geopotential' = {
         discipline = 0 ;
         parameterCategory = 3 ;
         parameterNumber = 4 ;
        }

 #Geopotential
'129' = {
         discipline = 0 ;
         parameterCategory = 3 ;
         parameterNumber = 4 ;
        }

#Geopotential
'z' = {
         discipline = 0 ;
         parameterCategory = 3 ;
         parameterNumber = 4 ;
        }

#Geopotential
'm**2 s**-2' = {
         discipline = 0 ;
         parameterCategory = 3 ;
         parameterNumber = 4 ;
        }

Local Definitions (Local Use section)

Local definitions are also required when one needs to store information which is not part of the standard GRIB header. This would typically be a MARS key (like class, stream, type and version number or experiment identifier, expver) or information that the data producer wants to have in each GRIB for convenience.

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# GRIBcode   Acronym    Long name
1001         eebc       Ensemble using ECMWF data as Boundary Conditions
1002         eeic       Ensemble using ECMWF data as Initial Conditions

Local tables for parameters

Another candidate for local adaptation is the handling of local parameters. The standard parameter descriptions are contained in the files name.def, paramId.def, shortName.def and units.def in directories:

/usr/local/share/eccodes/definitions/grib[edition]

The parameter descriptions for a given centre are contained in the files directories:

/usr/local/share/eccodes/definitions/grib[edition]/localConcepts/[centre:s]

The following are examples of the contents for the above files in order to handle ECMWF parameter Geopotential in GRIB edition 1:

#Geopotential
'Geopotential' = {
         table2Version = 128 ;
         indicatorOfParameter = 129 ;
        }

 #Geopotential
'129' = {
         table2Version = 128 ;
         indicatorOfParameter = 129 ;
        }

#Geopotential
'z' = {
         table2Version = 128 ;
         indicatorOfParameter = 129 ;
        } 

#Geopotential
'm**2 s**-2' = {
         table2Version = 128 ;
         indicatorOfParameter = 129 ;
        }

In GRIB edition 2, the contents of the same files for parameter Geopotential are:

#Geopotential
'Geopotential' = {
         discipline = 0 ;
         parameterCategory = 3 ;
         parameterNumber = 4 ;
        }

 #Geopotential
'129' = {
         discipline = 0 ;
         parameterCategory = 3 ;
         parameterNumber = 4 ;
        }

#Geopotential
'z' = {
         discipline = 0 ;
         parameterCategory = 3 ;
         parameterNumber = 4 ;
        }

#Geopotential
'm**2 s**-2' = {
         discipline = 0 ;
         parameterCategory = 3 ;
         parameterNumber = 4 ;
        }

Install and test your changes

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