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The source code changes to run OpenIFS 43r3 in nudged configuration are under version control in the OpenIFS Git repository in branch feature/nudging. The code in OpenIFS differs from that in IFS insofar that the variables CLPSHRLX and CLPGGRLX have been added to the namelist. These two variables allow to specify the location of the directory with the forcing files on the file system.
To enable nudging the namelist NAMRLX will need to be included in the namelist file fort.4.
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