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A file, 'rcf' will be created by the model at each timestep when the restart files are written. This file contains the NAMELIST NAMRCF that informs the model what it needs to know to restart the model.
Do not delete or edit this file, otherwise the model will be unable to restart - regardless of whether the actual restart files (those beginning with srf) are present.
Conversely, if you don't want to run a restart but want to repeat the run, do delete the rcf file (and the srf files). If you don't the model will attempt to continue the run according to the namelist in the rcf file as this takes precedence over the namelists read from fort.4.
How to use a specific restart
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