Arpege namelist has to be updated for each run of the model, and for taking into account some parameters that can evolve during an experiment through the history file. From version 6.1, ECLIS can help using the same namelist for various configurations (coupled or not, changing procs number ...).

By default, the namelist update is done by script ECLIS/toolbox/update_namarp.sh ; but you can have ECLIS use your own script, by setting ECLIS parameter UPDNAMARP to the script’s path

From ECLIS V6.1, the standard update script has the following behaviour :

Parameters which are forced

• NFRCPL forced to a value consistent with ECLIS parameter FRCPL, using the time step value read in the namelist
• NSTOP forced according to first and last dates of the current run
• NPROC set based on value in relan _his file,
• NINDAT set to the relevant value
• NSSSSS set to the relevant value
• NFRHIS set to NFRPOS or NSTOP depending on the flag for saving all restarts,

Parameters which ECLIS will set only if keyword AUTO is used (otherwise, it will let your value unchanged)

• LMCC03 set depending on the use of the coupler
• NFRPOS derived from NHH (the number of hours between each post-processing) and TSTEP
• NFRSFXHIS derived from SFXSTEPOUT if it is set, otherwise from NFRPOS
• NFRCORM set to NFRPOS
• NFRRAZ set to NFRPOS
• NPRTRW set as the largest divider of NPROC less than NDGLG,
• NPRTRV set to NPROC/NPRTRW,
• NPRGPEW ECLIS will unset it, in order that Arpege chooses it, based on NPRGPNS and what its Cycle allows,

Parameters which ECLIS will set to NPROC, only if keyword AUTO or NPROC is used (otherwise, it will let your value unchanged)

• NPRGPNS
• NSTRIN
• NSTROUT

Recommended settings for NAMPAR0, for Arpege V6 and ECLIS > V6.3

• NPROC, NPRTRW, NPRTRV, NPRGPNS, and NPRGPEW should be set to AUTO