The workflow is as follows

# run 10 years saving the restarts
run_nemo -p param/param.cfg -s

once this run finishes the other two can be lounched:

#this one is because we need output.init.nc file, and from the previuos one we just have restarts.
run_nemo -p param/param_init_state.cfg -s

#this one will save the initial state generate from the restart of the first one + white noise on the temperature
run_nemo -p param/param_pert.cfg -s

at this point run

python3 RMSE.py  init_state.nc inital_state_pert.nc

the two files will be found in the run folder of the respective runs.
From the output save the variables that differs more than say 10^(-7), and set an analysis with
error_thresholds = {"votemper": 0.0007167909394343306,
                    "vozocrtx": 7.003275906953925e-07,
                    "vomecrty": 6.99310434885036e-07,
                    "sohefldo": 0.00885575338581615,
                    "sozotaux": 1.0108048009931158e-06,
                    "sometauy": 1.1480837664543964e-06}
                    
The result of the analisys should be
  gdept_n  main	             dom_oce
  gde3w_n  main	             dom_oce
  zn	   eos_insitu_pot	              eosbn2
  zn0	   eos_insitu_pot	              eosbn2
  dta	   fld_interp	             fldread