Hello, I’m a bit stumped on this and am hoping someone can find something I’ve overlooked! I am trying to set up a 3 member ensemble of AMIP historical free-running simulations from 1979 - 2014 (copies of u-dr799). My three members are run in suites : u-eb430 (using the default start dump) u-eb97…

Hi Isabelle. I’m trying to compare some other files from these runs just to check the evolution of some specific variables but it looks like there is some postprocessing going on which is moving or deleting files (e.g. *a.pa*)… $ ls u-eb974/run1/share/data/History_Data/*pa* u-eb974/run1/share/data…

Hi Johnny, I don’t know why those files would be moved. Is there a rose setting that moves/deletes files from History_Data? Thanks, Izzy

No problem. I’ll do a short test run now to see if I can reproduce what you’re seeing. Any differences from a perturbed restart file will show up very quickly anyway. :smiley: Cheers

Hi Isabelle. Could you please let me know how you are accessing mule on Monsoon3? It’s a requirement of perturb_theta.py. Are you loading a conda environment or similar? Thanks Jonny

Hi Isabelle. I’ve done a 1 month run of each of u-eb430, u-eb974, and u-eb982 I copied these exactly from your ~isabelle.sangha.ext/roses/u-.... directories. I do actually see marked changes in the results of the three runs and indeed u-eb982 seems to be heading towards a crash with some unphysica…

Hi again So for some reason perturb_theta.py works on ARCHER2 but not Monsoon3 for me. I’m doing a test now (on Monsoon3) using restarts generated from ARCHER2. I’ll let you know on Monday how it’s gotten on. Cheers Jonny

Hi Jonny, Thanks for looking into this. Are these runs done on Archer2 or Monsoon3? Mohit advised me to add this line : mule.stashmaster.STASHMASTER_PATH_PATTERN = ‘/projects/metoff/umdir/vn13.9/ctldata/STASHmaster/STASHmaster_A’ at the start of the perturb_theta.py to get it to run on Monsoon3. …

Perturbed start dump not changing run outputs

Unified Model

isangha 4 September 2026 12:20 6

Hi Jonny,

I do:

module load scitools

export PYTHONPATH=/projects/metoff/umdir/mule/mule-2025.10.1/python3.12.12_numpy-2.3.5/no-openmp/lib

module load um_tools

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Perturbed start dump not changing run outputs

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