Opened 8 years ago
Closed 7 years ago
#1053 closed help (worksforme)
Model instability
Reported by: | ab728 | Owned by: | luke |
---|---|---|---|
Component: | UM Model | Keywords: | |
Cc: | Platform: | <select platform> | |
UM Version: | 7.3 |
Description
Hi,
I have a job that crashes within UKCA with the following error message:
Resetting column after128 iterations
NO CONVERGENCE 1
The message is then repeated until NO CONVERGENCE 60. The crash occurs after 18 months. I have been having trouble with the sea ice ancillary file for a long time now but crashes due to this has thus far occurred within the first few timesteps. So I was wondering whether anything else could be causing this. I have yet to try halving the UKCA timestep. Would greatly appreciate any help!
Many thanks,
Tara
Change History (3)
comment:1 Changed 8 years ago by ab728
comment:2 Changed 8 years ago by luke
- Owner changed from um_support to luke
- Status changed from new to accepted
Hi Tara,
One of the interesting things here, assuming it is still related to your sea-ice problems, is that the model dies after nearly 6000 timesteps in that jobstep, rather than immediately on starting a new run.
I will look into this further.
Thanks,
Luke
comment:3 Changed 7 years ago by luke
- Resolution set to worksforme
- Status changed from accepted to closed
Hi Tara,
I don't think this is related to the sea-ice, but to a model instability that appears in the second-highest level of the atmosphere, which then causes a grid-point storm. It only seems to affect UKCA jobs with interactive ozone (and some form of stratospheric chemistry).
Including the branch
fcm:um_br/dev/luke/vn7.3_TOA_Temp_Fix/src
at revision 12609 seems to solve this problem.
Thanks,
Luke
I forgot to say the jobid is xhkqg and the .leave file is here:
/home/n02/n02/ab728/um/umui_out/xhkqg002.xhkqg.d13103.t201550.leave