TWG - 4 Dec 2024
Attendees:
@MartinDix , @anton, @aekiss , @ezhilsabareesh8 , @helen , @cbull , @minghangli , @sofarrell , @angus-g
OM3-0.25 Project Board - Chris and others
- We are going to check the project board at weekly meetings to keep us focussed towards the 0.25 release
- Please fix the component labels for issues & correct any missing issues and their status
CICE C-grid instability - Anton
- Anton is still investigating the crash in the 0.25 degree configuration using CICE C-grid.
- Many perturbation experiments don’t crash, with various levels of instability persisting
- Its likely to the instability is as described in Lipscomb et al. 2007
- Anton is still working to confirm it’s not a coupling instability, although this is unlikely.
- There are many variables we are changing for other reasons which may mean the model will run ok with C-grid, e.g. update grid/bathymetry, move to 1080 barotropic timestep, JRA55 version 1.5
- It would be nice to figure out how hard to would be to run ocn & sea-ice components serially, although we don’t this this is viable for long runs due to performance reasons.
Performance - load balance (Minghang)
Has found the load imbalance for 0.25 degree needs more work - @manodeep (ACCESS-NRI SW Transformation) has provided some input on this.
Acknowledgments (Chris)
- We need to clarify who is best to acknowledge for projects, especially ACCESS-OM2, where ACCESS-NRI took on COSIMA products. Meeting happening this afternoon to formalise content for cosima page
OM2 0.1degree runs (Minghang)
- Need to clarify what the significant known issues are which would be improved by using the new ACCESS-NRI took release executable & config, rather than the historical cosima executable and data. @aekiss clarified this after the meeting, see [1].
- Goal is to provide a new reference run for researchers to compare their own runs against.
- We might update the RYF forcing to using JRA1.5, but otherwise won’t do any fixes to the currently released configuration.
Training schedule (Chris)
Next meeting:
18th Dec - Anton chair, Chris minutes
[1] Here’s a diff of the relevant commits.
and namelist tables
- MOM_input full table and diffs
- ice_in full table and diffs
Many of the differences don’t change the science, e.g. omitting parameters when they have the default value. Sec 5 of the tech report gives explanation for many of these.
Re: JRA55 updates. There’s info on JRA55-do v1.5.0 in these two issues JRA55 cyclones with incorrect sign · Issue #186 · COSIMA/access-om2 · GitHub and Support for JRA55-do v1.5.0 and v1.5.0.1 to get forcing up to ~present day · Issue #247 · COSIMA/access-om2 · GitHub. The backwards cyclones don’t affect RYF9091 JRA55 cyclones with incorrect sign · Issue #186 · COSIMA/access-om2 · GitHub and neither will the other fixes (see sec C.11 here) so I think RYF9091 will be very similar between v1.4 and v1.5, apart from whatever lingering effects the wrong cyclones (https://jra.kishou.go.jp/JRA-55/document/anti-cyclonic_TCs_L_en.txt) had on the JRA55 reanalysis.