Technical Working Group Meeting, March 2017


Date: 14th March 2017

  • Aidan Heerdegen, Scott Wales (ARCCSS, Acting Chair)
  • Nicholas Hannah (ARCCSS/Double Precision)
  • Russ Fiedler and Matt Chamberlain (CSIRO Hobart)
  • Peter Dobrohotoff (CSIRO Aspendale)

Updates on previous actions

  • MATM update: Nic will do a code review and document probably beginning of April.
  • CICE5.1 on repo: This will be part of the ACCESS-OM-0.1 development when this code is incorporated into the model
  • Matt has 1/10th data, and diagnostics were ok. Needed them to explore how heat is going into the ocean, and how that is affected by bulk formula and forcing fields. Could be useful analyses for changing to JRA55.


  • Nic time-stepping ACCESS-OM-0.1 with core forcing. Will not be working on this again for about a month. Is time stepping with CORE forcing CICE 4.1. Will add in cice5 and JRA55. Took about as long as he thought, but there were a number of issues that required fixing.
  • Nic wants to cleanup coupling code, remove cruft and commented out code. Also clean up date handling. There are twenty places where you have to change time step for example. Similar for run time. Need to set up regression tests to allow code changes without breaking stuff. In MOM and CICE namelists there are duplicate fields. Need code changes. Maybe C-style macros are a simple approach?
  • Nic Has developed some tools for generating model inputs required for ACCESS-OM. For example, creating the cice grid out of ocean grid. Using ESMF for creating grids and restarts. Started a wiki to document steps to develop config.


  • Russ is working on some mixing models, more complex than KPP. GOTM was patched on to MOM. Have to advect around a couple of extra tracers but doesn’t seem to impact speed much. Supposed to be a lot better way of mixing.
  • Russ has been having issues with number of retries time outs with PBS, occurs in first few lines of code. Aidan suggested noting error message and PBS ids and passing on to NCI Help, as this is often the side effect of a bad node.
  • Nic also having issues with tenth. Crashes, with lots of MPI output and no error code. A lot of the processors were sitting in an MPP_global call. ACCESS-OM coupling code was making it fall over. Raijin doesn’t like MPP_global operations as implemented by FMS. Due to implementation issues. To globally distribute an array in FMS you use MPP_global, which uses multiple MPI_Sends, rather than MPI_broadcast.
  • Peter: status is similar to last month’s update.
  • Russ has found issues with MLD diagnostic in MOM. If only have 3 levels returns zero. Strange issues near coast, getting zeroes at those locations.
  • Russ will be working on bathymetry for COSIMA 1/10th configuration. Maybe need different bathymetry for climate and BRANS type runs? Aidan was adamant the goal was to have the same bathymetry for all COSIMA models
  • Russ is running his 1/10th degree simulation with a 900s time step, whereas Aidan’s configuration is 450s due to instability in Arctic
  • JRA-55 is now being housed centrally. All those who wish to use it can they please make their requirements (versions, update frequency) known to the ARCCSS CMS team, and Paola Petrelli in particular

MOM5 Repo Move

  • Aidan has had some preliminary discussion with Stephen Griffies and Alistair Adcroft about having a new “official” home for the MOM5 source code repository. They favour a separate repo with the community supported model, and infrequent but regular updates of the “Official GFDL” repo version, which could be used by those needing a badge of officialness.
  • Nic felt that there was little point in having an “official” repo, especially if it just creates more work for little actual gain.
  • Nic was in favour of a standalone MOM github organisation, as it is bigger than any one of the groups that use it. It could also host all the older versions of MOM also. This was considered a good approach. If all partner organisations (COSIMA, ARCCSS, BoM, CSIRO, GFDL?) then gave this github organisation their support, similar to the CICE development model, this could tick the boxes for those that required an endorsed software product.



  • Nic to organise transferring MOM code repos to a new organisation MOM-ocean


  • Nic to present MATM code re-write proposal to TWG for feedback before sign-off. Will then be presented to Andy Hogg for approval.
  • Add Peter’s CICE5.1 config to OceansAus github repo (Nic and Peter)
  • Port MOM5 build system to cmake (Aidan)
  • Push updated MATM code with JRA-55 support to OceansAus github (Aidan)
  • Get licensing for MOM5 input files (Marshall)
  • Work on hosting MOM5 input files on NCI THREDDS server (Marshall, Aidan)
  • Nic create a discussion document (on COSIMA?) to document current approaches and strategies for future
  • Move FMS to submodule of MOM5 github repo (Marshall). Liase with Nic on implementation?
  • Test Nic’s access-om model config on OceansAus (All)
  • Work up test cases to cover the nudging code (Justin, Mirko) and supply them to Nic.
  • Move to CICE5 on OceansAus repo (Nic).
  • Add new test cases to Jenkins test suite (Nic).