ACCESS-OM2-01

ACCESS-OM2-01 is currently being prepared as the flagship Australian high-resolution ocean-sea ice model.

It uses the MOM5.1 ocean with 0.1° lateral resolution at the Equator, tripolar in the north and Mercator projection down to 65°S, with 75 vertical levels. The sea ice model is CICE5.1, coupled with the OASIS3-MCT coupler. The model is forced with the JRA55-do v1.3 forcing dataset.

The model configuration is tracked with version control and is available as part of the ACCESS-OM2 suite at github.com/OceansAus/access-om. Full instructions for obtaining the source code, compiling and running the model are also at the same location.

Model Performance

Typical processor configurations for ACCESS-OM2-01 on Raijin are:

  • 4394 cores for the MOM5.1 ocean;
  • 1200 cores for the CICE5 sea ice model;
  • 1 core for the MATM atmosphere;
  • totalling 5600 cores.

The model is expected to scale to much larger core counts, but simulations exceeding 10% of the machine are not feasible.

Default simulations use a 600 second timestep. We are currently expecting runtimes of 8-9 hours per model year on the Broadwell nodes (~3 model years per day at full capacity), however optimisation, load balancing and scaling for this model is an ongoing task.

Model Output

Results from the model will be released freely for community use. When available, preliminary spinup results are housed in /g/data3/hh5/tmp/cosima/access-om2-01/ on NCI; in the longer term data will be published through the NCI data repository.