WOMBAT-lite BGC is looking good - @pearseb tells me
Chlorophyll looks amazing
CO2 flux and iron limitation look great
Surface nitrate looks great, but surface iron is too high in coastal areas. Not sure why it’s not being removed rapidly at those concentrations.
Vert integrated NPP much too high in a weird place in the Amazon outflow. Otherwise it looks great. However, the weird high values are causing globally integrated rates of NPP that are 3x higher than the median estimate from observations. And much higher than what is considered reasonable.
CM3 seems stable with C-grid CICE and runoff spreading, so hopefully when we have runoff spreading in OM3 we can use C-grid CICE (OM3 runs without run-off have been CICE-C-grid stable)
MOM6-CICE6-WW3 100km OM3 config’ is switching to ePBL and has had substantive cost and speed improvements
basal melt latent heat being implemented, including distribution of meltwater/cooling at depth; distribution of frazil brine will be considered as a later step.
Add lines for ACCESS-OM2-01 (IAF cycle 1) to time series of global averages: temperature, salinity, sea surface temperature, sea surface salinity. Modify code here. GH Issue
Arctic transects in Transects.ipynb to explore the vertical extent of the SSS biases. Just use grid-aligned transects (which won’t be zonal or meridional, due to tripolar coordinates).
Spack develop help page being updated to focus on ACCESS-OM3. Call for testers!
ACCESS-OM2
full suite of configurations released, including new ocean/ice diagnostics and WOMBATlite bug fixes
includes @rmholmes et al. mixed layer heat budget diagnostics
2000-year 1° spin-up with WOMBATlite restarted
WOMBAT
first version of WOMBATfull released
Evaluation
Next evaluation meeting: 22 October 2026. Note
Call for Expressions of Interest (EoI) in ACCESS-ESM3 Model Evaluation & Development. Due: 31 October 2026 LINK.
Merged PRs (hooray!):
#139 Update MHT evaluation notebook (Claire Yung, 29 Sep). Splits meridional heat transport into the Atlantic and Indo-Pacific basins and adds observations for each basin, including Macdonald & Baringer 2013 values read off the plots in Tsujino et al. 2020.
#131 Manually calculated mixed layer depths (Katja Curtin, 27 Sep). Adds notebooks for mixed layer depths calculated by hand.
#130 Add floe size distribution analysis (Noah Day, 17 Sep)
C-grid CICE is currently the main performance bottleneck due to uneven ice workloads across MPI ranks and frequent MPI communication. Initial tests with optimised block sizes and more cores show ~6% faster runtime and ~3% lower SU cost, bringing the projected cost to ~235 kSU/year. This is still ~45% higher than ACCESS-OM2 0.1° (162 kSU/year), although the configurations are not directly comparable.
MC_100km_jra_iaf+wombatlite test 1 completed. Analysis is underway, with a few minor issues in the evaluation notebooks being resolved before the dataset is published.
New option under development to output CICE6 diagnostics as a separate file for each variable
Some ACCESS-CM2 datasets (e.g., cj877, by647) are no longer accessible under /g/data/p73/archive/non-CMIP, causing catalogue errors. Data may have been moved or removed. See issue #693.
Other
cosima.org.au website infrastructure upgrade - may be unavailable for a day or so this week or next. Please don’t edit the website until the upgrade is completed.
Bug at boundary in regional OM3 configurations - bug fix being tested: