As discussed in the ACCIBERG meeting (January 2026), I suggest following changes to openberg.py, based on the findings of my PhD work:
- Modified sea-ice-drag formulations with flexible threshold for a lock-in, and a concentration-dependent sea-ice-drag coefficient.
- Switches to disable the drag by sea ice, water and wind, similarly to what was implemented for wave_rad. The default is set to True, so that the drag is automatically enabled, but can be set to False by expert users.
Further recommendations:
- The fallback values of water, wind and sea ice velocities probably need to be set to zero (instead of None) for using switches for drag processes suggested above.
- Default for wave_rad should be set to False to disable highly unreliable wave forces. The default of stokes_drift should be set to True as it proved to contribute significantly in one of the studied cases. The default of melting should be set to True, as most iceberg drifts are impacted by melting.
The changes are implemented in the attached file. Note that I did not test this exact file but worked with the same implementations in an older version of openberg.py.
openberg_final.py
As discussed in the ACCIBERG meeting (January 2026), I suggest following changes to openberg.py, based on the findings of my PhD work:
Further recommendations:
The changes are implemented in the attached file. Note that I did not test this exact file but worked with the same implementations in an older version of openberg.py.
openberg_final.py