Regional ice/ocean restart issue

[kshedstrom]

The ice gets its view of the ocean surface currents via Ocean%[uv]_surf and Ice%[uv]_surf. These things have no halo points and in fact assume symmetric=.false. so they are missing the points at one edge each. If one wants MERGED_CONTINUITY=True and ice OBCs, this will have to change. On restart, things are subtly different in these surface velocities, leading to small changes in the flux calculations.

[Hallberg-NOAA]

Thank you for pointing this problem out. Theresa Morrison and I are working on a solution, but it may involve substantially restructuring of how the SIS2 and MOM6 code communicate with each other, at least with some settings. I suspect that we will only be able to solve this issue if the coupling between SIS2 and MOM6 avoids the FMS_coupler code, and instead goes via the code in SIS2/src/combined_ice_ocean_driver.F90. Do you think that this would be an acceptable solution for you?

[kshedstrom]

Yes, that sounds fine. Actually, if we use your new OBCmaskCu, OBCmaskCv on the wind stresses, this whole problem would go away. What do you think of that?