* Enable geothermal heating, stochastic pertubations, 3D KHTR, and MOM6_VERTICAL_GRID

[gustavo-marques]

Update the workhorse configuration (tx2_3v2) to include geothermal heating, stochastic pertubations, and 3D KHTR. By default, KHTR (mesoscale tracer diffusion) = KHTH (GM coefficient).

These are the changes needed to replicate the latest baselines:

• zstar - g.e23_a16g.GJRAv4.TL319_t232_zstar_N65.2024.015 NCAR/omwg_dev#14
• hycom1 - g.e23_a16g.GJRAv4.TL319_t232_hycom1_N75.2024.005 NCAR/omwg_dev#6 (PS: coordinate settings for hycom1 still need to be done manually)

This pull request modifies the answers, and I have confirmed that we can compare it bit-for-bit with 2024.015 without any additional namelist changes.

[mnlevy1981]

(PS: coordinate settings for hycom1 still need to be done manually)

What would you think about adding a MOM_vert_coord to env_run.xml with a default of zstar but allowing hybrid as well? Then we could add defaults to MOM_input.yaml that depend on MOM_vert_coord and all it would take to switch between zstar and hybrid would be an xmlchange call.

It might turn out to be a temporary addition to env_run.xml (if we eventually choose to support one or the other but not both) but I think it would be really useful during this testing phase. We could even use it to support comparing different hybrid coordinates, such as the one proposed by collaborators at U-Miami.

I'm happy to push changes to your branch to test it out.

[mnlevy1981]

This pull request modifies the answers, and I have confirmed that we can compare it bit-for-bit with NCAR/omwg_dev#14 without any additional namelist changes.

Do we need to set AUTO_MASKTABLE = False to be bit-for-bit?

[gustavo-marques]

This pull request modifies the answers, and I have confirmed that we can compare it bit-for-bit with NCAR/omwg_dev#14 without any additional namelist changes.

Do we need to set AUTO_MASKTABLE = False to be bit-for-bit?

Yes, we do need to set AUTO_MASKTABLE = False to be bit-for-bit. Thank you for asking that.

[gustavo-marques]

(PS: coordinate settings for hycom1 still need to be done manually)

What would you think about adding a MOM_vert_coord to env_run.xml with a default of zstar but allowing hybrid as well? Then we could add defaults to MOM_input.yaml that depend on MOM_vert_coord and all it would take to switch between zstar and hybrid would be an xmlchange call.

It might turn out to be a temporary addition to env_run.xml (if we eventually choose to support one or the other but not both) but I think it would be really useful during this testing phase. We could even use it to support comparing different hybrid coordinates, such as the one proposed by collaborators at U-Miami.

I'm happy to push changes to your branch to test it out.

I think this is a great idea. Thank you for suggesting a solution and offering to implement it.
Here are the changes needed when MOM_vert_coord = hycom1:

NK = 75
REGRIDDING_COORDINATE_MODE = "HYCOM1"
INTERPOLATION_SCHEME = "P1M_H2"
REMAPPING_SCHEME = "PPM_H4"
BOUNDARY_EXTRAPOLATION = True
ALE_COORDINATE_CONFIG = "HYBRID:hybrid_75layer_zstar2.50m-2020-11-23.nc,sigma2,dz"
REGRID_COMPRESSIBILITY_FRACTION = 0.01
MAXIMUM_INT_DEPTH_CONFIG = "FNC1:5,8000.0,1.0,.01"
MAX_LAYER_THICKNESS_CONFIG = "FNC1:400,31000.0,0.1,.01"
COORD_CONFIG = "ALE"

Please let me know how I can help with implementing or testing this feature.

[mnlevy1981]

@gustavo-marques 663d769 contains the code changes I showed you -- out of the box, tx2_3v2 still has the zstar_65L defaults, but you can run

$ ./xmlchange MOM6_VERTICAL_GRID=hycom1

to switch to hycom. We also talked about you adding hybgen to the valid values section and then updating MOM_input.yaml as appropriate. Lastly, I think I accounted for the tx0.25v1 grid correctly but somebody who actually runs quarter degree should probably verify that it's correct (it sounds like there might be updated tunings for the grid in the works)

[alperaltuntas]

Looks good to me. Has the aux_mom test suite been run, or should I run it?

[mnlevy1981]

aux_mom has not been run yet; I think answers will change in all the tests. It might make sense to add a hycom test to the test suite (just add ./xmlchange MOM6_VERTICAL_GRID=hycom1 to shell_commands)