Add two-way ocean-wave coupling feature to the HAFS applications

[binli2337]

Commit Queue Requirements:

• Fill out all sections of this template.
• All sub component pull requests have been reviewed by their code managers.
• Run the full Intel+GNU RT suite (compared to current baselines) on either Hera/Derecho/Hercules
• Commit 'test_changes.list' from previous step

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Description:

The ufs-weather-model will be updated to include two-way ocean-wave coupling capability for HAFS applications.

Commit Message:

  * CMEPS - CMEPS is updated to transfer ocean-current fields from MOM6 to WW3 and to transfer the Stokes drift components from WW3 to MOM6 for the HAFS applications.
  * MOM6 - MOM6 cap is updated to convert a missing value to zero for the imported Stokes drift components for the ufs.hafs applications.
  * WW3 - WW3 cap is updated to convert a missing value to zero for the imported ocean-current fields for the ufs.hafs applications.
 

Priority:

• Normal

Git Tracking

UFSWM:

• Closes Update HAFS applications to include 2-way ocean-wave coupling capability #2582

Sub component Pull Requests:

• CMEPS: Update CMEPS for 2-way ocean-wave coupling in HAFS NOAA-EMC/CMEPS#133
• MOM6: Update MOM6 cap for 2-way ocean-wave coupling for HAFS NOAA-EMC/MOM6#143
• WW3: Update WW3 cap for 2-way ocean-wave coupling NOAA-EMC/WW3#1348

UFSWM Blocking Dependencies:

• Blocked by #
• None

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Changes

Regression Test Changes (Please commit test_changes.list):

• PR Updates/Changes Baselines.

Input data Changes:

• Updated input data is located at /scratch1/NCEPDEV/hwrf/save/Bin.Li/UFS-WM_RT/NEMSfv3gfs/input-data-20240501/WW3_input_data_20250114/mod_def.natl_6m.

Library Changes/Upgrades:

• No Updates

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Testing Log:

• RDHPCS
  • Hera
  • Orion
  • Hercules
  • Jet
  • GaeaC5
  • GaeaC6
  • Derecho
• WCOSS2
  • Dogwood/Cactus
  • Acorn
• CI
• opnReqTest (complete task if unnecessary)

[DeniseWorthen]

@binli2337 Don't you know the value which will be sent from non-overlapped regions (ie, the fillvalue). Why is it necessary to check for the difference between the field and the fillvalue ... for example in MOM6 : abs(stkx(i,j,ib)-fillValue) <= 0.01 ?

[binli2337]

@DeniseWorthen When comparing floating point numbers, it is generally recommended to check if the absolute difference between the two numbers is less than a tiny value. In this specific case, since stkx and fillvalue are constant, it is probably not necessary to check the absolute difference. Thanks for reviewing the code.

[DeniseWorthen]

@binli2337 If your argument about 'checking small differences' pertains, then shouldn't you make sure both components are tested?

if( (trim(casename) == "ufs.hafs") .and. (abs(stkx(i,j,ib)-fillValue) <= 0.01) ) then
              ice_ocean_boundary%ustkb(i,j,ib) = 0.0
              ice_ocean_boundary%vstkb(i,j,ib) = 0.0
            else

[binli2337]

@DeniseWorthen In the related CMEPS PR, the Stokes drift components for the x direction and the y direction are filled with the fill value in the same non-overlapped areas (from line 603 to line 610 in the esmFldsExchange_hafs_mod.F90 file). So in the MOM6 PR, when stkx has the fill value, the stky will always has the same fill value. Checking whether abs(stky(i,j,ib)-fillValue) is less than a small number is not needed.

[DeniseWorthen]

@binli2337 I'm confused how you are using waves in MOM6 w/o updating your MOM_input. When I look at the file
ufs.hafs.cpl.hi.2020-08-25-54000.nc in the hafs_regional_storm_following_1nest_atm_ocn_wav_mom6_intel test, there are no stokes fields exported to OCN. There are only stokes fields imported from WAV.

[DeniseWorthen]

See this code from the MOM cap

  call query_ocean_state(ocean_state, use_waves=use_waves, wave_method=wave_method)
  if (use_waves) then
    if (wave_method == "EFACTOR") then
      allocate( Ice_ocean_boundary%lamult(isc:iec,jsc:jec) )
      Ice_ocean_boundary%lamult          = 0.0
    else if (wave_method == "SURFACE_BANDS") then
      call query_ocean_state(ocean_state, NumWaveBands=Ice_ocean_boundary%num_stk_bands)
      allocate(Ice_ocean_boundary%ustkb(isc:iec,jsc:jec,Ice_ocean_boundary%num_stk_bands), source=0.0)
      allocate(Ice_ocean_boundary%vstkb(isc:iec,jsc:jec,Ice_ocean_boundary%num_stk_bands), source=0.0)
      allocate(Ice_ocean_boundary%stk_wavenumbers(Ice_ocean_boundary%num_stk_bands), source=0.0)
      call query_ocean_state(ocean_state, WaveNumbers=Ice_ocean_boundary%stk_wavenumbers, unscale=.true.)
    else
      call MOM_error(FATAL, "Unsupported WAVE_METHOD encountered in NUOPC cap.")
    endif
  endif

How is MOM6 importing and using waves when the use_waves parameter is not present in the MOM_input_hafs?

[jiandewang]

this parameter needs to be here (false is its default), other wise it will break mpi test (answer change with different PE #) on wcoss2. There is a FMA bug in the code but GFDL haven't figured it out yet.

[binli2337]

@jiandewang The file "MOM_input_hafs" has been updated. Thanks!

[binli2337]

@DeniseWorthen The file "MOM_input_hafs" has been updated for the 2-way ocean wave coupling test. The test name is hafs_regional_storm_following_1nest_atm_ocn_wav_mom6. Thanks!

[DeniseWorthen]

@binli2337 Are you using a new or updated WW3 mod_def for this test? If not, I believe you are exporting all 0s from WW3 for the stokes components. See this line

https://github.com/NOAA-EMC/WW3/blob/8e676278822292a97b2b69da336444ec7d04c06b/model/src/wav_import_export.F90#L808

You need to have the following line in your inp file for WW3 in order to calculate the stokes for export:

&OUTS USSP = 1, IUSSP = 3, STK_WN = 0.04, 0.110, 0.3305 /

How are you testing this? Have you verified non-zero stokes fields sent to OCN?

[binli2337]

@DeniseWorthen Yes, the model definition file has been updated with the stokes drift components. The updated file is from my input directory on Hera. You can verify the stokes drift fields from the mediator history file.

[DeniseWorthen]

@binli2337 Thanks, I found the mod_def (we need to be careful and commit the updated inp file too). But I still don't understand why the changes are necessary in WW3 or MOM6. I ran the mom6 RT w/ only your changes to CMEPS (to add the field exchanges). All the stokes drifts components are already 0.0 in the areas where there is no overlap.

[binli2337]

@DeniseWorthen Thank you for identifying some interpolation issues. The issues have been fixed.