Would it be possible to add the capability to allow RUC LSM physics suites to work with internal ice temperature (tiice)

[MichaelLueken]

Description

When chgres_cube was updated to use fractional grids, internal ice temperature (tiice) was added. While updating the SRW App to the hash that introduced fractional grids, the workflow end to end (WE2E) tests that use RAP and HRRR SDFs began failing while attempting to read tiice from the sfc_data file. Since these SDFs use RUC LSM, the number of vertical layers are set as 9, but tiice only has 2 vertical layers.

Solution

Is it possible to add the ability for SDFs that use RUC LSM to read in the tiice field that is generated in the current chgres_cube?

Alternatives

I've reached out to the UFS_UTILS team to see if they could add the ability to generate v1 coldstart surface files. They noted that continued support of v1 coldstart surface files is deprecated and will be going away. Either removing or replacing the RAP and HRRR SDF WE2E tests is also a possibility for the SRW App moving forward.

If RAP and HRRR SDFs are being deprecated, then I can move forward with removing or replacing the RAP and HRRR SDF WE2E tests.

Testing:

No changes have been made to test. Only the SRW App's WE2E tests have been run and all RAP and HRRR SDF tests have failed in the weather-model with the following output:

NetCDF: Start+count exceeds dimension bound: netcdf_read_data_3d: file:INPUT/sfc_data.nc- variable:tiice

Dependent PRs:

This capability would assist the SRW App with ufs-community/ufs-srweather-app/pull/1089, where we need the chgres_cube to accept RRFS ICs and LBCs.