Glacier modifications in NoahMP to address GFSv17 biases

[barlage]

Description of Changes:

Testing for GFSv17 exposed temperature and albedo biases over glacier regions. There were also large differences when compared to GFSv16 (current operational) and ERA5. To address these biases, the following changes are added:

• removal of albedo aging (current approach is probably too aggressive for remote locations like Antarctica and Greenland)
• change snow thermal conductivity to be consistent with that used in non-glacier NoahMP model
• keep the snow depth and density fixed over glacier following a similar approach used in other NWP systems; this includes cold starting glaciers with 2m of snow

Tests Conducted:

• C1152 simulation on 2025-12-02 to test performance over Antarctica
• Regression tests run on ursa

Dependencies:

• Glacier modifications in NoahMP to address GFSv17 biases NOAA-EMC/ufsatm#1010
• Glacier modifications in NoahMP to address GFSv17 biases ufs-weather-model#2886

Documentation:

No documentation changes required

Contributors:

@wzzheng90 @zhichang-guo

[grantfirl]

Any chance that ufs-community/ufs-weather-model#2759 could also be addressed here?

[barlage]

Any chance that ufs-community/ufs-weather-model#2759 could also be addressed here?

@grantfirl There has been some additional divergence from the component model version of noahmp that I didn't want to tie up in this PR, I am planning to follow up with syncing of those codes, so I can address this issue in that effort. does that work for you?

[grantfirl]

Any chance that ufs-community/ufs-weather-model#2759 could also be addressed here?

@grantfirl There has been some additional divergence from the component model version of noahmp that I didn't want to tie up in this PR, I am planning to follow up with syncing of those codes, so I can address this issue in that effort. does that work for you?

@barlage Of course. No pressure, I just recalled the issue and was curious if it was on your radar since this PR is already touching that file.

[grantfirl]

@barlage I understand that this is high priority for the UFS queue from @rhaesung. We'll try to get it near the top.

[barlage]

thanks @grantfirl

[gspetro-NOAA]

On the WM side, testing is complete for PR #2886, and we're ready to begin the merging process for this subcomponent PR.