Update Icepack to #0fa79f8a8c3579, July 29, 2026.

[apcraig]

PR checklist

• Short (1 sentence) summary of your PR:
  Update Icepack to #0fa79f8a8c3579, July 29, 2026.
• Developer(s):
  apcraig
• Suggest PR reviewers from list in the column to the right.
• Please copy the PR test results link or provide a summary of testing completed below.
  Results are bit-for-bit in CICE except alt03 tests which have calc_Tsfc=.false.
  https://github.com/CICE-Consortium/Test-Results/wiki/cice_by_hash_forks#c08108f9c4ce0f4d54ad13ed47523af1c8a86337
• How much do the PR code changes differ from the unmodified code?
  • bit for bit except with calc_Tsfc=.false.
  • different at roundoff level
  • more substantial
• Does this PR create or have dependencies on Icepack or any other models?
  • Yes
  • No
• Does this PR update the Icepack submodule? If so, the Icepack submodule must point to a hash on Icepack's main branch.
  • Yes
  • No
• Does this PR add any new test cases?
  • Yes
  • No
• Is the documentation being updated? ("Documentation" includes information on the wiki or in the .rst files from doc/source/, which are used to create the online technical docs at https://readthedocs.org/projects/cice-consortium-cice/. A test build of the technical docs will be performed as part of the PR testing.)
  • Yes
  • No, does the documentation need to be updated at a later time?
    • Yes
    • No
• Please document the changes in detail, including why the changes are made. This will become part of the PR commit log.

Update Icepack to #0fa79f8a8c3579, July 29, 2026.

• Add conductive flux limiting for vertical thermodynamics when calc_Tsfc=.false. This changes answers when calc_Tsfc=.false.

• Also updates Icepack documentation and derecho ports. These do not impact CICE directly and are bit-for-bit in CICE.

Update forum links in documentation

[dabail10]

Can you also add a fix for issue

[anton-seaice]

• bit for bit except with calc_Tsfc=.false.

CICE-Consortium/Icepack#561 was also not bfb for some BGC cases