Linear and adjoint boundary layer physics

[tom-j-h]

PR Summary

Sci/Tech Reviewer: @cjohnson-pi
Code Reviewer: @mo-marqh

• linked https://github.com/JCSDA-internal/lfric-jedi/pull/1210

This development is described on an old trac ticket: https://code.metoffice.gov.uk/trac/lfric_apps/ticket/682. This includes many links to the details of the scheme, as well as plots of results. In particular, https://wwwspice/~tim.payne/docs/4D-Var/PF/TL_BL_2025/TL_BL_2025.html has links to relevant VSDP documents.

Development was done by Tim Payne - I am simply taking the old fcm branch and creating this GitHub PR.

• is blocked-by C224 adjoint tests in jelf #163
• closes Linear and adjoint boundary layer physics scheme #129

PLEASE NOTE - this is a follow-on to #163. The branch was created from #163's branch in my fork, but I can't make a PR into that branch because then I would be stuck in my fork. So, to look at the actual changes relevant to this PR alone, look at the diff of this branch with #161's branch: tom-j-h/lfric_apps@jelf_C224_adjoint_tests...tom-j-h:lfric_apps:tlad_boundary_layer

PLEASE ALSO NOTE - #163 is blocked by #161 which is blocked by #156 which relies on MetOffice/lfric_core#227, so when testing, I used this Core branch.

The change includes new files to be added to BIG_DATA_DIR - see paths to files in /data/users/tim.payne/ in changes. Essentially it is just:
/data/users/tim.payne/lfric_apps/files/final_ls_with_land.nc (on SPICE)
/data/users/tim.payne/lfric_apps/files/final_2021060200-2021060207.nc (on EX, for weekly C224 test)

Also need KGO update for this weekly test: https://cylchub/services/cylc-review/taskjobs/tom.hill/?suite=tlad_boundary_layer-linear_model_ex1a_weekly%2Frun3

Test branch: https://github.com/tom-j-h/lfric_apps/tree/tlad_boundary_layer-test

Code Quality Checklist

• I have performed a self-review of my own code
• My code follows the project's style guidelines
• Comments have been included that aid understanding and enhance the readability of the code
• My changes generate no new warnings
• All automated checks in the CI pipeline have completed successfully

Testing

• I have tested this change locally, using the LFRic Core rose-stem suite
• If required (e.g. API changes) I have also run the LFRic Apps test suite using this branch
• If any tests fail (rose-stem or CI) the reason is understood and acceptable (e.g. kgo changes)
• I have added tests to cover new functionality as appropriate (e.g. system tests, unit tests, etc.)
• Any new tests have been assigned an appropriate amount of compute resource and have been allocated to an appropriate testing group (i.e. the developer tests are for jobs which use a small amount of compute resource and complete in a matter of minutes)

trac.log

Test Suite Results - lfric_apps - tlad_boundary_layer-developer/run20

Suite Information

Item	Value
Suite Name	tlad_boundary_layer-developer/run20
Suite User	tom.hill
Workflow Start	2026-01-29T19:22:52
Groups Run	developer

Dependency	Reference	Main Like
casim	MetOffice/casim@2025.12.1	True
jules	MetOffice/jules@2025.12.1	True
lfric_apps	tom-j-h/lfric_apps@tlad_boundary_layer-test	False
lfric_core	MetOffice/lfric_core@bbb3d8a	True
moci	MetOffice/moci@2025.12.1	True
SimSys_Scripts	MetOffice/SimSys_Scripts@2025.12.1	True
socrates	MetOffice/socrates@2025.12.1	True
socrates-spectral	MetOffice/socrates-spectral@2025.12.1	True
ukca	MetOffice/ukca@2025.12.1	True

Task Information

❌ failed tasks - 12

Task	State
check_jedi_lfric_tests_nwp_gal9-C12_MG_azspice_gnu_fast-debug-64bit	failed
check_jedi_lfric_tests_nwp_gal9-C12_MG_ex1a_cce_fast-debug-64bit	failed
check_jedi_lfric_tests_runge-kutta-C12_azspice_gnu_fast-debug-64bit	failed
check_jedi_lfric_tests_runge-kutta-C12_azspice_gnu_full-debug-64bit	failed
check_jedi_lfric_tests_runge-kutta-C12_ex1a_cce_fast-debug-64bit	failed
check_jedi_lfric_tests_tlm_forecast_tl_nwp_gal9-C12_MG_azspice_gnu_fast-debug-64bit	failed
check_jedi_lfric_tests_tlm_forecast_tl_nwp_gal9-C12_MG_ex1a_cce_fast-debug-64bit	failed
check_linear_model_nwp_gal9-C12_MG_azspice_gnu_fast-debug-64bit	failed
check_linear_model_nwp_gal9-C12_MG_ex1a_gnu_fast-debug-64bit	failed
check_linear_model_nwp_gal9_random-C12_MG_azspice_gnu_fast-debug-64bit	failed
check_linear_model_nwp_gal9_random-C12_MG_ex1a_gnu_fast-debug-64bit	failed
kgo_groups_checker	failed

✅ succeeded tasks - 1099

⌛ waiting tasks - 2

Task	State
housekeep_azspice	waiting
housekeep_ex1a	waiting

Security Considerations

• I have reviewed my changes for potential security issues
• Sensitive data is properly handled (if applicable)
• Authentication and authorisation are properly implemented (if applicable)

Performance Impact

• Performance of the code has been considered and, if applicable, suitable performance measurements have been conducted

AI Assistance and Attribution

• Some of the content of this change has been produced with the assistance of Generative AI tool name (e.g., Met Office Github Copilot Enterprise, Github Copilot Personal, ChatGPT GPT-4, etc) and I have followed the Simulation Systems AI policy (including attribution labels)

Documentation

• Where appropriate I have updated documentation related to this change and confirmed that it builds correctly

PSyclone Approval

• If you have edited any PSyclone-related code (e.g. PSyKAl-lite, Kernel interface, optimisation scripts, LFRic data structure code) then please contact the TCD Team

Sci/Tech Review

• I understand this area of code and the changes being added
• The proposed changes correspond to the pull request description
• Documentation is sufficient (do documentation papers need updating)
• Sufficient testing has been completed

(Please alert the code reviewer via a tag when you have approved the SR)

Code Review

• All dependencies have been resolved
• Related Issues have been properly linked and addressed
• CLA compliance has been confirmed
• Code quality standards have been met
• Tests are adequate and have passed
• Documentation is complete and accurate
• Security considerations have been addressed
• Performance impact is acceptable

[DrTVockerodtMO]

Thank you Tom for consolidating these changes, I appreciate it's quite a large task. I do have some changes that I would like addressed please.

[DrTVockerodtMO]

Thank you for making the changes, looks good to me!

[tom-j-h]

Having problems with the linear integration tests since merging in changes from #170. Working on it now. Once sorted that will be it.

[tom-j-h]

Having problems with the linear integration tests since merging in changes from #170. Working on it now. Once sorted that will be it.

I'm really having trouble understanding this failure. I think @cjohnson-pi will be able to help but is on leave today, back Monday. Sorry to have to hold things up @mo-marqh @jennyhickson

[tom-j-h]

Issue mentioned above now fixed. I misinterpreted what the failed test was telling me. Fix was just to include a switch that doesn't set up the land fraction field when it's not needed. Now ready for Code Review.

[mo-marqh]

this change proposal meets coding standards, is well defined and passed sci/tech review.

macros are run and KGOs updated to enable all and weekly tests

approved for main

[ss421]

For JEDI, we need to fix a couple of the example configurations so perhaps these could be updated with that? @tom-j-h - what is the correct path?

@DanStoneMO is doing that work so could add the correct path?

[ss421]

I know that this has been merged but I wonder if this should be updated to LFRic BIGDATA before the release?

[tom-j-h]

Yes, these should've been changed along with the rose configs. @mo-marqh could this be hotfixed?

[mo-marqh]

#295 to fixup

[ss421]

Here also?

[tom-j-h]

For JEDI, we need to fix a couple of the example configurations so perhaps these could be updated with that? @tom-j-h - what is the correct path?

@DanStoneMO is doing that work so could add the correct path?

I believe the apps run there are forecast and forecast_pseudo, but those example configurations haven't been updated by this PR or earlier ones (since they don't run the TLM).

[ss421]

For JEDI, we need to fix a couple of the example configurations so perhaps these could be updated with that? @tom-j-h - what is the correct path?
@DanStoneMO is doing that work so could add the correct path?

I believe the apps run there are forecast and forecast_pseudo, but those example configurations haven't been updated by this PR or earlier ones (since they don't run the TLM).

Looks like its been fixed by another PR. Was just suggesting that they are updated while Dan was updating other configs but that is no longer needed :-)