Signed the CLA.

[alasdair-roy]

Closes #97

To be completed prior to review request and updated as required during the review process.

If the answer to an item on the list is not applicable, feel free to replace the checkbox with 'N/A' to give extra clarity.

All developers are reminded to follow the ancil working practices

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Branch

Related branches (e.g. ug-ancillary-file-science):

[please link any related branches here]

UG-ANTS rose stem logs

https://cylchub/services/cylc-review/taskjobs/alasdair.roy/?suite=UGANTS_97%2Frun1

ug-ancillary-file-science rose stem logs

[please enter the workflow name here as it has been run e.g. ug-ancillary-file-science/run1]

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Testing

For core UG-ANTS only tests, the bare minimum that will be accepted is the group=unittests but many, if not most, changes will need to test other groups to ensure they meet reviewer expectations. In general, it should be possible and is advised to run the group=all group prior to review submission as this will catch any consequential issues. Additionally you must run the ug-ancillary-file-science tests, pointing at your branch, with group=all to capture any behaviour changes affecting Science codes.

If your change will alter existing science results, you will need to seek appropriate Scientific validation and confirm that the model has been initialised with your new development. Inspecting a change in xconv/pyplot/visualiser of choice is not sufficient to demonstrate the model can be initialised from your file.

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Impact of change

• This will maintain results for UG-ANTS cylc vip ./rose-stem -z group=all tests
• This will this maintain results for ug-ancillary-file-science cylc vip ./rose-stem -z group=all tests
• If this change adds a new capability, evidence has been supplied to show testing of ancillary generation across different resolutions e.g. For global ancillary generation capabilities for use in NWP C896 is expected to have been tested
• This change has significantly impacted required resources (runtime and memory) in existing ancillary generation (if yes, give details)
• This change alters existing ancils

Add further comments/details for your reviewers here on the impacts of the change......

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Approvals for this change

• I have approval from the UG-ANTS core development team for these changes

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New functionality further testing

• If adding new functionality to existing codes, I confirm that the new code doesn't change results when it is switched off and ''works'' when switched on
• Unittests have been added
• Rose stem tests have been added for any new functionality
• I have not encountered any failures in my rose-stem output(s)
  These tasks must succeed for your ticket to pass review.
• I have remembered to run the code style check tasks/tools

Add details of any further testing here.

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Other

• I have read the Contributor Licence Agreement
• I have added my name and affiliation to the Contributors list if I am not already on there in this PR.
• The ticket labels, milestones, etc. are correct
• Links to all related tickets have been provided in the ticket description
• I have requested a code reviewer
• Source data has been added or changed - please include a link to the license

I confirm that all code is my own and that my contributions are not subject to copyright or license restrictions (see Contributor Licence Agreement).	Alasdair Roy
I confirm I have not knowingly violated intellectual property rights (IPR) and have taken sensible measures to prevent doing so, including appropriate attribution for usage of Generative AI. I confirm that this work is my own, and I understand that it is my responsibility to ensure I am not violating others’ IPR. This includes taking reasonable steps to ensure that all tools used while creating this contribution did not infringe IPR.	Alasdair Roy

Please add any further notes here. If Generative AI tools have been used, a brief summary (e.g. "Github copilot used to add extra unittests") should be provided.

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Rose stem logs

Please copy in the contents of your trac_status.log file(s) below (found in the cylc-run directory for your rose stem run) to your rose-stem testing here. Note: if your changes lead to a change in answers, you must run cylc vip ./rose-stem -z group=all to help ensure all affected configurations has been flagged up.

Thu 20 Aug 10:24:10 BST 2026 Git status: [ "" ] Commit: 658ed03

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Test Results - Summary

tasks	total
succeeded	65

Test Results - Detail

task	status
install_cold	succeeded
ancil_regrid_mesh_to_grid_use_input_weights_nearest	succeeded
ancil_regrid_mesh_to_grid_output_weights_conservative	succeeded
ancil_regrid_grid_to_mesh_conservative	succeeded
ancil_regrid_mesh_to_grid_output_weights_bilinear	succeeded
ancil_regrid_grid_to_mesh_use_input_weights_conservative	succeeded
ancil_regrid_grid_to_mesh_use_input_weights_nearest	succeeded
ancil_split_by_latitude_grid_to_mesh	succeeded
ancil_regrid_grid_to_mesh_use_input_weights_bilinear	succeeded
ancil_extract_mesh	succeeded
ancil_generate_mask_sea	succeeded
ancil_regrid_mesh_to_grid_use_input_weights_bilinear	succeeded
ancil_regrid_mesh_to_mesh_bilinear_tolerance	succeeded
ancil_regrid_grid_to_mesh_output_weights_bilinear	succeeded
ancil_generate_mask_land	succeeded
ancil_split_by_latitude_mesh_to_grid	succeeded
build_docs	succeeded
ancil_regrid_mesh_to_grid_nearest	succeeded
ancil_ugrid_to_XIOS	succeeded
ancil_ugrid_to_XIOS_single	succeeded
ancil_regrid_grid_to_mesh_bilinear_tolerance	succeeded
ruff	succeeded
ancil_fill_missing_points_no_target_mask	succeeded
ancil_fill_missing_points_with_target_mask	succeeded
ancil_regrid_mesh_to_mesh_nearest	succeeded
ancil_regrid_mesh_to_grid_use_input_weights_conservative	succeeded
ancil_regrid_mesh_to_mesh_conservative	succeeded
ancil_regrid_grid_to_mesh_conservative_tolerance	succeeded
ancil_regrid_grid_to_mesh_output_weights_nearest	succeeded
ancil_regrid_mesh_to_grid_bilinear	succeeded
ancil_regrid_grid_to_mesh_nearest	succeeded
ancil_regrid_mesh_to_grid_output_weights_nearest	succeeded
ancil_regrid_grid_to_mesh_bilinear	succeeded
ancil_regrid_mesh_to_mesh_conservative_tolerance	succeeded
ancil_regrid_mesh_to_mesh_bilinear	succeeded
black	succeeded
unittests	succeeded
ancil_regrid_mesh_to_grid_conservative	succeeded
ancil_regrid_grid_to_mesh_output_weights_conservative	succeeded
rose_ana_extract_mesh	succeeded
rose_ana_fill_missing_points	succeeded
rose_ana_generate_mask	succeeded
rose_ana_ugrid_to_XIOS	succeeded
rose_ana_regrid_grid_to_mesh	succeeded
rose_ana_regrid_mesh_to_grid	succeeded
rose_ana_regrid_mesh_to_mesh	succeeded
ancil_band_regrid_grid_to_mesh_bilinear_tolerance	succeeded
ancil_band_regrid_grid_to_mesh_conservative	succeeded
ancil_band_regrid_grid_to_mesh_bilinear	succeeded
ancil_band_regrid_grid_to_mesh_nearest	succeeded
ancil_band_regrid_grid_to_mesh_conservative_tolerance	succeeded
ancil_band_regrid_mesh_to_grid_conservative	succeeded
ancil_band_regrid_mesh_to_grid_bilinear	succeeded
ancil_band_regrid_mesh_to_grid_nearest	succeeded
linkcheck	succeeded
ancil_recombine_mesh_bands_nearest	succeeded
ancil_recombine_mesh_bands_conservative	succeeded
ancil_recombine_mesh_bands_bilinear_tolerance	succeeded
ancil_recombine_grid_bands_nearest	succeeded
ancil_recombine_mesh_bands_bilinear	succeeded
ancil_recombine_grid_bands_bilinear	succeeded
ancil_recombine_grid_bands_conservative	succeeded
ancil_recombine_mesh_bands_conservative_tolerance	succeeded
rose_ana_band_regrid_mesh_to_grid	succeeded
rose_ana_band_regrid_grid_to_mesh	succeeded

Add trac_status.log contents for ug-ancillary-file-science rose-stem here.