Adding fix for ORAS5

[jmalles]

Description

Fix for ORAS5. It includes the option to make the 'irregular' (2d) grid 'unstructured' (1d) and UGRID-compliant. To do so, one needs to add the extra facet 'make_unstructured: true' and/or 'ugrid: true' in the recipe.

The mesh description ('horizontal_grid' in the recipe) needs to be read from a file (oras5_mesh.zip), which is based on a file that can be downloaded here. Since ORAS5 data is on the ORCA025 (Arakawa-C grid), there are different mesh files for tracers (T), and zonal/meridional velocities (u/v).

An example recipe for ORAS5 can be found here.

Some already downloaded data are stored here:
/work/bd1083/b380216/extraobsraw/Tier2/ORAS5/single_level
/work/bd1083/b380216/extraobsraw/Tier2/ORAS5/all_levels
/work/bd1083/b382555/extraobsraw/Tier2/ORAS5/single_level
/work/bd1083/b382555/extraobsraw/Tier2/ORAS5/all_levels

(for 3D data in all_levels so far usually only short time periods are downloaded, due to their size)

The grid files are also stored on Levante:
/work/bd0854/b382555/extraobsraw/Tier2/ORAS5/grids

Link to documentation: https://esmvaltool--2422.org.readthedocs.build/projects/ESMValCore/en/2422/quickstart/find_data.html#oras5

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 96.22%. Comparing base (a0af0c4) to head (c33838b).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2422      +/-   ##
==========================================
+ Coverage   96.18%   96.22%   +0.04%     
==========================================
  Files         271      272       +1     
  Lines       15911    16087     +176     
==========================================
+ Hits        15304    15480     +176     
  Misses        607      607              

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[bettina-gier]

Tried with the example recipe and it looks good, output seems as expected. Fast look through the code looks good. I'll do a more detailed review when I have more time.

[schlunma]

Hi @jmalles, thanks for contributing!

To start the review process and finalize this, we need tests (see e.g., here) and some documentation (see e.g, here). Thanks!!

[schlunma]

Hello, this pull request has been marked with the v2.14.0 milestone. The release of version 2.14.0 is currently scheduled for February 2026. To get this into the new release, it would be great to get this merged by the end of January.

If you won't be able to finish this in time, don't worry - just unassign the milestone v2.14.0. If you need any support, ping myself (@schlunma; the release manager for v2.14.0) or the @ESMValGroup/technical-lead-development-team. Please note that I won't be available until the beginning of February, though.

[schlunma]

I am sorry, it looks like this pull request won't make it into v2.14.0. If there are strong objections, please let me know. Moving this to v2.15.0.

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you all sign our Contributor License Agreement before we can accept your contribution.
2 out of 3 committers have signed the CLA.

✅ katjaweigel
✅ jmalles
❌ Jan-Hendrik Malles

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[rbeucher]

Hi all, a quick note for the ESMValCore v2.15.0 release: the planned code freeze date is 19 June 2026.

This PR is currently included in the v2.15.0 milestone. Could you please confirm whether it is still intended for this release and what needs to happen before it can be merged?

@flicj191 tagging you for release planning visibility.

[jmalles]

Hello, I will try to get the code coverage to 100% today or tomorrow. Then someone would need to review it, I suppose.

[bettina-gier]

@ghossh Hey Supriyo, Jan has updated the tests now to increase the coverage. Can you have a look and do a review please? <3

[ghossh]

Hi @bettina-gier , I'm going on holiday after today and coming back on 28th Jun. I'll take a look afterward.

[bettina-gier]

ah nvm then, that's after the core feature freeze where we want to have this in. I'll see if I can do it next week instead then..