Calculating Lamb weathertypes for CMIP5, CMIP6, SMILES and EURO-CORDEX

[thomaskroi1996]

Description

Hello everyone!

At the Wegener Center in Graz, Austria, we have been doing some research with Lamb Weathertypes for quite some while now, and recently started developing a diagnostic for ESMValTool to make things easier, and potentially be of use for others!

The features are:

• Calculate the 27 Lamb Weathertypes over a region specified in the corresponding recipe
• Plot means, anomalies as well as standard deviations for those weathertypes for psl, tas and prcp
• Combining the weathertypes based on precipitation patterns over an area specified in the corresponding recipe as done here: https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2020JD032824 (Table 2)
• Create the same plots for those combined weathertypes

The weathertypes are calculated for ERA5 and model data, and the precipitation data for correlation calculations are taken from ERA5 and E-OBS.

The branch we are working on is called weathertyping_wegc.

We are happy to discuss this project with the community, get some feedback and features you would like to see!

If this PR seems like a deja vu, it is probably because it is! Last year I worked on this project, and since then not much has happened, and the old PR got outdated! I decided to open a new PR and already have the first commits be much cleaner! Hope that is okay, the old one is closed now, here is the link for reference! #3691

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Checklist

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New or updated recipe/diagnostic

• 🧪 Recipe runs successfully
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• 🧪 Figure(s) and data look as expected from literature
• 🛠 Provenance information has been added

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[valeriupredoi]

hi @thomaskroi1996 and very many thanks for contributing 🍻 Please ping me here when this is ready for review, I shall do a technical reviwe, then we'll look for a scientific reviewer. Cheers!

[bouweandela]

If you run into any issues with CORDEX data, we (NLeSC and BSC) may have some time available to help you as part of WP2 of the ESO4clima project, where we're working on improving CORDEX support. You can see some of the current issues in ESO4clima WP2 and @sloosvel has already created an example recipe using CORDEX data in #4199 that may be useful for inspiration.

[thomaskroi1996]

@bettina-gier hey :) hope you had nice holidays and wish you a happy new year!

I have solved the issues and uploaded the output here:
https://drive.google.com/drive/folders/1XsxMRXGD9AraWswjpAFgiTRP6gRIMIFG?usp=drive_link

thank you!

[bettina-gier]

Happy New Year, sorry for the late reply!

Heatmaps look good, but I'm not sure if this is a rerun, both the main_log and the log for the diagnostic says run failed and there's no provenance for any of the plots - those get made when running the full recipe, not just the rerun. So sorry to ask, but can you do a full run without rerun to check that all of the provenance works? =D

I'll try to run it locally as well with the smaller ERA5 timeseries we have data for.

[thomaskroi1996]

thank you, now worries!

new year, same old mistakes i make :D i sent you an e-mail with the output! thanks so much!

[bettina-gier]

The work output files look good, so do the heatmaps and mean plots, but I don't see provenance for the seasonal_occurrence plots, can you double check that? Afterwards it's ready to go for me

[thomaskroi1996]

@bettina-gier oh, i had a mismatch in the output for provenance and plot names for the seasonal occurrence! now it works!

[bettina-gier]

Nice, the new output looks good, all provenance there!

@valeriupredoi Do we want to merge this as-is or should we shorten the timeseries to what we have at Levante so the recipe won't fail in the recipe test workflow?

[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]

Thanks for your contribution @thomaskroi1996, and thank you to the reviewers @bettina-gier and @valeriupredoi ! Merging this now 🚀

[thomaskroi1996]

@valeriupredoi @bettina-gier @schlunma thanks again everyone for the help, appreciate it a lot! :)

[valeriupredoi]

many thanks for merging @schlunma - I was literally about to hit the magic button myself 😁 Great stuff @thomaskroi1996 and @bettina-gier 🍻