Snow cover fraction for Advancing Arctic Capabilities Programme

[Richard Essery (RichardEssery)]

PR Summary

Sci/Tech Reviewer:
Code Reviewer: R Sharp (@r-sharp)

Option to have a separate surface energy balance for the snow-covered fraction of short vegetation and bare soil tiles

Code Quality Checklist

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• I have performed a self-review of my own code
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  stem suites
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trac.log

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Technical

• JULES Code Owner
• OpenMP
• River Routing
• Rose Stem
• Rose Metadata
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Scientific

• Surface
• Hydrology
• Vegetation
• Veg3 RED Demography
• Biogechemistry
• Biogenic fluxes
• Fire
• Lakes
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• Imogen

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Code Review

• All dependencies have been resolved
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• Security considerations have been addressed
• Performance impact is acceptable

[Helen Johnson (HelenRJohnson)]

Suggested change

	!$OMP PRIVATE( l, n, c, use_tile )
	!$OMP PRIVATE( l, n, c, use_tile, snow_tile )

[Helen Johnson (HelenRJohnson)]

Suggested change

	!$OMP l_elev_land_ice, surft_pts ) &
	!$OMP l_elev_land_ice, surft_pts, i_snow_tile ) &

[Helen Johnson (HelenRJohnson)]

When I ran the LFRic rose-stem test with this JULES branch there were a few tests that failed due to variables not being included in the OMP statement in the tilepts subroutine. I haven't had a chance to run the UM rose-stem tests yet but I imagine that will produce similar complaints. I've added suggestions for the changes I think are needed to get rid of those errors.

[Richard Essery (RichardEssery)]

Hi Helen, I didn't need to/couldn't test OMP declarations in my compilation of JULES, but whatever you need to pass the test should be OK. I would not expect tilepts to be the only place this arises. Richard From: Helen Johnson ***@***.***> Sent: 10 July 2026 13:57 To: MetOffice/jules ***@***.***> Cc: Richard Essery ***@***.***>; Assign ***@***.***> Subject: Re: [MetOffice/jules] Snow cover fraction for Advancing Arctic Capabilities Programme (PR #105) [https://avatars.githubusercontent.com/u/138898055?s=20&v=4]HelenRJohnson left a comment (MetOffice/jules#105)<#105 (comment)> When I ran the LFRic rose-stem test with this JULES branch there were a few tests that failed due to variables not being included in the OMP statement in the tilepts subroutine. I haven't had a chance to run the UM rose-stem tests yet but I imagine that will produce similar complaints. I've added suggestions for the changes I think are needed to get rid of those errors. - Reply to this email directly, view it on GitHub<#105?email_source=notifications&email_token=AC24BEWMB4MQ7NLU732YWAL5EDRZ3A5CNFSNUABFM5UWIORPF5TWS5BNNB2WEL2JONZXKZKDN5WW2ZLOOQXTIOJTGU2TCNRWGUYKM4TFMFZW63VGMFZXG2LHN2SWK5TFNZ2KYZTPN52GK4S7MNWGSY3L#issuecomment-4935516650>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/AC24BETEL2KHXF2R6AUZIWT5EDRZ3AVCNFSNUABGKJSXA33TNF2G64TZHMYTAOBWGUZTENJQGI5US43TOVSTWNBSHA4DIMZWHAYDBILWAI>. Triage notifications, keep track of coding agent tasks and review pull requests on the go with GitHub Mobile for iOS<https://github.com/notifications/mobile/ios/AC24BEV5TKIKIFYDKEFPNXD5EDRZ3A5CNFSNUABFM5UWIORPF5TWS5BNNB2WEL2JONZXKZKDN5WW2ZLOOQXTIOJTGU2TCNRWGUYKM4TFMFZW63VGMFZXG2LHN2SWK5TFNZ2KUZTPN52GK4S7NFXXG> and Android<https://github.com/notifications/mobile/android/AC24BEXX7KP4GJT4XIJXBMD5EDRZ3A5CNFSNUABFM5UWIORPF5TWS5BNNB2WEL2JONZXKZKDN5WW2ZLOOQXTIOJTGU2TCNRWGUYKM4TFMFZW63VGMFZXG2LHN2SWK5TFNZ2K4ZTPN52GK4S7MFXGI4TPNFSA>. Download it today! You are receiving this because you were assigned.Message ID: ***@***.******@***.***>> The University of Edinburgh is a charitable body, registered in Scotland, with registration number SC005336. Is e buidheann carthannais a th' ann an Oilthigh Dh?n ?ideann, cl?raichte an Alba, ?ireamh cl?raidh SC005336.

[Helen Johnson (HelenRJohnson)]

Ah, OK, maybe that was just the first subroutine to fail then, I'll check out a copy of the code then and see how many places need variables adding to OMP statements before the tests pass.