Inland basin flow coupling and use land fractions on rivers grid

[DanCopsey]

Pass inland basin flow from the rivers (TRIP) to LFRic via OASIS. To get this to conserve water we need to determine if there is any ocean in each TRIP grid point where there is inland basin flow. Therefore we need to pass land fractions into the standalone-TRIP part of JULES. If there is any ocean then pass the inland basin flow to the ocean (alongside river outflow). If there is no ocean then pass the inland basin flow to soil moisture (via LFRic).

Linked with LFRic apps issue ​lfric_apps:#234
Linked with UM issue ​um:#26
Linked with JULES_docs pull request ​#79

JULES branch = https://github.com/DanCopsey/jules/tree/inland_flow

[james-bruten-mo]

[Automatic Update]

The Code Review deadline for the Spring 2026 has passed. As this issue does not have a linked pull request it has been removed from the milestone. Please review this issue and either select a new milestone or close it as appropriate. Please contact @MetOffice/ssdteam if you think there has been an error.

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