EAMxx: introducing Reproducible Climate Statistics test

[mahf708]

Introducing RCS (and removing MVK) to ATM.

Highlights:

• perturb test mod for creating necessary perturbation
• RCS system test with rcs_perts (manipulate perturbation) and est_stats for statistical testing
  • rcs_stats can be triggered from the command line too (some details in rcs_stats were generated by bot)
  • note a limitation in cice (in eam and cice buildnml, ntasks are wrong in multi-deriver multi-instance setup #7788)
• automatically generated docs

docs: https://docs.e3sm.org/E3SM/pr-preview/pr-7789/EAMxx/user/multi-instance-rcs

cocreated with bots

[BFB]

[github-actions]

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[whannah1]

Minor quibble - the "EST" terminology is redundant if we refer to an "EST test" - so how about we call it something like "ENS" for "ENsemble Statistics" test?

[jgfouca]

Looks great! Just some style comments

[Copilot]

Pull Request Overview

This pull request replaces the MVK (Multivariate Kolmogorov-Smirnov) testing system with a new RCS (Reproducible Climate Statistics) system for NBFB (Not-Bit-For-Bit) testing in EAMxx. The RCS system provides a more comprehensive statistical testing framework with multiple test types and enhanced configurability.

Key changes include:

• Introduction of RCS system test with comprehensive statistical testing capabilities
• New perturbation test mod for creating ensemble perturbations
• Automated documentation generation for the RCS system

Reviewed Changes

Copilot reviewed 16 out of 18 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
components/eamxx/mkdocs.yml	Updated documentation link from MVK to RCS
components/eamxx/docs/user/multi-instance-rcs.md	New comprehensive documentation for RCS system
components/eamxx/docs/user/multi-instance-mvk.md	Removed old MVK documentation
components/eamxx/cime_config/testdefs/testmods_dirs/eamxx/perturb/*	New perturbation testmod for RCS ensemble setup
components/eamxx/cime_config/testdefs/testmods_dirs/eamxx/mvkpert/*	Removed old MVK perturbation files
components/eamxx/cime_config/config_tests.xml	Updated test configuration from MVKxx to RCS
components/eamxx/cime_config/SystemTests/rcs_stats.py	New comprehensive statistical testing framework
components/eamxx/cime_config/SystemTests/rcs_perts.py	New perturbation utilities for RCS
components/eamxx/cime_config/SystemTests/rcs.py	New RCS system test implementation
components/eamxx/cime_config/SystemTests/mvkxx.py	Removed old MVK system test
components/eamxx/cime_config/SystemTests/ksxx*	Removed old KS test files

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[AaronDonahue]

@mahf708 , just wanted to check in on the status of this PR

[mahf708]

I'd like to address comments above by Jim, Luca, and Noel. I will do that soon, hopefully before Monday.

[Copilot]

Pull Request Overview

Copilot reviewed 16 out of 18 changed files in this pull request and generated 2 comments.

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[mahf708]

@AaronDonahue, this is ready for integration as-is.

It would be nice to add some tests to test.py; let's see what @ndkeen recommends. That can be done either here or in a follow-up PR. I'd like @jgfouca, @bartgol, and @ndkeen to take one last look before integration. Thanks!

[mahf708]

@ndkeen note that changing HIST_OPTION will make the test fail by default. There's a workaround to override the hist archive, etc., but I thought I'd rather avoid that potential rabbit hole for now. We are disallowing useless restarts though, so that's a plus!

[mahf708]

For Jim, only this commit should be reviewed: cd06159

[jgfouca]

Much better! Just one minor thing

[mahf708]

thanks @ndkeen

@bartgol, whenever you have time, this can go in. It's an eamxx-only PR, and shouldn't affect anything but a new lowly abject test :D