Add a recruitment carbon flux history variable

[JessicaNeedham]

Description:

New recruits are added to vegetation carbon history variables but we don’t count new recruits as part of daily allocation because their fluxes don’t make sense until they have lived a full day. If we want to test that the carbon budget is closed by checking that delta C = (allocation + recruits) - (mortality + turnover) then we need a recruit carbon flux. This is just the total carbon of new recruits that is added every day. I'm actually not sure if this should be a site level variable like the current FATES_RECRUITMENT_PF variable? I think that way it would include recruits that die on their first day. But since those recruits don't make it into the biomass history variables I don't know if we want that...

Collaborators:

Lots of help from @ckoven and @rgknox

Expectation of Answer Changes:

This should be bfb as it only adds a new history variable.

Checklist

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All checklist items must be checked to enable merging this pull request:

Contributor

• The in-code documentation has been updated with descriptive comments
• The documentation has been assessed to determine if updates are necessary

Integrator

• FATES PASS/FAIL regression tests were run
• Evaluation of test results for answer changes was performed and results provided

Documentation

• Technical Note update: no update needed
• User's Guide update: no update needed

Test Results:

CTSM (or) E3SM (specify which) test hash-tag:

CTSM (or) E3SM (specify which) baseline hash-tag:

FATES baseline hash-tag:

Test Output:

Tested with E3SM 93ab10c89 and FATES API 29.

Full results with variables included in each term.

[glemieux]

Regression testing on derecho against fates-sci.1.72.2_api.34.0.0-ctsm5.1.dev173 are complete with all expected tests passing b4b including expected FIELDLIST diffs due to the new history variable. Note that there were some expected failures due to current issues that aren't listed in the "expected failure" list currently:

• Non-serial versions of tests using 5x5_amazon failing RUN ESCOMP/CTSM#2423
• Hydro failures waiting on Small number protections to CCH water transfer functions #1164 to come in

That said, this is ready to integrate.