ctsm5.3.021: Standardize time metadata (we will mark this as the release tag for ctsm5.3)

[samsrabin]

Description of changes

Standardizes a dimension name of output variable time_bounds (from hist_interval to nbnd), as well as attributes for that plus mcdate, mcsec, mdcur, and mscur.

Specific notes

Contributors other than yourself: @billsacks, @ekluzek

CTSM Issues Fixed: Resolves #1693.
Fixes #2923
Resolves ESCOMP/MOSART#66
Resolves ESCOMP/RTM#35

Are answers expected to change (and if so in what way)? No.

Any User Interface Changes (namelist or namelist defaults changes)? No.

Testing performed

New metadata in a history file from a short test:

netcdf standardize-time-metadata_rtm.clm2.h0.1850-01-01-00000 {
dimensions:
...
    nbnd = 2 ;
...
variables:
...
    int mcdate(time) ;
        ...
        mcdate:calendar = "noleap" ;
    int mcsec(time) ;
        ...
        mcsec:calendar = "noleap" ;
    int mdcur(time) ;
        ...
        mdcur:calendar = "noleap" ;
    int mscur(time) ;
        ...
        mscur:calendar = "noleap" ;
...
    double time_bounds(time, nbnd) ;
        time_bounds:long_name = "time interval endpoints" ;
        time_bounds:units = "days since 1850-01-01 00:00:00" ;
        time_bounds:calendar = "noleap" ;

All aux_clm tests pass bit-for-bit against ctsm5.1.dev131, except for expected failures.

[samsrabin]

Marked as blocked:dependency because, at the moment, Externals.cfg points to branches of my personal MOSART (issue ESCOMP/MOSART#53) and RTM (issue ESCOMP/RTM#31) forks that contain the same changes. I haven't yet submitted those as pull requests, because I first wanted to see if any more testing is requested.

UPDATE
PRs ESCOMP/MOSART#66 and ESCOMP/RTM#35

[samsrabin]

From CTSM software engineering meeting today: This doesn't need to wait on other time-related PRs. It can come in as soon as the relevant externals are updated (and Externals.cfg here is changed to point to them).

[slevis-lmwg]

BEFORE MAKING THE RTM/MOSART TAGS FOR THIS PR...

• Make the same or equivalent change as eeedbc6 to the corresponding rtm/mosart files.

• Bring Erik's bug-fix from mosart1.1.07: Fix Nag compiler error, a few small changes, and convert ChangeLog to markdown MOSART#112 also to rtm.

• Resolve mosart/cpl BASELINE DIFFs discussed initially here
  by replacing the if-statement in commit 692d183 with a comment, as explained in ctsl%rof_to_glc needs to be set before fldlist_add calls adding the Fgrg_rof? fields is done MOSART#103 (comment).

• All of the above will be done in the mosart1.1.08 and rtm1_0_85 tags

• Decide if this is planned to be the ctsm5.3 release tag and if so the following apply:

  • Erik: Bring in the whatsnew in ctsm5.3 PR on b4b-dev
  • Make sure b4b-dev is brought in by this point, currently planned as ctsm5.3.020
  • Finalize the What'sNew in CTSM5.3 document listed below.
  • Update WhatsNew as per this document: https://docs.google.com/document/d/12KS5eU6gIaicZ4hJhgZWmys8fLLl5IkxwC_Pi76FuHw/edit?tab=t.0
  • Do things in: https://github.com/ESCOMP/CTSM/wiki/Minor-Version-Update-Protocols
  • Do some testing for mksurfdata_esmf to make sure it's still working and will be ready for ctsm5.4 when the CMIP7 datasets come down.
  • Decide who should review what part of changes from the ctsm5.3.0 tag

[ekluzek]

From a skim of the changes I don't see issues to comment on. The changes of ctsm5.3.018 and ctsm5.3.019 are included here, so a lot of differences will go away and it will be easier to see what's going on.

@samsrabin since you did this work, it might be good have you go over some of it with @slevis-lmwg and I. I know it was forever ago and you don't remember a lot of it, but it'll probably work fine to have all of us look at it together. So let's tentatively plan on doing that next week if possible.

At this point the python unit testing and the RXCROP tests should all work and we should make sure they do. This could be to just run ctsm_sci as mentioned just below.

If this is the tag that we are going to mark as the ctsm5.3 release tag, we should also run fates and ctsm_sci test lists. And we should make sure b4b-dev has come in by this tag. And we should make sure the WhatsNewInCtsm5.3 file is updated with the latest we have for the document that talks about it.

[slevis-lmwg]

derecho testing prior to updating .gitmodules to mosart1.1.08 and rtm1_0_85 in ce7f7b2:

PASS ./build-namelist_test.pl
PASS black and lint, though the latter gave 2 warnings
PASS ./run_ctsm_py_tests

[slevis-lmwg]

Note to self: Consider initiating further testing, but perform final testing after updating to ctsm5.3.020.