Coordination between HLM and FATES

[wwieder]

We had an interesting discussion at the CTSM SE meeting today about how to coordinate development that are occurring in the big leaf model that may also be helpful for FATES to consider. We noted there's not really a good way to coordinate this exchange beyond informal communication (e.g. between @ekluzek and @glemieux ).

Specifically CTSM has a new PR that clearly improves roughness length. As implemented this PR will not affect FATES, BUT in the meeting we wondered:

1. How roughness length is calculated in FATES?
2. If there may be worth adapting some of this work to FATES? and If yes to 2,
3. How / who could even take this on? (we, at NCAR don't have someone who can take this on now).

More broadly, this sparked a discussion on how to handle developments that come in for the big leaf model that may be worth building into FATES. Eventually @dlawrenncar noted we hope to drop support for the big leaf model, but @jkshuman emphasized we're not there yet (nor are the CTSM SE meetings the place to have this conversation).

[jkshuman]

@wwieder I would recommend opening a specific issue FATES issue to bring together this development on surface roughness. It may be that it is open and closed quickly, or it will stay open until someone can address it.
I also want to clarify that I support a full transition to FATES, but I don't think the CTSM SE meeting is the place to make this decision. It is not a quick switch, and I recognize this needs to be discussed with a larger group.