FV nudging module contains endrun calls without messages

[nusbaume]

A recent DiscussCESM forum post presented a situation where a user was getting confused due to the lack of any sort of abort message for an endrun call in src/dynamics/fv/metdata.F90, which is used for specified-dynamics nudging runs. Upon further examination there are several other endrun calls in this module that are also missing any sort of error message.

Thus to avoid user confusion in the future, it would be good to add actual error messages to the endrun calls in that module.

[cacraigucar]

@nusbaume - I am looking at this change, and the endrun commands without any message that I am seeing all have a write to iulog right before them. Looking at the forum post information, the error message was in the atm.log file. Since the log messages are multi-line messages in these cases, would a generic call endrun(subname // ":: ERROR - check atm.log for error message) suffice? @gold2718 - do you have any thoughts?

[nusbaume]

Hi @cacraigucar , I believe the "best" solution would be to create a new string variable, and then have those log messages write to that variable, which can then be sent to both iulog and the endrun call.

However, if you are trying to keep the code modifications to a minimum (and since the FV dycore won't be the workhorse dycore in CAM7) then I am also fine to just have the endrun point the user to the atm log file. Your call!

[cacraigucar]

@nusbaume - Since my misc tag contains over a dozen issues, I am keeping edits to a minimum. Unless @gold2718 vetoes it, I am going to just edit the endrun as I suggested. It's not perfect, but I believe it is a good compromise.

[gold2718]

I would veto it but I think we will also be getting new nudging code soon so we can let it ride this time.