Description of changes

Standardizes a dimension name of output variable time_bounds, as well as attributes for that plus mcdate, mcsec, mdcur, and mscur.

Specific notes

Contributors other than yourself: @phillips-ad, @ekluzek

RTM Issues Fixed:

• Resolves Modify naming and attributes of time variables on history files to be consistent with other CESM components #31 .
• Contributes to CTSM issue Modify naming and attributes of time variables on history files to be consistent with other CESM components CTSM#1693 and CTSM PR Standardize time metadata CTSM#2052.

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.rtm.h0.1850-01-06-00000 {
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" ;

An arbitrarily-chosen CTSM test, ERS_D_Ld5.f10_f10_mg37.I2000Clm50BgcCropRtm.cheyenne_intel.rtm-rtmOnFloodOnEffvelOn, passed bit-for-bit against tag ctsm5.1.dev130, despite the changed metadata.