Questions about using lai_streams in CLM5

[xiaom]

I want to use a LAI with interannual variability (1980-2020) in the model. From previous posts, I roughly understand that lai_streams can be used to achieve this, but I still have some doubts that I hope you can help me clarify. The compset I am using is FHIST (HIST_CAM60_CLM50%SP_CICE%PRES_DOCN%DOM_MOSART_SGLC_SWAV).

Q1: If I set use_lai_streams = .true., should I set do_transient_crops and do_transient_pfts to .false.?

Q2: The default time range in the LAI streams file is 2001-2013. If I want to use LAI data beyond this time range, do I just need to change the time dimension in this file? Or do I also need to modify some code in SatellitePhenologyMod.F90 to ensure the model reads it correctly?

Q3: The publicly available LAI data is TLAI, which does not have a PFT dimension. I am considering using the PCT_CFT, PCT_CROP, PCT_NAT_PFT, and PCT_NATVEG values from the surfdata to obtain the proportion of each PFT and calculate the LAI value for each PFT in the LAI streams. Is this approach feasible?

 

[slevis]

1) I do not have first-hand experience with "use_lai_streams = .true." but I suspect that the model with tell you if you must change do_transient_crops and do_transient_pfts to .false., so I recommend setting to what you prefer and seeing what the model does.
2) Again, because I do not have first-hand experience with this, I am recommending what I would do in your position:
I would first make sure that I can work with the default file as is. Then I would start making changes (one-at-a-time is best usually) to see what works and what doesn't. It seems likely that changing the file's time dimension will do the trick, so for now I do not recommend modifying code.
3) Sounds feasible. It's not clear to me whether you are suggesting reading the file first and then modifying the LAI in the code, or modifying the LAI in the file. My intuition suggests the former as easier than the latter, because both will require some code modification.