questions about grazing in CLM5

[liliyao]

Hi,

I have a question on the grazing rate on the land use timeseries files for different SSP-RCP scenarios from NCAR inputdata website, e.g.,

https://svn-ccsm-inputdata.cgd.ucar.edu/trunk/inputdata/lnd/clm2/surfdata_map/landuse.timeseries_0.9x1.25_SSP5-8.5_78pfts_CMIP6_simyr1850-2100_c181209.nc

The grazing rate is -9999 on the land and 0 on the ocean. And the values do not change with time. I am curious why the grazing rate is always -9999 and 0, is it because grazing is not enabled in CLM5?

Another related questions:

1. can I turn off the grazing through the namelist item?
2. Based on my reading of src/biogeochem/dynHarvestMod.F90, "do_harvest=.false." is used to turn off only the wood harvest, it cannot turn off the grazing or crop harvest. Is it correct?

Thank you very much!

 

[oleson]

Right, there is no grazing in CLM5. do_harvest only turns the wood harvest on and off.

 

[liliyao]

Thank you for the clarification! May I ask if there is any special reason to include the grazing rate in the surface data and land use timeseries file even though CLM5 actually does not model grazing?

 

[oleson]

I believe it is or was a placeholder for future development.

 

[liliyao]

Thanks!