Running with the irrigation model on (for CLM4.0)

In CLM4.0 irrigation and crop can NOT be used together see bug number 1326 in the models/lnd/clm/doc/KnownBugs file. However, in contrast CLM4.5 irrigation can ONLY be used WITH crop. To turn on irrigation for either CLM4.0 or CLM4.5 we simply add "-irrig on" to CLM_BLDNML_OPTS. Just as in the crop example we also change RUN_TYPE to startup so that we don't use an initial condition file that is incompatible with irrigation.

Example 4-2. Example Irrigation Simulation

> cd scripts
# Note here we do a CLMSP simulation as that is what has been validated
> ./create_newcase -case IRRIG -res f19_g16 -compset I -mach yellowstone_intel
> cd IRRIG
# Append "-irrig" to CLM_BLDNML_OPTS in env_run.xml (you could also use an editor)
> ./xmlchange CLM_BLDNML_OPTS="-irrig" -append
# Change to startup type so uses spunup initial conditions file for irrigation if it exists
# By default the model will do a hybrid startup with an initial condition file
# incompatible with the irrigation surface dataset.
> ./xmlchange RUN_TYPE=startup
> ./cesm_setup
# Now build and run normally
> ./
> ./IRRIG.submit


For CLM4.0 we have only run the irrigation model with CLM4.0-SP (i.e. without the CN model). We recommend that if you want to run the irrigation model with CLM4.0-CN, that you do a spinup as outlined in the examples below. But, more than that you may need to make the adjustments we discuss in the Section called Build-Namelist options that should NOT be exercised: in What is scientifically validated and functional in CLM4.5 in CESM1.2.0?.