Question about region case

[Zh Chen]

Hi everyone, I am using the CLM5.0 in the CESM2.1.3. I'm planning to run a case to assess the performance that I‘ve incorporated parameterization schemes into CLM5.0. The region of the case is the Northern Hemisphere, and the time range is 1901-2014, as determined by the GSWP3v1 data. The following are the steps:

./create_newcase --case HIST_hcru_SP_001 --res hcru_hcru --compset HIST_DATM%GSWP3v1_CLM50%SP_SICE_SOCN_SROF_SGLC_SWAV --compiler intel --mach mycompu --run-unsupported
./xmlchange CLM_FORCE_COLDSTART=on
./xmlchange ATM_DOMAIN_FILE=domain.lnd.NorthHem_0.5x0.5_c231024.nc
./xmlchange LND_DOMAIN_FILE=domain.lnd.NorthHem_0.5x0.5_c231024.nc
./xmlchange RUN_STARTDATE=1901-01-01
./xmlchange STOP_OPTION=ndays
./xmlchange STOP_N=5
./xmlchange DATM_CLMNCEP_YR_START=1901
./xmlchange DATM_CLMNCEP_YR_END=2011
./xmlchange NTASKS=512
./case.setup
./case.build --skip-provenance-check
./case.submit

# user_nl_clm
fsurdat='/public1/inputdata/lnd/clm2/surfdata_map/surfdata_NorthHem_0.5x0.5_16pfts_Irrig_CMIP6_simyr2000_c231024.nc
flanduse_timeseries='/public1/inputdata/lnd/clm2/surfdata_map/landuse.timeseries_NorthHem_hist_16pfts_Irrig_CMIP6_simyr1850-2015_c240102.nc'
hist_empty_htapes = .true.
hist_nhtfrq = -24
hist_mfilt = 365
hist_fincl1 = "Rnet","FSR","FLDS","FIRE","TSOI","PBOT","RAIN","Rainf","H2OSOI","SOILICE","SOILLIQ","H2OSNO","ALBD","FSM","FSM_ICE","INT_SNOW","FSNO"
check_dynpft_consistency = .false.

The case is successful. The flanduse_timeseries, LND_DOMAIN_FILE is from "lnd/clm2/surfdata_map/landuse.timeseries_360x720cru_hist_16pfts_Irrig_CMIP6_simyr1850-2015_c170824.nc", "share/domains/domain.clm/domain.lnd.360x720_cruncep.100429.nc".

I have some questions:

1. The "share/domains/domain.clm/domain.lnd.360x720_cruncep.100429.nc" does not include Antarctica.
2. I am unsure whether the chosen compset and settings are correct, especially the check_dynpft_consistency = .false. My main objective is to assess the performance of CLM5.0 with the newly added parameterization schemes.
3. I don’t find the appropriate finidat in initdata_map for the case, Maybe should i spin-up according to the ug? In initdata_map, the restart file like the clmi.I2000Clm50BgcCrop.2011-01-01.1.9x2.5_gx1v7_gl4_simyr2000_c180715.nc means I can use the file start at 2011-01-01 by setting finidat in user_nl_clm, but these restart file like **0241-01-01.nc I don't know how to use it as a specific STARTDATE, althoug it spin-up 241 times.
4. As the default STARTDATE for the HIST or I1850 compset is set to 1850-01-01. What forcing data could start at 1850 for CLM5.0 offline.

Any assistance would be greatly appreciated. Thanks!

 

[Zh Chen]

The fsurdat is from "lnd/clm2/surfdata_map/surfdata_360x720cru_16pfts_Irrig_CMIP6_simyr2000_c170824.nc"
./xmlchange DATM_CLMNCEP_YR_END=2014

Thanks.

 

[slevis]

1. Seems ok, since you are running in the Northern Hemisphere.
2. Seems correct, since you are starting the simulation and landuse in 1901 while pointing to fsurdat from 2000.
3. Your compset indicates that you are setting up an SP simulation. You could spin this up in about 20 years, so your own spin-up may be the "cleaner" approach. For BGC cases, the spin-up takes much longer. Your experiment will still be "cleaner" if you do the spin-up yourself, since you're not finding an appropriate initial file for your specific case.
4. I don't think that we have DATM files for years prior to 1901. We only have landuse data for those years.

 

[Zh Chen]

1. Seems ok, since you are running in the Northern Hemisphere.
2. Seems correct, since you are starting the simulation and landuse in 1901 while pointing to fsurdat from 2000.
3. Your compset indicates that you are setting up an SP simulation. You could spin this up in about 20 years, so your own spin-up may be the "cleaner" approach. For BGC cases, the spin-up takes much longer. Your experiment will still be "cleaner" if you do the spin-up yourself, since you're not finding an appropriate initial file for your specific case.
4. I don't think that we have DATM files for years prior to 1850. We only have landuse data for those years.

Thank you for your response.
Based on your second answer, I am starting the simulation and landuse in 1901 while pointing to fsurdat from 2000, it seems that my fsurdat file might be incorrect. I'm confused about how to obtain the right fsurdat for my historical simulation from 1901 to 2014. In the fsurdat file that I used, "lnd/clm2/surfdata_map/surfdata_360x720cru_16pfts_Irrig_CMIP6_simyr2000_c170824.nc", the MONTHLY_LAI time is 12, maybe it is not appropriate my historical simulation.
Could you give me some advice? Thanks.

 

[oleson]

In SP mode, the LAI is prescribed as a climatology. So, there are only 12 monthly values that are used for each year of the simulation.

 

[slevis]

A couple more clarifications:
- In transient SP simulations, the model will get the LAI from your fsrudat file and the pct_pft from the landuse timeseries.
- In my previous response, I have corrected part 4 to say 1901 rather than 1850.