no change in atm_in

[ybj]

Hello everyone, I am currently learning to use CESM2.2 with CAM6, following the CAM6 user guide. 3. Building and Running the atmospheric model within CESM — camdoc documentation

When I added 'co2vmr = 400.e-6' to user_nl_cam as per the guide and run ./preview_namelists, it did not appear in the atm_in file as described in the guide. I am wondering why this is the case. Below are my operations：
/work/software/cesm/2.2.0_openmpi2020/cime/scripts/create_newcase --case ~/ymt/case_cesm2/test_FHIST --compset FHIST --res f09_f09_mg17 --run-unsupported
./xmlchange NTASKS_CPL=-2,NTASKS_ATM=-2,NTASKS_LND=-1,NTASKS_ICE=-1,NTASKS_OCN=-1,NTASKS_ROF=-1,NTASKS_GLC=-1,NTASKS_WAV=-1,NTASKS_IAC=1,NTASKS_ESP=1
./xmlchange ROOTPE_ICE=-1,ROOTPE_OCN=-2

./case_setup

vi user_nl_cam
co2vmr=400.e-6
./preview_namelists
When I executed ./preview_namelists -d, the following appeared in the preview_namelists.log file:

 

[dbailey]

I am going to move this to the CAM forum, however, I think the issue is that this also needs to be changed in env_run.xml. Try doing:

./xmlchange CCSM_CO2_PPMV=400.

 

[peverley]

Hi, It looks like the case you are running has a default flbc_file set

I found a related answer here: [Question] Different namelist for CO2 concentration in F compset and B compset ?

You are not able to override [the flbc_file] by setting co2vmr in your user_nl_cam file. If you want to do that, you will need to create your own use_case file. If you create your own use case, we also recommend your create your own user_defined compset. Setting these up is not something that we recommend a beginner to do as it is very easy to setup a case which does not work scientifically.

 

[ybj]

Hi, It looks like the case you are running has a default flbc_file set

I found a related answer here: [Question] Different namelist for CO2 concentration in F compset and B compset ?

You are not able to override [the flbc_file] by setting co2vmr in your user_nl_cam file. If you want to do that, you will need to create your own use_case file. If you create your own use case, we also recommend your create your own user_defined compset. Setting these up is not something that we recommend a beginner to do as it is very easy to setup a case which does not work scientifically.

Thank you for your help.