doubts and question ghg (co2vmr and other) setting in CAM4 run

[cam_iitd10@gmail_com]

Dear Sir,

I am using the CAM4 for a time slice experiment (2070-2100) with some sst/sea-ice boundary conditions and "ramped" ghg_scenario using the ghg file ghg_ipcc_A1B_1870-2100_c040521.nc - so the co2vmr is around 605ppm (and increasing) which is verified from the history files.

In the log file I see these lines:
**********************************

model physics parameters:
flag for random perturbation test is not set
CO2 volume mixing ratio (umol/mol) = 355.000000000000
urban air conditioning/heating and wasteheat = ON_WASTEHEAT
urban traffic flux = F
maxpatch_pft = 17
allocate_all_vegpfts = T
nsegspc = 20
************************************

My questions are:
1.Does something have to be done to the physics parameters for the model to accept co2vmr values of this range?
2.If so, where does one set it?
3. If not, what does the log file message imply?

thank you so much in advance.....

Ram
IIT Delhi-110016
INDIA

 

[eaton]

How are you setting up this experiment? cesm1_0_2 doesn't have any support for running future scenarios. If you are running CAM in an "AMIP" mode with time varying SST, and a ramped GHG dataset, that doesn't change how CLM experiences the atm CO2 values. The log message you report is from the CLM. Unless the CLM is set up to have dynamic vegetation then I would guess that it doesn't matter what value of CO2 the CLM reports. I don't know the details of how CLM deals with CO2, so more specific questions about that should be posted to the CLM section of the bulletin board.