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Raising atmospheric CO2 in CESM2.1.4 with CAM4 physics has no effect?

M

minminfu

Member
Hi! I am using release-cesm2.1.4, and trying to run an abrupt 4xCO2 coupled experiment using the CAM4 atmosphere, in a f09_g17 resolution. I am using the B1850C4L45BGCBPRP component set. However, when I change atmospheric CO2 from 284.7 ppm to 1138.8 ppm, the surface temperature does not increase, nor do I see any change in the net TOA radiative fluxes.

I am aware that CO2 needs to be set in the CAM namelist, so I have set co2vmr = 1138.8e-6 in user_nl_cam as well as set CCSM_CO2_PPMV to 1138.6 in env_run.xml

This same procedure worked in producing an abrupt4x CO2 simulation with the "out of the box" B1850 (CAM6) compset. Any idea what might be going on here? Thank you for your help!
 
M

minminfu

Member
I seem to have fixed the issue. "CAM_NAMELIST_OPTS" needs to be set to " co2_cycle_rad_passive=.true. " for the co2vmr to take effect.
 
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