Lindsay_TJ
New Member
Hi everyone,
We are working with CESM 2.1.3 and trying to separate the specific climate responses (e.g., changes in surface temperature, precipitation, and circulation) to the anthropogenic aerosol direct radiative effect (ARI) and indirect radiative effect (ACI). Now，we have completed a BHIST base run and a BHIST-NoAnthro run. I now want to separate the anthropogenic aerosol direct and indirect radiative effects.
To isolate the direct and indirect effects, my initial thought was to run two additional sensitivity experiments based on the ones above, but with the aerosol indirect effects turned off.
I found that I could fix the ice and cloud droplet number concentrations in user_nl_cam by setting:
micro_mg_nicons = .true.
micro_mg_nccons = .true.
However, since I am running fully coupled B compsets, I am highly concerned that abruptly modifying these microphysics parameters to constants will severely break the TOA energy balance. This would likely lead to a massive climatological drift (e.g., severe SST drift) and ruin the baseline mean state.
Is there a safe and standard experimental design in CESM2 (CAM6) to isolate the climate responses of aerosol direct and indirect effects without breaking the coupled energy balance?
Instead of using a hard-coded constant (nccons = .true.), is it possible to prescribe 3D monthly climatologies of cloud droplet and ice number concentrations into the microphysics scheme? If so, which namelist variables or code modifications are required?
Any advice on the best practices for this experimental design would be deeply appreciated!
Thank you,
We are working with CESM 2.1.3 and trying to separate the specific climate responses (e.g., changes in surface temperature, precipitation, and circulation) to the anthropogenic aerosol direct radiative effect (ARI) and indirect radiative effect (ACI). Now，we have completed a BHIST base run and a BHIST-NoAnthro run. I now want to separate the anthropogenic aerosol direct and indirect radiative effects.
To isolate the direct and indirect effects, my initial thought was to run two additional sensitivity experiments based on the ones above, but with the aerosol indirect effects turned off.
I found that I could fix the ice and cloud droplet number concentrations in user_nl_cam by setting:
micro_mg_nicons = .true.
micro_mg_nccons = .true.
However, since I am running fully coupled B compsets, I am highly concerned that abruptly modifying these microphysics parameters to constants will severely break the TOA energy balance. This would likely lead to a massive climatological drift (e.g., severe SST drift) and ruin the baseline mean state.
Is there a safe and standard experimental design in CESM2 (CAM6) to isolate the climate responses of aerosol direct and indirect effects without breaking the coupled energy balance?
Instead of using a hard-coded constant (nccons = .true.), is it possible to prescribe 3D monthly climatologies of cloud droplet and ice number concentrations into the microphysics scheme? If so, which namelist variables or code modifications are required?
Any advice on the best practices for this experimental design would be deeply appreciated!
Thank you,