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Just as I quoted the setting method in the forum, why setting progn=0 is to turn off the aerosol indirect effect?

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cxyiyh

Member
Hi,friends,
Just as I quoted the setting method in the forum, why setting progn=0 is to turn off the aerosol indirect effect? Does this approach accurately indicate that the aerosol cloud interaction is turned off?
I just know setting progn=0 means no prognostic aerosols.
gc13141112 said:
setting namelist.input for no aerosol feed back
progn = 0
ra_lw_physics = 4
ra_sw_physics = 4
chem_opt = 2
aer_ra_feedback = 0

setting namelist.input for aerosol direct effects
progn = 0
ra_lw_physics = 4
ra_sw_physics = 4
chem_opt = 2
aer_ra_feedback = 1

setting namelist.input for aerosol direct and indirect effects
progn = 1
ra_lw_physics = 4
ra_sw_physics = 4
chem_opt = 2
wetscav_onoff = 1,
cldchem_onoff = 1,
aer_ra_feedback = 1

The three figures in attachments
Another questions is setting chem_opt = 2 seems to have no aqueous phase chemistry.How do I consider the role of aqueous phase chemistry in the cloud?

Thanks to everyone who discussed and answered my questions!

Best Regards!

yours,
cxyiyh
 
Hi,

The namelist values you have indicated are correct, however, as you note, you will need to choose a mechanism that includes aqueous phase chemistry. Please refer to either the user guide or Registry/registry.chem and search form a chem_opt that has a *_aq extension in the name.

Jordan
 
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