diagnostic radiative forcing

[ohmpawat]

Hi there,
I'm confused about how could I diagnostic radiative forcing. Take black carbon as an example. I know I need to remove the bc file in the variable "mode_refs". However, I don't know weather I should remove the bc file in the variable "ext_frc_specifier". Could someone tell me the function of the bc files in these variables? Any reply would be appreciated! Thanks.

 

[AshaJain]

I believe the file defined in mode_defs - 'A:bc_a4:N:bc_c4:black-c:/glade/p/cesmdata/cseg/inputdata/atm/cam/physprops/bcpho_rrtmg_c100508.nc' defines the physical properties of black carbon. However, the ext_frc_specifier - "emissions-cmip6_bc_a4_aircraft_vertical_1750-2015_1.9x2.5_c20170608.nc" actually determines the amount of black carbon emissions. So I think you'll want to remove the ext_frc_specifier file.

 

[ohmpawat]

I believe the file defined in mode_defs - 'A:bc_a4:N:bc_c4:black-c:/glade/p/cesmdata/cseg/inputdata/atm/cam/physprops/bcpho_rrtmg_c100508.nc' defines the physical properties of black carbon. However, the ext_frc_specifier - "emissions-cmip6_bc_a4_aircraft_vertical_1750-2015_1.9x2.5_c20170608.nc" actually determines the amount of black carbon emissions. So I think you'll want to remove the ext_frc_specifier file.

Thanks a lot! Your reply is really clear.

 

[AshaJain]

Thanks a lot! Your reply is really clear.

Hi again! I just learned that you may also need to remove content in num_a4 in ext_frc_specifer. At least when you try to increase an aerosol emission you need to specify a mass and number, so I imagine when you want to remove an aerosol emission you need to remove both the mass and number.

 

[ohmpawat]

Hi again! I just learned that you may also need to remove content in num_a4 in ext_frc_specifer. At least when you try to increase an aerosol emission you need to specify a mass and number, so I imagine when you want to remove an aerosol emission you need to remove both the mass and number.

I tried it. And I also remove bc in "the mode_defs". There are differences between these two tests. Do you know the reason?

 

[AshaJain]

I tried it. And I also remove bc in "the mode_defs". There are differences between these two tests. Do you know the reason?

Can you clarify which two tests you ran?

 

[ohmpawat]

Can you clarify which two tests you ran?

1. remove the bc file in the "ext_frc_specifier" and "srf_emis_specifier"
2. remove the bc file in the "mode_defs"
I compared the FLNT in the first test history file to the FLNT_d1 in the second history file. They are different.

 

[AshaJain]

1. remove the bc file in the "ext_frc_specifier" and "srf_emis_specifier"
2. remove the bc file in the "mode_defs"
I compared the FLNT in the first test history file to the FLNT_d1 in the second history file. They are different.

I am not sure. This is above my current level of understanding. You may need to reach out to one of the cesm liaisons.

 

[ohmpawat]

OK. Thanks for your patient reply!

I am not sure. This is above my current level of understanding. You may need to reach out to one of the cesm liaisons.