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Aerosol optical depth too low despite aerosol concentrations being sensible.


New member
Hi all,
I am using WRF-Chem to examine cloud/aerosol interactions in Australia. The model simulates aerosol concentrations reasonably well, but the aerosol optical depth (calculated from the EXTCOFF55 variable) is approximately an order of magnitude too low.
Does anyone have any advice on how to diagnose this problem?
I suspect it could be the column ozone profile. I'm struggling to find where this is defined, should I be looking in RRTMG, or in the photolysis code ( I am using the FAST-J photolysis scheme, phot_opt=2 , and CBMZ-MOSAIC chemistry/aerosol scheme ).

The ozone column will not have an impact on EXTCOFF55 -- are you sure you are calculating AOD correctly (i.e., summing EXTCOEFF*DZ through all of the layers?)