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Bug in the organic aerosol formation

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New member
Hi everyone,

I am running WRF-Chem version 4.2.1 and am using chem_opt = 11 (RADM2-MADE/SORGAM-AQ). I add one new aerosol species in this chemistry scheme and only revise the anthropogenic emission for this new species. I have not revised any code related with chemical reactions or secondary organic aerosol (SOA) formation.

However, it seems that there is a bug for secondary organic aerosol (SOA) formation. In the result, the concentration of SOA from aromatic organics (orgaro1i, orgaro1j, orgaro2i, and orgaro2j) has the same pattern as the new species, as figures below. It seems that SOA use the anthropogenic emission of the new species, or SOA take the new species into the secondary organic aerosol formation.

New species.png


When I revised the codes, I did the following 7 things, as below.

(a) Under "# aerosol variables for MADE/SORGAM" in the "registry.chem", I created three variables for the new species in Aitken, Accumulation, and Coarse mode.

(b) Under "# aerosol stuff" in the "registry.chem", I created one variable as the total dry mass of the new species in 3 mode.

(c) Under "# Anthropogenic emissions" in the "registry.chem", I created three varibales as anthropogenic emissions of this new species in 3 mode.

(d) Under "package radm2sorg_aq chem_opt==11" in the "registry.chem", I added the three aerosol variables at the end of chem array.

(e) Under "package eradmsorg emiss_opt==3" in the "registry.chem", I added the three emission variables at the end of emis_ant array.

(f) In the "module_data_sorgam.F", I added some constants (density, molecular weight, indices for array CBLK) for this new species with reference to PM2.5 aerosols.

(g) In the "module_aerosols_sorgam", I added the anthropogenic emission for the new species, and take the new species into the calculation of the 3rd moment in all 3 modes.

Thank you.
Attached is the namelist.input that I used. I have done some tests for different simulation areas and different simulation periods. But the results show that this bug is always there.


  • namelist.input
    6.8 KB · Views: 43
Hi, Jordan,

Attached are the changed files. The Word file in this attachment concludes all revisions that I made to WRF-Chem codes.

Thank you.


  • Revised WRF-Chem codes.rar
    1.6 MB · Views: 50