Is the 'Photolysis reactions' section of 'Update chemical mechanisms with KPP' out of date?

[bethkillen]

Your name

Beth Killen

Your affiliation

UNSW Sydney

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I am a new GEOS-Chem user and I have been trying to add new photolysis reactions into GEOS-Chem. I followed the instructions on the KPP readthedocs and my new reactions were not added to the simulation. According to the KPP page, the parameter JVN_ in the module 'Headers/CMN_FJX_MOD.F90' needs to be updated to match the total number of photolysis reactions. However, since GEOS-Chem now uses CLOUDJ as the default, I believe that the module that needs updating is 'Core/cldJ_cmnmod.F90'. Once I updated JVN in this module, the new reactions were added successfully. Is this the correct procedure? If so, could the KPP instructions be updated to reflect this change?

[yantosca]

Thanks for writing @bethkillen. Yes, that section is out of date. The JVN_ parameter is now found in Cloud-J/src/Core/cldj_cmn_mod.F90. We can update the documentation.

[yantosca]

Hi @bethkillen. I've pushed a fix for the documentations. You can see them at:

• https://geos-chem.readthedocs.io/en/latest/geos-chem-shared-docs/supplemental-guides/using-kpp-with-gc.html#photolysis-reactions
• https://gchp.readthedocs.io/en/latest/geos-chem-shared-docs/supplemental-guides/using-kpp-with-gc.html#photolysis-reactions

[bethkillen]

@yantosca That's great, thank you!