Photolysis rate of NO2 (jNO2) about geos-chem

[yantosca]

Thanks for writing @ks3506. GEOS-Chem 14.2.0 and prior versions use the FAST-JX photolysis scheme to compute the photolysis rates. See this link for references.

GEOS-Chem 14.3.0 and later will use Cloud-J, which is an updated version of FAST-JX.

Tagging @lizziel

[lizziel]

Hi @ks3506, let us know if you have a more specific question than generally how the model calculates the rate. We can point you to code or direct you to the Chemistry Working Group, depending on what level of detail you need. Note that the wiki page @yantosca pointed you to has not been updated for a while. However, the general information is correct. The latest photolysis data files read into Fast-JX (14.2 and prior are here). The same cross-section data, simply modified for format, are used in Cloud-J and are stored here. You can search the files for NO2 to see notes specific to that species. Also note that Cloud-J differs from Fast-JX primarily in that it handles clouds differently than Fast-JX.

[yantosca]

Closing out this issue