Process Analysis doesn't produce IRR output file

Hi, I’m using PA to get H2O2 and HNO3 production rate, the model can run normally but there is not IRR output file produced. I tried IPR and got the IPR output. Does anybody knows why?
pa_cb6r3_ae7_aq_ctl_NV.txt (261 Bytes)
PA_REPORT_20201210.txt (6.3 KB)


I’m not certain, but I suspect you need to specify IRR_TYPE=PARTIAL; in your PA control file.

I think @cgnolte is right. See the quote below from the users guide

IPR files are only created if IPR is turned on in the PACM_INFILE (IPR_OUTPUT specified), and IRR files are only created if IRR is specified (IRRTYPE = PARTIAL or FULL).

More details are available in Chapter 9 CMAQ/ at master · USEPA/CMAQ · GitHub


Thank you and this is the reason!
The Users Guide says: The number of output files created (whether 1,2 or 3) depends on the number of variables specified for IRR, but I still don’t know the meaning. When will the model create multiple IPR or IRR output files? It seems working when I specify only 1 file in runscript.


There is a limit of MAXVARS3 variables per file in IOAPI. In the past, MAXVARS3 was set to 120, and if you had more IPR or IRR variables than that then they would be split across multiple files. A few years ago, however, MAXVARS3 was increased(*), and it is now unlikely that you will need more than one output IPR or IRR file.

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