Low simulated PM2.5 concentrations of CMAQ results

Hello everyone,

I get a question about CMAQ results. I have tried to simulate PM2.5 for several times using CMAQ, but all got low concentrations. However, the simulated PM2.5 from WRF-Chem are comparable with observations during the same period. I wonder if there are some errors of my emission files or errors from my run_cctm.csh setting. Actually, I have double checked my emission files, and the value is comparable with the value in some references.
run_cctm_hj.csh.txt (35.6 KB)

Take a look at one of the processor-specific log files, e.g., CTM_LOG_000. Look for the section where emissions are being read, and check to see if the model reports that key species are not found. What mechanism did you use in compiling the model, and does that match your emissions species?
If this does not help, provide more details, including model version and log files. Please also see the “PLEASE READ before posting” message.

I used cb6r3_ae7_aq in compiling the CMAQ-5.3.2, and also CB6_AE7 emissions species are used in the model. According the log file attached below, I think emissions are all being read in CMAQ.
CTM_LOG_249.v532_gcc_2022XZQ_20220112.txt (1.6 MB)

We do not see anything obvious in your log file. Here are a few ideas that may help in debugging.

  • You might try turning on emissions diagnostic files and verify that the totals are as you expect.

    setenv EMISDIAG T
    setenv EMISDIAG_SUM T

  • How low are the PM2.5 concentrations, and what values are you obtaining using WRF-Chem? Are all PM components low, or is the problem mostly inorganics, organics, or unspeciated PM?

  • What physics options are you using with WRF-Chem? It is possible you are using a configuration that is not handled well by MCIP and CMAQ.

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