CMAQ simulates low ozone concentrations at night

Hello everyone.
I have been using CMAQ to simulate ozone with very low nighttime concentrations, near 0 ppb, resulting in my monthly averages being much underestimated, with simulated averages of just under 15ppb, but monitored values of 40ppb. There is no error in my emission inventory production.
Thank you for your answer!

Have you been able to resolve your issue?
Please provide information according to these instructions: PLEASE READ before posting

At a minimum, please include:

  1. region or domain
  2. model resolution
  3. model version for CMAQ
  4. example run script and log files.

I’m sorry it took so long to see your message.
I have found the cause of the problem, mainly because I did not enter emissions from natural sources in my emissions inventory. That’s why the ozone simulation values are low.

Are natural sources you mean here are biogenic emissions, wild fires emissions, or lightning NOx emissions. If biogenic emissions are the case, I do not think the natural sources impact your night ozone levels significantly.

You may check your boundary condition files (BCON) and make sure ozone and ozone precursors are included.