Including N2O in CMAQ Simulations

Hi everyone,

I’m looking to include N2O (nitrous oxide) in my CMAQ modelling workflow and would appreciate any guidance or examples from the community.

My goal is to simulate N2O transport (and possibly simple chemistry) over a regional domain using CMAQ v5.4 or 5.5. I understand that N2O isn’t part of the default chemical mechanism, but I’d like to include it at least as a passive tracer, ideally linked to custom emissions (e.g. from agricultural soils or traffic) and appropriate boundary and initial conditions.

Specifically:

  • Has anyone successfully added N2O as a passive or reactive species in CMAQ?
  • What changes were needed in the species definitions? I assume I’ll need to prepare emissions input and set up initial and boundary conditions for N2O.
  • Any examples, tips, or advice would be very welcome!

Thanks in advance,