Does old emission input data work with new version of CMAQ-5.3.1?

Hi everyone,

I am a new learner of CMAQ and i use the latest CMAQ-5.3.1 version. I am now rerunning one of my senior’s simulation and got the emission input data directly from her. She is using CMAQ-5.0.2 and SMOKE-4.0. So the emission data i got is generated using SMOKE-4.0 and the chemical mechanism is cb05. But in CMAQ-5.3.1 the cb05 chemical mechanism is updated to cb6. Could i use the emission inventory directly? Do i need to regenerate the emission input data myself because of the update of the chemical mechanism?

Lin

Hi Lin,
There are multiple things to consider, but you should be able to create a first order mapping using the DESID emission control file.

For aerosol purposes:

  1. naphthalene should ideally be split from XYL. This is minor. See https://www.airqualitymodeling.org/index.php/CMAQv5.1_VOC_Emission_Updates
  2. SOAALK should ideally be considered. This is minor. See https://www.airqualitymodeling.org/index.php/CMAQv5.1_VOC_Emission_Updates
  3. a-pinene needs to be split from other monoterpenes (TERP) if using aero7 (highly recommended over aero6). See require emission updates here: https://github.com/USEPA/CMAQ/blob/master/DOCS/Release_Notes/aero7_overview.md. This update is important for PM2.5 performance and failing to split out APIN will result in overestimates in PM2.5 (particularly in vegetated locations).

This does not cover updates that may be needed for gas-phase chemistry (Ramboll/Environ may have documentation as well as the CMAS wiki covering updates since v5.0.2).

Havala

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Thank you sooo much!