I am trying to use the DESID scaling in CMAQ5.4 and found that the semivolatile POA (e.g., ASVPO1) is mapping from both POC and PNCOM. It seems in the old version CMAQ5.2.1, it only maps from POC. Will it give a higher semivolatile POA if I use the same emission files for these two versions?
You may be able to use DESID to have some control over this. Please see the following DESID User Guide:
@Ben_Murphy may have other suggestions.
If you have POC and PNCOM on your emissions input files (all files that I work with have both of these), then ASVPO1 should be mapped from both POC and PNCOM.
In CMAQ v5.2.1 we implemented the PNCOM mapping in the source code so that it would be included if POC was mapped to ASVPO1 by the user. One of the important motivations for the DESID module in v5.3 and v5.4 was to make this step transparent, as you are seeing it now.