Abnormal ozone vertical contribution results with PROCESS ANALYSIS, CMAQ5.3.1

Hello everyone,
I am using cmaq5.3.1 and cb6r3_ae7_aq mechanism. Recently I am learning process analysis of ozone concentration. But there are some problems with the results. From the IPR output file, DDEP contributes a lot to ozone as shown below. But the ozone concentration is ~30 ppb. the contribution of other processes is very small above the vertical layer. I am not sure whether this is correct. Any comments would be appreciated!
@Ben_Murphy @hogrefe.Christian
Thanks very much for your help!
Best wishes,

Thanks for posting these results.

Yes, the very large and mostly counteracting DDEP and VDIF contributions for layer 1 are expected. Dry deposition is only active at the surface so it only has a non-zero contribution in layer 1, and a large portion of the removal of O3 through that process is counteracted by downward mixing of ozone into layer 1 through VDIF such that the net effect / sum of all IPR terms (i.e. the net rate of change for O3) is on the order of a few ppb/hr like it is for the higher layers in your plot.

Your profile for contributions in the layers up to 3 km seems consistent with some IPR analyses we included in a paper a few years ago (see Section 3.1.2 and Figures 4-5), though of course the actual magnitudes will depend on the specific domains and time periods being simulated and analyzed.