Aerosol extinction coefficients are usually assumed to decrease exponentially with height, the assumption is approximately appropriate on conditions of long-term averaging but remain skeptical for a specific case. My question is how to judge by other atmospheric elements whether the aerosol extinction profile approximates an exponential distribution of not?
Thanks a lot for your reply!
I would suggest you to check for the mixing height. the extinction should be maximum with in boundary layer and should decrease significantly above that.
It is indeed a difficult question with no universal answer. Over urban areas the mixing layer (typically 0.5 to 2 km high) might force convection so that the aerosol concentration is relatively constant over height in that layer. But these processes are very dynamic, and typically change rapidly over short distances and time periods, even during a single day.
I guess you would have to run a chemical transport model, such as WRF-Chem, to obtain a precise time-dependent answer for your location, but it is obviously not an easy task...
@Muhammad
In Lidar data it is most often observed, at least in our region, that the AOD in residual layers above the planetary boundary layer is as high as in the BL.
Thank you very much for all your answers above, I would follow your suggestions to do some numerical experiments and see if there will be some new findings.
In my experience, you only get an exponential profile when you average several measured profiles. I was surprised when I averaged some 30 very different profiles and the results was a really nice exponential.
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