I've stood a few hundred feet downrange (downwind?) from small bizjet engines and its noticeable but hardly overwhelming, which makes the whole discussion very

I've stood a few hundred feet downrange (downwind?) from small bizjet engines and its noticeable but hardly overwhelming, which makes the whole discussion very strange in that the inversion must not be broken mechanically or fluid dynamically or it must be incredibly close to the ground. Clearly concentrated heat from the exhaust doesn't crack the inversion of the chimneys would "naturally" take care of the problem. My immediate assumption is this has gone thru the journalist filter too many times... decades ago we were able to make catalytic converters that ate hydrocarbons so effectively that car exhausts were cleaner on average than California air. Heck its even been run thru a particulate filter before the carburetor. Now I'm not sure this is the case as cat conv are only a little better and California air is so much cleaner its nearly transparent, so I'm told. Anyway, jet engines usually run pretty lean so I figured somewhat more CO2 could be traded for zilch hydrocarbon leading to zero to no smog if you blew all the air in a city thru an operating jet engine.