Climate sensitivity

The atmosphere around LA is polluted by smog, yes.
Particularly since "the air" you refer to as being polluted is actually the troposphere, the lowest layer of our atmosphere.
http://www.pnas.org/content/100/21/11975.full.pdf+html

If someone dumped a bunch of pollutants into the ocean, and a significant portion of them sank to the lowest point, would you say that the ocean was not polluted because it was only the lowermost layer that was affected?

 

So the smog is not atmosphere? It is suspended in the air above town right? So why doesn't the smog rise? And if smog doesn't rise, I'm not sure how it gets to the upper atmosphere to add to the gas levels.

 

Are you aware that "smog" is made up of a combination of different substances?
Some are lighter than others and will rise to the upper atmosphere, others aren't and won't.

Seriously, I don't know why I'm answering such basic questions that seem to have no point.