Larry Dighera wrote:
On Wed, 4 May 2016 17:03:56 -0000, wrote:

In the LA area, air concentrations of volatile organic compounds declined
by a factor of 50 between 1962 and 2012. Nitrous oxides and ozone declined
by 70% to 80% over the same period of time.

I recall in the mid '50s in the Los Angeles area when homeowners burned their
trash in backyard incinerators. It wasn't pretty.

Then as freeway construction became completed, the air quality was so bad, that
it hurt to inhale, eyes burned, and it was generally unbearable.

Subsequently, California emissions control laws have made a very substantial
positive impact on improving air quality, but that's not to say the air quality
is good.

There were a LOT of changes in the law on everything; trash burning, industry,
farming, painting, vehicles, etc.

LA smog did not just come from cars and entire industries have been legislated
out of existance.

Here's some supporting evidence:

http://www.latimes.com/science/la-me-0430-air-pollution-20140430-story.html

L.A., Central Valley have worst air quality, American Lung Assn. says

Which has more to do temperature inversions due to geography than anything
else.

snip

The ports of L.A. and Long Beach are the largest single source of air pollution
in the region.

There are no solar powered ships nor 18 wheelers anywhere in the future.


--
Jim Pennino