American Thinker
Dexter Wright
Sept. 23, 2018
Eighty-seven days of continuous poor air quality in Los Angeles County and the surrounding areas are now over. This is the longest stretch of uninterrupted heavy smog for the L.A. area in twenty years. As with all things environmental, the media will blame Donald J. Trump. However, the reality is quite different.
Smog is formed from a combination of tailpipe emissions of nitric oxides (NOx), sunlight, and volatile organic compounds (VOCs). The VOCs can be the result of a variety of natural and man-made sources such as pine trees, brewing beer, and gasoline vapors. NOx is generated from burning gasoline or diesel fuel under compression in an internal combustion engine. The VOCs react with sunlight and NOx to create oozone (O3). Ground-level ozone is the brown haze that we call smog.
The catalytic converters on automobiles today work to reduce NOx emissions but not eliminate them entirely. The catalytic converter works only when the heat of the exhaust gases has reached a threshold temperature, so for the first ten minutes of run time on a car, the emissions of NOx are unabated. Additionally, over time, the catalytic converters get contaminated and degrade in effectiveness at reducing NOx emissions.
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https://www.americanthinker.com/blog/2018/09/the_cure_for_air_pollution.html