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photochemical smog

photochemical smog A hazy condition of the atmosphere caused by the reaction of hydrocarbons with molecules of nitrogen oxide in sunlight, which produces complex organic molecules of peroxyacetyl nitrates (PAN). In humid conditions these molecules produce smog. Such phenomena are common in large urban areas (e.g. the Los Angeles basin and Athens) where there are stable atmospheric conditions and a high level of hydrocarbon input from incomplete combustion in car engines. Natural photochemical reactions occur in the high atmosphere with the absorption of radiation by oxygen to produce ozone. See also ozone layer.

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"photochemical smog." A Dictionary of Ecology. . Encyclopedia.com. 20 Aug. 2017 <http://www.encyclopedia.com>.

"photochemical smog." A Dictionary of Ecology. . Encyclopedia.com. (August 20, 2017). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/photochemical-smog-0

"photochemical smog." A Dictionary of Ecology. . Retrieved August 20, 2017 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/photochemical-smog-0

photochemical smog

photochemical smog Hazy condition of the atmosphere due to the reaction of hydrocarbons with molecules of nitrogen oxide in sunlight which produces complex organic molecules of peroxyacetyl nitrates (PAN). In humid conditions these molecules produce smog. Such phenomena are common in large urban areas (e.g. the Los Angeles Basin and Athens) where there are stable atmospheric conditions and a high level of hydrocarbon input from incomplete combustion in car engines. Natural photochemical reactions occur in the high atmosphere with the absorption of radiation by oxygen to produce ozone. See also OZONE LAYER.

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"photochemical smog." A Dictionary of Earth Sciences. . Encyclopedia.com. 20 Aug. 2017 <http://www.encyclopedia.com>.

"photochemical smog." A Dictionary of Earth Sciences. . Encyclopedia.com. (August 20, 2017). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/photochemical-smog

"photochemical smog." A Dictionary of Earth Sciences. . Retrieved August 20, 2017 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/photochemical-smog

photochemical smog

photochemical smog A noxious smog produced by the reaction of nitrogen oxides with hydrocarbons in the presence of ultraviolet light from the sun. The reaction is very complex and one of the products is ozone. See also air pollution.

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"photochemical smog." A Dictionary of Biology. . Encyclopedia.com. 20 Aug. 2017 <http://www.encyclopedia.com>.

"photochemical smog." A Dictionary of Biology. . Encyclopedia.com. (August 20, 2017). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/photochemical-smog-1

"photochemical smog." A Dictionary of Biology. . Retrieved August 20, 2017 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/photochemical-smog-1