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It is the immediate effect of on urban atmospheres that is most noticeable and causes the strongest public reaction. The city of Los Angeles has been noted for both the extent of its and the actions undertaken for control. Los Angeles lies in a coastal plain, ....

Middle of Essay
.... as a result of the increased number of motor vehicles. Exhaust fumes from the engines of automobiles contain a number of polluting substances, including carbon monoxide and a variety of complex hydrocarbons, nitrogen oxides, and other compounds. When acted upon by sunlight, these substances undergo a change in composition producing the brown, photochemical smog for which Los Angeles is well known. Efforts to reduce pollution from automobile engines and to develop pollution-free engines may eventually eliminate the more serious problems. In the meantime, however, has driven many forms of agriculture from the Los Angeles basin, has had a serious e ....