Air pollution in national parks equal to that in largest U.S. cities, may be causing drop in visitors
Air pollution in U.S. national parks such as Yellowstone, Yosemite and Acadia is as bad as some of the nation's largest metropolitan areas, according to a new study. The study also suggests the foul air has caused visitors to cut their visits short or avoid going at all.
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Published By: USA Today - Wednesday, 18 July, 2018