A Massive 96% of National Parks Suffer from Air Pollution | 33 Parks Are as Polluted as the 20 Largest Cities The effects of air pollution on the national parks are even more widespread and distressing than we thought. 33 of America’s most-visited national parks are as polluted as the 20 largest cities, a recent report from the National Parks Conservation Association shows. Related: New Data: Air Pollution Impacts 92% of World’s Population A massive 96% of the 417 national parks are troubled by […] SnowBrains | June 10, 2019 0 Comments