Report: Bad air threatens national parks
WASHINGTON (CNN) -- Some of America's national parks are choking on air as polluted as that of Los Angeles, California, or Atlanta, Georgia, according to a report issued by a parks support and lobbying organization.
The National Parks Conservation Association compared data from the 10 national parks with the most extensive monitoring programs, then ranked the most polluted parks based on three impacts -- haze, acid precipitation, and ground-level ozone.
The Washington-based group's report is titled "America's Five Most Endangered National Parks." Those parks are:
Great Smoky Mountains National Park in Tennessee and North Carolina, where ozone pollution rivals that of Los Angeles, and the mountaintop clouds that blanket sensitive spruce-fir forests can be as acidic as vinegar, leading to nitrogen-saturated soils
Shenandoah National Park in Virginia, where the views can be limited to less than a mile in the summer due to high levels of fine-particle pollution, and where acid in streams put trout and other fish species at risk
Mammoth Cave National Park in Kentucky, where visitors who come for spectacular ridge-top views often find vistas among the haziest in the nation, and where rainfall is 10 times more acidic than natural conditions
Sequoia and Kings Canyon National Parks in California, two adjacent parks where ozone levels surpassed human-health standards on 61 summer days in 2001, and where harmful haze affects sequoia seedlings and scenery
Acadia National Park in Maine, where acid rain, fog and snow have created critically acidified lakes and impaired scenic views
The association has found that, aside from the national parks, many other public lands, such as wildlife refuges and other wilderness areas, also suffer from harmful air-quality levels.