"Millions of tourists will head out into America’s national parks this summer in search of fresh mountain air. But according to a new report they should instead expect dangerous levels of pollution; roughly 96% of the nation’s parks are struggling with significant air quality issues.
The report, released yesterday by the National Parks Conservation Association (NPCA), found that some of the most popular parks, including Sequoia, Kings Canyon and Joshua Tree national parks and Mojave national preserve, were among the worst offenders. Last year, these parks recorded up to two months where ozone levels were considered dangerous –mostly in summer when visitation is at its highest.
In 88% of parks, the NPCA found that the elevated levels of air pollution was a direct threat to sensitive species. Air pollution is also exacerbating climate change, adding to a mounting list of threats to national parks that includes wildfire, drought and unnatural seasons."
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