The Air In California's National Parks Can Be As Bad As L.A.'s

You might think of our national parks as pristine wilderness, but it turns out the air in some of California's parks are as bad as L.A.'s.A recent report found that four of the worst national parks for air quality are in California, all getting F-grades in air quality and also receiving poor marks in visibility. Sequoia and Kings Canyon (which are adjacent to each other) received the ignoble honor of topping the list, while Yosemite and Joshua Tree also made appearances in the top 10. The National Parks Conservation Assocation took a look at the air quality in the 48 parks with the strictest federal regulations, and found that not only was visibility down by an average of 50 miles across all parks, but that several also had very unhealthy levels of ozone in the air.

In Sequoia and Kings Canyon, parks known for their giant trees and Sierra Nevada locale, visibility has been reduced by about 90 miles. The study also looked at the effect climate change had on the parks, with the four California parks receiving poor marks in that regard. Ironically, poor air at least makes for spectacular sunsets.

Although the California parks in the top 10 are away from big cities, they are plagued by emissions from visiting cars, pollution blown in from afar, and the ammonia from the Central Valley's dairy farms. Nationally, coal-burning plants are the biggest culprit. The NPCA says ineffectual laws and regulations will keep national parks and natural areas across the country from reaching their goal of having clean air by 2064 as required by the EPA (.pdf). Under current trends and conditions, Joshua Tree won't reach that goal until 2106 (.pdf).

"If the regional haze rule is not improved, in 50 years only 10% of our national parks that are required to have clean air will actually have it," said the NPCA's Ulla Reeves, who is in charge of their clean air campaign.

Ozone is the most hazardous pollutant to park visitors, as it can cause respiratory problems and trigger asthma attacks. Although the national parks generally have less ozone in their air than Southern California, the L.A. Times points out it can nearly be as bad. Last year Southern California had 92 days of "unhealthful air" days, or days with an ozone concentration of at least 75 parts per billion. In 2014, Joshua Tree and Sequoia/Kings Canyon each logged at least 40 bad air days with at ozone levels reaching the low-90s.