Image credit: The Navajo Generating Station in Arizona was decommissioned in 2019. ©Oleksii Fedorenko/Shutterstock

Summer 2024

Code Red

By Katherine DeGroff

NPCA’s latest report on national park pollution paints a dire picture.

There’s something invigorating about simply standing in a national park and breathing deeply. The air just seems fresher. But unfortunately, parks aren’t as clean — or as insulated — as many people think. This March, NPCA released its second “Polluted Parks” report, which analyzed raw data collected by the National Park Service from nearly 400 of the 429 park units to determine how many of these sites are imperiled by dirty air, as well as by four climate-related threats: wildfire, drought, sea-level rise, and invasion by pests and pathogens. The results are alarming.

Air & Climate Report

Polluted Parks

National parks are home to some of America’s most iconic landscapes and best-preserved cultural and historic sites, and these places need clean air and a healthy climate to flourish. Yet…

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“We have a serious problem,” said Ulla Reeves, NPCA’s interim director of the Clean Air Program. While regulatory victories, such as the closing of coal-fired power plants, have netted modest air quality improvements since the last report in 2019, 98% of parks still suffer from hazy skies, and 96% experience worrying levels of ground-level ozone, which can inflame the lungs of staff and visitors. In addition, the data showed no improvement in the “harm to nature” category, which measures the impact of air pollution on parks’ plants and animals. The 2024 report also found that more than half of the parks are at risk from at least one climate threat capable of causing irreversible landscape changes.

Reeves hopes the troubling report motivates rather than disheartens, pointing out that it’s both possible and necessary to take action. “These things seem big, and it’s hard to imagine how you can have any role,” she said, but “we need people to be part of the solution.” Reeves cited a range of notable accomplishments, including NPCA’s decades-long efforts to hold polluters accountable and recent strides taken by the Biden administration to control methane, establish clean car standards and crack down on fine air pollutants. “We have folks who are really working hard right now to improve the situation,” she said.

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infographic Infographic by Selena Robleto.

About the author

  • Katherine DeGroff Associate and Online Editor

    Katherine is the associate editor of National Parks magazine. Before joining NPCA, Katherine monitored easements at land trusts in Virginia and New Mexico, encouraged bear-aware behavior at Grand Teton National Park, and served as a naturalist for a small environmental education organization in the heart of the Colorado Rockies.

This article appeared in the Summer 2024 issue

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