America's four most polluted national parks are in California, study finds

The York fire last year torched an untold number of Joshua trees in the Mojave National Preserve — on top of those incinerated in the 2020 Dome fire, turning a portion of the preserve into a “graveyard of Joshua tree skeletons,” according to the National Park Service. More of the iconic desert trees were mowed down by another 2020 fire in Arthur B. Ripley Desert Woodland State Park.

Between 2020 and 2021, three fierce wildfires are estimated to have killed 19% of all giant sequoias in their limited range in the Sierra Nevada mountains, which includes parts of Sequoia and Kings Canyon National Parks and Sequoia National Forest. Sequoias need fire to reproduce, but the supercharged blazes of recent years have become lethal to the trees already weakened by drought and bark beetles.

Many ancient redwoods were seared in a 2020 fire that devastated 97% of Big Basin Redwoods State Park, the oldest state park, according to the state parks foundation report.

Compared to the 2019 Polluted Parks report, there was no improvement in the harm to nature category. The evaluation is based on levels of sulfur and nitrogen that make their way into soil and water, as well as ozone pollution’s impact on trees and plants.

For the harm to nature category, 69% met the criteria for significant concern, with nitrogen deposition playing an outsize role. Nitrogen and sulfur, which are washed out of the sky by precipitation, can contaminate soil and water. High levels of nitrogen can trigger algal blooms and kill fish, the report notes.

Reeves said the report provides another lens to see how climate change and air pollution are wreaking havoc on the world, “because not only are our communities and people experiencing these problems, but these places that we love, and that we want to protect.”

Hopefully, she said, the dire findings in the report will motivate people to do more to safeguard national parks for future generations.

Recommendations in the report include finalizing new vehicle emission standards, as well as establishing air quality standards for ozone and fine particulate matter specifically to protect scenic views and nature.

The report also suggests amending regulations intended to improve visibility in national parks across the country, known as the Regional Haze Rule, to address flaws — and holding polluters accountable for their negative impacts on parks.

Rachel Norton, executive director of California State Parks Foundation, made the case that state parks can provide a solution to climate change woes.

California State Parks, the agency overseeing the state park system, manages an astounding 1.6 million acres of land. Norton described the parks as a “lever that the state really has full control over.”

While California can’t pass laws that govern national parks, it can make budget decisions for its own parks, she said. The state parks foundation in its recent report advocates spending tens of millions of dollars to address wildfire and sea-level rise at the parks, as well as hiring permanent staff to work on climate change-related efforts.

“And if [the state] chooses to not invest, and not see these places as essential and critical to the success of our climate goals, then we might fail,” she said. “And that’s kind of unthinkable.”