How Sequoia became the most polluted national park in America

A news photographer is dwarfed by a giant sequoia
(Brian van der Brug / Los Angeles Times)

Good morning. It’s Monday, March 25. I’m Christian Orozco, an editor on the newsletters team. Here’s what you need to know to start your day.

California’s unflattering achievement

You are tired of the city and the traffic. You’re looking to break away from the expanding industrial facilities encroaching on open spaces. So you drive up to Sequoia and Kings Canyon National Parks.

Congratulations, you’ve made it to the most polluted parks in America.


Sequoia and Kings Canyon topped two lists in the National Parks Conservation Assn.’s report on polluted parks, “National Parks With Unhealthy Air” and “Worst National Parks for Hazy Skies,” my colleague Lila Seidman reported. Joshua Tree, Mojave, Yosemite and Death Valley were also ranked in the top 10 on the unhealthy-air list.

The report called Sequoia, Kings Canyon, Joshua Tree and Mojave “the most ozone-polluted national parks in the United States,” with the ozone layers being “significant concern for human health.”

Wildfire smoke has left California parks worse off than parks in other states

Although California parks join the rest of the nation in the fight against threats related to climate change, the Golden State is also disproportionately affected by wildfires, Seidman reported.

Sequoia and Kings Canyon National Parks took the No. 1 position partly because of the 2020 Castle and the 2021 KNP Complex wildfires. (They also took the No. 1 position the last time the report was published, in 2019.)

According to the report, the fires destroyed “tens of thousands of acres and numerous sequoia groves within the parks.” The destruction of sequoias “not only threatens the regeneration of the iconic trees but also disrupts ecosystems and harms wildlife within these parks.” It added that “19% of the world’s mature giant sequoias may have been lost due to wildfires.” California’s Joshua trees have suffered a similar fate in the face of the state’s wildfires.


Pollution from population and industrial centers also affects our parks

Seidman wrote that “car-dependent population centers such as Los Angeles; agricultural and industrial operations in the San Joaquin Valley; trucking and warehouse facilities in the Inland Empire; and the ever-buzzing ports complex in Los Angeles and Long Beach” are what have made California parks dirtier.

Half of the 10 parks with the unhealthiest air are in California. Here they are:

  1. Sequoia & Kings Canyon (Calif.)
  2. Joshua Tree (Calif.)
  3. Mojave (Calif.)
  4. Yosemite (Calif.)
  5. Carlsbad Caverns (N.M.)
  6. Death Valley (Calif.)
  7. Indiana Dunes (Ind.)
  8. Guadalupe Mountains (Texas)
  9. Rocky Mountain (Colo.)
  10. White Sands (N.M.)

It’s not all bad news

Despite the grim circumstances, the report noted some hopeful improvements from 2019:

  • Parks with significant concern levels in at least one of the air quality categories fell from 96% to 70%.
  • Significant concern levels for unhealthy air fell by 52%.
  • Hazy skies decreased by 94%. (Seidman notes the report attributes this “to the implementation of several clean air regulations.”)

Today’s top stories

Los Angeles Dodgers' designated hitter Shohei Ohtani, right, chats with his interpreter Ippei Mizuhara in the dugout.
(Lee Jin-man / Associated Press)

The Shohei Ohtani interpreter gambling scandal

The presidential election

Dodgers and Angels square off to open the MLB season

The box office isn’t quite back

Call them super progressives

‘Quiet on the Set’ has forced many to revise childhood memories

The Klamath River is making a comeback

More big stories


Get unlimited access to the Los Angeles Times. Subscribe here.

Commentary and opinions

Today’s great reads

The Miracle Hot Springs soaking tubs before they were closed due to two recent deaths.
(Forest Service / U.S. Department of Agriculture)

Two dead bodies, drugs and ‘weird characters.’ Are these illicit hot tubs a safety threat? Sequoia National Forest has waged a long-running battle against illegal hot tubs, but lovers of Miracle Hot Springs say authorities need to chill out.

Other great reads

How can we make this newsletter more useful? Send comments to


For your downtime

Chef Daniele Uditi holds a piece of focaccia nel ruoto
Chef Daniele Uditi holds a piece of focaccia nel ruoto at the 40th annual International Pizza Expo in Las Vegas. The Pizzana chef hopes to open a focacceria in Los Angeles.
(Jenn Harris / Los Angeles Times)

Going out

Staying in

And finally ... a powerful photo

Show us your favorite place in California! We’re running low on submissions. Send us photos that scream California and we may feature them in an edition of Essential California.

A boy sits quietly
(Marcus Yam/Marcus Yam / Los Angeles Times)

Today’s powerful photo is from staff photographer Marcus Yam. On a bright and nearly cloudless day in the West Bank village of Burin, hundreds gathered to bury a 10-year-old boy named Amro, who had been shot and killed by Israeli soldiers. Yam captured one boy’s grief.

That’s it for today from the Essential California team


Christian Orozco, assistant editor
Karim Doumar, head of newsletters

Check our top stories, topics and the latest articles on