In 1859 John Muir built a Sugar Pine cabin some yards from the spot above and lived in the Valley for 2 years. Sugar Pines can live 500 years, so the decades John Muir spent saving this valley are just a fraction of their long lives. Muir saved Yosemite, lost neighboring Hetch Hetchy to a dam, and influenced Teddy Roosevelt who ended up protecting 150 million acres of forests nationally. Now the park is a World Heritage Site too. But in the near future, the crown jewel of John Muir’s legacy may still be lost forever.

Some species of trees still living here evolved in the Jurassic, long before the Chicxulub asteroid wiped out most dinosaurs and millions of years before humans arrived. Millenia ago, natives started fires for hunting and agriculture, and over a century ago, the timber industry clear cut forests throughout the Sierra Nevadas. But humans now present a threat bigger than any logging or dam. Now the threat is carbon pollution, which dwarfs all others, even logging. Fires burn hotter, more frequently and many times larger, because we have changed our planet’s climate dramatically—and it’s still getting worse. Species here, despite evolving 1000 times earlier than humans, are now threatened with extinction by our vehicle exhaust.

10 years ago, the 250,000+ acre Rim Fire burned over 10% of Yosemite, killing many Sugar Pines and Sequoias that had survived fires for centuries or millennia. At the time, it was the second largest fire in California history. Now it doesn’t even make the top ten. I visited the park with my family before that fire, and the park was undamaged. Now, the park is still beautiful, but it is still scarred badly, with many areas still closed.

Yosemite Falls should not be so glorious in the photo above taken in July. The snow should still be on the mountain tops, melting slowly over many months. Instead, every decade is warmer than the last and the rate of temperature rise in increasing. The Lyell Glacier that Muir saw in Yosemite has lost over 95% of its mass, no longer moves and will be gone in a few years. Man has messed up the climate, and many of the species, including the largest trees, can no longer live here safely. And it’s not the fault of Smoky Bear telling people to put out their campfires, it’s the fault of people who continue to drive gas powered vehicles. And yet the park is full of them, blithely surveying the damage they contributed to and continue to cause. If I were in charge of the park service, I would convert the shuttle buses to electric and ban all fossil fuel vehicles.