### How the world keeps ending

“This Earth is a story teller,” Childs began. “And it is not a stable place to live. It is always ending. We think of endings as sudden, but it is always a process.”

For his book _Apocalyptic Planet_ he sought out some of the world’s most terminal-feeling places, where everything is reduced to fundamental elements in total upheaval or total stasis, and a visitor is overwhelmed by the scale and power of a planet going about its planetary business.

In Yosemite Valley, where Childs was the day before he spoke in San Francisco, everyone is awed by the results of massive glacial action. In a sense Yosemite is the future of where he had been the previous week--- a part of Alaska where the ice is 1,000 feet thick, with mountain peaks just visible above the glacial carving. Still further in the past is a classic end-of-the-world---an Ice Age. Childs sampled what that is like with an extended stay on the Greenland ice cap, where all there is for hundreds of miles is ice, sky, and wind. And numbing cold. The ice is 5,000 feet thick, moving under his camp at 1 foot a day, eventually calving off into enormous icebergs.

He was in Greenland with a chaos scientist studying climate change, who noted that complex systems like climate sometimes change suddenly, and that’s when you can’t predict what will happen next.

“I would like to backpack on Mars,” said Childs. For the local equivalent he hiked across the Atacama Desert in northern Chile, where it never rains. It’s been a desert for 150 million years. You walk across nothing but salt so hard it pings like steel. The sun blasts you all day and at night the water in your pack freezes solid. “You walk for days and you don’t see a single living thing, you’re on a dead planet, and then it gets really strange because pink flamingoes come flying in over your head. They’re there to strain brine shrimp out of water sources. You’re at the end of the world and there are flamingoes! You think, 'Yeah, that’s what this planet is about.'”

To experience a world without biodiversity he hiked for days in cornfields in Iowa, where 90 percent of the state is monocrop corn and soybeans. Yet it took just two years for tallgrass prairie to be re-established in a site where corn growing was stopped.

In the lava fields of Hawaii he got a sense of planetary beginnings when the magma escapes, flowing like liquid incandescent metal, and everything starts over. Life is reseeded from what are called kipukas, bits of forest missed by the lava. Plunging into some new forest densely regrown on recent lava, he was instantly lost, buried in an orgy of jungle vegetation, no animals yet, and he realized that “The force of the living is more cunning than any devastation, ready to explode on whatever it touches.”