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From KQED.

Music from KQED. From KQED. From KQED in San Francisco, I'm Mina Kim. Coming up on forum, The Deep Sea. Writer and

aquatic explorer Susan Casey calls it nature's motherboard, absorbing heat, buffering excess carbon,

driving our climate, and regulating the Earth's geochemistry. It's also home to mountains taller

than the Swiss Alps and populated by a cast of, quote, marvelous weirdos,

creatures that have eyes in the middle of their backs, two mouths, three hearts, transparent heads.

And Casey knows this with her own eyes, from diving in deep sea submersibles.

We learn about her journeys to The Underworld, the title of her new book, Join us.

Welcome to Forum. I'm Mina Kim. The Deep sea often looms as a threat or a cautionary tale,

writes journalist Susan Casey, as if the deep were too remote, too frightening, too ugly to be lovable.

But what if, she asks, we have it upside down? What if the deeper you go, the more astonishing everything becomes?

That's a question that's driven Casey at deep-sea obsessive her entire career.

...