This past weekend the National Park Service (NPS) hosted me at Grand Canyon, and I gave the keynote talk for its Earth Day celebration to a crowd that hailed from all over the world. It wasn’t the only vertiginous aspect of the trip. I hiked down into the canyon one day with rangers Marty Martel and Pam Edwards, and got a new appreciation for the word “steep.” Another day I took a long stroll along the rim, transfixed by new views at every frequent turn. The truly grand f

Crazy gorgeousness, check. At Duxbury Reef in Bolinas early yesterday morning, a super low tide pulled back the covers not only on all those squirmers and clingers making colorful hay in the kelp, but revealed the geological formation that makes this reef the biggest rocky intertidal in the West. Duxbury is right at the conjunction of two major plates, the Pacific and the North American. You can visibly see where one big time-frame era is laid against another. The reef pa