GLEICHSCHALTUNG! Next Time You Visit a National Park, You Might Get a Lecture on Climate Change.

Ettling has spent his summers working as a park ranger at Crater Lake National Park in Oregon for nearly a decade. He is on a mission to teach visitors that man-made global warming is real. But climate change can be a touchy subject. So Ettling devised a strategy. When a park visitor casts doubt on global warming, he makes an appeal to their pocketbook.

“I try to shift the conversation away from polar bears and ice caps,” Ettling says. “I tell people there are a lot of things they can do to save money on their electric bill that will also help the environment. Usually, I can get through to them that way.”

Do they pitch ObamaCare, too?