Our Biggest Test Yet

Bill McKibben would never get a casting call to play the part of a revolutionary. He wears sensible glasses, his middle name is “Ernest,” and he ends his phone calls with “God bless.” After all, the international climate change rabble-rouser never planned to become an international climate change rabble-rouser. But as the author of one of the first books to describe the effects of global warming, McKibben soon realized we needed a major response to the crisis. In 2008 he cofounded 350.org, named after 350 parts per million, which is believed to be the upper limit for safe carbon dioxide concentration in earth’s atmosphere. The organization has grown into a grassroots collaboration of people working to end dependence on fossil fuels, and there’s been a 350-related event in every country around the world except for North Korea.

Now approaching sixty, McKibben isn’t slowing down, unless he’s crashed his bike (we’ll get to that in a moment). He’s received the Gandhi Peace Award, a Guggenheim fellowship,