As climate change continues to stir concern and debate around the world, Prof. Michael Greenstone knows the importance of using his research to better explain the connection between the environment, health and global energy. The challenge for he and his colleagues at the Energy Policy Institute at the University of Chicago (EPIC) is waiting for others to put that information into action.   “I’m in charge of my research, and I’m not in charge of the world,” Greenstone said of Big Brains. “What we can do as scientists is make sure that the information is being articulated as clearly and in an accessible way as possible. It’s ultimately up to societies to judge what they’re going to do with it.”   Greenstone’s work has already had global impact. He and his EPIC colleagues developed a new pollution index that found air pollution cuts the global life expectancy by nearly two years. The Air Quality Life Index establishes air particulate pollution as the single greatest threat to human health globally.   On this episode of Big Brains, the environmental economist discusses how the global energy challenge is one of society’s most important problems and something he calls “the social cost of carbon”—the most important number you’ve never heard of when it comes to climate change.   Subscribe to Big Brains on Apple Podcasts, Stitcher and Spotify, and rate and review the podcast.