SuperFreakonomics on global warming

The new “SuperFreakonomics” book has attracted some passionate criticism from climate scientists and a community of writers, researchers and scholars for a chapter on global warming. Co-authors Stephen Dubner and Steven Levitt reject the idea that reducing carbon emissions should be the sole focus for addressing global warming, and dive into an array of bold ideas for “geoengineering,” which would allow people to directly change temperatures on Earth. Stephen Dubner joins us to explain and defend the Freakonomics approach.