A recent Pew survey found that 48% of Americans are still unconvinced that global warming is happening and that human activity is causing it. How can this high level of doubt persist in the face of overwhelming scientific evidence? Our guest today on Sea Change Radio is Naomi Oreskes, co-author of the book Merchants of Doubt. As the title suggests, Oreskes believes that seeds of doubt have been planted quite intentionally. The same playbook that was used by tobacco companies to hoodwink the public is now being applied to climate change. The book Merchants of Doubt inspired a recent documentary film by the same name. Oreskes, who teaches the history of science at Harvard, gives us a sneak peek of the film and tells us about some of the characters who have turned large-scale deception into an art-form and an industry.