Climate Scientist Hansen Turns Activist, Advocates 'Fee' on Carbon Pollution

James Hansen, the former NASA climate scientist who first brought climate change to the attention of Congress in the 1980s, stepped down as head of the agency's Goddard Institute for Space Studies last month. That hasn’t stopped him traveling the globe to lobby for climate protection measures, while remaining an adjunct professor for Earth and Environmental Studies at Columbia University.

I caught up with Hansen in London last week. He was in Europe to lobby politicians to classify fuels from oil sands as more polluting than conventional fossil fuels. A Congressional Research Service study published in March estimates that Canadian oil sands are 14 percent to 20 percent (pdf) more carbon intensive than conventional crude.