Today, most scientists agree that climate change, with its dire implications, is the most urgent challenge facing humankind. Global-warming deniers have taken on the taint of 9/11 conspiracy theorists. Yet, Suzuki admits, we’ve made surprisingly little progress in persuading the public, and the politicians, that the path we’re on ends in disaster in a very few generations. The growth of carbon dioxide emissions, mainly from fossil fuel, remains a threat. Carbon in the atmosphere keeps accumulating. In 2014 the average global temperature was the highest ever recorded.