A climatologist, activist, and one of the first to study global climate change, Hansen directs the Program on Climate Science, Awareness, and Solutions at Columbia University’s Earth Institute. Fossil fuels provide a remarkably dense, convenient, form of energy. Their discovery powered the industrial revolution, spurred the elimination of slavery, and raised the standard of living of half the world. Unfortunately, fossil fuels also have consequences via their effects on human health and climate, consequences that are delayed and potentially devastating for young people if they are not addressed.

Also a former director of the NASA Goddard Institute for Space Studies, Hansen is best known for his testimony on climate change in the 1980s that helped raise awareness of global warming. He is a member of the U.S. National Academy of Sciences and has received numerous awards, including the Sophie and Blue Planet Prizes. Hansen is recognized for speaking truth to power and for outlining actions needed to protect the future of young people and all species on the planet. Hansen may be joined by his granddaughter, Sophie Kivlehan, a plaintiff in the climate lawsuit brought by Our Children’s Trust against the US government.