James E. Hansen, one of the best known climate scientists in the world who issued the clearest warning of the 20th century about the dangers of global warming, has retired from NASA this week.
He also plans to take a more active role in lawsuits challenging the federal and state governments over their failure to limit emissions, as well as in fighting the development in Canada of a particularly dirty form of oil extracted from tar sands.
“As a government employee, you can’t testify against the government,” he said in the New York Times .
Hansen has said that at 72 he feels a moral responsibility to step up his activism
“If we burn even a substantial fraction of the fossil fuels, we guarantee there’s going to be unstoppable changes” in the climate of the earth, he said. “We’re going to leave a situation for young people and future generations that they may have no way to deal with.”he said in an interview with the New York Times.
“He’s done the most important science on the most important question that there ever was,” said Bill McKibben, a climate activist who has worked closely with Dr. Hansen.
In worldwide temperature records going back to 1880, the 19 hottest years have all occurred since Dr Hansen's first testimony.
One notable fight in Dr. Hansen’s career bwas in late 2005, when a political appointee in the administration of George W. Bush began exercising control over Dr. Hansen’s statements and his access to journalists. Dr. Hansen took the fight public and the administration finally backed down.
In recent years Dr. Hansen has been lending his support to fights against individual fossil fuel projects. he went to a student protest against coal protest in 2009, and that was where he was arrested for the first time. That fall he was cited again after sleeping overnight in a tent on the Boston Common with students trying to pressure Massachusetts into passing climate legislation.
Dr. Hansen says he senses the beginnings of a mass movement on climate change, led by young people.
“At my age,” he said, “I am not worried about having an arrest record.”