NASA climate scientist James Hansen, outspoken advocate, to leave government

He plans to take a more active role in lawsuits challenging the federal and state governments over their failure to limit emissions, for instance, 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 an interview. 

Hansen warned Congress in 1988 testimony about the threats of global warming.

He has blended scientific research and, later in his career, activism around climate change, such as getting arrested in protest of the Keystone XL oil sands pipeline.

Hansen told The Washington Post that he’s leaving NASA “so that I can spend full time on science, drawing attention to the implications for young people, and making clear what science says needs to be done.”

The Times reports that Hansen hasn’t ruled out setting up an institute or taking an academic position to further his work.

The paper also delves into the controversies that have surrounded Hansen, noting, “Even some of his allies consider him prone to rhetorical excess and to occasional scientific error.”