James Hansen became the face of climate science 35 years ago with high-profile appearances before Congress, calling attention to global warming. Hansen is widely respected for his research on greenhouse gas emissions and warming, and as director of the NASA Goddard Institute for Space Studies at the time, his words carried additional authority. But Congress did not act on climate change in the ’80s or the ’90s.
Hansen stepped up his warnings, urging immediate reductions in the greenhouse gas emissions that cause climate change and joining climate protests. He even got arrested during acts of civil disobedience outside a West Virginia coal mine in 2009 and near the White House in 2011.
Now an adjunct professor at Columbia University’s Earth Institute, where he directs the Program on Climate Science, Awareness and Solutions, Hansen is issuing a new warning about climate change—as well as a controversial call for action.
Hansen and 17 co-authors argue in a new peer-reviewed paper that warming is accelerating beyond what many climate models show, and that cuts to greenhouse gas emissions—while urgently needed—will not be sufficient to avoid very dangerous levels of warming. He thinks a form of planet-wide geoengineering to block some of the sun’s incoming rays will probably be needed.