James Hansen's Climate Warning, 30 Years Later
“The greenhouse effect has been detected, and it is changing our climate now.”
Those were the words of James Hansen, then the director of the NASA Goddard Institute for Space Studies, to the U.S. Senate Energy committee on a sweltering June day in 1988. Thirty years on, the overwhelming consensus from scientists is that Hansen was right—and most would say that far too little has been done since to address the threat.
1988 turned out to be the hottest year since modern instrumental records began in the 19th century. That mark has since been broken, in 1990, 1998, 2010, 2014, 2015 and 2016. The global average temperature has not gone up quite as much as Hansen predicted—among other things, 30 years ago scientists lacked the sophisticated instruments, accumulated data and vast computing power informing today’s climate models—but he was remarkably close given the limitations, and was dead right on the overall trend.
A wide variety of media marked the anniversary. Justin Gillis, writing in The New York Times, noted that, among the confounding factors in 1988, Hansen’s models assumed that we would continue emitting refrigerant gases that contributed mightily to global warming. The following year, the nations of the world agreed to control those gases—”proof that scientific warnings, if taken seriously, can be acted upon at a worldwide scale,” said Gillis. “So while his temperature forecast was not flawless, in a larger sense, Dr. Hansen’s 1988 warning has turned out to be entirely on target,” said Gillis Sen. Sheldon Whitehouse (D-R.I.) recounted Hansen’s testimony in a 17-minute speech on the Senate floor, noting that “30 years of added science” have proved just how right Hansen was.”
Much of the press coverage hinged not so much Hansen’s prescience—that is old news—but on increasing hostility in the United States to scientific observations, and the actions they might suggest. The Associated Press’s Seth Borenstein noted that “America’s political climate may have changed more than the Earth’s over the past three decades.” As late as 2008 the Republican Party platform called for action against climate change; today, the U.S. administration has exorcised those very words from web sites and we are the sole nation on the planet to withdraw from the Paris climate accords. Predictably, the Wall Street Journal marked the anniversary with an opinion piece by two associates of the libertarian Cato Institute claiming that Hansen, and all the major scientific bodies of the world including the Intergovernmental Panel on Climate Change have been wrong all along. “It’s time to acknowledge that the rapid warming he predicted hasn’t happened,” they write. Their recommendation for action: “a lukewarm policy, consistent with a lukewarming planet.”
Hansen himself has spoken up in an op-ed in the Boston Globe. “My advice to young people is to cast off the old politics and fight for their future on technological, political, and legal fronts,” he writes. He adds: “It will not be easy.”
James Hansen wishes he wasn’t so right about global warming Associated Press