Too hot to handle
Recent efforts to censor Jim Hansen, NASA's top climate scientist, are only the latest. As his message grows more urgent, we ignore him at our peril.
JIM HANSEN, the director of NASA'S Goddard Institute for Space Studies, is a dangerous man. Not a brash man or a rebel-I remember interviewing him many years ago, and when I asked him what he did to relax, he replied, ''mow my lawn." He's spent his whole career on the NASA payroll, but never looked up at the beckoning stars, at least professionally. Instead, from a floor of offices above Tom's Diner, of ''Seinfeld" fame, on New York's Upper West Side, he's fixed an unwavering gaze on our home planet and the narrow envelope of atmosphere that surrounds it.
It's in that process that he's acquired the data, including one of the most comprehensive and accurate temperature records for the entire globe, that makes him so unsafe-data he's repeatedly tried to spread to the world, but always against resistance, mostly from politicians but also from scientists.
The latest dust-up came last week, when The New York Times reported that the public affairs staff at NASA was trying to censor Hansen's contacts with journalists-not to mention postings on his website, his lectures, and his future papers-after he told the American Geophysical Union, in a speech on Dec. 6, that 2005 had been the warmest year on record. Not that they acted out of any untoward motive, NASA officials insist, just to make sure that he wasn't misquoted.
Hansen has had to deliver unpopular news before, and he's always persisted-and this time, as usual, he managed to turn the gag order into a megaphone. In fact, if you follow the thread of the controversies that have marked Hansen's career, you can understand how the idea of global warming first came to light, how it's been resisted, and why we seem now to be entering into the most dangerous era of all, when theory turns ever more quickly into reality.
. . .
In the late 1970s, global warming was something that very few scientists thought about and almost no politicians took seriously. Hansen, however, then a newly minted PhD arriving in New York from the Midwest, had begun to build his first global climate model, an immensely complex computer simulation of the planet's climate that allows its user to, say, add a layer of carbon dioxide to the atmosphere and see what happens. What happens, as he put it in a paper in Science, is that the temperature goes up, a lot: He predicted that ''the continuing increase in fossil fuel use would lead to about 4.5-degree Fahrenheit global warming by the end of the twenty-first century."
The incoming Reagan administration, unfortunately, did not want to hear that-and so they cut his funding to the bone, forcing him to lay off most of his NASA staff. Still, he'd raised the issue, gotten it on the front pages of the papers for the first time, and-since he had the best model of the world's climate anywhere-he eventually got a new round of funding.
The next time he had something to say, he didn't choose a scientific journal. It was June 1988, and the country was unusually hot-the Mississippi River was so dry that barges were unable to navigate the shallow waters. A congressional committee asked him to testify, and he did. In his allotted 15 minutes, in his usual mild voice, he predicted that 1988 would set a new global temperature record, and indeed that he was ''99 percent confident" that it was due to the greenhouse effect. As he left the hearing, he told reporters: ''It's time to stop waffling so much and say that the greenhouse effect is here and is affecting our climate now."
That sound bite rankled the Republican administration (which tried to edit his further testimony, with about as much success as NASA had last week) but it also angered his scientific peers. He'd broken the scientific code, talked in real-world terms, ''gone beyond the data." Daggers were drawn, and they were used. Mark Bowen, in his fine recent history of climate science, ''Thin Ice" (2005), describes the next meeting of the world's climatologists as a ''get-Hansen session." Scientists, accustomed to publishing in peer-reviewed journals, speak in nuances and caveats. To say ''I'm 99 percent certain" goes against the academic grain.
Hansen, of course, understood this. He's spent his whole career in academic conferences and scientific meetings. But he also knew that the rest of the world-the audience that needed to understand our predicament-doesn't speak that way.
The professional criticism stung him, but it had clearly been worth it. Every newspaper and every newsmagazine published long reports on the subject-within a week, ''greenhouse effect" had gone from a scientific term to a media buzzword. By year's end Time had named ''our endangered earth" its ''planet of the year," and the elder George Bush, running for president, was promising to ''fight the greenhouse effect with the White House effect"-an applause line, unfortunately, which didn't lead to much in the way of policy. More importantly, the fear Hansen sparked led to almost bottomless federal research budgets for his fellow scientists, and by 1995 they had concluded he was correct: The planet, said the world's foremost body of climatologists, the Intergovernmental Panel on Climate Change, was heating up and people were the cause.
In the rest of the developed world, that was enough to get policy makers working on projects like the Kyoto Treaty. But here, where all the crucial science had been done, the prospect of grappling with our fossil fuel addiction was simply too daunting for either the Clinton administration, which at least recognized the problem, or the George W. Bush White House, which turned its back. When one Environmental Protection Agency document dared to mention the possibility of a warming planet, Bush dismissed it as a product of ''the bureaucrats."
. . .
And so we go on burning ever more fossil fuel, and the earth keeps getting warmer-as Hansen's monthly monitoring of 10,000 temperature gauges around the planet makes depressingly clear.
But the new high temperature record isn't the real reason Hansen is so agitated right now, nor the reason the Bush administration would like to silence him. Instead, it's the messages about future change that his computer climate models keep spitting out.
Those models reveal a miserable situation at present, but a dire one in the years ahead. In his December speech to the Geophysical Union, he noted that carbon dioxide emissions are ''now surging well above" the point where damage to the planet might be limited. Speaking to a reporter from The
''It's not something we can adapt to," he continued. ''We can't let it go on another 10 years like this."
And that's what makes him so dangerous now. He's not just saying that the world is warming. He's not just saying we're the cause. He's saying: We have to stop it now. Not wait a few decades while
The president, just this week, said that we've become ''addicted to oil," which is a little as though Abe Lincoln suddenly noticed the South had slaves. Bush's package of fixes-a little money for nuclear, for clean coal, for wind power-goes in the right direction, but so slowly as to be a gesture, not a policy. If we want to keep a semblance of the planet we were born on to, we have to act decisively, expensively, quickly, and now.
You can argue with Hansen if you want. But you better bring a pretty big data set with you. He's been right so far.
Bill McKibben, a scholar in residence at Middlebury College, is the author of ''The End of Nature" and eight other books on environmental topics. 