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Climate Scientist James Hansen Leaves NASA: Reactions

James Hansen

Chesapeake Climate

James Hansen, perhaps the world's most prominent and outspoken climate scientist, had told reporters in recent years that his retirement was coming. Yesterday, The New York Times reported that the 72-year-old researcher has made it official and will leave his job at a NASA research institute after 46 years to pursue climate activism and litigation full-time.

The move marks a new turn in a storied and tumultuous career that has transformed Hansen, as environmental scientist Roger Pielke Jr. of the University of Colorado, Boulder, puts it:

[F]rom staid government bureaucrat -- clean shaven in a blue suit to a stylish icon, complete with signature hat and Amish beard -- to passionate advocate who no longer wants to work for government but seeks to change it.

Working from a quixotic NASA research facility adjacent to Columbia University whose quiet hallways felt more like an academic outpost than a government lab, Hansen's voluminous research career spanned everything from work on Venus, his first atmospheric science quarry, to creating one of the first climate models for Earth. Later, he delved deeply into applied energy research and the impacts of climate change. In 1988, he rose to public notice with testimony before Congress that warned of the implications of rising concentrations of carbon dioxide in the atmosphere. And equal to his scientific legacy may be his decision, made roughly a decade ago, to begin to speak out forcefully for "the survival of humanity itself" in the face of "government inaction and greenwashing," as he put in his 2009 book Storms of My Grandchildren.

The news of Hansen's retirement set Twitter and the Web world buzzing with reaction that highlighted the impact that the researcher has had within and far beyond the scientific community.

Climatologist Don Wuebbles of the University of Illinois, Urbana-Champaign, tells ScienceInsider:

Jim has been an important scientist on climate for his career. Not only was he one of the early climate modelers, but he's shown insights in a variety of areas, from climate sensitivity to a whole range of basic insights about the climate system. I thought his recent work by him and his team, for example, on extreme events, showed great insight.

From prominent activists:

In 2007, McKibben—who heads the nonprofit group, which advocates for policies to reduce emissions of greenhouse gases—had asked Hansen to give him a target that the world should try to achieve for the atmospheric concentration of carbon dioxide, the main warming gas. The current concentration is about 394 parts per million (ppm), and McKibben had considered naming the group "450," after a concentration goal some researchers say would help protect the planet from climate change's most adverse impacts. But Hansen's answer, expressed in a paper entitled "Target Atmospheric CO2: Where Should Humanity Aim?" was 350 ppm—and so was christened, which has become the biggest and most prominent global activist network on climate policy. It has helped organize numerous demonstrations; at some, protestors—including Hansen—have been arrested.

Emmy Burns, a student activist with the University of Wisconsin, Madison, student chapter of 350, tells ScienceInsider that Hansen's retirement leaves mixed emotions:

I'm ultimately grateful to him, especially that's he's been willing to speak out and be heard. His authority on this issue has meant a lot to our movement. … But it's disheartening that he has to remove himself from a federal position to advocate on climate change. Government exists, in theory at least, to serve the public's best interests.

Hansen's forays into policy, including meetings with top ministers and elected leaders around the world, have often been controversial. In 2009, for example, he advocated against the cap and trade systems that the Obama administration and its overseas partners were trying to install here and globally, calling it "a market-based approach that has been widely praised but does little to slow global warming or reduce our dependence on fossil fuels … [allowing] polluters and Wall Street traders to fleece the public out of billions of dollars."

That view drew fire from economist and columnist Paul Krugman:

James Hansen is a great climate scientist. … Unfortunately, while I defer to him on all matters climate, today's op-ed article suggests that he really hasn't made any effort to understand the economics of emissions control. And that's not a small matter, because he's now engaged in a misguided crusade against cap and trade, which is - let's face it - the only form of action against greenhouse gas emissions we have any chance of taking before catastrophe becomes inevitable.

In recent years, Hansen has focused his attention on legal battles involving climate issues, such as suits against fossil fuel developments and defending activists arrested while protesting fossil fuel facilities. Defense attorney Mike Schwarz of London law firm Bindmans tells ScienceInsider:

Jim Hansen's contribution to the defense of climate change campaigners in the [United Kingdom] courts has been unique and invaluable. Juries have heard - and been deeply moved - by his first hand authoritative testimony to the dangerous trajectory the business-as-usual model to CO2 emissions is taking mankind and the planet. Jim Hansen gave evidence for 10s and 10s of campaigners in the UK - all of whom have been vindicated in their actions by the criminal justice system. This is in no small measure the result of Jim Hansen's selfless efforts. His grandchildren can be proud that he has done all he can to try to preserve their, and later generations', future.

Those efforts, though, won Hansen few fans among opponents of action on climate change. From skeptic blogger Marc Morano:

Celebrate! It's A Happy Day for Science! Hansen's sad legacy will serve as a cautionary tale for future scientists. Hansen chose ideology, activism, stagecraft and handcuffs over science. He will be sorely missed by global warming skeptics, as he made our life so much easier by just being himself. NASA & Science deserved much better than James Hansen.

Even 2 years ago, some of Hansen's most ardent fans—such as David Roberts of Grist—were uneasy about his political activities.

Now, Roberts has updated his thoughts:

Others doubted Hansen's punch will be diminished without a government job. Bud Ward wrote on the Yale climate media forum:

Jim Hansen and his message, at this point, aren't going anywhere. Not anywhere, that is, that will diminish the power of his evidence, the volume of his voice, or the deep-seated passion of his convictions, so many of them firmly entrenched in the peer-reviewed evidence of which he was a frequent author.

*Updated 11:40 a.m. on 4 April: This item has been updated to clarify the timing of Roberts' comment and include his latest thinking, which came out after the piece was published.