Editorial viewpoints from Climate Central's writers and editors.

Jim Hansen, Climate Bulldog: Still Going Strong at 70

By Michael D. Lemonick

After Al Gore, James Hansen is probably the man climate skeptics most love to hate. Unlike Gore, Hansen is an actual scientist, at NASA’s Goddard Institute for Space Studies in New York (it’s located above the restaurant that used to be featured in Seinfeld). It was Hansen who single-handedly put climate change on the national radar when he testified before Gore’s committee in 1988 during a killer heat wave, saying “. . . the evidence is pretty strong that the greenhouse effect is here.”

Nearly a quarter of a century later, Hansen is more deeply immersed in the issue of climate change than ever. He’s still writing scientific papers — a new one, titled “Public Perception of Climate Change and the New Climate Dice,” which argues that the notable recent increase in climate extremes is no accident, has been submitted to Proceedings of the National Academy of Sciences.

Credit: Mari Monrad Vistven

He’s also come out of the ivory tower to join protests against coal-fired power plants (he was arrested outside the White House) and the Keystone XL pipeline (another arrest, same place). And he’s speaking out wherever and whenever he can about the dangers of climate change, along with our responsibility to do something about it — in a recent TED talk, for example, and in an even more recent interview with The Guardian, in which he declared that human climate change is a “great moral issue” on a par with slavery — an “injustice of one generation to others.”

It was Hansen’s 2008 paper suggesting 350 parts per million (ppm) of CO2 in the air as the level we should aim for that launched the activist organization 350.org (we’re already approaching 400 ppm, with no appreciable emissions slowdown).

No wonder skeptics dislike the guy, and go out of their way to try and shoot down his scientific work. So far, it hasn’t worked out so well. At around the same time Hansen gave his 1988 Congressional testimony, he put together a projection of future temperature rise — a projection skeptics have jumped on as being an “astounding failure.” Not really, though.

Recently, the bloggers at RealClimate.org have unearthed an even earlier Hansen projection, from a paper (pdf) published in Science all the way back in 1981. At the time, the authors of a recent post on the paper point out, global temperatures were actually cooler than they’d been since the early 1940’s, thanks to the shadow cast by clouds of pollution — and yet, write the authors, “[Hansen and his co-authors] confidently predicted a rise in temperature due to increasing CO2 emissions.” In fact, they underestimated the temperature increase we’d see 2010 by about 30%, so Hansen was indeed wrong. He was too conservative. But the authors continue

“. . . a projection from 1981 for rising temperatures in a major science journal, at a time that the temperature rise was not yet obvious in the observations, has been found to agree well with the observations since then, underestimating the observed trend by about 30%, and easily beating naive predictions of no-change or a linear continuation of trends. It is also a nice example of a statement based on theory that could be falsified and up to now has withstood the test. The ‘global warming hypothesis’ has been developed according to the principles of sound science.”

Some of his colleagues in the mainstream climate-science community are reluctant to go as far out on a limb as Hansen. They aren’t comfortable crossing the line that separates science from activism, although everyone agrees that Hansen keeps his activist views out of his scientific work, which is why his science is still taken very seriously. They sometimes challenge his scientific work as well — not everyone agrees with the interpretation of evidence that led Hansen to declare 350 ppm as the proper target for atmospheric CO2 — but every top scientist, including Einstein, has had his or her work challenged. It’s how science works.

At age 70, James Hansen shows no evidence of slowing down. As the RealClimate post makes clear, he’s been doing impressive science since 1981, at least, and he’s still a prolific, highly respected climate scientist. He’s also a vigorous spokesman for humanity’s obligation to do something about our greenhouse gas emissions, and soon. Skeptics might hate him, but he’s not going away.

« Commentary


By dan in illinois
on April 9th, 2012

I understand that Dr. Hansen has a right, under the constitution, to advocate for positions that I disagree with but I cannot understand why I, as a taxpayer, have to pay him to do so.

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By David Matz, PhD (Chadds Ford/PA/19317)
on April 9th, 2012

I know that Hansen’s projections from 1988 to 1997 were in the correct direction, but off by a minor factor of 4.  But no one talks about the projections that model had beyond 1997. We now have a lot more data to evaluate the quality of the 1988 model.  Let’s talk about it.

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By Kevin Buterbaugh
on April 9th, 2012

To “Dan in Illinois”,

What makes you think you’re paying him?  He does his science - untainted by politics - during the day (and yes, as a taxpayer you do pay him for that).  His activism is done on his own time and you therefore do not pay him for that…


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By Andrew Revkin (Garrison, NY, 10524)
on April 9th, 2012

My favorite section of that paper is as follows:

Political and economic forces affecting energy use and fuel choice make it unlikely that the CO2 issue will have a major impact on energy policies until convincing observations of the global warming are in hand. In light of historical evidence that it takes several decades to complete a major change in fuel use, this makes large climate change almost inevitable. However, the degree of warming will depend strongly on the energy growth rate and choice of fuels for the next century.

Thus, CO2 effects on climate may make full exploitation of coal resources undesirable. An appropriate strategy may be to encourage energy conservation and develop alternative energy sources, while using fossil fuels as necessary during the next few decades.

The climate change induced by anthropogenic release of CO2 is likely to be the most fascinating global geophysical experiment that man will ever conduct. The scientific task is to help determine the nature of future climatic effects as early as possible. The required efforts in global observations and climate analysis are challenging, but the benefits from improved understanding of climate will surely warrant the work invested.

More here: A Fresh Look at How Humans Are Loading Climate ‘Dice’: http://nyti.ms/HVzLRH

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By Paul (Princeton NJ)
on April 10th, 2012

Even as Hansen compares “climate change” to slavery, he wonders why public interest goes down, down, down as shrill alarmism goes up.

By the way, you folks at Climate Central may need a bit of affirmative action.  Your “who we are page” has about thirty faces, all of them equally pale.  Are there no alarmists of color?  If you weren’t on the politically correct side of things, the EEOC might be on your case.

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By Annemarie (Valparaiso, IN)
on April 22nd, 2012

To “Dan in Illinois”

While I certainly understand that you do not want your taxes supporting something you yourself do not believe or believe in, please consider how painful it has been for many of your fellow citizens to see their tax money go to wars and oil company subsidies just to name two obvious examples. 

On the subject of climate “change”—even if you do not believe the CO2 science, there are many qualified people who see facts where you see fabrication and I do not understand why a thoughtful person would completely dismiss their concerns.  Even if the people you call “alarmists” are wrong (perhaps they are the Paul Reveres of our day), why take a risk with the only planet we have to leave to future generations?  Even if it is a small chance (in your eyes) that climate changes are caused by humans, if we can DO something about it, should we not do so?  Is this not a moral question as to what we leave for future generations?  If we want to think selfishly and short term, we can also consider that a greener economy could certainly also create many good jobs.

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