Historian of science Thomas Kuhn warned of “scientists … behav[ing] differently” and experiencing “pronounced professional insecurity” when one of their long-held beliefs comes under increasing pressure from new science (The Structure of Scientific Revolutions. 1962. Reprint. Chicago: University of Chicago Press, 1970, pp. 24, 67–68).
Is this the case with NASA scientist James Hansen, who (in the opinion of his many and growing critics, and even some friends) keeps putting his foot where his mouth is?
In an interview just published in The Guardian, he states that President Obama has “four years to save the earth.” This latest incarnation of his great climate alarm is mostly based on a projected rise in sea level rise, a scenario that our Chip Knappenberger analyzed critically in his post yesterday.
Hansen’s latest is related to the ten-year alarm he gave in 2006, in a piece in the New York Review of Books:
We have at most ten years—not ten years to decide upon action, but ten years to alter fundamentally the trajectory of global greenhouse emissions.
So in two and a half years, ten years has become four years, the exact length of Obama’s first term.
On the political front, Hansen has stated:
CEOs of fossil energy companies know what they are doing and are aware of long-term consequences of continued business as usual. In my opinion, these CEOs should be tried for high crimes against humanity and nature.
He has also analogized conventional electricity-generation to the Holocaust:
If we cannot stop the building of more coal-fired power plants, those coal trains will be death trains — no less gruesome than if they were boxcars headed to crematoria, loaded with uncountable irreplaceable species.
Hansen has also defended criminal obstruction at UK coal plants.
Back to the science. The climate mini-alarms concerning hurricanes, sea level rise, ocean circulation disruption, and so forth, are in open scientific dispute. Global warming has stalled, and 2009 will put the trusted warming projections of climate models out of bounds, if the warming does not resume noticeably.
Yet now more than ever, Dr. Hansen is CERTAIN that his high-sensitivity estimate is correct (“Nailed–It’s 3C for 2x CO2,” Slide 15 in a recent Hansen presentation states).
Many climate scientists disagree with Hansen, including the full range of “skeptics,” from Richard Lindzen (below 1C) to Spencer, Christy, and Michaels (between 1C and 2C), to others.
Even members of the “mainstream” disagree with Hansen. For example, Gerald North at Texas A&M has projected 2C for as long as I have known him. Not that his self-described “toy model” is definitive, but intuition from seasoned veterans like North might well be better than climate models that the IPCC itself admits are problematic (“The set of available models may share fundamental inadequacies, the effects of which cannot be quantified,” p. 805).
Is Hansen a scientist behaving strangely, as his increasing bets on climate alarmism are contradicted by Mother Nature? Only the future will tell. But given the inability of the political process to address his alarm, the rest of us may want to shift public-policy course to favor adaptation to climate change rather than (ineffectual) mitigation. Resources are scarce, and tradeoffs must be made.