by Mitch Kokai
Senior Political Analyst, John Locke Foundation
Think the world knows enough about global warming and climate change, and it’s time to shut down debate on the topic? Perhaps you should read Rupert Darwall‘s thoughts on the topic in a City Journal article.
Climate-change science is “settled,” say proponents of anthropogenic (human-induced) global warming, or AGW: the earth is getting warmer, and human activities are the reason. The Intergovernmental Panel on Climate Change (IPCC), set up by the United Nations in 1988, has issued five assessment reports since its founding. In its most recent, in 2013, the IPCC stated that it was now “95 to 100 percent certain” that human activities—especially fossil-fuel emissions—are the primary drivers of planetary warming. Frequent news reports—such as the story of the melting of the West Antarctic Ice Sheet, a process that some scientists say is irreversible—seemingly confirm these conclusions.
And yet, highly credentialed scientists, including Nobel Prize–winning physicist Ivar Giaever, reject what is often called the “climate consensus.” Giaever resigned from the American Physical Society in protest of the group’s statement that evidence of global warming was “incontrovertible” and that governments needed to move immediately to curb greenhouse-gas emissions. Sixteen distinguished scientists signed a 2012 Wall Street Journal article, in which they argued that taking drastic action to “decarbonize” the world’s economy—an effort that would have major effects on economic growth and quality of life, especially in the developing world—was not justified by observable scientific evidence. And, like Giaever, they objected to the notion of a climate consensus—and to the unscientific shutting down of inquiry and the marginalization of dissenters as “heretics.” Most recently, renowned climate scientist Lennart Bengtsson stepped down from his post at a climate-skeptic think tank after he received hundreds of angry e-mails from scientists. He called the pressure “virtually unbearable.”
Another dissenter, the American atmospheric physicist Murry Salby, has produced a serious analysis that undermines key assumptions underpinning the AGW worldview. His work and its reception illustrate just how unsettled climate science remains—and how determined AGW proponents are to enforce consensus on one of the great questions of our age. …
… Unsurprisingly, the consensus view on the carbon cycle remains that human CO2 emissions are “virtually certain” to be the dominant factor determining current CO2 concentrations. Updating the global-warming catechism in a joint 2014 paper, the National Academy of Sciences and the Royal Society declared: “Continued emissions of these gases will cause further climate change, including substantial increases in global average surface temperature.”
If they adhered to the standards established three centuries ago during the Scientific Revolution, the academies would not be able to make such definitive claims. Nineteenth-century astronomer and philosopher of science John Herschel demanded that the scientist assume the role of antagonist against his own theories; the merits of a theory were proved only by its ability to withstand such attacks. Einstein welcomed attempts to disprove the theory of general relativity. “No amount of experimentation can ever prove me right; a single experiment can prove me wrong,” he is said to have declared. Because in science, the philosopher Karl Popper reasoned, we cannot be sure what is true but we can know what is false, truth is approached by discarding what is shown to be false. Popper articulated the principle of falsifiability, distinguishing scientific theory from the pseudosciences of Marx and Freud, whose followers, he noted, found corroboration wherever they looked.
The IPCC and other leading scientific bodies also appear to follow a prescientific injunction: “Seek and ye shall find.”