An Unsettling Climate
Global-warming proponents betray science by shutting down debate.
http://www.city-journal.org/2014/24_3_global-warming.html
Summer 2014
EDWARD FRAZER/CORBIS
Scientist Murry Salby argues that a key factor behind rising temperatures is heat exchange between the atmosphere and the ocean.
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.
In April 2013, concluding a European tour to present his research, Salby arrived at Charles de Gaulle Airport in Paris for a flight back to Australia, where he was a professor of climate science at Macquarie University. He discovered, to his dismay, that the university had canceled the return leg of his nonrefundable ticket. With Salby stranded, Macquarie then undertook misconduct proceedings against him that swiftly culminated in his dismissal. The university claimed that it did not sack Salby for his climate views but rather because he failed to “fulfill his academic obligations, including the obligation to teach” and because he violated “University policies in relation to travel and use of University resources.”
Salby and his supporters find it hard to believe the school’s claims. Salby’s detractors point to reports of his investigation by the National Science Foundation (NSF) for alleged ethical improprieties, claims surrounding which surfaced on an anti-climate-skeptic blog, along with court papers relating to his divorce. Salby has indeed been embroiled in conflicts with the NSF—the organization debarred him from receiving research grants for three years, even though, teaching in Australia, he wasn’t eligible, anyway—and with the University of Colorado, where he taught previously and was involved in a decade-long dispute with another academic. At one point, the NSF investigated the disappearance of $100,000 in Salby’s research funds, which, in the wake of the investigation, was returned to Salby’s group. However, all these matters have involved bureaucratic rights and wrongs. They have no bearing on his science, just as Antoine Lavoisier’s being a tax farmer had no bearing on his demolition of the phlogiston theory of combustion. And Salby had earned high marks as a scientist. He originally trained as an aerospace engineer before switching to atmospheric physics and building a distinguished career. He taught at Georgia Tech, Princeton, Hebrew, and Stockholm Universities before coming to the University of Colorado, and he was involved as a reviewer in the IPCC’s first two assessment reports.
Starting in the late 1990s, Salby began a project to analyze changes in atmospheric ozone. His research found evidence of systematic recovery in ozone, validating the science behind the 1987 Montreal Protocol, which introduced specific steps for curtailing ozone-depleting gases. Preparing to write a graduate-level textbook, Physics of the Atmosphere and Climate, later published by Cambridge University Press and praised by one reviewer as “unequalled in breadth, depth and lucidity,” Salby then undertook a methodical examination of AGW. What he found left him “absolutely surprised.”
Most discussion on the science of AGW revolves around the climatic effects of increased levels of carbon dioxide in the atmosphere. How it got there in the first place—the assumption being that increased carbon dioxide arises overwhelmingly from human activities—is often taken for granted. Yet Salby believed that he had uncovered clear evidence that this was not the case, as his trip to Europe was designed to expose.
The IPCC estimates that, since the Industrial Revolution, humans have released 365 billion tons of carbon from burning fossil fuels. Annual emissions, including those from deforestation and cement production, are less than 9 billion tons. Yet natural carbon cycles involve annual exchanges of carbon between the atmosphere, the land, and the oceans many times greater than emissions from human activities. The IPCC estimates that 118.7 billion tons of carbon per year is emitted from land and 78.4 billion tons from oceans. Thus, the human contribution of 9 billion tons annually accounts for less than 5 percent of the total gross emissions. The AGW hypothesis, as well as all the climate-change policies that depend on it, assumes that the human 5 percent drives the overall change in the amount of CO2 in the atmosphere—and that the other 95 percent, comprising natural emissions, is counterbalanced by absorption of CO2 from the atmosphere by natural processes. Summing it up, the IPCC declared in its fourth assessment report, in 2007: “The increase in atmospheric CO2 is known to be caused by human activities.”
Salby contends that the IPCC’s claim isn’t supported by observations. Scientists’ understanding of the complex climate dynamics is undeveloped, not least because the ocean’s heat capacity is a thousand times greater than that of the atmosphere and relevant physical observations of the oceans are so sparse. Until this is remedied, the science cannot be settled. In Salby’s view, the evidence actually suggests that the causality underlying AGW should be reversed. Rather than increased levels of CO2 in the atmosphere triggering global temperatures to rise, rising global temperatures come first—and account for the great majority of changes in net emissions of CO2, with changes in soil-moisture conditions explaining most of the rest. Furthermore, these two factors also explain changes in net methane emission, the second-most important “human” greenhouse gas. As for what causes global temperatures to rise, Salby says that one of the most important factors influencing temperature is heat exchange between the atmosphere and the ocean.
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