One of the familiar refrains from the right on global warming goes something like this: “In the 1970s, those stupid scientists actually said the earth was cooling. Now suddenly they’re saying the earth is warning. Ha ha! Those damn liberal pointy headed intellectuals (insert words like “socialist” and “communist” here) don’t have any idea what they’re talking about. Only Real Americans like Joe the Plumber who have never read a single scientific study on the subject know the Real Truth.”
A new survey of the literature in the Bulletin of the American Meteorological Society by Thomas Peterson, William Connolley, and John Fleck pretty much shreds this ridiculous myth, finding that in fact very few climate scientists in the 70s thought there was any cooling on the way (and those that did think that were working with limited data that has been rendered obsolete by new technology). The article begins:
There was no scientific consensus in the 1970s that the Earth was headed into an
imminent ice age. Indeed, the possibility of anthropogenic warming dominated
the peer-reviewed literature even then…
Despite active efforts to answer these questions, the following pervasive myth arose: there was a consensus among climate scientists of the 1970s that either global cooling or a full-fledged ice age was imminent (see the “Perpetuating the myth” sidebar). A review of the climate science literature from 1965 to 1979 shows this myth to be false. The myth’s basis lies in a selective misreading of the texts both by some members of the media at the time and by some
observers today. In fact, emphasis on greenhouse warming dominated the scientific literature even then. The research enterprise that grew in response to the questions articulated by Bryson and others, while considering the forces responsible for cooling, quickly converged on the view that greenhouse warming was likely to dominate on time scales that would be significant to human societies (Charney et al. 1979).
The survey found that there were a total of 7 articles in the scientific literature from 1965 to 1979 that advocated the notion of global cooling. By contrast, there were 44 that advocated global warming. The article concludes with what the National Research Council found in reviewing the literature in 1979:
In July 1979 in Woods Hole, Massachusetts, Jule Charney, one of the pioneers of climate modeling, brought together a panel of experts under the U.S. National Research Council to sort out the state of the science. The panel’s work has become iconic as a foundation for the enterprise of climate change study that followed (Somerville et al. 2007). Such reports are a traditional approach within the United States for eliciting expert views on scientific questions of political and public policy importance (Weart 2003).
In this case, the panel concluded that the potential damage from greenhouse gases was real and should not be ignored. The potential for cooling, the threat of aerosols, or the possibility of an ice age shows up nowhere in the report. Warming from doubled CO2 of 1.5-4.5 degrees C was possible, the panel reported. While there were huge uncertainties, Verner Suomi, chairman of the National Research Council’s Climate Research Board, wrote in the report’s foreword that he believed there was enough evidence to support action: “A wait-and-see policy may mean waiting until it is too late” (Charney et al. 1979). Clearly, if a national report in the 1970s advocates urgent action to address global warming, then the scientific consensus of the 1970s was not global cooling.
This all reminds me very much of the creationist moon dust myth. They cherry pick a few results from scientists using very primitive measurement techniques and broadcast them with a megaphone, ignoring the reams of data that we have now from much more accurate ways of measuring global temperatures. In fact, it was the same thing that made that limited data outdated: satellite technology.