Should we have acted thirty years ago to prevent global climate change?

• Author: Holcombe, Randall G.
• Position: REFLECTIONS - Viewpoint essay

Global climate change is a major public-policy issue in the first decade of the twenty-first century. Although debate continues about the extent to which the global climate will change, sufficient agreement exists among policymakers worldwide that the governments of 140 nations signed the Kyoto Treaty to limit greenhouse gasses into the atmosphere. The treaty took effect among the 140 ratifying nations on February 16, 2005, the signatories committing themselves to meeting targets limiting the emissions of greenhouse gasses by 2012. (1) Although the evidence on global climate change remains subject to debate, a frequently used argument in favor of acting now is that any delays will make it more costly and more difficult to prevent (or to reduce the effects of) global climate change. If we wait until we are absolutely certain, it may be too late to mitigate the harm, so we should act now on the basis of the best evidence on hand.

However powerful that argument may be, it is hardly a new one. Scientists have been concerned about global climate change for decades, and the popular press has been reporting on the problem for half a century. The argument that we should act now to mitigate the effects of global climate change, on the basis of the best information science has to offer, also goes back decades, yet only recently have public policymakers taken any serious action on this issue. (2) As this article's title suggests, I examine here whether we should have heeded scientists' warnings decades ago and acted in the 1970s (or sooner) to prevent global climate change.

By the 1970s, substantial scientific agreement on global climate change had been reached, and the issue was reported in the popular press, along with policy measures that scientists suggested might be taken to mitigate the otherwise impending change. However, none of the concrete policy actions they suggested at that time was taken. It is worth considering the effects of policy inaction in the face of the scientific consensus that existed on global climate change decades ago.

What Did We Know about Global Climate Change?

Scientists have known for a long time that the earth has passed through periodic cycles of warming and cooling and that during the most recent ice age, glaciers extended well into what is now the territory of the United States, Great Britain, and much of Europe. The cause of these cycles was a matter of speculation, but a pair of articles by Maurice Ewing, director of Columbia University's Lamont Geological Observatory, and geologist-meteorologist William Donn published in Science in 1956 and 1958 attracted attention, partly by offering an explanation of self-perpetuating warming and cooling cycles and partly by arguing that another ice age would begin soon. As Weart (2005) has noted, "Published in 1956, and picked up by journalists who warned that ice sheets might advance within the next few hundred years, the theory gave the public for the first time a respectable scientific backing for images of disastrous climate change." A popular account of Ewing and Donn's ideas appeared in a 1958 article by Betty Friedan in Harper's Magazine, titled "The Coming Ice Age." The article was advertised on the magazine's cover with the words, "The Coming Ice Age: When Will the Glaciers Reach America?" Friedan wrote that "another Ice Age ... will not come as a sudden catastrophe, but as the inevitable culmination of a process that has already begun in northern...