Robert O. Mendelsohn 9, the Edwin Weyerhaeuser Davis Professor, Yale School of Forestry and Environmental Studies, Yale University, June 2009, “Climate Change and Economic Growth,” online: http://www.growthcommission.org/storage/cgdev/documents/gcwp060web.pdf
The heart of the debate about climate change comes from numerous warnings from scientists and others that give the impression that human- induced climate change is an immediate threat to society (IPCC 2007a, 2007c; Stern 2006). Millions of people might be vulnerable to health effects (IPCC 2007a), crop production might fall in the low latitudes (IPCC 2007a), water supplies might dwindle (IPCC 2007a), precipitation might fall in arid regions (IPCC 2007a), extreme events will grow exponentially (Stern 2006), and between 20 and 30 percent of species will risk extinction (IPCC 2007a). Even worse, there may be catastrophic events such as the melting of Greenland or Antarctic ice sheets, causing severe sea-level rise, which would inundate hundreds of millions of people (Dasgupta and others 2009). Proponents argue that there is no time to waste. Unless greenhouse gases are cut dramatically today, economic growth and well-being may be at risk (Stern 2006). These statements are largely alarmist and misleading. Although climate change is a serious problem that deserves attention, society’s immediate behavior has anextremely low probabilityof leading to catastrophic conse- quences. The science and economics of climate change are quite clear that emissions over the next few decades will lead to only mild consequences. The severe impacts predicted by alarmists requirea century (or two, accord- ing to Stern 2006) of no mitigation. Many of the predicted impacts assume that there will be no or little adaptation. The net economic impacts from climate change over the next 50 years will be small regardless. Most of the more severe impacts will take more than a century or even a millennium to unfold, and many of these “potential” impacts will never occur because people will adapt. It is not at all apparent that immediate and dramatic policies need to be developed to thwart long-range climate risks. What is needed are long-run balanced responses.