Many climate change scientists do not agree that global warming is happening

Editor — The apocalyptic tone that Smith adopted in relation to the environment bears little relation to reality.1 In his editorial Smith asserts, “virtually all scientists agree that global warming is happening.” Global warming is now joining the list of “what everyone knows.”

Whether most scientists outside climatology believe that global warming is happening is less relevant than whether the climatologists do. A letter signed by over 50 leading members of the American Meteorological Society warned about the policies promoted by environmental pressure groups. “The policy initiatives derive from highly uncertain scientific theories. They are based on the unsupported assumption that catastrophic global warming follows from the burning of fossil fuel and requires immediate action. We do not agree.”2 Those who have signed the letter represent the overwhelming majority of climate change scientists in the United States, of whom there are about 60. McMichael and Haines quote the 1995 report of the Intergovernmental Panel on Climate Change (IPCC), which is widely believed to “prove” that climate change induced by humans has occurred.3 The original draft document did not say this. What happened was that the policymakers’ summary (which became the “take home message” for politicians) altered the conclusions of the scientists. This led Dr Frederick Seitz, former head of the United States National Academy of Sciences, to write, “In more than sixty years as a member of the American scientific community … I have never witnessed a more disturbing corruption of the peer-review process than the events that led to this IPCC report.”4

Policymaking should be guided by proved fact, not speculation. Most members of the Intergovernmental Panel on Climate Change believe that current climate models do not accurately portray the atmosphere-ocean system. Measurements made by means of satellites show no global warming but a cooling of 0.13°C between 1979 and 1994.5 Furthermore, since the theory of global warming assumes maximum warming at the poles, why have average temperatures in the Arctic dropped by 0.88°C over the past 50 years?5


1. Smith R. Climate change: decision time in Kyoto. BMJ. 1997;315:1326. . (22 November.) [PMC free article] [PubMed] [Google Scholar]

2. Michaels P. Conspiracy, consensus or correlation? What scientists think about the ‘popular vision’ of global warming. World Climate Review. 1993;1:11. [Google Scholar]

3. McMichael AJ, Haines A. Global climate change: the potential effects on health. BMJ. 1997;315:805–809. [PMC free article] [PubMed] [Google Scholar]

4. Seitz F. Major deception on global warning. Wall Street Journal 1996 June 12;section A:16(col 3).

5. Balling RC. Global warming: messy models, decent data and pointless policy. In: Bailey R, editor. The true state of the planet. New York: Free Press; 1995. pp. 83–107. [Google Scholar]