With a lack of traditional science, partisans on both sides, and enormous consequences depending on popular opinion and political will, it is important that people understand the evidence in the debate over global warming. Unfortunately, most people do not have the time, desire, or ability to undertake an independent study of the issues. Recognizing this, advocates have “packaged” their evidence with charts, graphs, and other visual exhibits designed to have maximum impact with minimal effort on the part of the public. These displays, while appearing to present hard facts, are often misleading.

Environmental activists may be tempted to exaggerate their case in order to convince the public and politicians of the validity of their scenarios. This was illustrated in a statement made by climatologist Stephen H. Schneider, one-time adviser to Vice President Al Gore and author of the book Global Warming: Are We entering the Greenhouse Century? (1989). Schneider said that in order to reduce the risk of potentially disastrous climatic change, “we have to get some broad-based support, to capture the public’s imagination. That, of course, entails getting loads of media coverage. So we have to offer up scary scenarios, make simplified dramatic statements, and make little mention of any doubts we might have.”