Here are a few interesting excerpts from Science & Engineering Indicators 2002, from the National Science Board (released 30 April 2002).  Specifically, these excerpts are from Chapter 7: Science and Technology: Public Attitudes and Public Understanding (PDF, 1,535K).

Data from the 2001 NSF survey show that Americans have been listening to what scientists and others have been saying about global climate change. Nearly 80 percent believe in the existence of global warming, and 53 percent of those surveyed said that the possibility of global warming should be treated as a very serious problem.

Public Attitudes Toward Global Warming

Americans seem to be listening to what scientists and others have been saying about global climate change. Data from the 2001 NSF survey show that 88 percent of the public had heard of global warming, and of those, 77 percent believed that “increased carbon dioxide and other gases released into the atmosphere will, if unchecked, lead to global warming and an increase in average temperatures.

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In addition, in assessing the severity of the problem, an overwhelming majority of those surveyed responded that the possibility of global warming should be treated as either a very serious (53 percent) or somewhat serious (33 percent) problem.

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Gallup polls show an increasing number of Americans “worrying -- about global warming between 1997 and 2000. In 2000, 40 percent of those polled reported that they worried a great deal about the “greenhouse effect, -- or global warming, up from 24 percent in 1997 and 34 percent in 1999. However, the percentage dropped to 33 percent in 2001. The most recent Gallup data show a decrease in the amount of public concern for all 13 environmental problems included in the survey between 2000 and 2001.

Gallup Polls on Environmental Issues

The Gallup Organization has been tracking public attitudes toward environmental issues for more than a decade.

The major findings include the following:

• Americans do not think environmental pollution is one of the most important problems facing the country today. According to a recent Gallup survey, the environment ranked 16th, well below education, the economy, crime, and health care, which top the list of problems identified as the most serious. However, the environment was considered to be the most important problem that will face the United States 25 years from now, more important than Medicare and Social Security and the lack of energy sources, which rank second and third on the list. *
• According to a poll taken in March 2001, 61 percent of respondents believed that global warming is occurring, up from 48 percent who responded the same way in November 1997 (Newport and Saad 2001). The same percentage also believes that human activities are more responsible for increases in the Earth's temperature over the last century than natural causes (one-third of those surveyed said the latter). In addition, 34 percent of those surveyed thought that news reports about the seriousness of global warming are accurate, and another 32 percent thought they were underestimating the problem, leaving only 30 percent who think the press is exaggerating the problem. Although Americans seem to be aware of the issue and believe press reports, they do not appear to be all that concerned. On a list of 13 types of environmental worries, the greenhouse effect, or global warming, ranked 12th.

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*Another survey found scientists to be more concerned than those in other professions about the global environment. That is, they were more likely to agree that “improving the global environment -- should be a top priority (they were also more concerned about population growth) (Pew Research Center for People and the Press 1997).