Public Opinion

Introduction

Public opinion shows itself through government actions, editorials, letters to the editor, blogs, and other means

only imperfectly, even in democracies. Therefore, scientists study public opinion using polls, lists of carefully designed questions that are posed in a uniform way to a number of people randomly selected. Random selection makes the poll unlikely to show a lopsided picture of public opinion.

Dozens of polls of public opinion on global warming have been made over the last few decades. The U.S. population has been particularly well-polled. The polls show that as media coverage of global warming increased starting from the late 1980s through the late 1990s, U.S. public awareness of phrases like “the greenhouse effect” and “global warming” slowly increased, until by 2006 over 90% said “Yes” when asked if they “heard or read anything” about global warming (Nisbet, 2007).

However, being aware of an issue does not guarantee that a person is well-informed about it, or that he or she considers the issue to be important. A 2006 poll showed that about 46% of Americans believed that global warming is “a critical threat” (Chicago Council on Global Affairs, 2007). Thirty-nine percent thought that global warming is “an important but not critical threat.” (Many polls still use the term “global warming” as it is the most popular term for what scientists prefer to call “global climate change.” “Climate change” is a broader term that takes into account that not all areas of the world will necessarily warm, and other changes besides warming will occur.) International polls show that some countries have higher rates of concern and knowledge of global warming, and some have lower. Understanding the causes of global warming is globally low among non-scientists.

Historical Background and Scientific Foundations

The possibility of anthropogenic (human-caused) global warming has been discussed among scientists since the late nineteenth century. Warming weather was noted in the first half of the twentieth century and discussed in various media such as Time magazine, which noted that professional meteorologists were uncertain about whether the warm trend was likely to last more like 20 years or 20,000. The New York Times speculated in 1952 that by 1982, people might be looking back fondly on the warm winters of the 1950s. There was essentially no public discussion during this period of the possibility that human beings might be the cause of global warming, if any warming was occurring. Other causes, such as volcanoes and variations in the sun's energy output, also seemed plausible—as they continued to do until the 1990s and early 2000s, when numerous scientific studies ruled out these mechanisms as the culprits behind global climate change.

However, the idea that human beings might have disastrous effects on the whole planet was made more plausible by the spread of nuclear weapons after World War II (1939-1945). Tens of thousands of nuclear weapons were manufactured by the United States and Soviet Union during the 1950s and 1960s. American oceanographer Roger Revelle (1909-1991), who in the late 1950s became the first scientist to begin measuring increasing concentrations of carbon dioxide in the atmosphere, testified to Congress in 1957 that rising carbon dioxide levels might turn parts of the United States into deserts, melt the Arctic ice, and turn the Soviet Union into a “great maritime nation” in as little as 50 years. (In 2007, Russia planted a flag on the ocean floor at the North Pole, widely seen as a move to establish its claims to the Arctic ocean as sea-ice receded at a surprisingly fast rate, making it more accessible to exploration for oil.) American physicist Gilbert Plass (1921-2004) predicted in a 1959 article in the popular magazine Scientific American that the average global temperature would rise by 3°F (1.6°C) by 2000 (in fact, it rose about twice that much).

However, coverage of the issue was only occasional and uncertainties abounded. Some commentators argued that a warmer, drier world would be a good thing, or that the world was in fact cooling, not warming. Throughout the 1960s and 1970s, the popular science press mingled forecasts of global warming with forecasts of a new Ice Age, confusing popular opinion but accustoming it to the idea that major changes of some sort, probably unpleasant, might be in the works. Starting in the mid to late 1960s, the environmental movement—broad-based popular concern about the impact of air and water pollution, overpopulation, litter, whaling, resource exhaustion, and other human activities on the world—became a permanent fixture in the United States and eventually global politics. The movement's large Earth Day demonstrations of 1970 are credited by historians with helping trigger President Richard Nixon's (1913-1994) decision to form the Environmental Protection Agency (EPA) and sign the Clean Air Act Extension of 1970.

WORDS TO KNOW

ANTHROPOGENIC: Made by people or resulting from human activities. Usually used in the context of emissions that are produced as a result of human activities.

CHLOROFLUOROCARBONS: Members of the larger group of compounds termed halocarbons. All halocarbons contain carbon and halons (chlorine, fluorine, or bromine). When released into the atmosphere, CFCs and other halocarbons deplete the ozone layer and have high global warming potential.

EARTH DAY: An annual global commemoration (every April 22) of concerns about the environment, first celebrated in 1970.

ICE AGE: Period of glacial advance.

METEOROLOGIST: Scientist who specializes in the study of weather. Meteors (stones falling from space) are not studied by meteorologists: the words share a common origin in the Greek meteoron, meaning “of the atmosphere.”

OZONE LAYER: The layer of ozone that begins approximately 9.3 mi (15 km) above Earth and thins to an almost negligible amount at about 31 mi (50 km) and shields Earth from harmful ultraviolet radiation from the sun. The highest natural concentration of ozone (approximately 10 parts per million by volume) occurs in the stratosphere at approximately 15.5 mi (25 km) above Earth. The stratospheric ozone concentration changes throughout the year as stratospheric circulation changes with the seasons. Natural events such as volcanoes and solar flares can produce changes in ozone concentration, but man-made changes are of the greatest concern.

STRATOSPHERE: The region of Earth's atmosphere ranging between about 9 and 30 mi (15 and 50 km) above Earth's surface.

ULTRAVIOLET RADIATION: The energy range just beyond the violet end of the visible spectrum. Although ultraviolet radiation constitutes only about 5% of the total energy emitted from the sun, it is the major energy source for the stratosphere and mesosphere, playing a dominant role in both energy balance and chemical composition.

In the mid to late 1970s, scientific consensus was reached that certain artificial chemicals, namely chlorofluorocarbons (CFCs), could dangerously damage the ozone layer in the stratosphere (uppermost layer of air) that protects life on the surface from the sun's ultraviolet radiation. Although a connection between ozone and climate was not perceived at the time, the idea that the atmosphere is fragile was reinforced in the public mind by coverage of this matter. Further, it diminished the impression that scientists could not make up their minds about a connection between human emissions and global atmospheric change: the scientific community agreed that CFCs were damaging the ozone dangerously. Sweden banned CFC-powered spray cans in 1978, and a global treaty reducing CFC emissions was finally signed in 1987.

Meanwhile, from the mid 1970s onward, scientific opinion began to swing slowly but steadily in favor of the view that the world was warming, not cooling, and that human activities were the cause. Media voices such as the New York Times and Reader's Digest, after 1977, almost ceased to refer to the possibility of a coming Ice Age and spoke instead of global warming.

Organizations began collecting polling data in 1981, as global warming rose to prominence. By 1986, 39% of Americans said “Yes” when asked if they had “heard or read anything about the greenhouse effect” (Nisbet, 2007). From that time forward, awareness has slowly increased to the present. By 1988, after record-breaking summer heat, the percentage of those who had heard of the greenhouse effect had risen to 58%. During the 1990s the percentage hovered around 80%, and had risen to over 90% by 2006.

Impacts and Issues

Despite spreading recognition of the climate-change issue, understanding of the causes of global warming has remained low. In 1994, 57% of the public thought that it was “definitely true” or “probably true” that “the greenhouse effect is caused by a hole in the earth's atmosphere”; in 2000, the percentage was 54%, not significantly different. (Global warming is caused by greenhouse gases released by burning fossil fuels and other human activities, not by “a hole in the atmosphere.”)

In 2001, only 15% of Americans could correctly identify the burning of fossil fuels as the primary cause of global warming, tied with the citizens of Brazil but significantly less than the people of Mexico, where 26% of respondents could answer correctly. Public opinion was mixed regarding whether a scientific consensus exists on global warming. As of 2007, depending on how the question was worded, the number of Americans who think that scientists have reached agreement that human-released carbon dioxide is the major cause of global warming varies from a third to over 60%. In fact, scientific consensus (with a small minority in disagreement) on the reality of global warming and its primary cause was reached starting in the mid 1990s.

It is possible that the prevalence of false balance in media coverage has made the issue confusing to people. False balance is when a media outlet describes the state of expert knowledge about some technical issue, such as climate change, and gives equal space or emphasis to the views of a small number of dissidents and a far larger professional community. A 2004 study of global-warming coverage from 1998 to 2002 in the New York Times, Washington Post, Los Angeles Times, and Wall Street Journal found that 53% of articles gave equal attention to the scientific majority view that humans contribute to global warming and the alternative view, held by a small minority of climate scientists, that climate change is a natural fluctuation. Over 6% of articles even emphasized the minority view. False balance has decreased in recent years, especially since the appearance of the Intergovern-mental Panel on Climate Change's 2007 summary report, which was widely credited with proving the existence of scientific consensus on climate change.

Regardless of causal understanding, in 2006, global polling showed that large percentages of the populations of many countries consider global warming a serious threat. The highest percentages are in South Korea (96% agreeing that it is either a “critical threat” or “important but not critical” threat), Australia (95%), and Mexico (93%), with the Ukraine lowest in concern at 66%. In the United States, 87% saw the threat of global warming as either critical or important.

See Also Climate Change Skeptics; Environmental Protests; Media Influences: False Balance; Media Influences: Ice Age Predictions.

BIBLIOGRAPHY

Books

Weart, Spencer. The Discovery of Global Warming. Cambridge, MA: Harvard University Press, 2004.

Periodicals

Brechin, Steven R. “Comparative Public Opinion and Knowledge on Global Climatic Change and the Kyoto Protocol: The U.S. Versus the World?” The International Journal of Sociology and Public Policy 23 (2003): 106-135.

Mooney, Chris. “Blinded By Science: How ‘Balanced’ Coverage Lets the Scientific Fringe Hijack Reality.” Columbia Journalism Review (November/ December 2004).

Nisbet, Matthew C., and Teresa Myers. “Twenty Years of Public Opinion about Global Warming.” Public Opinion Quarterly 71 (2007): 444-470.

Web Sites

“Poll Finds Worldwide Agreement that Climate Change Is a Threat.” Chicago Council on Global Affairs and WorldPublicOpinion.org, March 13, 2007. <http://www.worldpublicopinion.org/pipa/articles/home_page/329.php?nid=&id=&pnt=329&lb=hmpg1> (accessed October 10, 2007).

Larry Gilman