The theory that the earth is catastrophically heating up because of industrial pollution has become one of the leading environmental topics on network television news. Global warming is a highly controversial issue, with most climate scientists unconvinced that human actions are warming the planet, or that such warming would even be harmful. Such views, however, do not make it into newscasts. Instead, as with so many other issues, global warming is usually portrayed in a science-and-activists- versus-industry paradigm.

Media Research Center analysts reviewed all of the stories about global warming on ABC’s World News Tonight, CBS Evening News, CNN World News and The World Today, and NBC Nightly News from January, 1993 through October, 1997. There were a total of 48 stories.

Story Heats Up. The 48 stories were not evenly distributed throughout the years. Global warming has become a bigger story lately, with more stories so far in 1997 (26) than in all of the other years combined (22). The heavy coverage so far in 1997 has been a result of White House public relations activities, such as the inviting of the nation’s local television weathermen for a presidential briefing. In 1993 and 1994, when the Democrats controlled both houses of Congress and the White House, but didn’t push for action on global warming, the networks were largely silent.

No Room for Scientific Debate. Most of the stories (39) simply assumed that science supports warming theories. Only seven stories included a mention that many scientists are skeptical of global warming. Of these seven stories, only two brought up the actual arguments of skeptical climate scientists. (The remaining two stories were about scientific efforts to measure the earth’s warming; they neither assumed science supports warming theories, nor mentioned arguments against such theories.)

Peter Jennings has been the most adamant in claiming that the scientific debate is over. On the April 5, 1995 World News Tonight, Jennings argued that "it would only take a small increase in the world’s overall temperature to change life as we know it" and that there was "new evidence that man may be turning up the thermostat."

On the November 30, 1995 broadcast, Jennings announced, "2,500 scientists from around the world have finally agreed with one another and are convinced that burning oil and coal is causing the world’s temperatures to rise, which may bring with it environmental disaster."

On the October 1, 1997 broadcast, he claimed that pollution "has already changed the world’s climate" and that "if man doesn’t stop tampering with the environment, the change in climate could well lead to a world in which we have a very unpredictable future."

And then on October 22, 1997, Jennings told World News Tonight viewers that "the overwhelming majority of scientists now agree [climate change] is being caused by man."

Others were a bit more balanced. "The earth does seem to be heating," reported NBC’s Robert Hager on the April 7, 1997 Nightly News, "some think because of pollution, others say it’s just cyclical." And although CNN’s Cammy McCormick, on the October 6, 1997 World Today, said that "most [scientists] will tell you that the earth is heating up and people are partly to blame," she pointed out that "some climate scientists say they’re not convinced about global warming."

No report mentioned that nearly 100 climate scientists signed the Leipzig Declaration in 1996, expressing doubts about the validity of computer-driven global warming forecasts.

And about those 2,500 scientists Jennings mentioned, S. Fred Singer, professor of environmental sciences at the University of Virginia, wrote in the July 25 Wall Street Journal: "The great majority of these are not conversant with the intricacies of atmospheric physics, although some may know a lot about forestry, fisheries or agriculture. Most are social scientists — or just policy experts and government functionaries. Every country seems to be represented — from Albania to Zimbabwe — though many are not exactly at the forefront of research. The list even includes known skeptics of global warming — much to their personal and professional chagrin."

According to Dr. Singer, "Even some IPCC scientists, in the report itself or in a May 16 Science article headlined ‘Greenhouse Forecasting Still Cloudy,’ have expressed doubts about the validity of computer models and about the main IPCC conclusion, that ‘the balance of evidence suggests a discernible human influence on global climate’ — whatever that ambiguous phrase may mean."

He also pointed out that most of the warming over the past hundred years occurred before 1940, even though there were more carbon dioxide emissions after the second World War, and that "weather satellite observations, independently backed by data from balloon-borne source sensors, have shown no global warming whatsoever in the past 20 years."

Dr. Singer isn’t alone. A Gallup Poll found that only 17 percent of the members of the Meteorology Society and the American Geophysical Society think that the warming of the 20th century has been a result of greenhouse gas emissions.

Disaster Awaits. Not only did the networks report unquestioningly that humans were warming the planet, but they were certain that such warming would lead to disaster. Only two of the 48 global warming stories pointed out that some scientists believe warming would be a boon to human health and well-being. The other stories assumed warming was bad.

On the October 7, 1997 Nightly News, NBC correspondent George Lewis predicted that warming would lead to "wild swings in the weather, from heavy rains to prolonged droughts, ruining crops all over earth." He also ran a computer animation from an environmental group which "shows how a three foot rise [in sea levels] would flood New York City, cause some of the Florida Keys to disappear, and expand San Francisco Bay all the way into California’s Central Valley." CBS correspondent Scott Pelley, on the October 22, 1997 CBS Evening News, said, "Scientists are already measuring the destruction, from floods in American valleys to vanishing ice on world peaks...In fact, it is happening all around the world — the earth’s glaciers have been receding at an increasing pace over the last 100 years."

Dr. Singer, again, dispels these claims. "Judging from the climate record of the last 3,000 years of human history, climate consequences of a greenhouse warming should be generally beneficial," he wrote in a recent Science & Environmental Policy Project report. "One would expect severe weather to be less frequent because of (calculated) reduced equator-to-pole temperature gradients. In fact, the frequency and intensity of hurricanes have decreased over the past 50 years, although the reason for this is not known."

Expert Soundbite Sources. The skewed nature of the global warming debate in the media can be seen by whom network reporters interviewed for soundbites. In the 48 stories during the study period, there were 60 soundbites from those who thought global warming was a problem and favored drastic policy solutions.

Only 10 soundbites came from the other side, with only two of those coming from scientists. (Fifteen soundbites came from neutral sources.) Reporters often used soundbites to frame the debate as being between science and environmental activists on one side and industry on the other. On the October 22, 1997 NBC Nightly News, for instance, correspondent David Bloom, pitted the Sierra Club’s Dan Becker against a representative of the coal industry, who claimed the plan would cost jobs. Scientists skeptical of warming were ignored.

NBC News, though, did go the farthest of all the networks toward balance. Twice the Nightly News used its "In Their Own Words" segment to allow critics of global warming policies to speak. On the July 8, 1996 broadcast, Singer made the case against human- induced global warming and on October 7, 1997 Thomas Moore of the Hoover Institution argued that global warming would promote human health.

But these were the exceptions. For the most part, the debate in the media over global warming has been one-sided, with the legions of scientists skeptical of global warming completely left out.

This Issue Analysis is adapted from a Free Market Project Special Report on network coverage of the global warming debate. To see the full report, visit the MRC’s web site at www.mediaresearch.org or call (703) 683-9733.

— Rich Noyes