Global Warming and the Pollsters: Who's Right?

June 16, 2010 — -- Is the glass half empty, or half full?

Public opinion polls on global warming seem to be all over the map these days. A Gallup poll in March indicated that nearly half the people in the United States think the consequences are exaggerated and they're not particularly worried about their future. But two polls released in the last few days show that most Americans believe global warming is real, the consequences could be great, and it's largely our fault.

All three of these polls were conducted by professionals, so why do they seemingly disagree? Mainly, it's in how the questions were asked, and how the data was interpreted. On the surface, it appears that Americans are deeply divided over the issue, wafting back and forth because it was a mild winter, or it's a hot spring, neither of which have anything to do with global climate change.

"Several national surveys released during the last eight months have been interpreted as showing that fewer and fewer Americans believe that climate change is real, human-caused and threatening to people," said Jon Krosnick, a professor of communication and of political science at Stanford University. "But our new survey shows just the opposite," he said in releasing a new national poll conducted by Stanford's Woods Institute for the Environment.

The Stanford poll was conducted June 1-7, and it found that three out of four Americans believe the Earth is warming because of human activity, and they want the government to stop it. But that's down 10 percent from a Stanford poll in 2007, dropping from 84 percent to 74 percent.

Public concern is going down?

Not according to another poll released on June 8, showing that public concern is growing, not dropping. That national poll, conducted by Yale and George Mason Universities from May 14, 2009 to June 1, 2010, found that 61 percent of Americans believe global warming is real (an increase of four points since January) and 50 percent (an increase of three points) believe it is caused mostly by humans.

The numbers don't match precisely, but both polls show that most Americans now believe in the urgency of addressing climate change, even if it means paying a hefty price.

The Yale study took a broader look at public attitudes toward many environmental issues, and the results show that Americans care deeply about what we are doing to the Earth. Some 77 percent, for example, "support regulating carbon dioxide as a pollutant," up 6 percent, and of course that's the dominant greenhouse gas, so this appears to be strong support for dealing with global warming.

In that same poll, 87 percent support funding more research into renewable energy sources, and 65 percent support signing an international treaty that requires the United States to cut its emissions of carbon dioxide 90 percent by 2050. Again, those are global warming issues.

So Americans feel deeply about the environment, and the control of human activities that contribute to global warming, so what's with that Gallup poll suggesting that we don't give a rip?

According to Stanford's Krosnick, the Gallup poll underestimated public concern because it focused on a public opinion question developed by George Gallup in the 1930s. It's known among pollsters as the "most important problem."

How would you answer this question?

"What do you think is the most important problem facing the country today?"

Global warming? Not likely, even if you believe it's real. Like most Americans, you would probably place it at or near the end of a list of 20 problems, far below immediate issues like the economy, terrorism, and national security. However, many news reports emphasized the bottom ranking of global warming, suggesting Americans are unimpressed. The Pew Research Center came out with a similar finding in January.

Like the other polls, the Gallup survey found that most Americans (53 percent) believe it's real. But skepticism over the gravity of the consequences has risen sharply since the same questions were first asked in the annual poll conducted by Gallup in 1997. During that 13 year period the percentage of respondents who believe the effects have been exaggerated climbed from 31 percent to 48 percent.

And scientists, according to the participants in the Gallup poll, aren't too sure themselves.

But that's contrary to one major study at the University of Illinois at Chicago. That study surveyed 3,146 earth scientists around the world and found overwhelming agreement that the world has been warming over the past 200 years (90 percent) and human activities are a significant factor (82 percent.) Significantly, this survey involved scientists who are closest to the issue. Climate scientists were almost universal (97 percent) in their belief that humans are largely to blame. Meteorologists, who deal primarily with near-term weather conditions, were less convinced (64 percent.) Climate scientists focus on long-term changes, like global climate change, leading Peter Doran, associate professor of earth and environmental sciences at Illinois, to conclude:

"The take-home message is, the more you know about the field of climate science, the more you're likely to believe in global warming and humankind's contribution to it."

Although the polls do not all agree on the numbers, or even the trends, the underlying message is that most people are now recognizing that global warming is real, the consequences are significant, but at the moment they don't rank up there with getting a job and protecting the country from terrorists.

But there is one fundamental problem that all pollsters face when quizzing the public about such things as global climate and the environment. We tend to take a short-term view.

At this very moment the nation is confronting one of the most devastating human-induced environmental disasters in its history. Could any environmental poll conducted while oil is washing up on beaches along the entire Gulf coast not be affected by the dreadful images that we see, day after day after day?

Public opinion changes, sometimes on whims, sometimes on disasters. But if there's one thing all of these polls show, it's that people are paying attention now, more so than ever before. There may be some confusion, and the consequences may seem distant and imprecise, but most Americans are now coming to grips with global warming and what we need to do to stop it.