Concern Soars About Global Warming as World's Top Environmental Threat

April 20, 2007 — -- After a year of increasing scientific alarms, public concern about global warming has risen dramatically. The number of Americans identifying it as the world's single biggest environmental problem is double what it was a year ago.

Climate change now places far ahead of any other environmental problem in the public's mind; 33 percent now cite it as the world's top environmental issue, a very high level of agreement on an open-ended question. That's soared from 16 percent a year ago.

The related issue of air pollution ranks a distant second, cited by 13 percent, with all other mentions in the single digits.

This ABC News/Washington Post/Stanford University poll also finds a 10-point increase in the belief that global warming is caused mostly by human activity (to 41 percent, up from 31 percent last year); and a significant decline -- the first in a decade -- in the belief that many scientists disagree on whether global warming is happening.

While 56 percent of Americans still think there's substantial scientific disagreement on global warming, that's down from 64 percent last year (and similar levels in the late 1990s.)

It matters: People who think scientists agree on the issue are much more apt to see it as a very serious problem, to call it important personally, to believe it's mainly caused by human activity, to think it can be addressed and to say the government should do more (indeed, much more) about it.

For the first time, a small majority (52 percent) say global warming is important to them personally. While that's not meaningfully different from last year's 49 percent, it's nearly double the level of concern in 1997 -- just 27 percent. And more than six in 10 Americans (62 percent) now feel they know a good deal about global warming -- again similar to last year, but well up from its level a decade ago.

A variety of other measures of awareness and concern about global warming have held steady from last year, e.g., 84 percent believe it's occurring, 86 percent believe it'll be a serious problem if uncorrected, 63 percent think it indeed can be reduced and 70 percent say the federal government should do more to address it.

This poll supports a series of ABC News reports, "Planet Earth 2007: Seven Ways to Help Save the World," culminating in a "20/20" broadcast hosted by Diane Sawyer that airs Friday, April 20 at 10 p.m. EDT.

The survey finds that nearly all Americans -- 94 percent -- say they're willing to make changes in their lives in order to help the environment generally; 80 percent say so even if it means some personal inconvenience. In one key area, nearly three-quarters (73 percent) say they're already making efforts to reduce energy consumption in their homes.

But the level of commitment is markedly lower. Far fewer, 50 percent, are "very" willing to make changes to benefit the environment; 45 percent are very willing if it means personal inconvenience; and 31 percent are doing "a great deal" to reduce their energy consumption. These are sizable numbers of people, but there's much room for growth.