"U.S. worry about global warming is heading back up after several years of expanded public skepticism," according (PDF) to a new poll from Gallup. Also heading back up are the rate of understanding that most scientists accept global warming and the rate of accepting that increases in the global temperature over the last century are mostly due to human activity. But those who think that global warming's effects will affect them in their lifetime are still in a minority.
Asked "Just your impression, which of the one following statements do you think is most accurate?" 62% of respondents preferred "most scientists believe that global warming is occurring," 28% preferred "most scientists believe that global warming is NOT occurring," and 6% preferred "most scientists are unsure about whether global warming is occurring or not." Gallup described the 62% figure as representing "a nearly full return to pre-2010 attitudes."
Asked "And from what you have heard or read, do you believe increases in the Earth's temperature over the last century are due more to the effects of pollution from human activities or natural changes in the environment that are not due to human activities?" 57% of respondents chose the human activities response and 39% chose the natural changes response. The 57% figure is up from 50% in 2010, but lower than the all-time high of 61% in 2007.
Asked "Do you think that global warming will pose a serious threat to you or your way of life in your lifetime?" 34% of respondents said yes, 64% of respondents said no, and 1% expressed no opinion. But 54% of respondents to a separate question about when global warming's effects will begin thought that they have already begun to happen, with 3% thinking that they will begin within a few years and 9% thinking that they will begin within their lifetime.
Finally, asked "Which comes closer to your view — it is possible to take specific actions that will slow down the effects of global warming or the effects of global warming are part of a natural process that can't be altered?" 56% of respondents thought that specific actions to slow down the effects are possible, 40% thought not, and 5% expressed no opinion. The new poll was the first in which Gallup asked the question, so no longitudinal comparison is possible.
Asked "Next, thinking about the issue of global warming, how well do you feel you understand this issue?" 27% of respondents preferred "very well," 52% preferred "fairly well," 18% preferred "not very well," and 3% preferred "not at all." The 27% figure is comparable to results from previous polls from 2010 on; Gallup used a different question (including a reference to the greenhouse effect) previously and received a lower rate of "very well" answers.
Overall, Gallup summarizes, "trends throughout the past decade — and some stretching back to 1989 — have shown generally consistent majority support for the idea that global warming is real, that human activities cause it, and that news reports on it are correct, if not underestimated." Despite a fall in support in the last few years, Gallup adds, now "attitudes are returning to previous levels, putting them near the long-term averages."
The poll was conducted by telephone interviews conducted March 7-10, 2013, with a random sample of 1,022 adults, aged 18 and older, living in all 50 U.S. states and the District of Columbia; the sample was weighted to correct for unequal selection probability, nonresponse, and double coverage of landline and cell users in the two sampling frames, and to match national demographics. The maximum margin of sampling error for the total sample was +/4 percent.