Survey results from researchers at Yale and George Mason point to some subtle shifts in public attitudes and offer hints on how nation’s unusual weather events may be influencing public opinions.

A July update to the widely recognized “Global Warming’s Six Americas” study shows public opinion remaining “relatively stable” over the past three months, but with those most inclined to disregard the issue, “the disengaged,” shrinking from 10 to 6 percent of the study group, and with those rather concerned about it, “the cautious,” increasing from 24 to 29 percent.

The survey results also provide some insights into how public attitudes on climate change might apply to the major party presidential candidates. And they include preliminary insights on how the nation’s recent spate of unusual spring and early summer weather events may influence public attitudes on climate change.

The “Six Americas” survey work is done, and regularly updated, by researchers at Yale University’s Project on Climate Change Communication, directed by Yale Forum Publisher Anthony Leiserowitz, and by George Mason University’s Center for Climate Change Communication, directed by Edward Maibach. Since it was first launched, the “Six Americas” studies, and presentations about them, have become staples at many climate change professional meetings.

Maibach’s group noted that for the first time since the fall of 2008, the percentage of “alarmed Americans,” the group most concerned and motivated on the issue, outnumbers by 13 to 10 percent the group “most dismissive” — those least concerned and least motivated.

The findings from the most recent update, as reported by the Yale team:

• The size of the Six Americas has remained relatively stable since May 2011, with two exceptions: the Disengaged are now only 6 percent of the adult population (down from 10% in May 2011); and the Cautious have increased to 29 percent (up from 24% in May 2011).
• 93 percent of the Alarmed, 92 percent of the Concerned, 74 percent of the Cautious, and 73 percent of the Disengaged say that global warming is affecting weather in the United States. Majorities of these groups also say that global warming made several extreme weather and natural disasters in 2011 worse, including the drought in Texas and Oklahoma, floods in the Mississippi River Valley, and record high temperatures across much of the U.S. By contrast, 90 percent of the Dismissive and 66 percent of the Doubtful say that global warming is not affecting the weather in the U.S.
• If 90 percent of climate scientists were to state publicly that global warming is happening, 66 percent of the Concerned, 58 percent of the Alarmed, and 48 percent of the Cautious say that it would increase their level of concern about the issue. Only 18 percent of the Dismissive, however, say their concern would increase, consistent with their distrust of climate scientists.
• 89 percent of the Alarmed, 77 percent of the Concerned, and 64 percent of the Cautious say that if people with their views worked together, they could influence their elected representatives’ decisions on global warming.
• Half or more of the Alarmed (82%) and Concerned (50%) say they are willing to join a campaign to convince elected officials to do “the right thing” on global warming.
• President Obama is more trusted than [Republican presidential candidate] Mitt Romney as a source of information about global warming by a margin of 64 percentage points among the Alarmed; 40 points among the Concerned; 30 points among the Cautious; and 19 points among the Disengaged. The Doubtful trust the two candidates about equally, while the Dismissive trust Romney more than Obama by 33 points.
• Sixty percent of Americans say they would be more likely to vote for a candidate who supports legislation to reduce the federal income tax, while increasing taxes on fossil fuels by an equal amount (a “revenue-neutral tax swap”); only 20 percent say they would be less likely to vote for such a candidate. 82 percent of the Alarmed, 71 percent of the Concerned, 65 percent of the Cautious, and 51 percent of the Disengaged would favor a candidate holding this position. 43 percent of the Doubtful and 23 percent of the Dismissive would favor such a candidate, however, 31 percent of the Doubtful and 30 percent of the Dismissive say it would make no difference in their votes.

The full report that the July results update — “Global Warming’s Six Americas in March 2012 and November 2011” — can be downloaded as a PDF.