According to an article by Nathaniel Gronewold of E&E Reporter, Nielsen Global Online reports that 69% around the world expressed concern about climate change, up slightly from 2009, but just 48% of the US public joined in that concern. Moreover, a sharp 14 point drop in the percentage of the US public concerned about global warming had taken place since 2007.
Nielsen also finds that concern about global warming is lowest in the US and Canada, much lower than in Europe or China, though erosion of concern in China was also documented.
At 48% there is room to argue that the glass of US public support for addressing climate change is either half-full or half-empty. But there is no doubt that the glass has emptied substantially in the last 4 years.
Reasons abound. The financial crisis of 2008 and the resulting economic distress has pushed many issues aside.
Conservatives have successfully made rejection of climate science a litmus test for good standing in the Republican party. A PPP poll found that just 25% of Republican primary voters accept climate science, with most in Governor Perry's camp of dismissing it or charging it is a fraud.
Of Republican Presidential candidates, only Governor Huntsman has tweeted his acceptance of climate science as well as evolution and said prophetically, "call me crazy." Judging by Huntsman's standing in the polls, Republican primary voters are politely doing just that.
I suspect that the decline in concern about climate since 2007 tracked by Nielsen has been evident in most demographic groups but particularly sharp among conservatives and Republicans.
Climate change in the USA will not be addressed without substantial public support to do so. As the numbers in support of taking action dwindle, the concentration of heat trapping gas in the atmoshpere rises each year and global temperatures rise each decade.