The Guardian: Climate-change denialism is not "skepticism," it is "motivated reasoning.
So given the evidence is so strong against them, then why do these beliefs garner such passionate, vocal support? It's tempting to say the problem is a simple misunderstanding, because increasing average global temperature can have paradoxical and counterintuitive repercussions, such as causing extreme cold snaps. The obvious response to this misunderstanding is to elucidate the scientific details more clearly and more often.
The problem is that the well-meaning and considered approach hinges on the presupposition that the intended audience is always rational, willing to base or change its position on the balance of evidence. However, recent investigations suggests this might be a supposition too far. A study in 2011 found that conservative white males in the US were far more likely than other Americans to deny climate change. Another study found denialism in the UK was more common among politically conservative individuals with traditional values. A series of investigations published last year by Prof Stephan Lewandowsky and his colleagues – including one with the fantastic title, Nasa Faked the Moon Landing – Therefore, (Climate) Science Is a Hoax: An Anatomy of the Motivated Rejection of Science – found that while subjects subscribing to conspiracist thought tended to reject all scientific propositions they encountered, those with strong traits of conservatism or pronounced free-market world views only tended to reject scientific findings with regulatory implications.
It should be no surprise that the voters and politicians opposed to climate change tend to be of a conservative bent, keen to support free-market ideology. This is part of a phenomenon known as motivated reasoning, where instead of evidence being evaluated critically, it is deliberately interpreted in such a way as to reaffirm a pre-existing belief, demanding impossibly stringent examination of unwelcome evidence while accepting uncritically even the flimsiest information that suits one's needs.
The great psychologist Leon Festinger observed in 1956 that "a man with a conviction is a hard man to change. Tell him you disagree and he turns away. Show him facts or figures and he questions your sources. Appeal to logic and he fails to see your point." This is the essence of the problem, and sadly, Festinger's words ring true today: the conviction of humans is all too often impervious to the very evidence in front of them.
Motivated reasoning is not solely the preserve of conservatives. While nuclear power has been recognised by the IPCC as important in reducing carbon dioxide emissions, staunch and uninformed opposition to nuclear power arises often from the liberal aisle. In the furore over the Fukushima nuclear disaster (which has claimed no lives and probably never will) many environmentalists lost sight of the fact that it was a natural disaster, very possibly exacerbated by climate change, that cost thousands of lives. Instead, they've rushed to condemn nuclear power plants.