Climate scientists have 95% confidence that humans are the main cause of global warming over the past six decades. Their best estimate attributes 100% of global warming since 1950 to human activities. 90 to 100% of climate scientists and their research agree on this. Human-caused global warming is as settled as science gets.

Yet most Americans don’t realize it. Moreover, the more conservative a person’s ideology, the less likely they are to accept this scientific reality or to trust the scientific experts.

According to a new Pew Research Center poll, just 48% of Americans realize that the Earth is warming mostly due to human activity. Highlighting a vast partisan reality gap, 79% of liberal Democrats and just 15% of conservative Republicans answer the question correctly.

Science knowledge matters for Democrats, but not Republicans

Among social scientists, there’s an ongoing debate about whether facts can change peoples’ minds on scientific issues that have become politically polarized, like climate change. There’s some evidence that when conservatives have more scientific knowledge, it just gives them more tools to use in rejecting the scientific information that conflicts with their ideological beliefs.

Pew asked a variety of general science questions to test the correlation between scientific knowledge and acceptance of human-caused global warming. Overall, Democrats and Republicans got the same average score on these scientific questions, although liberal Democrats and conservative Republicans scored better than moderates in both parties. When it came to understanding that humans are causing global warming, Pew found that scientific knowledge makes a huge difference among Democrats, and no difference among Republicans.

Acceptance of human-caused global warming broken down by political affiliation and general science knowledge. Illustration: Pew Research Center

However, previous research has shown that conservatives with climate-specific knowledge are more likely to accept climate realities.

For Democrats, ideology isn’t a factor because the main solutions to the problem (e.g. regulations and pollution taxes) don’t conflict with their ideological beliefs. Thus scientific knowledge determines whether they understand that humans are causing global warming. For three-quarters of American conservatives, their ideology prevents them from accepting that reality, regardless of their scientific literacy.

Republicans distrust climate science experts

The expert consensus on human-caused global warming poses a conundrum for conservatives. People usually defer to the experts, in particular on complex issues like climate science. How can they square an ideological opposition to climate change solutions with the 97% consensus among scientific experts that humans are causing global warming? The Pew survey suggests that conservatives accomplish this by denying the expert consensus, and by distrusting the experts.

The poll asked whether respondents thought that “almost all climate scientists agree that human behavior is mostly responsible for climate change.” Only 27% of Americans were aware of this fact, including just 55% of liberal democrats, 29% of moderate Democrats, and 15% of Republicans.



When asked if climate scientists can be trusted to give full and accurate information on the causes of climate change, only 39% of Americans answered yes, including 70% of liberal Democrats and 15% of conservative Republicans. More than half of conservative Republicans also said that climate scientists’ research findings are influenced by the desire to advance their careers and their political leanings.

In short, when experts tell you something you don’t want to believe, reject their conclusions by accusing them of bias, as we saw conservative Australian senator Malcolm Roberts do recently on Q & A:

Prof Brian Cox and Australian Senator Malcolm Roberts talk climate on Q & A.

Conservative media and politicians created an echo chamber of denial

Research has shown that American conservative media outlets like the Wall Street Journal and Fox News are terribly inaccurate and biased in their climate change reporting. In fact, a study in 2013 found that conservative media consumption decreases viewer trust in scientists and belief that global warming is happening. The Pew survey results further reinforce that finding.

Moreover, a study published last year found that the Republican Party is the only major political party in the world that rejects the need to tackle climate change. This is likely due to the party’s reliance on fossil fuel industry campaign donations.

Humans are causing global warming. Scientific experts agree about this. Smoking causes lung cancer. Gravity is real. Humans landed on the moon. These are all statements that reflect the reality we all live in whether we’re politically liberal or conservative. Political ideology should not determine whether we accept these realities.

And yet in America, on climate change, it does. The Republican Party has created an echo chamber in which their media and political leaders live by the phrase jokingly uttered by Mythbuster Adam Savage:

Republican voters take their cues from party leaders and often get their information from conservative media outlets. On climate change, those leaders and media sources reject reality and substitute their own denial and misinformation, because it benefits them. Their voters become misinformed as a result, and thus don’t demand change from party leaders. Everybody outside the denial echo chamber is puzzled by it, and since it’s impervious to external facts, few know how to break through.

Piercing the echo chamber

Climate scientist Katharine Hayhoe has been trying to make a difference by identifying commonalities with many conservatives, like her evangelical faith.

There are glimmers of hope in the Pew survey. For example, there’s bipartisan support for wind and solar energy, with 83% and 89% of Americans in favor, respectively. As Hayhoe noted in her climate event with President Obama and Leonardo DiCaprio this week, Texas produces the most wind power of any state, generating 10% of its electricity from wind. Because they’re becoming increasingly cheap and popular, clean technologies are giving us a shot at preventing the worst consequences of climate change.

Much like climate change, science denial poses a long-term threat to the Republican Party. And similar to alcoholism, denying the problem doesn’t make it go away; if you don’t accept the problem and take steps to deal with it, reality will eventually come crashing in with disastrous consequences.



There are conservative thought leaders who realize this and are in a battle with the science-denying wing over the future of the Republican Party. With reality on their side, they will eventually win; hopefully before too much irreversible damage is done to the party and to the Earth’s climate.