The divisive power of social media is easy to witness firsthand.

Drop into the comments section of nearly any news story and you’ll find yourself face to face with the unvarnished reactions of your fellow citizens. Online comments span an astonishing spectrum of ideologies, rationales, and novel uses of the English language, but how do they square with actual public opinion? Do commenters accurately reflect the views  of the general public?

Consider public comments on news stories about climate change. Largely out of curiosity, I looked at six different articles on six different Facebook pages, and categorized each comment for its stance, tone, and rationale (see sidebar below for details).

We know that climate change is a polarizing topic with strongly-held but widely-varying viewpoints. But what are people talking about online? How do they say it? Is the conversation productive? As with any scientific endeavor, the first step toward understanding something is to observe and measure it.

Facebook comments amplify the dismissive viewpoint

My first task was to measure the number of posts on each side of the issue. How many comments agreed with climate science compared to those that disagree with or dismiss the science?

A stance that agreed with climate science looked like this: We have to take care of the planet, because we need the planet to take care of us. We have recklessly added excess CO2 to the system.

A post that dismissed climate science would be more like: Billionaires are making money by pushing global warming as a legitimate worry. You’re brainwashed.

And then there were comments that lack clarity or context to tell exactly where the writer was coming from, or perhaps they were neutral on the topic: It’s too late to care about the Earth now, the damage has been done.

At the end of 600 posts, here’s how the balance of views shook out.

Digging deeper and sorting the results by sources reveals interesting disparities.

The Fox News Facebook page carried twice as many science-dismissing comments as the other five pages that were analyzed. Agreement with climate science was clearly the minority view among Fox commenters. In contrast, users at the NASA and NOAA pages were more aligned with the scientific understanding of climate change. Opinions at the three “mainstream media” pages (New York Times, CNN, and The Washington Post) were similar to those at NASA and NOAA, with a clear nod in agreement with the consensus science. It’s worth mentioning that virtually all climate scientists agree that humans are altering Earth’s climate. Dissenting views on causes of climate change are common in the public square, but not in the scientific community.

So how do the Facebook comments compare with overall public opinion? The “Six Americas” research done by social science researchers at Yale University and George Mason University provides a backdrop of how Americans feel about climate change. In March 2016, around the same time the Facebook comments were written, the “Six Americas” spectrum of viewpoints of climate change looked like this:

It wasn’t possible to pinpoint individual comments into the six categories, but merging similar groups showed how the Facebook comments aligned with the Six Americas results.

Around half the Facebook comments agreed with what is often characterized as the “consensus” science , which is similar to what we find in the general population. On the other end of the spectrum, the proportion of posts dismissing climate science was exaggerated compared to the U.S. population at large. The Six Americas report found 21 percent of people to be either doubtful or dismissive about global warming. But 30 percent of Facebook comments held this position, making the contrarians seem about one-third more numerous than nationwide public opinion suggests.

The middle ground of people who were uncertain or unengaged was under-represented in the Facebook conversation. This makes sense, because disengaged people are less likely to participate in public dialog. But absent those neutral points of view, the conversation was dominated by those whose positions were less tractable, less open to change. This can make discourse unproductive, as both sides simply talk past each other.

The takeaway is that compared to the general population in the U.S., Facebook comments on climate change appear more polarized and more dismissive of climate science than the population as a whole. An observer relying on the Facebook comments would get an inaccurate representation of how the public generally feels about climate change.

Science dominates the discussion, particularly for those who disagree with it

What about the rationale behind commenters’ comments? Are people concerned about energy policy? Taxes? The science itself? And does the rationale depend on which side is saying it?

Four categories emerged in examining the driving principle behind each comment.

• The science of climate change.
• Policy, energy use, taxation, or other economic arguments.
• The ethical or human responsibility of human-caused climate change: “We have a duty to take care of the planet.”
• Pure emotion: “Climate change makes me sad.”

Not every post had a discernible rationale. Perhaps an entire category might have been designated for comments seemingly intended solely to be insulting or disparaging. Setting that aside, the discussions overwhelmingly revolved around the science of climate change, with policy considerations a distant second … and human or emotional perspectives playing only a minor role.

The rationale differed between those who agree with climate science and those who dismiss it, and this sheds light on how each audience views the issues around climate change. What’s most surprising is that people who dismiss climate change talked about science much more often than they talked about climate policy or solutions. After all, it’s the potential policy responses to climate change that are unattractive for contrarians, according to academic research.* But people who disagreed with climate science spent most of their energy proffering arguments to undermine the science rather than taking a head-on approach to address the issues that actually concern them. Policy topics such as taxes, trade, or jobs were far down the list of rationales used by those dismissive of the science.

I kept a running list of the most common arguments used to attempt to ignore, misinterpret, or discredit climate science. The hands-down winner was the refrain that “the climate has changed before.” A similar slant disregarded the whole issue by arguing that a changing climate does not pose dangers or merit concerns.

The next grouping of dismissive arguments involved claims that the scientific process is flawed or dishonest. Comments along these lines were particularly prevalent on the Fox News page, which is consistent with the conspiratorial thinking some media critics feel is characteristic of Fox News.

Talking about what’s most important

Straightforward explanations can help address misunderstandings about natural vs. human-caused climate forcings. But it’s much harder to convince some people that science is trustworthy. This illustrates the worldview differences that separate those who understand climate change and those who dismiss it. This gulf is unlikely to be bridged by talking about Milankovitch cycles or carbon isotopes. Researchers have found that educators, scientists, and motivated citizens can be most effective by recognizing that dissenting voices are distinguished more by their overall values than by their science literacy.**

It’s time, past time, for the debate to focus on the best policy approaches, rather than attempting to discredit the overwhelming scientific evidence. Let’s stop rehashing the tired anti-science arguments. These have been debunked countless times and they do nothing to engage us in the actual issues of the day. Instead, shift the conversation to what’s actually relevant and far from settled: climate policy and mitigation and adaptation strategies. There is need for vigorous debate around energy policy, subsidies, taxation, and the social cost of carbon. An open exchange of policy ideas will be no less vehement, but much more pertinent.

While social media comments can seem like a quagmire of knee-jerk over-reactions, public opinion is what drives the political process. Even though the balance of opinions is not representative of the overall population, eavesdropping on these conversations shows how people feel and how they express their positions. In this age of worldview bubbles and ideological stalemates, these voices merit attention.

Acknowledgement: This work was done in collaboration with climate denial expert John Cook, PhD, founder of Skeptical Science and now an assistant professor at George Mason University’s Center for Climate Communication. Cook’s work helps people understand and respond to differing viewpoints on climate science, and his input was instrumental in interpreting the Facebook comments in relation to other forms of climate discourse.

Methods

The study looked at user comments on articles about climate science on the Facebook pages of four different media sources and two science agencies.

Media sources from across the political spectrum were analyzed to measure differences between them. The New York Times and Washington Post generally are seen as having progressive editorial voices, Fox News a conservative voice and audience, and CNN closer to the middle according to a Pew analysis.

In addition, two agency pages were examined, NOAA and NASA Climate Change.

The first 100 comments on each article were analyzed.

This sample size was large enough to give a snapshot of the differences between media sources and of the contrasting stances of the commenters. This sample is not large enough to draw broad conclusions or show trends over time.

Each comment was read and scored along the following categories:

Stance:

• Support/agree with climate science
• Dismiss/disagree with climate science
• Neutral or unable to tell the stance

Type of content posted:

• Information
• Link or citation
• Question
• Persuasive argument
• Reaction or commentary
• Attack another commenter
• Support another commenter

Tone:

• Authoritative
• Snarky, sarcastic
• Insulting
• Angry
• Humorous

Rationale:

• Science
• Policy
• Humanity
• Emotion

Scores were tallied for each article and compared among categories.

References

* “Increasing Influence of Party Identification on Perceived Scientific Agreement and Support for Government Action on Climate Change in the United States, 2006–12,” by Aaron M. McCright, Riley E. Dunlap, and Chenyang Xiao; Weather, Climate, and Society, Vol. 6, No. 2, April 2014.

** “Motivated Rejection of Science,” by Stephan Lewandowsky and Klaus Oberauer; Current Directions in Psychological Science, Vol. 25, Issue 4, pp. 217-222 (First published date: August-10-2016).