In addition to my career as a PhD chemist, I am one of a select few who enjoy the privilege of moderating content on reddit.com’s science forum. The science forum is a small part of reddit, but it nonetheless enjoys over 4 million subscribers. By comparison, that’s roughly twice the circulation of The New York Times.

The forum, known as /r/science, provides a digital space for discussions about recent, peer-reviewed scientific publications. This puts us (along with /r/AskScience) on the front line of the science-public interface. On our little page, scientists and nonscientists can connect through discussions on everything from subatomic particles to interstellar astrophysics.

As a moderator of this discussion, I’ve observed scientific discourse across a wide variety of disciplines. I consider it a microcosm, representative of the vast range of views that can be supported by empirical evidence. Importantly, it provides the same window for those who are not scientists, who do not regularly talk with PhDs, and who may be unfamiliar with how science is discussed by scientists. In essence, it is a window into the Ivory Tower.

Given that our users are mainly academics (and all are nerds), the discussion generally resembles any scientific debate. That is, there are always numerous links to peer-reviewed science to support positions, people don’t deliberately mislead or misrepresent content, and there is a basic level of respect shared regardless of position. When a user strays from such decorum, they are kindly warned and, if necessary, the comment is removed.

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Some issues, however, are particularly contentious. While evolution and vaccines do have their detractors, no topic consistently evokes such rude, uninformed, and outspoken opinions as climate change.

Instead of the reasoned and civil conversations that arise in most threads, when it came to climate change the comment sections became a battleground. Rather than making thoughtful arguments based on peer-reviewed science to refute man-made climate change, contrarians immediately resorted to aggressive behaviors. On one side, deniers accused any of the hard-working scientists whose research supported and furthered our understanding of man-made climate change of being bought by “Big Green.” On the other side, deniers were frequently insulted and accused of being paid to comment on reddit by “Big Oil.”

After some time interacting with the regular denier posters, it became clear that they could not or would not improve their demeanor. These problematic users were not the common “internet trolls” looking to have a little fun upsetting people. Such users are practically the norm on reddit. These people were true believers, blind to the fact that their arguments were hopelessly flawed, the result of cherry-picked data and conspiratorial thinking. They had no idea that the smart-sounding talking points from their preferred climate blog were, even to a casual climate science observer, plainly wrong. They were completely enamored by the emotionally charged and rhetoric-based arguments of pundits on talk radio and Fox News.

As a scientist myself, it became clear to me that the contrarians were not capable of providing the science to support their “skepticism” on climate change. The evidence simply does not exist to justify continued denial that climate change is caused by humans and will be bad. There is always legitimate debate around the cutting edge of research, something we see regularly. But with climate change, science that has been established, constantly tested, and reaffirmed for decades was routinely called into question.

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Over and over, solid peer-reviewed science was insulted as corrupt, while blog posts from fossil-fuel-funded groups were cited as objective fact. Worst of all, they didn’t even get the irony of quoting oil-funded blogs that called university scientists biased.

The end result was a disservice to science and to rational exploration, not to mention the scholarly audience we are proud to have cultivated. When 97 percent of climate scientists agree that man is changing the climate, we would hope the comments would at least acknowledge if not reflect such widespread consensus. Since that was not the case, we needed more than just an ad hoc approach to correct the situation.

The answer was found in the form of proactive moderation. About a year ago, we moderators became increasingly stringent with deniers. When a potentially controversial submission was posted, a warning would be issued stating the rules for comments (most importantly that your comment isn’t a conspiracy theory) and advising that further violations of the rules could result in the commenter being banned from the forum.

As expected, several users reacted strongly to this. As a site, reddit is passionately dedicated to free speech, so we expected considerable blowback. But the widespread outrage we feared never materialized, and the atmosphere greatly improved.

We discovered that the disruptive faction that bombarded climate change posts was actually substantially smaller than it had seemed. Just a small handful of people ran all of the most offensive accounts. What looked like a substantial group of objective skeptics to the outside observer was actually just a few bitter and biased posters with more opinions then evidence.

Negating the ability of this misguided group to post to the forum quickly resulted in a change in the culture within the comments. Where once there were personal insults and bitter accusations, there is now discussion of the relevant aspects of the research. Instead of (almost comically) paranoid and delusional conspiracy theories, we have knowledgeable users explaining complicated concepts to non-scientists who are simply interested in understanding the research. While we won’t claim /r/science is perfect, users seem happy with the changes made.

Like our commenters, professional climate change deniers have an outsized influence in the media and the public. And like our commenters, their rejection of climate science is not based on an accurate understanding of the science but on political preferences and personality. As moderators responsible for what millions of people see, we felt that to allow a handful of commenters to so purposefully mislead our audience was simply immoral.

So if a half-dozen volunteers can keep a page with more than 4 million users from being a microphone for the antiscientific, is it too much to ask for newspapers to police their own editorial pages as proficiently?