Over the past two weeks, something unprecedented has happened on ScienceAlert's Facebook page. And we need to talk about it.

As members of the Covering Climate Now initiative, we recently strengthened our coverage of climate change. We also proudly supported the Global Climate Strike on 20 September 2019, a day that saw over four million people staging protests around the world, demanding climate action as signs of environmental breakdown rapidly encompass our little blue marble.

It's not strange that a science news publication would talk about climate change and its impact on the world. But the responses that started flooding our Facebook page seemed strange indeed, until we realised what's really going on.

Our readers have expressed surprise at just how many climate change deniers appear to be following us. Lately, every time we post a climate news article on Facebook, with astonishing speed and ferocity the comment section becomes a hot-pot of climate denialism.

Posts will receive hundreds of comments in a short amount of time, often in wild disproportion to the actual reach of the post, or the readership of the article itself. Those metrics are a clear sign the engagement is not organic, but is coming from a targeted source.

As public acceptance of climate science continues to shift towards the scientific consensus, the insidious lobbies who have long-funded climate change denial are mobilising. Their goal is to erode the "consensus gap" between climate scientists and the public. It's nothing new.

But they have started gathering on a new battleground: polluting the comment sections on social media, to make it appear that even readers of science websites like ours don't agree with climate science. Yeah, we're on to them. We're calling them climate trolls.

We don't know where these climate trolls roost. Maybe they come from self-organising grassroots groups with secret Facebook pages. Perhaps the fact they all use the same language and the same memes is indicative of receiving talking points and funding from the fossil fuel industry. Perhaps.

What matters is that ScienceAlert's Facebook page is being targeted, and we are taking action.

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We're a small team of hard-working people. Over the years, our dedication to sharing science news with the world has earned ScienceAlert more than 10 million monthly readers. And with such great reach comes great responsibility.

We will not allow climate trolls to use our reach, visibility, and brand to spread misinformation and lies that go directly against established scientific fact.

Less than a quarter of our monthly readership finds us through Facebook. But we believe our following on that platform is significant enough to warrant a serious intervention on our part.

Unfortunately, the tools Facebook provides for comment moderation are hardly adequate for the job. When a swarm of trolls descends, we can't just turn off the comments. We can't lock individual threads. We have to take out the trash as we see it.

Amidst these targeted attacks, keeping the comment section respectful can take a significant toll on our resources, not to mention the mental health of our staff.

That's exactly what the trolls want, and that's why we need you, our readers, to help us keep things civil.

How you engage in our comment section on Facebook is crucial. When you see one of our posts about climate news, there will inevitably be climate troll comments underneath it. They will post inflammatory, false statements. Offensive memes. They are trying to upset you.

Do not let them. When you see a climate troll comment, please respond by simply tagging ScienceAlert, so our moderators can deal with it as soon as they're able.

We can't stress that enough: do not engage. Every time you reply to an inflammatory comment, Facebook's algorithm pushes it to the top, where more people inevitably jump into the fray. Next thing we know, several threads are spiralling into a shouting match, all while drowning out the important climate news we are trying to share with the world.

It is vitally important to recognise that these shouting matches are far from harmless. Those people you see spewing nonsense about the 'climate hysteria' are not doing so because they're waiting to be persuaded by scientific facts.

They have come to ScienceAlert's page with one goal only: to sow dissent, pollute the conversation, and make it appear that the science of climate change is to be doubted, that it's all some massive conspiracy of "money-grubbing scientists" (we had a good laugh at that one).

If you deeply care about climate change, you may have a strong urge to counter the trolls. They know this. They are actively using that urge to make their comments more prominent than they deserve to be.

Resist that urge with everything you have. Tag us, and move on. We won't hesitate to ban these people from our comment section.

And, by the way, this is not about simple disagreement.

Of course, deploying heavy-handed moderation tactics on a Facebook page, especially one that belongs to a news organisation, will earn cries about "censorship", limiting "free speech", and banning "disagreement".

But that's not how free speech works here. We are not a government oppressing its citizens, or a corporation protecting its financial interests. ScienceAlert is an independent news website, funded solely by display advertisements.

When we ban you from using our extensive Facebook following to spread nonsense about climate change, we're not limiting your speech. We are simply showing you the door.

There's a certain level of squeamishness in media ethics around the idea that news organisations can exert control over who gets to have a say, especially in their social media comment sections: places generally viewed to be a free-for-all, a playing field of ideas, a place for spirited discussion. Nobody wants to be accused of censorship, that antithesis of the free press.

You know who's using that squeamishness? Climate trolls. They know their strength is not in their arguments, but in numbers. As soon as one mole has been whacked down, another pops up; sometimes it's the same person using a second account, coming just to complain about being banned for "disagreeing with ScienceAlert".

Our Facebook comment terms of use have been clear for years. We have no obligation to tolerate this behaviour.

In fact, we want to urge other media outlets to not tolerate it, either. Over the past weeks, all over Facebook, the comment sections on climate news articles have become ideological battlegrounds designed to waste the valuable time that could be spent on meaningful action instead.

If anything, the media has a duty to keep the conversation focussed on the facts. And that includes our comment sections.