(note: I am not an actual climate scientist/atmospheric modeler, but I do work in the climate field and have done so for a long time)

The IPCC's RCP8.5 "worst-case credible scenario" - the one with collapse as its most likely social outcome - has been controversial for quite a while now. As Genevieve Gunther has written, the original attacks on the scenario were from the Right. But mainstream "climate personalities" such as Michael Mann and Zeke Hausfether took up the baton, launching attacks on the scenario as being "alarmist".

In 2025, the Trump administration in its "Gold-Standard Science" executive order took aim by name at RCP8.5, forbidding its use in the US Federal government. This weekend, Trump again took aim at it on Truth Social, interestingly enough, at the exact same time Mann and his allies were doing the same, claiming a victory against alarmism. In the extremely narrow band of people who have any idea what RCP8.5 means, the kerfluffle is meaningful, and people on the adaptation side are already noting that RCP8.5-level emissions are very different from RCP8.5-level impacts, which have, if anything, become more possible.

But this isn't about the numbers. This is about how eager some are to police the bounds of acceptable discourse and how they make common cause with the worst climate deniers - Mann and Trump are hand-in-hand on this. "Both-sides"-ism and false equivalencies - "being too worried about climate change is JUST LIKE denying it" rarely comes from a place of honesty or goodwill. The mainstream's quest for respectibility and dogged pursuit of being considered reasonable even when the other side keeps pushing the bounds of what is reasonable outside of the galaxy leaves reality itself far behind, and should inspire deep worry about who is deciding which numbers are the right ones we hear about and how they are deciding it.