A couple of weeks back Roger Pielke Jr. called sending RCP8.5 to the glue factory “The most significant development in climate research in decades”, a phrase he repeated on his The Honest Broker Substack a week later. And with what might be called touching naivete, on X he described his own Substack piece as “The most important post ever at THB?” Because unfortunately what is important about it, at least so far, isn’t the way in which climate researchers, advocates and journalists (but we repeat ourselves) have come forward to share the news, admit RCP8.5 was a blot on the escutcheon of science as well as agitprop, and swear to be more careful next time. Instead it’s the way they’ve circled the wagons around its bleached bones to insist that it’s a prize animal. As RPJ also noted and we commented on it last week, initial media coverage was distinctly discouraging. And we’re back because they are and it’s just getting worse. At a time when honesty was crucial to restoring their diminished credibility, they chose the wrong course. So we know they’re the kind of people who don’t just make polemical mistakes, they then deny it. Which is as regrettable as it is significant.

Canada’s CBC, for instance, snarled “Trump is wrong. Climate action is working”. Trump? What has he to do with it, even for people who see everything through the lens of politics, spin and maneuvering for tactical advantage rather than boring outdated concepts like truth?

Well, see, the Orange Climate Demon jumped onto his own “Truth Social” network to say the kinds of things he says that generally don’t advance the discussion much, such as “GREEN NEW SCAM” and “Dumocrats”. But instead of rising above his level, they sank beneath it. And in a way that makes you think they’re all following a script not even thinking for themselves. Including quoting Zeke Hausfather, Detlef van Vuuren or both. Are there no other scientists? Especially as van Vuuren is an institutional participant in this debate not a dispassionate observer of it.

An item in The New Republic, for instance, said “Trump Twisted a Climate Debate Beyond Recognition”. There’s that man again. And it took a sneering rather than sober or even repentant tone:

“Researchers concluded that one future climate scenario is unlikely to happen. Right-wingers went wild.”

Went wild, did we? Unlike you with RCP8.5? Which this piece now denies was ever a prediction or presented as likely though in fact it was the go-to “business as usual” climate scenario for the herd of independent minds until very recently. Instead, we’re now told:

“Some 15 additional years of observable data about climate change, real-world climate policy, and the relatively recent, rapid proliferation of cheap renewables have now made the coal-heavy world of RCP8.5 look much less likely than it did in 2013.”

In fact it never looked likely. It was always impossible. And obviously so. And they didn’t check it then and won’t admit it now. Instead, they produce this boilerplate. And this character assassination:

“The reasons why RCP8.5 seems to have struck such a nerve on the right stem from a series of wonky debates among academics that started nearly a decade ago. Two researchers at the University of British Columbia – Justin Ritchie and Hadi Dowlatabadi – published a pair of papers back in 2017 arguing that the modelers relied too heavily on coal, and that extremely high coal usage in RCP8.5 entailed burning through more coal than exists in the world’s recoverable reserves of that resource. Subsequent entries into this debate cautioned against treating RCP8.5 as a ‘business as usual’ outcome when the world looked increasingly on track to warm by roughly three rather than four or five degrees Celsius by 2100. Right-wing think tanks and climate skeptics glommed onto this debate to make a handful of bad-faith arguments that have relatively little to do with the generally good-faith academic discussions about the merits of RCP8.5.”

Good-faith? When you now say you knew in 2017 that it couldn’t happen and that in 2026 you know it could have but won’t? And where are these “academic discussions” and why are we only hearing of them now? What did you know, and when did you know it?

Carbon Brief has the gall to offer a “Factcheck: Trump’s false claims about the IPCC and ‘RCP8.5’ climate scenario”. Trump Trump Trump. Never mind science. Or RCP 8.5 which (all together now) was not a prediction, just a scare story labeled business as usual:

“These scenarios are not predictions or forecasts of what will happen in the future. Therefore, Trump’s declaration that projections under RCP8.5 were ‘wrong, wrong, wrong’ misrepresents the purpose of emissions scenarios.”

As for it being a prediction:

“When it was originally published in 2011, RCP8.5 was intended to reflect the high end – roughly the 90th percentile – of the baseline scenarios available in the scientific literature at the time. A ‘baseline’ scenario is one that assumes no climate mitigation, explains Dr Chris Smith, senior research scholar at the International Institute for Applied Systems Analysis (IIASA) in Austria.”

So it was a business-as-usual prediction? Are you addled? Oh no. And here comes (wait for it) Detlef van Vuuren:

“The scenario assumed a world without climate policy and was designed to explore the consequences of high levels of greenhouse gases and global warming. It was not, van Vueren says, a ‘best-guess scenario’ of what the future held in store. However, in some research papers, RCP8.5 was characterised as ‘business as usual’, suggesting that it was the likely outcome if society did not pursue climate action. This was ‘incorrect’, says van Vuuren, noting that RCP8.5 ‘is not a likely outcome’. He adds: ‘It’s never been a likely outcome.’”

Now you tell us. And then hedge:

“others have argued that while high-emissions scenarios are becoming increasingly unlikely, they still have an important role to play. For example, they highlight risks that only emerge under higher levels of warming. In addition, research has shown that feedbacks in the climate system – where warming triggers the release of more CO2 and methane, which warms the planet further – could mean that human-caused emissions lead to a higher radiative forcing and have a greater climate impact than initially assumed.”

So you get to have your RCP8.5 and eat it too. Including that while it was never plausible, it was but now isn’t:

“In other words, the combination of technological progress and action on climate change that, to date, remains insufficient, means that scenarios of very high or very low emissions are now not considered plausible.”

The Bulletin of the Atomic Scientists was equally useless and in eerily similar terms. Under the all-Trump-all-the-time heading “Sorry, climate change is still dangerous, no matter what nonsense Trump emits” it wrote:

“RCP8.5 was a high-emissions scenario…. When RCP8.5 was first proposed, clean energy was expensive, and coal cheap. But since then clean energy has become very cheap. Between 2009 and 2024, the price of electricity generated by solar power plunged 88 percent, below that of coal and methane gas. So it no longer seems likely that developing nations will meet increasing energy demand with fossil-fuel sources like coal rather than solar, wind, and batteries.”

But renewables are not cheap and there never was that much coal, nor could collapsing economies have sent energy demand surging. Never mind. Couldn’t happen, could have happened, won’t happen, might happen:

“current generations are still at risk of seeing a temperature increase like the one projected under RCP8.5…. although climate models have done a remarkably good job predicting the observed warming when fed the actual history of human carbon emissions, they have likely underestimated the effect global heating is having on critical impacts such as ice sheet collapse, sea level rise, and increasingly devastating and deadly weather extremes. It is becoming clear that climate impacts are emerging on the worse side of the range of possible outcomes. This means that even a world 2.5 degrees Celsius warmer could look much like the 4+ degree Celsius world of RCP8.5.”

So again they get to have it and eat it too. And hurl abuse:

“Future carbon emissions scenarios will be determined by politics. But the warming associated with those emissions is determined by physics. Those who fail to acknowledge the fundamental difference between these two things, are as naïve or as mendacious as Donald Trump.”

Mendacious, you say.

Then there’s an item in The Conversation that said:

“Scientists have scrapped the worst‑case climate scenario – because action is making a difference”.

No it’s not. Emissions continue to rise, but not on the RCP8.5 path because they were never on it and never could have been. The Conversation monologue claimed:

“The climate scientists responsible for laying out the range of possible futures removed the RCP8.5 scenarios for a very good reason. Although often slow and incomplete, our efforts to tackle climate change have made a tangible difference. We have averted the worst climate future once thought possible. The job is far from done. Emissions are at record highs and global warming is speeding up. But the removal of this high-emissions scenario isn’t, as Trump and other climate sceptics have claimed, a sign of failed modelling, or that climate change was a hoax. It’s a sign the expansion of solar, wind, electric vehicles and batteries have slowed emissions growth.”

Again, this claim is false. It is obviously false and they could easily have determined that it is false and not said it. But they chose the opposite course, which calls into question everything else they say.

We do not say it is a lie. But we do say that they have failed historian John Lukacs’ test of scholarly probity, a kind of intellectual crookedness in which sincerity becomes worse than deceit.

In his book At the End of an Age Lukacs recalled that in his youth he had adopted a kind of naïve objectivist epistemology that assumed anyone who refused to accept his view once he had explained it must be a fool or a rogue, and when he realised that well-meaning people with brains can disagree he veered into radical relativism before getting back to the golden mean, concluding that:

“it is possible (and there exist, fortunately, examples of it) for a historian or a scientist or, indeed, for any thinking man to present evidences, from a proper employment of sources, that are contrary to his prejudices, or to his politics, or indeed to the inclinations of his mind. Whenever this happens, it manifests in his decision to present (which usually means: not to exclude) evidences not supporting his ideas or theses. Something – not merely by the external material evidence, but something internal and spiritual – compels him to do so. I prefer not to name this kind of intellectual (and moral) probity ‘objective’ (or even ‘detached’). ‘Objectivity’ is a method: I prefer the word honesty, which is something else (and more) than a method: within it there resides at least a modicum of humility (and in history, being the knowledge that human beings have of other human beings, even a spark of understanding, of a human empathy).”

Wise words indeed, and ones that we must remember are not only a useful caution to other people, especially ones we disagree with. But having made that feeble effort at a modicum of humility, we insist that those unwilling to admit that RCP8.5 was never plausible, and using it as a cudgel or a basis for scientific conclusions, or both, was never honest.

To keep doing it is disgraceful.