From Watts Up With That?
For nearly two decades, a single climate model scenario haunted virtually every apocalyptic headline you read about our planet’s future. Vanishing coastlines, catastrophic droughts, mass extinctions, cities underwater — almost all of it was built on a scenario called RCP 8.5. And now, in a development that climate scientist Roger Pielke Jr. is calling the “most significant development in climate research in decades,” the international committee responsible for producing the official scenarios that feed into IPCC climate assessments has formally eliminated RCP 8.5 — and its successor SSP5-8.5 — from the new framework, classifying them as implausible.
Let that sink in for a moment. Implausible. That’s a weasel word for Impossible. That’s the word the scientists themselves are now using to describe the scenario that dominated two full IPCC assessment cycles, generated tens of thousands of research papers, and provided the raw material for an estimated hundreds of thousands of media stories that told the public — and their children — that the world as we know it was coming to an end.
It’s a good day for science. It’s a terrible indictment of what was done in science’s name.
What Was RCP 8.5, Anyway?
RCP stands for Representative Concentration Pathway. It was one of a family of scenarios developed to give climate modelers a range of possible futures to work with, from aggressive decarbonization at the low end to a worst-case ‘burn everything’ trajectory at the high end. That high end was RCP 8.5 — a scenario requiring atmospheric CO₂ concentrations exceeding 1,000 parts per million by 2100, roughly two and a half times today’s levels. A helpful technical overview of how the scenario was constructed can be found at Carbon Brief, who by the way, swallowed that forecast hook, line, and sinker.
To get there, RCP 8.5 assumed a world that would massively and continuously expand coal consumption for the rest of the century, with coal use eventually exceeding the planet’s estimated recoverable reserves. It assumed population growth far above any credible demographic projection, minimal technological progress, and essentially no energy transition whatsoever. It described a world that, even at its creation, existed more in the realm of dystopian fiction than serious energy analysis.
Researchers knew this early on. As far back as 2017, serious academic work was questioning the scenario’s foundations. By 2020, climate scientists Zeke Hausfather and Glen Peters published a widely-read commentary warning that RCP 8.5 was ‘misleading’ as a business-as-usual scenario and that it ‘becomes increasingly implausible with every passing year.’ That paper has been cited over 1,300 times. But the machine kept running anyway.
The Scale of the Damage: By the Numbers
Here is what makes this moment so extraordinary — and so damning. According to data compiled by Roger Pielke Jr. using Google Scholar, between 2018 and 2021 alone, approximately 17,000 academic papers were published using RCP 8.5. Another 16,900 followed in the subsequent three-year period — meaning the usage of the scenario barely slowed even as its flaws became widely known inside the scientific community.
Those academic papers did not stay in journals. Science “journalism” amplified them. Each alarming study generated news articles, television segments, radio reports, social media posts, and classroom curricula. Conservative estimates suggest that the total number of media articles worldwide referencing RCP 8.5 projections — directly or through the studies that used it — runs into the hundreds of thousands, possibly approaching a million pieces of content over the scenario’s two-decade lifespan. Every one of them carried some version of the same message: this is where we are headed.
Pielke Jr. put it plainly: “Tens of thousands of research papers have been — and continue to be — published using these scenarios, a similar number of media headlines have amplified their findings, and governments and international organizations have built these implausible scenarios into policy and regulation. We now know that all of this is built on a foundation of sand.”
A foundation of sand. That is not a skeptic talking. That is one of the most widely cited climate researchers in the world — writing at The American Enterprise Institute — describing what happened on the scientific establishment’s watch.
The policy consequences of that foundation of sand cannot be overstated. RCP 8.5 provided the scientific cover for policies that, by any honest description, amount to government seizure of the energy economy — the kind of top-down control over production, consumption, and individual choice that previous generations would have recognized as socialism by another name. Mandated vehicle eliminations, forced retirement of power plants, prohibitions on gas appliances, trillion-dollar ‘transition’ spending programs — all of it justified, ultimately, by impact studies running a scenario the scientific community has now declared impossible.
A Generation Robbed of Hope
The numbers about research papers and media articles are significant. But the damage I find most troubling — the damage that doesn’t show up in a policy document or a retracted study — is what this scenario did to children.
For the past fifteen to twenty years, millions of schoolchildren around the world have been educated in classrooms where RCP 8.5 was not presented as a worst-case outlier or a modeling exercise. It was presented as the future. Teachers showed its projections. Textbooks cited its outcomes. Documentary films dramatized its consequences. And the children listening absorbed a message that no child should be handed as established fact: the world is ending, and there may be nothing anyone can do.
The psychological evidence for the resulting damage is now substantial. A landmark global survey published in the Lancet Planetary Health in 2021, covering 10,000 young people aged 16 to 25 across ten countries, found that 59% were very or extremely worried about climate change, and more than 45% said their feelings about climate change negatively affected their daily life and functioning. Three-quarters said they believe the future is frightening. More than half reported feeling sad, anxious, angry, powerless, helpless, or guilty about climate change on a regular basis.
A separate Australian survey of children aged 10 to 14 found that 44% worried about the future impact of climate change,and that one in four children worried that the world would end before they got older. One in four. These are elementary-school children carrying an existential fear in their backpacks.
Research in East London found that approximately half of primary school-aged children were worried about global warming. A 2024 CBS News report quoted a psychology professor at Suffolk University who described how children struggling with climate anxiety often perceive that they have no future or that humanity is simply doomed. Young people are increasingly telling researchers that they believe their lives will be worse than their parents’ lives; not because of economic conditions, but because of the planet they believe they’ve inherited.
This is eco-anxiety. It is real, it is measurable, and it has been quietly building in our children for years while adults argued about climate policy. And a very significant portion of it was seeded not by the observed climate record, but by projections derived from a scenario that the scientific establishment has now officially declared to be implausible.
Let that land where it should. Children were frightened, genuinely, measurably, psychologically harmed, by projections that the scientists who built the framework now say described an impossible future. The curriculum didn’t distinguish between a worst-case modeling exercise and a forecast. The media didn’t either. And so a generation of young people grew up believing they had been handed a dying world.
The Broader Public: A Steady Diet of ‘Climate Porn’
The harm to children is acute, but the harm to the general public has been broader and subtler. Pielke Jr. coined the phrase ‘climate porn’ to describe the genre of alarming content that RCP 8.5 reliably generated — headlines about regions becoming uninhabitable, species wiped out by the millions, agricultural systems collapsing, cities swallowed by the sea. These stories were not fabrications. They were based on real published research. But they were research that had loaded an extreme, implausible scenario into a model and reported the output as though it described something likely.
The result was that the public’s mental map of the future became systematically distorted. Survey after survey showed that ordinary citizens consistently overestimated the speed and severity of projected climate impacts. They had been told, repeatedly and authoritatively, that the worst-case scenario was the expected case. Many adjusted their life expectations accordingly — choices about where to live, whether to have children, how to invest, what to teach their own kids — all shaped in part by projections that rested on a foundation of sand.
Meanwhile, as Pielke Jr. has also documented, the actual trends in weather-related economic losses — adjusted for growth in wealth and exposure — have not been spiraling upward the way RCP 8.5-based projections suggested they would. People who learned that were often shocked, because the narrative they’d been fed for twenty years pointed in exactly the opposite direction.
Give Credit Where It’s Due — Then Ask the Hard Questions
Scientists who pushed back on RCP 8.5 deserve real credit. Hausfather, Peters, Pielke Jr., Justin Ritchie, and others challenged the dominant scenario at professional cost. Questioning the worst-case benchmark was not a popular position in climate science circles, and some of these researchers faced significant friction for saying what needed to be said. They were right, and they persevered.
Science is self-correcting. In this case, after nine years of institutional resistance, the correction has arrived. The Coupled Model Intercomparison Project — CMIP — working under the World Climate Research Programme, has published a new generation of scenarios for IPCC AR7. RCP 8.5 and SSP5-8.5 are gone. The new high-end scenario sits roughly 0.9°C cooler by 2100 than its predecessor. The new medium scenario, which most closely represents the actual trajectory of the world under current policies, overlaps with the International Energy Agency’s baseline projection and implies roughly 2.5°C of warming by late century — a meaningful figure that warrants serious attention, but a world away from the five-plus degrees that generated most of the apocalyptic headlines of the past two decades.
But self-correction this slow, this reluctant, and this consequential demands more than a quiet update to a scenario framework. It demands a reckoning.
The institutions that elevated RCP 8.5 to the center of two IPCC assessment cycles need to seriously examine how it got there and why it stayed so long after its flaws were documented. The journals that published thousands of studies using it without requiring disclosure that they were modeling an implausible extreme need to examine their standards. The media outlets that turned those studies into scare headlines without explaining the scenario’s basis need to reckon with their role. And the educators who incorporated RCP 8.5-derived projections into school curricula as though they were forecasts rather than worst-case modeling exercises owe the children in those classrooms something — at minimum, a correction.
What Comes Next
None of this means the climate debate is over, or that warming is not a legitimate subject of concern and policy attention. The new CMIP7 medium scenario still projects meaningful warming under a business-as-usual trajectory. That warrants serious scientific work and honest public discussion.
What is over, or should be, is the practice of generating research and headlines based on the most extreme, least plausible scenario available and presenting it to the public, and to schoolchildren, as the expected future. That practice was misleading when it started. It was known to be misleading by at least 2017. It continued for years afterward. And now the very committee responsible for producing these scenarios has officially confirmed what critics, including me, had been saying all along.
RCP 8.5 has been given its official death certificate. The generation of children who grew up in its shadow, who were told the world was ending before they’d turn thirty, who carry that weight every day — they deserve to know the truth. The scenario that haunted them was always a worst-case fiction. The future they have been handed is not as dark as they were led to believe.
That message is long overdue. Let’s make sure it reaches them.
Anthony Watts is the founder and editor of WattsUpWithThat.com, the world’s most viewed website on climate, and a Senior Fellow for Environment and Climate at The Heartland Institute.
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