WASHINGTON — May 16, 2026 — President Donald J. Trump on Friday took a public victory lap after the international committee responsible for the United Nations’ official climate scenarios formally declared the long-dominant RCP8.5 worst-case projection — and its successors SSP5-8.5 and SSP3-7.0 — to be “implausible.”
Posting on Truth Social, the president wrote: “GOOD RIDDANCE! After 15 years of Dumocrats promising that ‘Climate Change’ is going to destroy the Planet, the United Nations TOP Climate Committee just admitted that its own projections (RCP8.5) were WRONG! WRONG! WRONG!”
Trump added: “For far too long Climate Activism has been used by Dumocrats to scare Americans, push horrible Energy Policies, and fund BILLIONS into their bogus research programs. Unlike the Dumocrats, who use Climate Alarmism nonsense to push their GREEN NEW SCAM, my Administration will always be based on TRUTH, SCIENCE, and FACT!”
What the climate committee actually retired
Representative Concentration Pathway 8.5 — better known as RCP8.5 — has anchored the most catastrophic climate projections since 2011. It assumed a near-tripling of global coal use, no meaningful climate policy worldwide, and population growth far above any plausible trajectory. Despite those assumptions sitting outside any realistic energy mix, RCP8.5 was treated as a “business-as-usual” baseline by national governments, central banks, and headline news coverage for more than a decade.
The committee’s decision to retire RCP8.5 and its closely related successors — formally taken in the run-up to the CMIP7 modeling framework adopted earlier this month — represents the most consequential shift in climate-scenario practice since the IPCC’s Fifth Assessment Report. The acknowledgement that the worst-case input was never plausible vindicates years of warnings by analysts who pointed out that real-world emissions had been tracking nowhere near the scenario’s assumed pathway.
The cost of fifteen years of doomsday framing
Public-policy debates, central-bank stress tests, university curricula, and trillions of dollars in regulatory and corporate disclosure decisions were anchored to a scenario the committee now agrees was never realistic. The Network for Greening the Financial System, which guides more than 140 central banks, calibrated its long-term climate-risk scenarios to RCP8.5. National impact assessments in the United States, United Kingdom, Germany, Canada, Australia, and Japan all rested on the same input.
For independent analysts who long argued that the alarmist baseline was driving distorted policy, the retirement is overdue. Roger Pielke Jr., writing on his Substack and at the American Enterprise Institute, called it “the biggest shift in climate science in decades” and noted that the climate-research community had quietly known for years that the scenario was overheated, while continuing to publish papers that used it as the headline finding.
A clean planet remains the right goal
None of this changes the case for a cleaner planet. Clean water, clean air, clean soil, reduced pollution, ecosystem restoration, and responsible stewardship of natural resources are valuable on their own terms. The argument has never been whether the world should pursue those goals — it should — but whether sweeping economic policy should be built on the assumption of an apocalyptic temperature trajectory that the committee itself now concedes was never plausible.
Earth’s atmosphere has cycled through dramatic changes in composition over geological time scales measured in millions of years. The notion that human emissions over a few decades can be cleanly disentangled from those natural cycles, and projected to apocalyptic certainty, has always rested on modeling assumptions far less robust than the public framing suggested.
What changes next
The CMIP7 framework that replaces RCP8.5 still includes a “high” scenario, but its central case is meaningfully lower than the now-retired one. Regulators and policymakers will face pressure to revisit standards calibrated to the old assumption — particularly those baked into financial-sector stress tests, ESG disclosure rules, and infrastructure planning.
Trump’s administration has signalled that it intends to use the retirement as the basis for a broader rollback of climate-emergency-driven energy policy. Whether the international policy machinery, which has long treated RCP8.5 as the headline number for its scariest forecasts, will be as quick to update its public messaging remains to be seen.
What is no longer in dispute is the underlying admission: the international climate science establishment has, in its own modeling framework, retired the scenario that anchored fifteen years of warnings about civilisational collapse. The next phase of the climate debate will have to operate without it.
The independent evidence the modelers ignored for years
The IPCC’s quiet retirement of RCP8.5 did not come from a single new insight. It came from a decade of independent analyses that the climate-modeling community could only ignore for so long.
Real emissions versus the scenario’s assumption. The International Energy Agency’s Stated Policies (STEPS) outlook now projects global annual energy-related CO2 emissions falling under 30 gigatonnes by 2050 — a trajectory tracking the SSP1-3.4 forcing range, not anywhere near RCP8.5. The European Commission’s Joint Research Centre and the U.S. Energy Information Administration produce reference cases in the same neighbourhood. None of them point to the 5-to-7× coal expansion RCP8.5 required.
The “5x more coal than exists” problem. Justin Ritchie and Hadi Dowlatabadi showed in Environmental Research Letters as far back as 2018 that the emissions pathway to RCP8.5 would require a five-fold increase in global coal use by century’s end — an amount larger than several published estimates of recoverable coal reserves. The scenario assumed, in effect, that humanity would burn coal it does not have, abandon every alternative, and choose to do so against its own economic interest. It was a thought experiment dressed as a forecast.
Hausfather and Peters in Nature. The most-cited critique came in early 2020, when Zeke Hausfather and Glen Peters published “Emissions: the ‘business-as-usual’ story is misleading,” urging the climate community to drop RCP8.5 as a baseline. Their plausible 2005–2050 scenarios projected between 2°C and 3°C of warming by 2100 — uncomfortable, but a far cry from the 4-to-5°C apocalyptic figure the worst-case scenario was generating. The paper was published; the headline framing largely continued to ignore it for another six years.
Satellite versus surface-model divergence. Dr. John Christy and Dr. Roy Spencer of the University of Alabama in Huntsville have maintained the UAH satellite temperature record since 1979 — the only direct, continuous record of bulk-atmosphere temperature. Their analysis comparing the CMIP-suite model ensembles against the satellite observations has consistently shown the models running approximately 2–3× hotter than reality in the troposphere. The mainstream response was to dismiss the satellite data; the data has not budged.
The IPCC’s own baseline error. Pielke, Burgess and Ritchie published in Environmental Research Letters (2021) a direct demonstration that IPCC baseline scenarios had systematically over-projected both CO2 emissions and economic growth assumptions for decades. The institutional process had been treating model inputs as forecasts long after their assumptions had been overtaken by reality.
Population assumptions. SSP3-7.0, the second scenario retired in the same decision, assumed a global population approaching 13 billion by 2100. The United Nations’ own median projection sits at 10.4 billion. The scenario was building a future that demographers — including the UN’s own — had already ruled out.
What this means for everything built on the old number
For 15 years the worst-case scenario was treated by central banks, insurance regulators, university researchers, school curricula, NGOs, corporate-disclosure regimes, and most of the news media as the baseline against which all policy was judged. ESG reporting frameworks, Network for Greening the Financial System stress tests, national climate risk assessments in the United States, Canada, Australia, Germany, the United Kingdom, Japan and the Netherlands — all calibrated to the assumption the IPCC has now retired.
That is the policy edifice the climate-skeptic community has been pointing to for years. Its foundation has now been quietly walked back by the same institution that supplied the foundation in the first place.
The case for clean — without the alarm
Nothing in the RCP8.5 retirement undermines the case for clean water, clean air, clean soil, pollution reduction, ecosystem restoration, or responsible resource use. Those goals stand on their merits — public health, biodiversity, intergenerational fairness, simple aesthetic preference for a world that is not poisoned. They never needed an apocalyptic temperature projection to justify them, and they do not need one now.
What changes is the framing of trade-offs. Policies that destroyed industries, transferred trillions in wealth, foreclosed energy choices for developing economies, and silenced dissenting scientists were justified on the basis of a worst-case scenario the climate-modeling establishment now agrees was never realistic. President Trump’s bluntness aside, the substance of his statement matches the substance of the IPCC decision. For everyone who spent the past fifteen years being told to “trust the science,” the science has just moved.
