UN Climate Panel Drops Its Most Extreme Warming Pathway
The United Nations climate committee has officially retired its worst‑case warming scenario, a decision finalized earlier this month. The discarded pathways are RCP8.5, SSP5‑8.5 and SSP3‑7.0, which together assumed a near‑tripling of global coal consumption, the absence of any meaningful climate policy, and population growth far beyond any realistic demographic outlook.
For fifteen years these projections served as the default “business as usual” baseline in research, finance and policy circles. Because the assumptions were never plausible, the committee concluded that the scenarios were merely stress tests, not realistic forecasts. Their repeated presentation as likely outcomes had driven headlines, guided trillions of dollars in investment, shaped insurance risk models and framed every major climate policy debate.
The retirement marks the most significant change in climate‑scenario practice since the IPCC’s Fifth Assessment Report. The new CMIP7 modelling framework, adopted at the same time, excludes the retired pathways, meaning future projections will start from a baseline that is at least grounded in observable trends.
The committee stresses that this move does not deny that climate change is occurring or that warming will continue; it simply acknowledges that one particular set of projections was overstated and implausible. President Donald Trump responded on his Truth Social account on Friday, calling the move a victory over what he described as “Climate Alarmism nonsense.” He wrote that the projections were “WRONG! WRONG!
WRONG!” and accused Democrats of using them to promote a “GREEN NEW SCAM.” He framed the retirement as a win for “TRUTH, SCIENCE, and FACT.” While the president’s reaction is predictable and he is using the decision to criticize the Green New Deal and broader climate activism, the core fact remains the UN panel’s own admission that its signature worst‑case projection was not credible.
This acknowledgment reshapes the conversation for investors, who must now update risk models; for regulators, whose stress tests based on the old scenarios lose credibility; and for the public, whose most alarming climate headlines of the past decade were built on a foundation that the committee now calls unrealistic. The change does not solve the climate problem, but it corrects a long‑standing framing error. By discarding a scenario that was never going to happen, the discussion can shift toward projections that reflect actual science rather than an extreme, policy‑free outlook that was used as a scare tactic.
The committee’s statement makes clear it is not declaring climate change a hoax or predicting that warming will stop; it is stating that the worst‑case pathway used to alarm audiences was not realistic—a clarification that, according to the panel, has been overdue.
