IPCC declares RCP8.5 climate scenario implausible, undermining decade‑long forecasts

The Intergovernmental Panel on Climate Change (IPCC) has officially stated that the RCP8.5 emissions pathway, used since 2011 to model severe warming scenarios, is “implausible.” The scenario projected a temperature rise of nearly 4 °C by 2100 based on extreme assumptions such as coal use far exceeding recoverable reserves. Critics, including climate analyst Roger Pielke Jr., argued that the pathway described an unrealistic future, yet it continued to inform thousands of research papers, policy discussions and media narratives.

The admission calls into question the validity of numerous climate policies, regulations and public communications that were built on the RCP8.5 premise. It may prompt a reassessment of climate‑related targets and strategies worldwide, while reinforcing skepticism about alarmist projections that have shaped public discourse over the past decade.