Climate scientists deem RCP8.5 worst‑case scenario implausible

Researchers, including US climate analyst Zeke Hausfather, argue that the RCP8.5 worst‑case emissions pathway is no longer plausible. They cite dramatic cost reductions in photovoltaics, lithium‑ion batteries and on‑shore wind since 2010, a surge in clean‑energy investment that now exceeds spending on fossil fuels, and the fact that global coal consumption has stabilized and is expected to fall, making the scenario’s high coal‑use assumptions unrealistic.

The scientists warn that discarding RCP8.5 does not eliminate climate risk. Central projections still indicate about 2.7 °C of warming by 2100—well above the 1.5 °C and 2 °C Paris goals—and slow‑acting impacts such as sea‑level rise, ice‑sheet loss and permafrost thaw will continue to develop. In Germany, the shift has sparked a polarized parliamentary debate between alarmist and skeptical voices.