IPCC-Affiliated Scientists Revise Extreme Warming Scenarios Downward, Citing Renewable Cost Declines and Emission Trends

A paper published in the journal Geoscientific Model Development, written by scientists affiliated with IPCC processes, concluded that the most extreme warming scenarios — projecting temperature rises of 4 to 5 degrees — have become "implausible." The authors stated that the range of projected climate scenarios for the 21st century "will be smaller than assessed before," citing declining renewable energy costs, the spread of climate policy, and observed emission trajectories.

The sole source available for this synthesis is an opinion column published by the Washington Examiner, authored by Peter Murphy, a senior fellow at the Committee for a Constructive Tomorrow (CFACT), an organization that describes itself as supporting free-market and technological solutions to energy challenges. The column interprets the scientific revision as evidence that the broader climate change narrative has been driven by "scare tactics" rather than sound science, and describes the IPCC and affiliated institutions as having lost credibility.

The column does not include direct response from climate scientists who support mainstream warming projections, nor from the authors of the Geoscientific Model Development paper. The paper's finding that extreme scenarios are implausible does not, as stated in the column, necessarily mean that moderate or significant warming projections have been withdrawn; the column does not distinguish between the elimination of high-end outlier scenarios and a wholesale revision of climate science.