Trump Falsely Claims IPCC Scrapped RCP8.5 as Scientists Still Warn of 2.5-3C Warming
Updated
Updated · The New Republic · May 26
Trump Falsely Claims IPCC Scrapped RCP8.5 as Scientists Still Warn of 2.5-3C Warming
4 articles · Updated · The New Republic · May 26
An April CMIP paper said the old RCP8.5 pathway is now “implausible,” not that the IPCC admitted its climate projections were wrong, contradicting Donald Trump’s social-media claim.
RCP8.5 was designed as a low-probability, high-risk scenario, and researchers say 15 years of data, climate policy shifts and cheaper renewables have mainly made its coal-heavy emissions path less likely.
Scientists cited in the report said that does not invalidate studies using RCP8.5, because worst-case scenarios still help model severe impacts, adaptation needs and possible feedbacks or tipping points.
The dispute matters beyond academic modeling: legal scholars warn opponents of climate regulation could use attacks on RCP8.5 to challenge evidence underpinning climate rules.
Even with RCP8.5 fading, researchers say the world is still headed for roughly 2.5 to 3 degrees Celsius of warming, while staying below 1.5C without overshoot has become effectively impossible.
If the 'worst-case' climate scenario is outdated, what does the new 'most likely' future actually look like?
With old climate scenarios obsolete, how are industries now calculating the true financial risks of climate change?
How can we distinguish between genuine scientific updates on climate change and deliberate misinformation?
From RCP8.5 to Reality: The Science, Politics, and Urgency Behind the 2.4–3.3°C Global Warming Trajectory
Overview
In May 2026, former US president Donald Trump sparked a new controversy by posting on social media that the RCP8.5 climate scenario was 'wrong' and falsely claimed the UN's top climate committee, the IPCC, had admitted this. His statements came just after new emissions scenarios were published for upcoming IPCC reports. Right-leaning media quickly amplified Trump's misrepresentation of both the emissions scenarios and the IPCC's role. This incident highlights how public figures can distort scientific developments, especially during times of change in climate modeling, and how such claims can rapidly spread and influence public understanding.