Debunking Trump's Misleading Claims About Climate Scenarios
Recently, former President Donald Trump took to social media to declare 'good riddance' to a specific climate scenario, RCP8.5, claiming it was 'wrong, wrong, wrong' and that the UN's top climate committee had admitted this. This sparked a wave of misinformation. Here, we separate fact from fiction: the IPCC never owned or disowned any scenario, and while RCP8.5 has been updated, the new pathways still show alarming warming. Dive into the truth behind the headlines.
What Did Trump Actually Claim?
On May 16, Trump posted on Truth Social that the 'top climate committee' of the UN had 'just admitted' the RCP8.5 scenario was 'wrong, wrong, wrong' in block capitals. He framed this as a vindication, but his claim is false. The IPCC does not create or control climate scenarios; it assesses scientific literature. No IPCC document has ever labeled any scenario as 'wrong'. The scenario in question, RCP8.5, was developed by the scientific community years ago and has been widely used in research. Trump's message quickly spread through right-leaning media, which often misattributed the scenario to the IPCC itself.
What Is RCP8.5 and Why Does It Matter?
RCP8.5 stands for Representative Concentration Pathway 8.5, a high-emissions scenario where carbon dioxide concentrations rise steeply through 2100. It was designed in 2010 to explore a future with very high fossil fuel use and minimal climate action. It became a benchmark for worst-case warming projections. However, it has been criticized for assuming unrealistic levels of coal consumption and population growth. Despite this, it has been valuable for studying extreme impacts and for stress-testing climate models. Recently, the scientific community has shifted to newer scenarios, called Shared Socioeconomic Pathways (SSPs), which include a broader range of futures.
Why Is RCP8.5 So Hotly Debated?
The debate centers on whether RCP8.5 was ever a plausible pathway. Critics argue it overestimated future coal use and ignored rapid renewable energy growth. Some climate skeptics use this to claim all climate projections are unreliable. However, RCP8.5 was never meant to be a prediction; it was a boundary scenario to examine high-end risks. Many scientists defend its continued use for understanding worst-case risks, especially for tipping points. The controversy intensified when Trump seized on it, but the IPCC's role remains unchanged: it evaluates all scenarios, not just one. The new SSPs reflect updated economic and technological trends, but still show the world is heading toward 2.5-3°C of warming – far above the Paris Agreement goals.
How Has RCP8.5 Been Replaced?
Starting around 2020, climate modelers introduced the Shared Socioeconomic Pathways (SSPs) to replace RCPs. These combine different emissions trajectories with storylines about population, inequality, and technology. The highest new scenario, SSP5-8.5, has lower emissions than RCP8.5 because it reflects more realistic coal constraints. Importantly, the new set no longer includes a 'business as usual' continuation of unchecked emissions; instead, even the high-end scenarios assume some climate policies. This has been misinterpreted as the IPCC 'quietly scrapping apocalyptic forecasts', but it's simply a normal update in climate science. The real concern, as one author told Carbon Brief, is that limiting warming to 1.5°C now appears impossible without a significant overshoot. The new scenarios also show that current policies still lead to 2.5-3°C warming – a level the UN calls 'catastrophic'. So the 'good riddance' is misplaced: the problem hasn't gone away.
How Is the IPCC Involved in These Scenarios?
The Intergovernmental Panel on Climate Change (IPCC) assesses peer-reviewed science but does not generate its own scenarios. It uses those developed by the wider scientific community, like the RCPs and now the SSPs, to project climate impacts. Trump falsely implied the IPCC 'admitted' RCP8.5 was wrong. In reality, the IPCC's reports have always considered multiple scenarios, and they have noted that RCP8.5 is a high-end pathway among many. The new scenarios were produced by the ScenarioMIP project within CMIP6, unrelated to any IPCC 'admission'. The IPCC will use these new scenarios in its upcoming reports, but it does not 'own' them. Thus, Trump's claim misrepresents both the process and the science.
What Do the New Scenarios Tell Us About Future Warming?
The new SSP scenarios paint a sobering picture. Even the most optimistic pathways require swift, deep emission cuts to meet the 1.5°C target, and even then, a temporary overshoot is likely. The highest scenarios, like SSP5-8.5, still project warming of 4-5°C by 2100, similar to old RCP8.5. More crucially, current global policies are consistent with about 2.5-3°C warming, as noted by an author of the new scenarios. This level is described by the UN as catastrophic, leading to extreme heatwaves, sea level rise, and biodiversity loss. So while the specific numbers have been updated, the trend remains alarming. The science continues to emphasize the urgency of action, not that the threat has been exaggerated.