Climate scientists have updated their projections for future global warming, and one major conclusion stands out: the former worst-case climate scenario, known as RCP8.5, is no longer considered a plausible future.

The revised framework, published in a 2025 peer-reviewed study and expected to guide the next assessment of the Intergovernmental Panel on Climate Change, reflects changes in global emissions trends, climate policies and clean energy deployment. Scientists say the exclusion of RCP8.5 suggests that international efforts, including the Paris Agreement, have helped slow the growth of greenhouse gas emissions.

Progress, But Not Enough

RCP8.5 had projected global temperatures rising by 3.5°C to 5.5°C by 2100. While that outcome is now viewed as unlikely, the most plausible high-emissions pathway could still lead to around 3.5°C of warming by the end of the century, with temperatures potentially approaching 4°C thereafter.

At the same time, scientists have removed the previous best-case scenario from the range of likely futures. Under the most optimistic pathway now considered plausible, global temperatures would still temporarily exceed the Paris Agreement's 1.5°C target, reaching about 1.7°C before declining.

Rising Costs Of Climate Change

Researchers emphasize that climate models have accurately tracked observed warming trends. Recent studies indicate that climate risks are increasing, even at lower levels of warming.

The economic impacts are already significant. According to the European Environment Agency, climate-related losses in Europe reached €40 billion in 2024. The European Commission estimates that economic output could be 7% lower by 2100 under a high-warming pathway compared with a 1.5°C scenario.

Scientists say the latest projections show real progress, but they also underline the need for faster emissions reductions and stronger climate adaptation measures worldwide.