United Nations Framework Convention on Climate Change

Stories

Climate scientists drop worst-case warming scenario from new model framework

As of May 2026: Tracks national pledges; projects 2.3–2.7°C under current commitments

The scenario long used as climate change's 'business as usual' no longer counts. In April 2026, the team building the next generation of global climate models removed SSP5-8.5 (the high-emissions track behind most '4-5°C by 2100' headlines) from CMIP7, which will feed the IPCC's seventh assessment report.

Updated May 31

US becomes first nation to quit foundational climate treaty

Rule Changes

As of May 2026: Losing its largest historical emitter and second-largest economy

On January 7, 2026, Trump signed a memorandum directing US withdrawal from the UN Framework Convention on Climate Change—the 1992 treaty George H.W. Bush signed and the Senate unanimously ratified. The US is the first of 198 parties to exit. The UNFCCC underpins all international climate negotiations (unlike the Paris Agreement, which Trump also exited), and withdrawal takes effect one year from notification.

Updated May 19