CMIP7 emissions scenarios out for IPCC AR7

By MatthewDahlhausen @ 2026-09-02T16:46 (+6)

This is a linkpost to https://www.carbonbrief.org/explainer-the-cmip7-emissions-scenarios-and-how-they-explore-future-climate-change

The new CMIP7 emissions scenarios are out for the IPCC's seventh assessment report (AR7). See the CarbonBrief explainer for a full breakdown.

Notable changes:

• The highest 8.5 scenario was dropped and the now "high" scenario has much less warming
• Much of this is because of climate policy and low cost tech; high coal use for electricity is no longer plausible given the low cost of renewables and batteries
• No baseline scenario; instead they show less/current/more climate policy, with a medium scenario with current policy at around 2.9°C of warming
• Scenarios still depend on a lot of carbon-dioxide removal that hasn't scaled yet

The lowest (1.5°C) and highest (4°C+) scenarios are less feasible. That's mixed news - less chance of the worst case scenarios, but also means we are more likely to still have disruptive ~2.5-3°C warming.