The Intergovernmental Panel on Climate Change (IPCC) was founded 25 years ago to provide authoritative assessments on the emerging problem of climate change. Since its first report in 1990, the IPCC has issued increasingly complex follow-ups about every six years. The climate models that feed into the assessments have grown bigger and better, but researchers have not succeeded in reducing some key uncertainties about climate change. Where the reports have grown most firm is in declaring that humans are causing the world to warm.

Credit: Infographic by Carl de Torres
figure a