Tipping Points: When the Earth Can't Go Back

Key takeaways

• A tipping point is the moment after which a system (a reef, an ice sheet, a forest) can no longer come back by itself; feedback loops push it over.
• From 2023 to 2025, about 84% of the world's coral reefs were hit by bleaching-level heat, and the Global Tipping Points Report 2025 says warm-water reefs have probably already passed their tipping point.
• Since 1993 the sea has risen about 10 cm, and the yearly rise has more than doubled (about 2 mm to more than 4 mm a year); the great ice sheets may start an unstoppable melt at around 1.5°C.
• Since 2010, the water flowing back into the Tonle Sap has been nearly a third lower on average, and dams, drought, sand mining, forest cutting and overfishing together may push the lake toward a tipping point.
• Tipping points can also go the good way: solar module prices fell about 90% from 2010 to 2024 and more than 1 in 5 new cars sold in 2024 was electric; every tenth of a degree avoided matters.