Overview

• An international Global Tipping Points assessment declares warm-water coral reefs have passed a thermal tipping point after an unprecedented bleaching event since 2023 that affected roughly four-fifths of reefs worldwide.
• The report estimates the coral threshold lies between about 1.0°C and 1.5°C of warming, with a central estimate near 1.2°C, while current global heating is about 1.3–1.4°C, threatening communities that rely on reefs for food, income and coastal protection.
• Authors lower risk thresholds elsewhere, warning the Amazon could tip at around 1.5°C when combined with deforestation, with analyses indicating 22% forest loss could set that limit and roughly 17% already cleared.
• The assessment flags mounting dangers for the Atlantic Meridional Overturning Circulation at warming below 2°C and highlights accelerating ice loss in Greenland and West Antarctica.
• Ahead of COP30 talks in Belém, researchers urge rapid emissions cuts including methane and black carbon, large-scale carbon removal and stronger governance, while noting positive momentum in clean energy such as renewables outpacing coal and rapid growth in EVs and solar.