Overview

• An international team of about 160 scientists released the Global Tipping Points Report 2025, concluding tropical warm‑water reefs have almost certainly passed a catastrophic threshold.
• At an estimated 1.4°C of global warming in 2025, reefs are undergoing unprecedented mortality during a two‑year mass bleaching event documented by the authors.
• The report warns the vast majority of reefs would be condemned at 1.5°C, a level scientists say could arrive within years without drastic cuts to greenhouse gas emissions.
• The loss of reefs threatens the livelihoods of hundreds of millions of people and jeopardizes roughly one million marine species, with an IUCN assessment finding 44% of coral species at risk of extinction.
• The publication was timed to press negotiators at a pre‑COP in Brasília and ahead of COP30 in Belém, as the authors and UN leadership call for immediate, far‑reaching climate action and flag other looming tipping points in ice sheets, ocean circulation and the Amazon.