Global Ocean Health Reports Flag Critical Decline and Rising Threats

A five‑year scientific assessment involving 550 experts from 86 nations concluded that the world’s oceans have reached a critical point. The report warns that marine ecosystem degradation now directly threatens climate regulation, food security, economies and the safety of billions of people. Sea‑level rise has accelerated, with the annual increase climbing from about 1.9 mm before 2015 to 4.3 mm in 2023, and 16 % of ocean warming since 1955 has occurred after 2018. Coral reefs are disappearing rapidly – roughly 80 % of Caribbean reefs have vanished since the 1970s and up to 90 % could be lost if warming exceeds 1.5 °C. Pollution, especially plastic, and acidification are also intensifying.

The Starfish 2026 Ocean Barometer, published by Mercator Ocean International, reinforces these findings. Compiled by 29 researchers from 14 countries, it shows worsening trends in surface‑water warming, deoxygenation, acidification, sea‑level rise and biodiversity loss, despite the recent entry into force of the United Nations high‑seas protection treaty (BBNJ) in January 2026. As marine scientist Marina Lévy noted, “the pressures we exert on the ocean keep intensifying, and the state of the ocean is deteriorating compared with last year.” The treaty’s concrete benefits remain unmeasured, underscoring the need for coordinated, decisive action to avoid an irreversible crisis.