UN WARNS SEA LEVEL RISE HAS DOUBLED IN A DECADE

The United Nations has warned that the world's oceans are under severe and accelerating pressure from human activity, with the rate of sea level rise doubling over the past decade. The rate of rise stood at 2mm per year before 2015 and reached 4.3mm per year in 2023. The findings appear in the UN's third World Ocean Assessment, which covers the period from 2021 to 2025. The report, produced by nearly 600 scientists from 86 countries, identifies pollution and large-scale industrial fishing as key cumulative stressors placing ocean systems under severe strain.

The assessment records that 16% of all ocean heat gained since 1955 occurred after 2018, with the greatest warming observed in the Atlantic Ocean and the southern parts of the Indian and Pacific Oceans. The report also notes that widespread biodiversity loss is under way as stressors intensify. Deep-sea ecosystems remain poorly understood, with only 27% of the ocean floor mapped as of 2025. The previous World Ocean Assessment, which covered data up to 2018, had already identified persistent degradation of the marine environment.

UN Secretary-General António Guterres called for urgent global collaboration to protect marine ecosystems, stating that the ocean cannot be treated as limitless. The report acknowledged progress in ocean protection, including a landmark high seas treaty that came into force this year, establishing international rules to govern the two-thirds of the global ocean lying outside national jurisdiction. That treaty sits alongside 56 other ocean protection agreements that the report says have improved the global capacity to protect biodiversity, reduce harmful subsidies and manage marine resources.