The ocean has been changing rapidly, with the Arctic seeing sharp shifts and parts of Europe recording marine heatwaves more than 4.6C above normal in 2024, according to a new report from the EU’s Copernicus programme.
The findings come from the tenth Ocean State Report, published by Copernicus Marine Environment Monitoring Service, which uses data going back to 1960, the European Commission announced on Wednesday.
Average global sea level rose by about 4.2mm a year from 2012 onwards, with rising temperatures cited as the driver, according to the report.
In the Arctic, sea-ice extent fell by roughly 490,000 square kilometres per decade between 1979 and 2025 — an area almost as large as Spain — the report said.
It added that the loss of ice has led to more wind and waves, leaving around 60% of Arctic coastal infrastructure vulnerable to erosion and sea-level rise.
The Mediterranean and Black Sea recorded “record-breaking” marine heatwaves in 2024, with temperatures more than 4.6C above normal. Marine heatwaves are prolonged periods of unusually high sea temperatures.
Small islands and rising seas
Small Island Developing States saw 65% of their combined Exclusive Economic Zones — the sea areas where a country has rights over marine resources — face accelerating sea-level rise since 1999 because of ocean warming, the report said.
The annual Ocean State Report is used to monitor ocean conditions and their effects on ecosystems, food security, economies and coastal communities.
“The Ocean State Report once again highlights the scale and urgency of the challenges facing our ocean,” said Andrius Kubilius, the European Commissioner for Defence and Space.
Costas Kadis, the European Commissioner for Fisheries and Oceans, stated that the findings covered “record-breaking marine heatwaves in the Mediterranean and Black Seas”, “accelerating sea-level rise” and “dramatic ice loss in the Arctic”.
