Sea temperatures around the UK and Ireland have dramatically increased in recent weeks. Some areas are now 4°C warmer than average, sparking concerns for marine life and swimmers. This marine heatwave is most intense off the west coast of Ireland and in pockets near Cornwall and Devon.
According to scientists at the National Oceanography Centre and the Met Office, sea temperatures in April and early May were the highest recorded in 45 years. Climate change is warming oceans globally, making marine heatwaves more likely. Experts anticipate 2025 to be one of the hottest years on record.
The entire west coast of the UK is roughly 2.5°C above average, with Scottish waters 2-3°C warmer than usual. One location off Tyne and Tees recorded temperatures 5°C higher than average. The average sea surface temperature reached 12.69°C on May 19, exceeding the UK's May marine heatwave threshold of 11.3°C.