Global ocean temperatures have reached their highest recorded level, driven by human-caused climate change and the growing El Niño phenomenon. According to the European Copernicus climate change service, the average surface temperature outside polar regions hit 21.1C (70F) on Saturday. This surpasses the previous record of 21.09C set in March 2024.

Dr Samantha Burgess of Copernicus described the record as a clear signal of an ocean under growing stress. She noted that while El Niño is adding heat, it is叠加 on decades of human-driven warming. The data, derived from buoys, ships, and satellites, indicates that this peak is occurring earlier than usual for the northern hemisphere's summer cycle.

Dr Jeremy Grist of the National Oceanography Centre warned that breaking records early suggests a strong El Niño. He predicted that global temperature records might be broken again in March or April 2027. Meanwhile, Prof Tim Smyth of Plymouth Marine Laboratory highlighted unprecedented marine heatwaves around the UK and Europe, with the western English Channel seeing temperatures up to 7C above normal.

Scientists emphasize that warmer seas fuel extreme weather, raise sea levels through thermal expansion, and devastate marine habitats like coral reefs. These conditions are increasingly pressuring ecosystems and coastal communities worldwide.