World's oceans hit highest temperature on record as El Niño intensifies

Global ocean temperatures have reached an unprecedented high, with the average sea-surface temperature hitting 21.1 degrees Celsius on August 22, 2026. This new record, confirmed by Europe's Earth observation agency Copernicus, surpasses the previous peak of 21.09 degrees Celsius recorded in March 2024, continuing a trend observed since daily tracking began in 1979. The timing of this record is particularly significant, as ocean temperatures typically reach their annual maximum earlier in the year, around March and April.

Scientists attribute this record-breaking warmth to a dual impact of human-driven climate change and an intensifying El Niño phenomenon. While decades of accumulated greenhouse gases have caused long-term ocean warming, the current El Niño event is contributing additional heat to an already stressed marine environment. This El Niño is projected to strengthen further in the upcoming months, potentially reaching levels not observed in decades.

The persistent and escalating ocean warmth poses severe threats to marine ecosystems and global weather patterns. Higher temperatures increase the frequency and intensity of marine heatwaves, which can devastate vital habitats like coral reefs and disrupt marine food webs. Furthermore, warmer oceans contribute to sea-level rise through thermal expansion and provide more energy and moisture to storms, enhancing the potential for extreme precipitation and flooding events worldwide.