Key facts
- The world's oceans reached a record average surface temperature of 21.1C (70F) on Saturday.
The world's oceans have reached their highest recorded average surface temperature of 21.1C (70F), surpassing previous records set in March 2024. Scientists attribute this to human-caused climate change amplified by the growing El Niño phenomenon, warning of consequences like extreme weather and harm to marine life.
The record-breaking ocean temperatures signal a critical escalation in the impacts of climate change, threatening to intensify extreme weather events, accelerate sea-level rise, and devastate marine ecosystems, with broad implications for global climate stability and coastal communities.
The world's oceans have recorded their highest-ever average surface temperature, reaching 21.1C (70F) on Saturday, according to data from the European Copernicus climate change service. This figure slightly surpasses the previous record of 21.09C observed on multiple days in March 2024.
Scientists attribute this unprecedented warmth to a combination of long-term human-caused climate change and the intensifying El Niño weather phenomenon. Dr. Samantha Burgess, deputy director of Copernicus, stated that this record is a clear signal of an ocean under growing stress, with El Niño adding heat to an already warming system.
The data, collected from buoys, ships, and satellites measuring temperatures up to 10 meters below the surface, is particularly concerning due to its timing. Ocean temperatures typically peak in March or April, corresponding to the end of the southern hemisphere's summer. The current August record, when El Niño is still building, suggests that ocean temperatures could continue to climb, potentially into 2027.
This widespread ocean warmth has significant implications, including the potential to supercharge extreme weather events by providing storms with extra moisture and energy. It can also intensify coastal heatwaves and contribute to rising sea levels as water expands when heated. Furthermore, intense ocean heat poses a severe threat to marine ecosystems, such as coral reefs, and the communities that rely on them.