In June, the Earth’s average ocean temperature reached unprecedented levels, as reported by two European Union Earth monitoring organizations, the Copernicus Climate Change Service and the Copernicus Marine Service.
On June 21, ocean temperatures soared to around 21 degrees Celsius (approximately 70 degrees Fahrenheit), marking a new record for this period, as announced by the two services in a joint statement. This surpassed previous records set in 2023 and 2024. Rising ocean temperatures pose a threat to marine life and could contribute to further sea level increases.

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This temperature spike is significant as the planet is entering an El Niño phase, characterized by a cyclical shift in ocean and wind patterns resulting in unusually warm ocean conditions. Recently, after weeks of forecasts, the U.S. National Oceanic and Atmospheric Administration (NOAA) confirmed the presence of El Niño, predicting it will likely intensify between November 2026 and January 2027. As reported by Scientific American at the time, this year’s event could be among the largest recorded, potentially further elevating ocean temperatures.
Experts anticipate more heat records to be broken soon. “With ocean temperatures at these levels and El Niño on the horizon, we are likely to see more temperature records fall in the coming months,” stated Carlo Buontempo, the director of the Copernicus Climate Change Service, in the same statement.
“Current conditions could indicate the beginning of a new phase, leading, once more, to uncharted territory,” he added.
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