Global sea surface temperatures have reached record levels for this time of year. This is evident from the data collected by the Copernicus Climate Change Service and the Copernicus Marine Service. The measurements reveal that on June 21st, a temperature of 20.86°C was recorded, surpassing the 20.83 degrees measured in 2023 and 2024. "Unprecedented warming," according to the officials of this European land monitoring agency.
This new record in sea surface temperature for the month of June has not come as a surprise among climate scientists, who argue that it was predictable due to the combination of two phenomena: on one hand, the warming conditions brought about by the onset of the natural phenomenon of El Niño in June. On the other hand, unusually high sea surface temperatures have been observed in various oceanic regions in recent months.
These results add to a warming trend in the sea observed in recent years. Over the past three years, the global ocean temperature outside the polar regions has been between 0.35 and 0.73°C above the long-term average. And this June, these anomalies have reached record levels for this time of year.
"The current conditions could indicate the beginning of a new phase that may lead us, once again, into uncharted territory. With ocean temperatures at these levels and El Niño on the horizon, it is likely that temperature records will continue to be broken in the coming months," warned Carlo Buontempo, director of the Copernicus Climate Change Service at the European Centre for Medium-Range Weather Forecasts (ECMWF), in a press release.
According to this expert, "the fact that the Copernicus Marine Service data reaches the same conclusion through independent methods demonstrates the strength of European science and highlights why having open and rigorous data is more important than ever today."
Additional energy for storms
The warm sea can have various effects. In fact, Copernicus scientists anticipate that this record will have consequences "for both weather patterns and global climate and marine ecosystems."
As explained in their report, "higher ocean temperatures keep the atmosphere warm for longer, provide additional energy to storms, and increase evaporation, which enhances the potential for extreme rainfall and flooding. Ocean warming also contributes to rising sea levels and melting ice, as well as exerting increasing pressure on marine ecosystems."
Additionally, high sea surface temperatures are also associated with more frequent and intense marine heatwaves, periods of abnormally high ocean temperatures that disrupt ecosystems and fisheries, affect coastal economies, and can intensify episodes of extreme heat in nearby land areas. "Furthermore, an El Niño event constitutes an additional source of heat for the atmosphere, raising global temperatures and altering weather patterns worldwide," they warn.
However, the analysis also points out that "it remains to be seen whether this increase above usual levels will be temporary or if it anticipates the conditions that will prevail in the coming months."
Although reaching record temperatures for this time of year is significant, they consider it consistent with the onset of the El Niño episode — announced by the World Meteorological Organization (WMO) on June 2nd and declared by the National Oceanic and Atmospheric Administration of the United States (NOAA) on June 11th — as well as with the record sea surface temperatures recorded in the North Pacific in the previous months.