The Copernicus Climate Change Service warned on May 8, 2026 that global ocean temperatures were nearing new record highs, with April sea surface temperatures close to those of 2024 and new records anticipated soon in May. Samantha Burgess, the service’s deputy director, described the trend as deeply alarming and noted the potential for an impending El Niño to intensify the situation and extreme weather events.
According to Copernicus data, the average sea surface temperature over the extra-polar global ocean in April 2026 stood at 21.00 degrees Celsius. This marked the second-highest value on record for the month, just behind the 21.04 degrees Celsius registered in April 2024. The temperatures inched closer to records throughout the month as the Pacific began transitioning toward El Niño conditions. Record highs occurred in regions from the central equatorial Pacific to the western coasts of the United States and Mexico, corresponding to strong marine heatwave conditions.
Burgess said, “It is only a matter of days before new ocean heat records are broken in May.” The Copernicus report highlighted persistent planetary warming even prior to the anticipated El Niño arrival. Subsequent monitoring by the service showed that May 2026 ultimately recorded the second-highest sea surface temperatures for the month at 20.90 degrees Celsius according to its June bulletin.
The U.S. National Oceanic and Atmospheric Administration declared in June 2026 that El Niño conditions were present. NOAA figures show sea surface temperatures in key Pacific regions surpassing the 0.5 degrees Celsius threshold defining the phenomenon. Forecasts from the agency indicate the pattern will strengthen into the Northern Hemisphere winter of 2026-27.
Elevated ocean temperatures contribute to more frequent and intense marine heatwaves, a Mercator Ocean International bulletin for April 2026 found. The analysis reported that 76 percent of the global ocean experienced above-average sea surface temperatures that month. Such conditions have historically led to disruptions in marine life and weather patterns across multiple continents.
Copernicus Climate Change Service records indicate that global warming reached an estimated 1.43 degrees Celsius in May 2026 relative to pre-industrial levels. The service, implemented by the European Centre for Medium-Range Weather Forecasts, provides ongoing assessments of these climate indicators. Its data has consistently shown oceans absorbing much of the excess heat from greenhouse gas emissions over recent decades.
The World Meteorological Organization has previously stated that developing El Niño events can raise global temperatures and alter rainfall distributions. In the current cycle, this combines with long-term warming trends to heighten risks of extreme events. Copernicus continues to issue monthly climate bulletins detailing these evolving conditions.
