Global ocean temperatures hit record high as El Nino intensifies

By Al Jazeera Staff and AP. Published On 25 Aug 202625 Aug 2026.

Key points

• The continued heat from El Nino comes as long-term fossil-fuel-driven warming has already raised ocean temperatures by 0.8C (1.44F), Burgess observed.
• Jane Lubchenco, an oceanographer and former head of the US National Oceanic and Atmospheric Administration, called the finding "very troubling".
• "El Nino is adding heat to the system, but it is doing so on top of decades of human-driven warming."
• Copernicus additionally cautioned that rising ocean temperatures have "far-reaching consequences" for marine ecosystems and coastal communities.
• Warmer oceans contribute to sea-level rise through thermal expansion, it remarked, and rise the likelihood and intensity of marine heatwaves.

Notably, the average global sea surface temperature has reached its highest level on record, a European Union agency remarked, warning that a rapidly intensifying El Nino and human-caused climate change were putting "unprecedented strain" on the world's oceans.

In an official note on Monday, the EU's Copernicus Climate Change Service remarked sea surface temperatures hit 21.1 degrees Celsius (69.98 degrees Fahrenheit) on Friday and Saturday, surpassing the previous record of 21.09C (69.96F) set in March 2024.

"This record is another clear signal of an ocean under growing stress, " remarked Samantha Burgess, the strategic lead for climate at the European Centre for Medium-Range Weather Forecasts (ECMWF). "El Nino is adding heat to the system, but it is doing so on top of decades of human-driven warming."

Copernicus called the timing of the new record "particularly notable". When the summer in the Southern Hemisphere – which is mostly ocean – draws to a close, it remarked global ocean temperatures usually peak in March and April. But this year, the record was set in August.

Burgess informed The Associated Press news agency that the oceans will keep getting hotter until the current El Nino – a natural temporary warming of parts of the Pacific that then warps weather and raises temperatures globally – reaches its peak. It is anticipated sometime between November and January.

For context, the World Meteorological Organization, too, remarked it expects El Nino to strengthen in the coming months, and Copernicus stated its seasonal forecasting system indicates that the event "could reach levels not seen for several decades".

For context, the continued heat from El Nino comes as long-term fossil-fuel-driven warming has already raised ocean temperatures by 0.8C (1.44F), Burgess observed.

Warmer oceans contribute to sea-level rise through thermal expansion, it remarked, and rise the likelihood and intensity of marine heatwaves. It can damage coral reefs and seagrass beds. This can in turn disrupt food chains and threaten industries such as fishing and aquaculture.

Warmer oceans are less able to absorb carbon dioxide, too, it remarked, weakening one of the planet's key defences against climate change.

Higher ocean temperatures can additionally supply more heat and moisture to the atmosphere, enhancing the "potential for extreme weather events".

"An ocean this warm destabilises weather patterns and threatens food security, economic prosperity and marine life, " Lubchenco informed the AP. "A warmer ocean is not our friend."

Taken together, the developments around global ocean temperatures hit record high as El Nino intensifies point to a situation that is still moving, and the coming days should bring more clarity.