Ocean heat record broken
The world’s oceans have climbed to their highest recorded daily average temperature, in what experts say is another stark sign of the planet’s warming trend. Data from the EU’s Copernicus Climate Change Service shows the extra‑polar global sea surface temperature reached 21.1°C on 22 August 2026, nudging past the previous record of 21.09°C set in March 2024.
Ocean temperatures normally peak in March and April, after the Southern Hemisphere summer. Hitting a new high in August – when waters should be cooling – has left researchers concerned about the persistence and scale of the heat building across the world’s seas.
“This record is another clear signal of an ocean under growing stress. El Niño is adding heat to the system, but it is doing so on top of decades of human-driven warming…”
Samantha Burgess, Strategic Lead for Climate at ECMWF
This latest figure also tops the previous August record of 20.98°C, logged in 2023, adding to what has already been a year marked by unusually warm oceans and mounting evidence of long‑term climate disruption.