The Copernicus Climate Change Service (C3S) announced on Monday 24 August that “the daily global average sea surface temperature (SST) has reached its highest level on record”. On 22 August, the recorded temperature stood at 21.1°C, exceeding the previous record of 21.09°C from March 2024. These measurements have been taking place since 1979.
“This milestone is consistent with the continued long-term warming of the global ocean and the emergence of an extreme El Niño event in the tropical Pacific”, the European observation programme says.
The institute explains that the timing of this temperature reading is particularly notable, because global ocean temperatures generally reach their highest levels in March and April, after the austral summer. That isn’t the case with this new record, which also far surpasses the previous August sea surface temperature record of 20.98°C, set in 2023.
Relentless pressure on the ocean. “This record is another clear signal of an ocean under growing stress,” says Samantha Burgess, Strategic Lead for Climate at the European Centre for Medium-Range Weather Forecasts (ECMWF). “El Niño is adding heat to the system, but it is doing so on top of decades of human-driven warming.”
Copernicus says there are multiple consequences of rising ocean temperatures. It contributes to rising sea levels, increases pressure on marine ecosystems and the food and industrial networks that stem from them, such as fisheries, and increases the risk of extreme weather events, like storms.
Moreover, the El Niño climate phenomenon “could reach levels not seen for several decades”, according to the institute. Panama and El Salvador have already declared a state of emergency due to the lack of water and risk of famine the weather event could cause, while Honduras has placed 80% of its territory on alert.
On 24 August, the global average temperature measured at the sea’s surface reached as high as 21.11°C.
Check daily recorded temperatures: https://aeur.eu/f/n56 (Original version in French by Nadège Delépine)