European seas hit record summer heat, jeopardizing fisheries and marine ecosystems

An analysis of satellite and buoy data confirms that European seas recorded their warmest summer since reliable monitoring began in 1982, with temperatures topping 33 °C in places like Mallorca. Marine heatwaves, defined as prolonged periods of unusually high water temperature, are now more common and intense, driven by rising greenhouse-gas emissions. The surge in heat has disrupted long-standing fish stocks in Spain and southern England and facilitated the arrival of species from warmer regions, while kelp forests in the Bay of Biscay have largely vanished.

Local fishermen and scientists are experimenting with kelp-seedling projects to restore habitats, but the broader shift threatens the economic stability of coastal communities. In the North Sea, jellyfish swarms have even forced a nuclear plant to halt operations, underscoring the wide-reaching impacts of the warming seas.