Key facts
- Human-caused climate change is the main driver of record-breaking sea temperatures around Europe.
- The Mediterranean Sea averaged 27 C in July, the highest on record.
- Peak sea temperatures near Mallorca exceeded 33 C.
- Marine heatwave conditions have affected up to 90% of the Bay of Biscay and 80% of the western Mediterranean this year.
- Scientists warn of severe consequences for marine ecosystems and coastal communities.
Europe's seas are significantly hotter than normal due to climate change, with some areas reaching 6 degrees Celsius above average this week, according to researchers from the World Weather Attribution consortium. The study found that global warming is the primary driver of this year's marine heat waves, which are impacting ecosystems and coastal communities.
July saw the Mediterranean Sea record its highest average temperature at over 27C, with a buoy west of Mallorca measuring over 33C. The scientists analyzed four regions, concluding that climate change made the Western Mediterranean and Celtic regions 2C warmer, the Iberian waters by 1.4C, and the Irish seas by 1.3C. Without global warming, the extent of marine heat waves would be drastically reduced, affecting only a fraction of the areas currently impacted.
Oceans absorb most of the excess heat from fossil fuel emissions, leading to species migration or die-offs and increased risk of extreme weather. For instance, warming waters have led to octopuses decimating shellfish catches in the UK and jellyfish clogging French nuclear power stations. The warm oceans also supercharge humidity and can fuel storms, contributing to events like the 2024 floods in Valencia.