Climate change is cooking Europe’s oceans, scientists find

Europe's seas are experiencing record-breaking temperatures due to climate change, according to researchers. The Atlantic and Mediterranean regions are far hotter than normal, with some areas reaching 6 degrees Celsius above average. Global warming is the primary driver behind the high ocean temperatures, as scientists from the World Weather Attribution consortium found.

The extreme heat harms marine species, increases jellyfish populations, and raises the risk of destructive storms later in the year. Catherine Gregory, a climate scientist, stated that the average temperature of the Mediterranean Sea in July was the highest on record. The researchers used peer-reviewed methods to analyze four regions, finding that the conditions were the most extreme July marine heat wave conditions in the record for the Western Mediterranean, the Celtic region, and the Bay of Biscay-Iberian Peninsula region.

Climate change made the Mediterranean regions 2°C warmer, the Iberian waters 1.4°C warmer, and the Irish seas 1.3°C warmer. This increased ocean heat has expanded marine heat waves dramatically, with 90% of the Bay of Biscay and 80% of the Western Mediterranean experiencing hot temperatures this year. In contrast, without global warming, only 40% of each region would have been affected.

Oceans absorb most of the excess heat produced by burning fossil fuels, pushing species to relocate and stressing those that cannot move, such as corals or seagrasses. Fishermen in the UK have noticed octopuses spreading north in warmer waters, impacting shellfish catches. In France, jellyfish are clogging nuclear power stations.

Marine heat waves also intensify extreme weather threats to coastal communities by supercharging heat and humidity along shores and building up moisture for storms.