Europe's seas are experiencing a significant and alarming increase in temperatures, warming faster than the global average, according to a new report by World Weather Attribution.
An international team of scientists analyzed sea surface temperatures across four key regions this summer: the Celtic Sea, the Western Mediterranean, the Eastern Mediterranean, and the Bay of Biscay & Iberian Peninsula. The findings indicate marine heatwaves have intensified, with some areas registering temperatures up to 6°C (11°F) above normal.
"Our attribution analysis shows that human–induced climate change has directly added about 2°C of heat to the Mediterranean to date and over 1.3–1.4°C to Western European seas," stated Dr. Claire Bergin, a researcher at Maynooth University, Ireland. "While warmer waters for swimming may sound appealing to beachgoers in cooler countries like mine, the impacts on marine life beneath the surface is more serious."
This warming trend is attributed primarily to human-induced climate change, largely driven by the continued burning of fossil fuels. "Every very extra tonne of carbon we emit pushes Europe's coastal temperatures and ecosystems into uncharted territory," said Professor Thomas Frölicher from the University of Bern.
The report highlights that in most assessed regions, the summer warming exceeded the global average increase of 1.4°C. Specifically, the Celtic Sea saw temperatures around 1.2°C higher than average, while the Mediterranean experienced waters up to 3°C warmer.
These elevated temperatures have severe consequences for marine life and the ecosystems that coastal communities depend on. Professor John Bruno from the University of North Carolina at Chapel Hill explained that extreme ocean heat can lead to mass mortality events for vital species like corals, sponges, and macroalgae, creating cascading effects throughout marine ecosystems. "As ocean temperatures continue to climb, we are rapidly approaching the absolute biological limits of adaptation for many species, threatening biodiversity, fisheries, and coastal food systems."
Furthermore, the warming seas can exacerbate extreme weather events on land. Professor Friederike Otto of Imperial College London noted the significant dependence of many people and industries on stable ocean temperatures. "In our oceans and seas there can be very hard limits for adaptation. The longer we wait with transitioning away from fossil fuels, the higher the price. A price not paid by the rich."