Human activity, which causes climate change, has become the main driver of record temperatures in the seas around Europe. This is the conclusion reached by scientists from the World Weather Attribution group.
In July, the average temperature in the Mediterranean Sea reached 27 degrees Celsius—the highest in recorded history. In early August, a buoy off the coast of Mallorca recorded 33 degrees.
The analysis showed that warming added about 2 degrees to temperatures in the Mediterranean Sea and approximately 1,4 degrees to the seas of Western Europe. Peak temperatures in the eastern and western parts of the Mediterranean, as well as in the Bay of Biscay and off the Iberian coast, would have been virtually impossible without the anthropogenic factor.
In the Celtic Sea, off the coasts of Britain and Ireland, the most extreme values are now expected once a century instead of their previous rarity.
Scientists warn of serious consequences for marine ecosystems and coastal communities. Warmer waters could completely alter the familiar ecosystems upon which local residents depend for food and income.
"This has the potential to completely restructure the ecosystems that coastal communities rely on and trigger devastating extreme weather events on land," noted climatologist Claire Bergin from Maynooth University in Ireland.
Hot seas increase humidity and nighttime temperatures on the coast, and can also intensify storms later in the year. About 90% of the Bay of Biscay and 80% of the western Mediterranean experienced marine heatwave conditions this year—without global warming, this share would have been closer to 40%.
Marine ecologist John Bruno from the University of North Carolina points out that some species are migrating north in search of cooler waters, but not all are capable of adapting. How quickly will we reach the absolute biological limits for many species?
Greenhouse gas emissions, primarily from burning fossil fuels, have raised the planet's average temperature by approximately 1,4 degrees above pre-industrial levels. This creates a new, hotter baseline for the atmospheric systems that cause heatwaves.
