Climate change driving European marine heatwaves - study

Scientists have concluded that climate change is the primary cause of the unprecedented sea temperatures observed around Europe, with significant implications for marine life and coastal communities. The Mediterranean saw its highest July average temperature ever recorded at 27C last month, while a buoy near Mallorca measured 33C in early August.

The World Weather Attribution group, employing peer-reviewed methodologies, has determined that this human-induced warming has raised Mediterranean temperatures by roughly 2C and Western European seas by approximately 1.4C. This phenomenon poses the risk of drastically altering ecosystems crucial for coastal communities' sustenance and livelihoods, as well as exacerbating extreme weather conditions on land.

According to Claire Bergin, a climate scientist from Maynooth University and co-author of the study, these peak sea temperatures this year in the eastern and western Mediterranean, the Bay of Biscay, and the Iberian coast would have been inconceivable without human-induced climate change. In Ireland and Britain's Celtic Sea, the most extreme temperatures recorded would have been anticipated only once every century in a world devoid of human-induced warming.

Rising sea temperatures intensify coastal humidity and overnight heat, potentially igniting severe storms. Greenhouse gas emissions, primarily from fossil fuel combustion, have elevated the planet's average temperature by about 1.4C since pre-industrial levels, as stated by the World Meteorological Organization. This elevated baseline amplifies the atmospheric high-pressure systems responsible for heatwaves, leading to even hotter conditions.

Consequently, marine heatwaves have caused mass die-offs of species like corals and disrupted food supplies for birds and mammals, sending ripples through food chains. John Bruno, a marine ecologist from the University of North Carolina, warned that many species are struggling to adapt to these drastic changes, as they are rapidly approaching the limits of biological adaptation.

The WWA analysis reveals that about 90% of the Bay of Biscay and 80% of the western Mediterranean experienced marine heatwave conditions this year, a stark contrast to the estimated 40% without global warming.