"Unprecedented" Heatwave - Seas Off Cornwall, Devon, W. Ireland 7F Above Springtime Average Temperatures
The sea off the coast of the UK and Ireland is experiencing an unprecedented marine heatwave with temperatures increasing by as much as 4C above average for the spring in some areas. Marine biologists say the intensity and unprecedented nature of the rise in water temperatures off the coasts of Devon, Cornwall and the west coast of Ireland are very concerning. As human-induced climate breakdown continues to raise global temperatures, the frequency of marine heatwaves is increasing.
“This is unprecedented because it is happening so early in the year,” said Dr Manuela Truebano, from the school of biological and marine sciences at the University of Plymouth. “To see these temperature rises around UK waters at this time of year is quite sobering. Each time it happens we use the word ‘unprecedented’, and I am very concerned at the increase in prevalence and intensity of these marine heatwave events.”
Temperatures in the sea off the south coast of Devon, Cornwall and Ireland have risen by between 2C and 4C above average temperatures for this time of year. Dr Dan Smale, of the Marine Biological Association, said the usual springtime water temperatures would be 11C-12C, but the waters were now at absolute temperatures of 15C-16C.
The UK is increasingly being hit by marine heatwaves, with sea temperatures in June 2023 reaching their highest levels since records began. At the time the warming was labelled as “unheard of”. Truebano said the rise in sea temperatures so early in the spring was even more concerning. The marine heatwave began in March and has continued for almost two months. If the sea temperatures continue to rise into the summer months there are fears of mass die-offs of fish and other marine life.
EDIT
https://www.theguardian.com/environment/2025/may/22/marine-heatwave-sea-temperatures-devon-cornwall-ireland