‘Unheard of’ marine heatwave off Irish coast poses serious threat to plant and fish life
A Oysters Fish To Image Marine Stock Poses Heatwave Seagrass, Particular Kelp, And The Threat
An “unheard of” marine heatwave off the coasts of Ireland and the UK poses a serious threat to species, scientists have warned.
Sea temperatures, particularly off the west of Ireland and the north-east of England,are several degrees above normal, smashing records for late spring and early summer. The North Sea and north Atlantic are experiencing higher temperatures, data shows.
The UK's Met Office said global sea surface temperatures in April and May reached an all-time high for those months, according to records dating to 1850, with June also on course to hit record heat levels.
The US National Oceanic and Atmospheric Administration has categorised parts of the North Sea as being in a category four marine heatwave, which is considered “extreme”, with areas off the coast up to 5C above what is usual.
It is likely to remain high due to the emerging El Nino weather phenomenon.
Dr Dan Smale from the Marine Biological Association has been working on marine heatwaves for more than a decade and was surprised by the temperatures.
He said: “I always thought they would never be ecologically impactful in the cool waters around UK and Ireland but this is unprecedented and possibly devastating. Current temperatures are way too high but not yet lethal for majority of species, although stressful for many … If it carries on through summer we could see mass mortality of kelp, seagrass, fish and oysters.”
Daniela Schmidt, a professor of earth sciences at the University of Bristol, said the "extreme and unprecedented temperatures" show the power of climate change.
She said similar events in other parts of the world have led to mass mortalities of marine plants and animals.
Marine heatwaves are becoming more numerous, a 2019 study found, with the number of heatwave days having tripled in the past couple of years studied.
The number of heatwave days rose by more than 50% in the 30 years to 2016, compared with 1925-54. Scientists said at the time the heat destroyed swathes of sealife “like wildfires take out huge areas of forest”.
- The Guardian