Scientists have sounded the alarm over an unprecedented spike in ocean temperatures around the UK and continental Europe.
Extraordinarily high sea surface temperatures, which haven't been observed for nearly two centuries, have led the National Oceanic and Atmospheric Administration (NOAA) to rank the phenomenon as a Category 4 - "extreme" marine heat wave.
The situation is even more troublesome in some local areas, with temperatures reaching Category 5 - the highest and most critical level on the NOAA scale.
The UK’s Met Office reports show that last May was the warmest since 1850 for the Atlantic Ocean close to the UK. Water temperatures continued to surge in early June due to sufficient sunshine and south-westerly warm winds, explained Aidan McGivern, a Met Office meteorologist.
Scientists are puzzled about the North Atlantic heatwave. One NOAA report revealed that global ocean surface temperatures set a new record in May, marking the second month in a row for this milestone. Brian McNoldy, a hurricane expert from the University of Miami, said the probability of experiencing such elevated sea surface temperatures is 1 in 256,000.
"This is beyond extraordinary," he added.
A persistent marine heatwave in the North Atlantic, predicted to continue until August and possibly the end of the year with diminishing severity, heightens the chance of sustained heatwave conditions across most global oceans this summer. This warming trend has already caused unusual developments in the hurricane season, such as the early eastward formation of Tropical Storm Bret. It could lead to rising sea levels, more intense storms, and increased frequency of marine heatwaves, as currently seen in Europe.
Effects on Local Weather and Marine Ecosystem
The ongoing marine heatwave could prove fatal to marine life if it persists due to the depletion of oxygen in warmer waters, which is essential for their survival. While the temperature rise isn't detrimental for sensitive marine species, it does cause stress.
Experts warn that if water temperatures continue to be 4 to 5 degrees Celsius above average until September, we might see a considerable die-off in key species like kelp, seagrass, oysters, and certain fish, which are not only crucial for the UK's surrounding marine ecosystems but also significantly contribute to regional economies.