Scientists have warned that an unusual marine heatwave off the UK and Irish coasts could pose a serious threat to a number of species.
Records show that sea temperatures, particularly off the north-east coast of England and the west of Ireland, are several degrees higher than normal for this time of year.
In addition, the North Sea and north Atlantic are experiencing higher temperatures.
Temperatures have reached an all-time high since Met Office records began in 1850 and the meteorological organisation said temperatures are likely to remain high because of the El Niño weather phenomenon.
Similar heatwaves in other areas have placed huge stress on marine wildlife, resulting in mass mortalities of marine plants and animals, as well as reducing income for fishers, depleting carbon storage and creating long-term habitat loss.
“I always thought they would never be ecologically impactful in the cool waters around UK and Ireland but this is unprecedented and possibly devastating,” Dr Dan Smale from the Marine Biological Association told the Guardian. “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.”
But why are sea temperatures so much warmer than usual? Here’s what you need to know.
Why are sea temperatures warmer?
Rising sea temperatures are caused largely by changing wind patterns, particularly over the eastern Pacific in this case.
Global sea temperatures are affected by deeper, colder waters circulating across the globe, but these strong winds have stopped these waters from upwelling and cooling the surface.
This process is being especially escalated due to climate change, with land temperatures also rising and creating a vicious cycle of rising temperatures off the coast.
What could be the impact of rising sea temperatures?
Water holds far more heat than air, which means that ocean currents are a major carrier of heat around the world.
Indeed, just the top few metres of the world’s oceans store as much heat as Earth’s entire atmosphere.
What’s more, oceans are slower to warm up and slower to cool down than land areas, meaning changes like these are signs of significant disruption.
In terms of the impact on marine life, much of the extra heat is limited to the top 2,000 metres of water but it affects the entire water column and ecosystem below.
This can put immense stress on plants and wildlife. When even one species of plant dies, it can remove a source of food for many species.
What’s more, such an impact on marine wildlife can affect coastal economies, resulting in losses for fishers, tourist companies and more.
