‘Unheard of’ marine heatwave off UK and Irish coasts poses serious threat
An “unheard of” marine heatwave off the coasts of the UK and Ireland poses a serious threat to species, scientists have warned.
Sea temperatures, particularly off the north-east coast of England and the west of Ireland, 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 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 of England up to 5C above what is usual.
The Met Office says temperatures are likely to remain high because of the emerging El Niño weather phenomenon.
Daniela Schmidt, a professor of earth sciences at the University of Bristol, said: “The extreme and unprecedented temperatures show the power of the combination of human-induced warming and natural climate variability like El Niño.
“While marine heatwaves are found in warmer seas like the Mediterranean, such anomalous temperatures in this part of the north Atlantic are unheard of. They have been linked to less dust from the Sahara but also the North Atlantic climate variability, which will need further understanding to unravel.
The Met Office says temperatures are likely to remain high because of the emerging El Niño weather phenomenon.
Daniela Schmidt, a professor of earth sciences at the University of Bristol, said: “The extreme and unprecedented temperatures show the power of the combination of human-induced warming and natural climate variability like El Niño.
“While marine heatwaves are found in warmer seas like the Mediterranean, such anomalous temperatures in this part of the north Atlantic are unheard of. They have been linked to less dust from the Sahara but also the North Atlantic climate variability, which will need further understanding to unravel.
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 damage caused in these hotspots is also harmful to humanity, which relies on the oceans for oxygen, food, storm protection and the removal of climate-heating carbon dioxide in the atmosphere.
A report by the Met Office says warmer than usual marine temperatures are contributing to a reduction in sea ice. It found the amount of Arctic ice was well below average for the time of year but still above record low levels after near-average ice loss during May. However, Antarctic sea ice extent is exceptionally low, the lowest on record for this date by a wide margin.
Dr Ed Blockley, the lead of the polar climate group at the Met Office, said: “Over recent decades we have seen a sustained loss in Arctic sea ice extent in every month of the year – especially in late summer to early autumn. Although the current Arctic sea ice extent is considerably higher than the record low for the time of year, it is still well below the long-term average.
“Antarctic sea ice has been at very low levels since November 2016. This year we have seen Antarctic sea ice shrink to a record low point for the time of year, following a second successive annual record minimum sea ice extent in February.”
cover photo:thetimes.co.uk
