Sea temperature records broken in Western Europe in marine heatwave

Words by ITV News Senior Science Producer Rhiannon Hopley

Western Europe has had its hottest June on record but it is not just the land where we are feeling the heat.

The UK was among several countries to break land temperature records in June but off the coast an unseen rise was also happening.

Outside of the poles, global sea surface temperatures were at their highest ever for June.

Since February, sea temperatures have been steadily intensifying – particularly on the south coastline of the UK.

By the end of May, after our first heatwave of the year, sea temperatures were already 2C warmer than usual for the time of year.

Hot weather in Southend-on-Sea, Essex, during last month’s heatwave. / Credit: PA

By the end of June, parts of UK waters were up to 5C above average.

A network of 72 buoys located around the UK’s waters has picked up some temperatures considerably above normal at a number of sites at the start of July.

These included Hastings which was 5.3C above usual.

The Met Office has warned that the long-lasting UK marine heatwave is likely to reach extreme levels this week, as the increased ocean temperature affects the marine species living in it.

Professor John K. Pinnegar, the Principal Scientist and Lead Advisor at the Centre for Environment, Fisheries and Aquaculture Science (CEFAS) warned of dire consequences for marine life in UK waters.

He said: “Prolonged periods of unusually warm sea temperatures can lead to shifts in fish populations, damage important habitats such as seagrass and kelp, and increase the likelihood of harmful algal blooms.

“These changes can result in mass-mortality events for some marine species and alter the distribution of commercially-important fish and shellfish.”

The Marine Climate Change Impacts Partnership estimates that we may lose cod from the southern waters of the UK as they heat up.

The UK has already seen an rise in warmer water species like the octopus.

Last year saw brown crab and scallop catches fall by over 50% compared to recent averages and lobster catches drop by 30% after the introduction of this previously unseen predator.