Home
Weather Dublin
WeatherRadar
RainfallRadar
TemperatureRadar
WindRadar
LightningRadar
Weather News
Editor's Pick
Discover the app
Weather widget
Contact us
Apps
    Home / Editor's Pick /

    Marine heatwaves: Jellyfish thrive in the UK

08:00
11 November 2023

Marine heatwaves
Jellyfish thrive in the UK

Crystal jellyfish (Aequorea victoria) often found in warmer waters.
Crystal jellyfish (Aequorea victoria) often found in warmer waters. - © picture alliance

Jellyfish sightings in the UK have soared 32% in the last year, due to our warming waters.

From October 2022 to September 2023, jellyfish sightings have soared 32% along UK coasts. The bulk of these sightings have been on the UK's Atlantic west coast, particularly around Cornwall and Wales.

Species such as barrel jellyfish, Lion's mane, Portuguese man o' war, moon and compass jellyfish have all been spotted, including crystal jellyfish, which are more commonly known to warmer waters.

The hot weather in recent months, particularly in June, created marine conditions for the species to thrive in the UK.

Marine heatwaves

We're all familiar with the idea of a heatwave, but a marine heatwave is much less visible yet equally concerning. Marine heatwaves are periods of unusually warm ocean temperatures that can last anywhere from days to months.

Warmer waters due to marine heatwaves can severely impact marine ecosystems, creating nutrient-deficient "ocean deserts" that make it challenging for marine life to survive.

These temperature spikes are linked to a range of disruptions, from coral bleaching and altered fish migration patterns to the degradation of vital kelp forests along the coast.

That being said, it has led to a positive influx of new jellyfish species to UK coasts, though this could have knock-on implications on the marine ecosystem.

Scientists are unsure if the new species are a short-term result of the marine heatwaves, or a longer-term shift in their northward range as waters warm on average.

Oceans reach record high temperaturesread more
Weather & Radar editorial team
More on the topic
Heat warnings cover much of Ireland. Until the weekend. . . Thursday 16 July 2026
Temperature map of Ireland showing warm to hot conditions nationwide, with temperatures ranging from 27°C in Galway to 23°C in Dublin. A heat warning symbol to the west indicates elevated temperatures.
Thursday 16 July 2026

Until the weekend

Heat warnings cover much of Ireland
Cooler nights and lower dew points. Less oppressive heatwave. . . Thursday 9 July 2026
Split image showing the London skyline in hazy golden sunset light in the left and an overnight temperature map of the UK and Ireland on the right, with minimum temperatures ranging from 13°C in northeast Scotland to 18°C in southern England.
Thursday 9 July 2026

Less oppressive heatwave

Cooler nights and lower dew points
Heatwave keeps a firm grip on Europe. Around 40°C in places. . . Monday 13 July 2026
A collage featuring a temperature radar map of Europe and a fire-fighting aircraft in action over a forest fire. In the centre, a heat symbol warns of persistently high temperatures.
Monday 13 July 2026

Around 40°C in places

Heatwave keeps a firm grip on Europe
All weather news
This might also interest you
New records for England and Wales. Broken again tomorrow?. . . Thursday 25 June 2026
Temperature map of southwest Britain on 25.06 showing extreme heat across southern Wales and southwest England, with Bute Park in Cardiff highlighted at 34.2°C and Yeovilton at 36.4°C amid widespread deep red heat zones.
Thursday 25 June 2026

Broken again tomorrow?

New records for England and Wales
Flooding, gales, and heavy snow. Storm Chandra. . . Tuesday 27 January 2026
Split image showing aerial flooding in a town with muddy water covering roads on the left, and a rural road on the right blocked by heavy snowfall with vans stopped and a person walking in snow.
Tuesday 27 January 2026

Storm Chandra

Flooding, gales, and heavy snow
Turbulent weather in the Canary Islands. Storm and rain. . . Friday 12 December 2025
Weather graphic showing rain and wind fields over the Canary Islands and a central warning symbol.
Friday 12 December 2025

Storm and rain

Turbulent weather in the Canary Islands
All articles
Weather & Radar

Weather & Radar is also available on

Google Play StoreApp Store

Company

Contact us Privacy Policy Legal info Accessibility statement

Services

Uploader

Socials

facebooktwitteryouTubelinkList