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
Warmer in Lapland than it is here. Arctic Circle sees 25 °C. . . Thursday 4 June 2026
On the left is the Temperature Radar for Europe; on the right is a picture of a lake in Finland surrounded by woodland.
Thursday 4 June 2026

Arctic Circle sees 25 °C

Warmer in Lapland than it is here
Spring records for England & Wales. Above-average warmth. . . Tuesday 2 June 2026
Split graphic showing a European temperatures anomaly map on the left with widespread warmer-than-average conditions, and a UK and Ireland heat map on the right displaying intense heat with temperatures exceeding 30 °C.
Tuesday 2 June 2026

Above-average warmth

Spring records for England & Wales
Unseasonably windy start to summer. Autumn-like gusts. . . Wednesday 3 June 2026
Wind forecast map of the UK and Ireland showing a low-pressure system west of Ireland, widespread orange wind zones, airflow streamlines, and gusts reaching 45 mph in parts of Ireland and southern Britain.
Wednesday 3 June 2026

Autumn-like gusts

Unseasonably windy start to summer
All weather news
This might also interest you
A frozen start to the weekend. Icy conditions. . . Friday 13 February 2026
UK temperature map dated 14.02 showing widespread subzero values in blue shading, with readings such as −4 in Glasgow, −3 in Dublin, and −2 in London, alongside a blue thermometer icon.
Friday 13 February 2026

Icy conditions

A frozen start to the weekend
Seasonal warmth between spring thunder. Your weather - Your shots. . . Sunday 19 April 2026
Split image showing coastal sunset with layered lenticular clouds over rooftops and palm trees on the left, and a green valley with river and hills under soft daylight on the right.
Sunday 19 April 2026

Your weather - Your shots

Seasonal warmth between spring thunder
Bright and warm conditions take hold. Spring-like outlook. . . Thursday 23 April 2026
Split UK map showing warm temperatures up to 21 degrees in orange on the left and clear sunny conditions with temperatures from 12 to 18 degrees on the right, with sun icons across the country.
Thursday 23 April 2026

Spring-like outlook

Bright and warm conditions take hold
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