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Sargassum threatens: A blob larger than the US in Atlantic

06:00
16 March 2023

Sargassum threatens
A blob larger than the US in Atlantic

Sargassum covering a beach in Barbados in summer of 2022.Sargassum covering a beach in Barbados in summer of 2022. - © picture alliance

Seaweed often smells bad and creates inconveniences for the little ones trying to play on the sand. But is it harmful?

Florida beaches have been especially affected in recent years by an influx of seaweed, as the warmer waters and wind currents have brought more of this sargassum to the beaches.

Sargassum is a type of brown algae that takes a very long time to sink to the bottom of the sea and travels in large masses on the surface of the sea.

Many animals feed and live in the sargassum that often travels cross-continent. But once it loses buoyancy, the algae sinks to the sea floor, becoming a food source for other animals.

However there is currently a large mass of sargassum travelling west over the Atlantic. This mass is wider than the United States, covering over 8000 km. Scientists expect that if this sargassum reaches the Florida coast, it will be around June.

In recent weeks, Key West has experienced rafts of it. Southwest Florida is also at threat of receiving mass amounts, but from the Yucatan Peninsula, which has also experienced gigantic amounts of sargassum in recent years.

Is it harmful?

Sargassum floating on the sea is not harmful, but does become a nuisance piling up on the beach. As the algae rot however, it releases hydrogen sulphide, which is often harmful to our respiratory systems.

Large amounts of seaweed can also block waterways. During summer 2022, an unusually large amount of sargassum caused water shortages in St. Croix, which prompted a state of emergency for the U.S Virgin Islands.

Weather & Radar editorial team
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