The Great Atlantic Sargassum Belt
  Sargasso Sea, with major currents in the North Atlantic in white
[1]

The Great Atlantic Sargassum Belt is a mass of Sargassum in the Atlantic Ocean, and is the largest macroalgae bloom in the world.[2][3]

History

The development of the belt 2011–2018

This Sargassum was first reported by Christopher Columbus in the 15th century but recently appeared in 2011 in the Atlantic.[4]

As of 2023, the belt is estimated to weigh about 5.5 million metric tonnes and extends 5,000 miles (8,000 km), stretching from West Africa to the Gulf of Mexico.[5][6]

“I try to shy away from the term blob. That’s not really what it is,” says Barnes, who says that the Great Atlantic Sargassum Belt is really a series of many small blobs with individual patches that are as large as an acre. Smushed together, he adds, it would be roughly the size of Delaware.

— National Geographic, March 2023[6]
A 1 km (0.62 mi) wide patch of sargassum in the Caribbean Sea

Effects

Due to the smell, the attracted insects, and the sheer amount of it piling up on beaches, the Sargassum Belt has a negative impact on communities in the Caribbean, and West Africa.[7] When the Sargassum dies after about 48 hours on land, it releases hydrogen sulfide, a toxic gas. The sulfide can irritate eyes, nose and throat and has a smell akin to that of rotting eggs.[8] The sulfide also can affect people with respiratory problems, including asthma.[9] In 2022, the largest bloom on record was recorded, causing Guadeloupe to issue a health alert, as well as the US Virgin Islands issuing a state of emergency, requesting help from FEMA.[citation needed]

By June 2023 clumps of Sargassum had begun reaching Florida, prompting marine biologists at the Florida Atlantic University Harbor Branch Oceanographic Institute to issue a warning against the presence of Vibrio bacteria on the algae.[10] The bacteria stick to plastic debris that gets tangled in the algae, risking both wildlife and humans.[11]

Cause

The buildup of Sargassum is caused by nutrients flowing into the Atlantic from water discharged by the Amazon and upwelling currents off West Africa. The Sargassum Belt, while in the Sargasso Sea, is different, composed of different morphological types of Sargassum. The Sargassum Belt has also been found to possess lower biodiversity than the Sargasso Sea and is mainly composed of more highly nutrient-efficient organisms.[12]

The Sargassum Belt forms in the North Atlantic Gyre as currents push the material into one mass, similar to the North Atlantic garbage patch.[citation needed]

See also

References

  1. ^ López Miranda, José Luis; Celis, Lourdes B.; Estévez, Miriam; Chávez, Valeria; van Tussenbroek, Brigitta I.; Uribe-Martínez, Abigail; Cuevas, Eduardo; Rosillo Pantoja, Izarelly; Masia, Luis; Cauich-Kantun, Citlali; Silva, Rodolfo (November 12, 2021). "Commercial Potential of Pelagic Sargassum spp. in Mexico". Frontiers in Marine Science. Frontiers Media SA. 8. doi:10.3389/fmars.2021.768470. ISSN 2296-7745. Material was copied from this source, which is available under a Creative Commons Attribution 4.0 International License Archived October 16, 2017, at the Wayback Machine.
  2. ^ Wang, Mengqiu; Hu, Chuanmin; Barnes, Brian B.; Mitchum, Gary; Lapointe, Brian; Montoya, Joseph P. (July 5, 2019). "The great Atlantic Sargassum belt". Science. 365 (6448): 83–87. Bibcode:2019Sci...365...83W. doi:10.1126/science.aaw7912. ISSN 0036-8075. PMID 31273122. S2CID 195804245. Archived from the original on March 17, 2023. Retrieved March 18, 2023.
  3. ^ Shao, Elena (April 19, 2023). "Those Seaweed Blobs Headed for Florida? See How Big They Are". The New York Times. ISSN 0362-4331. Retrieved April 19, 2023.
  4. ^ Barberton, Zan (March 7, 2023). "The creeping threat of the Great Atlantic Sargassum Belt". The Guardian. ISSN 0261-3077. Archived from the original on March 18, 2023. Retrieved March 18, 2023.
  5. ^ "Outlook of 2023 Sargassum blooms in the Caribbean Sea and Gulf of Mexico" (PDF). University of South Florida. March 1, 2023. Archived (PDF) from the original on March 16, 2023. Retrieved March 18, 2023.
  6. ^ a b Gibbens, Sarah (March 16, 2023). "A giant, rotting mass of seaweed threatens beach season in the U.S." National Geographic. Archived from the original on March 18, 2023. Retrieved March 18, 2023.
  7. ^ Yong, Ed (July 4, 2019). "Why Waves of Seaweed Have Been Smothering Caribbean Beaches". The Atlantic. Archived from the original on March 16, 2023. Retrieved March 18, 2023.
  8. ^ Marchante, Michelle (March 17, 2023). "Miami Beach and the Keys could get loads of seaweed. It's smelly and can cause these symptoms". Miami Herald.
  9. ^ Coto, Dánica (August 3, 2022). "Record amount of seaweed is choking shores in the Caribbean". AP News. Archived from the original on December 10, 2022. Retrieved March 19, 2023.
  10. ^ Luscombe, Richard (June 3, 2023). "Clumps of 5,000-mile seaweed blob bring flesh-eating bacteria to Florida". The Guardian. ISSN 0261-3077. Retrieved June 5, 2023.
  11. ^ Thomson, Jess (May 30, 2023). "Seaweed full of flesh-eating bacteria hitting Florida". Newsweek. Retrieved June 5, 2023.
  12. ^ Schell, Jeffrey; Goodwin, Deborah; Siuda, Amy (September 1, 2015). "Recent Sargassum Inundation Events in the Caribbean: Shipboard Observations Reveal Dominance of a Previously Rare Form". Oceanography. 28 (3): 8–10. doi:10.5670/oceanog.2015.70. ISSN 1042-8275.

External links

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