Sargasso Sea

The Sargasso Sea (/sɑːrˈɡæsoʊ/) is a region of the Atlantic Ocean bounded by four currents forming an ocean gyre.[1] Unlike all other regions called seas, it has no land boundaries.[2][3][4] It is distinguished from other parts of the Atlantic Ocean by its characteristic brown Sargassum seaweed and often calm blue water.[1]

Not to be confused with Saragossa.
For other uses, see Sargasso Sea (disambiguation).

Map of the Sargasso Sea
The Sargasso Sea in the North Atlantic is bounded by the Gulf Stream on the west, the North Atlantic Current on the north, the Canary Current on the east, and the North Equatorial Current on the south.

The sea is bounded on the west by the Gulf Stream, on the north by the North Atlantic Current, on the east by the Canary Current, and on the south by the North Atlantic Equatorial Current, the four together forming a clockwise-circulating system of ocean currents termed the North Atlantic Gyre. It lies between 20° and 35° north and 40° and 70° west and is approximately 1,100 kilometres (600 nautical miles) wide by 3,200 km (1,750 nmi) long. Bermuda is near the western fringes of the sea.

While all of the above currents deposit marine plants and refuse into the sea, ocean water in the Sargasso Sea is distinctive for its deep blue color and exceptional clarity, with underwater visibility of up to 60 m (200 ft).[5] It is also a body of water that has captured the public imagination, and so is seen in a wide variety of literary and artistic works and in popular culture.[6]

History

The first known written account of the Sargasso Sea dates to Christopher Columbus in 1492, who wrote about seaweed that he feared would trap his ship and potentially hide shallow waters that could run them aground, as well as a lack of wind that he feared would trap them.[7]

The sea may have been known to earlier mariners, as a poem by the late fourth century author Avienius describes a portion of the Atlantic as being covered with seaweed and windless, citing a now-lost account by the fifth century BCE Carthaginian Himilco the Navigator. Columbus himself was aware of this account and thought Himilco had reached the Sargasso Sea, as did several other explorers. However, modern scholars consider this unlikely.[8] According to the cartographer Muhammad al-Idrisi, the Mugharrarūn (Arabic: المغررون, "the adventurers") sent by the Almoravid sultan Ali ibn Yusuf (1084–1143), led by his admiral Ahmad ibn Umar, reached a part of the ocean covered by seaweed,[9] identified by some as the Sargasso Sea.[10]

In 1609, the English vessel Sea Venture was blown to the shore of Bermuda. The sea has also been the site of whaling and fishing.[11]

The 1920–1922 Dana expeditions, led by Johannes Schmidt, determined that the European eel's breeding sites were in the Sargasso Sea.[12][13] The sea has played a role in a number of other pioneering research efforts, including William Beebe and Otis Barton's 1932 dive where they conducted observations of animals and radio broadcasts, John Swallow's work on the Swallow float in the late 1950s, the discovery of Prochlorococcus by a team of researchers in the 1980s, and various oceanographic data gathering programs such as those of Henry Stommel.[14]

In July 1969, British businessman and amateur sailor Donald Crowhurst disappeared after his yacht became mired in the Sargasso Sea. He had been competing in the Sunday Times Golden Globe Race, a single-handed, round-the-world yacht race when his poorly-prepared boat began to take on water. He abandoned his circumnavigation attempt, but reported false positions by radio in an attempt to give the impression that he was still participating. Eventually, Crowhurst wound up drifting in the Sargasso Sea, where he deteriorated psychologically, filling his logbooks with metaphysical speculation and delusional comments. His last entry was July 1, and his yacht was found unoccupied and drifting on July 10. It is unclear whether his death came as the result of suicide or misadventure.[15][16]

Boundaries

The sea is bounded on the west by the Gulf Stream, on the north by the North Atlantic Current, on the east by the Canary Current, and on the south by the North Atlantic Equatorial Current, the four together forming a clockwise-circulating system of ocean currents termed the North Atlantic Gyre.[17] It lies between 20° to 35° N and 40° and 70° W and is approximately 1,100 km (600 nmi) wide by 3,200 km (1,750 nmi) long.[18][19] Bermuda is near the western fringes of the sea.[20]

Because the Sargasso Sea is bordered by oceanic currents, its precise borders may change. The Canary Current in particular is widely variable, and often the line utilized is one west of the Mid-Atlantic Ridge. A 2011 report based the sea's boundaries on several variables including currents, presence of seaweed, and the topography of the ocean floor, and determined that the specific boundaries of the sea were "between 22°–38°N, 76°–43°W and centred on 30°N and 60°W" for a total of around 4,163,499 km2 (1,213,882 sq nmi).[21]

Ecology
Lines of sargassum in the Sargasso Sea

The Sargasso Sea is home to seaweed of the genus Sargassum, which floats en masse on the surface.[22] The Great Atlantic Sargassum Belt is the largest such mass in the world.[23] The sargassum masses generally are not a threat to shipping, and historic incidents of sailing ships being trapped there are due to the often calm winds of the horse latitudes.[22]

The Sargasso Sea plays a role in the migration of catadromous eel species such as the European eel, the American eel, and the American conger eel. The larvae of these species hatch within the sea, and as they grow they travel to Europe or the East Coast of North America. Later in life, the matured eel migrates back to the Sargasso Sea to spawn and lay eggs. It is also believed that after hatching, young loggerhead sea turtles use currents such as the Gulf Stream to travel to the Sargasso Sea, where they use the sargassum as cover from predators until they are mature.[24][25] The sargassum fish is a species of frogfish specially adapted to blend in among the sargassum seaweed.[26]

In the early 2000s, the Sargasso Sea was sampled as part of the Global Ocean Sampling survey, to evaluate its diversity of microbial life through metagenomics. Contrary to previous theories, results indicated the area has a wide variety of prokaryotic life.[27]

Though commonly called seaweed, Sargassum is a type of macroalgae. Like all algae, it produces oxygen. Based on 1975 measurements of oxygen production, and estimates of the total mass of Sargassum in the sea, it can be calculated that the Sargasso Sea may produce 2.2 billion Liters of O2 per hour.[28] This makes it a very important part of global ecology.

Threats

Pollution

Owing to surface currents, the Sargasso accumulates a high concentration of non-biodegradable plastic waste.[29][30] The area contains the huge North Atlantic garbage patch.[31]

Several nations and nongovernmental organizations have united to protect the Sargasso Sea.[32] These organizations include the Sargasso Sea Commission[33] established 11 March 2014 by the governments of the Azores (Portugal), Bermuda (United Kingdom), Monaco, the United Kingdom and the United States.

Bacteria that consume plastic have been found in the plastic-polluted waters of the Sargasso Sea; however, it is unknown whether these bacteria ultimately clean up poisons or simply spread them elsewhere in the marine microbial ecosystem. Plastic debris can absorb toxic chemicals from ocean pollution, potentially poisoning anything that eats it.[34]

Others

Human activity in the Sargasso Sea has negatively impacted it, such as over-fishing and shipping.[35]

The Sargasso Sea is often portrayed in literature and the media as an area of mystery.[6] It is often depicted in fiction as a dangerous area where ships are mired in weed for centuries, unable to escape.[36]

Literature

Ezra Pound's Portrait d'une Femme opens with the line: "Your mind and you are our Sargasso Sea", suggesting that the woman addressed in the poem is a repository of trivia and disconnected facts.[37]

The Sargasso Sea features in classic fantasy stories by William Hope Hodgson, such as his novel The Boats of the "Glen Carrig" (1907), Victor Appleton's Don Sturdy novel Don Sturdy in the Port of Lost Ships: Or, Adrift in the Sargasso Sea, and several related short stories.[38] Jules Verne's Twenty Thousand Leagues Under the Seas describes the Sargasso Sea and gives an account of its formation.[39] Thomas Allibone Janvier's 1898 novel is titled In the Sargasso Sea.[40]

Wide Sargasso Sea (1966) by Jean Rhys is a rewriting of Charlotte Brontë's Jane Eyre from Bertha Mason's point of view.[41][42]

Music

References

Notes

  1. Stow, Dorrik A.V. (2004). Encyclopedia of the Oceans. Oxford University Press. p. 90. ISBN 978-0198606871. Retrieved 27 June 2017.
  2. NGS Staff (27 September 2011). "Sea". nationalgeographic.org. National Geographic Society. Retrieved 27 June 2017. ...a sea is a division of the ocean that is enclosed or partly enclosed by land...
  3. Karleskint, George (2009). Introduction to Marine Biology. Boston: Cengage Learning. p. 47. ISBN 978-0495561972. Retrieved 7 January 2017.
  4. "What's the Difference between an Ocean and a Sea?". Ocean Facts. Silver Spring MD: National Ocean Service (NOS), National Oceanic and Atmospheric Administration (NOAA). 25 March 2014. Retrieved 7 January 2017 – via OceanService.NOAA.gov.
  5. "Sargasso Sea". World Book. 1958. Vol. 15. Field Enterprises Educational Corp.
  6. Heller, Ruth (2000). A Sea Within a Sea: Secrets of the Sargasso. Price Stern Sloan. ISBN 978-0448424170.
  7. Sargasso Sea Alliance 2011, p. 10.
  8. Akyeampong, Emmanuel Kwaku; Gates, Henry Louis Jr. (2012). Dictionary of African Biography. OUP. p. 70. ISBN 978-0195382075.
  9. الإدريسي, أبي عبد الله محمد بن محمد/الشريف (2020). نزهة المشتاق في اختراق الآفاق (in Arabic). Dar Al Kotob Al Ilmiyah دار الكتب العلمية. ISBN 978-2745165633.
  10. Fromherz, Allen James, '‘The Near West’', p. 133. 2016, Edinburgh University Press. ISBN 978-1474426404
  11. Sargasso Sea Alliance 2011, p. 11.
  12. "Where Do Eels Come From?". The New Yorker. 14 May 2020. Retrieved 2 October 2021.
  13. Benson, Keith Rodney; Benson, Keith R.; Rehbock, Philip F. (2002). Oceanographic History: The Pacific and Beyond. University of Washington Press. p. 196. ISBN 978-0295982397.
  14. Sargasso Sea Alliance 2011, p. 28.
  15. McCrum, Robert (4 April 2009). "Deep water". The Guardian. Retrieved 30 September 2021.
  16. Proudfoot, Shannon (2016). "Inside Donald Crowhurst's heartbreaking round-the-world hoax". Sportsnet. Retrieved 30 September 2021.
  17. "Ocean Gyre". National Geographic. Retrieved 24 June 2022.
  18. "Sargasso Sea". oceanfdn.org. The Ocean Foundation. 14 September 2015. Retrieved 27 June 2017.
  19. Weatheritt, Les (2000). Your First Atlantic Crossing: A Planning Guide for Passagemakers (4th ed.). London: Adlard Coles Nautical. ISBN 978-1408188088. Retrieved 27 June 2017.
  20. Webster, George (31 May 2011). "Mysterious waters: from the Bermuda Triangle to the Devil's Sea". CNN. Retrieved 27 June 2017.
  21. Sargasso Sea Alliance 2011, p. 7.
  22. "Sargasso". Straight Dope. August 2002.
  23. Wang, Mengqiu; Hu, Chuanmin; Barnes, Brian B.; Mitchum, Gary; Lapointe, Brian; Montoya, Joseph P. (5 July 2019). "The great Atlantic Sargassum belt". Science. 365 (6448): 83–87. doi:10.1126/science.aaw7912. ISSN 0036-8075. PMID 31273122.
  24. "Turtles return home after UK stay". BBC News. 30 June 2008. Retrieved 23 May 2010.
  25. "Satellites track turtle 'lost years'". BBC News. 5 March 2014. Retrieved 5 March 2014.
  26. "In the Sargasso Sea, life depends on floating sargassum seaweed". National Geographic Society. 15 May 2019.
  27. Venter, JC; Remington, K; Heidelberg, JF; et al. (April 2004). "Environmental genome shotgun sequencing of the Sargasso Sea". Science. 304 (5667): 66–74. Bibcode:2004Sci...304...66V. CiteSeerX 10.1.1.124.1840. doi:10.1126/science.1093857. PMID 15001713. S2CID 1454587.
  28. Blake, Norman J.; Johnson, David L. (August 1976). "Oxygen production-consumption of the pelagic Sargassum community in a flow-through system with arsenic additions". Deep Sea Research and Oceanographic Abstracts. 23 (8): 773–778. doi:10.1016/S0011-7471(76)80020-4.
  29. "The Trash Vortex (2008)". Greenpeace. Archived from the original on 11 January 2009. Retrieved 20 April 2008.
  30. "The trash vortex (2014)". Greenpeace.
  31. Wilson, Stiv J. (16 June 2010). "Atlantic Garbage Patch". HuffPost. Retrieved 27 June 2017.
  32. Shaw, David (27 May 2014). "Protecting the Sargasso Sea". Science & Diplomacy. 3 (2).
  33. "Sargasso Sea Commission". sargassoalliance.org. Retrieved 7 January 2017.
  34. Gwyneth Dickey Zaikab (March 2011). "Marine microbes digest plastic". Nature. doi:10.1038/news.2011.191.
  35. Sargasso Sea Alliance 2011, p. 33.
  36. Ryther, John H. (1956). "The Sargasso Sea". Scientific American. 194 (1): 98–108. Bibcode:1956SciAm.194a..98R. doi:10.1038/scientificamerican0156-98. ISSN 0036-8733. JSTOR 24943833.
  37. Roberts, Brian Russell; Stephens, Michelle Ann (2017). Archipelagic American Studies. Duke University Press. ISBN 978-0822373209.
  38. Hodgeson, William Hope (2011). The Collected Fiction of William Hope Hodgson: Boats of Glen Carrig & Other Nautical Adventures. New York: Night Shade Books. ISBN 978-1892389398.
  39. Verne, Jules (1870). 20,000 Leagues Under the Seas. Translated by Butcher, William (2001 ed.). Oxford University Press. ISBN 978-0192828392.
  40. The Literary World: A Monthly Review of Current Literature. S. R. Crocker. 1898. p. 243.
  41. Jolley, Susan Arpajian (2005). "Teaching "Wide Sargasso Sea" in New Jersey". The English Journal. 94 (3): 61–66. doi:10.2307/30046421. ISSN 0013-8274. JSTOR 30046421.
  42. Gilchrist, Jennifer (2012). "Women, Slavery, and the Problem of Freedom in Wide Sargasso Sea". Twentieth Century Literature. 58 (3): 462–494. doi:10.1215/0041462X-2012-4003. ISSN 0041-462X. JSTOR 24246943.
  43. Nastos, M. G. Allmusic Review accessed September 6, 2011
  44. Tony, Caro and John. "Sargasso Sea". AllMusic. Retrieved 5 November 2021.
  45. Taeko Ohnuki. "Sargasso Sea". AllMusic. Retrieved 19 August 2022.
  46. "Pram – Sargasso Sea". AllMusic. Retrieved 5 November 2021.
  47. Modest Mouse – Dashboard (Official Music Video). YouTube
  48. "Carving Desert Canyons". Discogs. Retrieved 1 October 2023.

Bibliography

Look up Sargasso Sea in Wiktionary, the free dictionary.

28°N 66°W

This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.