Algerian Current

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Oceans and seas (main)


March 29, 2010, 12:00 am
May 16, 2011, 4:36 am

The Algerian Current is a sea current that flows eastward along the Algerian coast in the Alboran Sea, which is the western element of the Mediterranean Sea. This current moves as a narrow, easily distinguished current for around 300 kilometres (km) from about 0 to 4 degrees E with a width of less than 30 km, average and maximum velocities of 0.4 and 0.8 metres per second, respectively, and a transport of about 0.5 Sv. This is a continuation of the current associated with the Almeria-Oran Front that is itself a continuation of the flow of Atlantic Ocean water entering through the Gibraltar Strait.

The Algerian Current operates as a surface coastal jet, hugging the North Arfican shoreline relatively closely. Since the current derives from the Atlantic Ocean entering the Strait of Gibraltar, this surface jet is less saline than the Alboran Sea as a whole. The Algerian Current appears to be more crisply defined in the winter season, when the double gyre of the Alboran Gyre weakens.

At the east of the Alboran Sea, there is a hydrodynamic border termed the Almeria-Oran Front. At this point the coastal jet that has originated in the Atlantic and has hugged the North African coast now splits into two currents: (a) the Algerian Current continues to head east along the Algerian coast, and (b) the Septentrional Current flows northeast to effect a cyclonic gyre through the Liguarian Sea, Gulf of Lyon and Catalan Sea.

According to analysis of Valavanis, the Algerian Current is linked to important upwelling processes along the North African Coast. This seems particularly logical since this wind driven current has high kinetic energy and the colder water naturally has a tendency to sink, creating a vertical churning motion.; in addition the vertical salinity differential in the water column would encourage vertical mixing of these waters along the North African coast. In any case the Algerian Current is not only the most dominant circulation feature of the western Mediterranean Sea, but also creates significant nutrient precursors for Epipelagic zoneprimary production

Further Reading

  • R. A. Arnone, D. E.Wiesenburg, and K. D. Saunders. The origin and characteristics of the Algerian Current. J. Geophys. Res., 95:1587–1598, 1990.
  • Matthias Tomczak and J. Stuart Godfrey. 1994. Regional Oceanography: An Introduction. Pergamon.
  • Jos´e Salas, Emilio Garc´?a-Ladona, and Jordi Font. Statistical analysis of the surface circulation in the Algerian Current using Lagrangian buoys. Journal of Marine Systems, 29:69–85, 2001.
  • Peter Saundry. 2011. Seas of the world. Topic ed. C.Michael Hogan, Ed.-in-chief Cutler J.Cleveland. Encyclopedia of Earth
  • Vasilis D. Valavanis. 2008. Essential Fish Habitat Mapping in the Mediterranean (Google eBook) Springer. 300 pages

Citation

Hogan, C. (2011). Algerian Current. Retrieved from http://editors.eol.org/eoearth/wiki/Algerian_Current