Endorheic basin

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An endorheic basin, also called an internal drainage system, is a drainage basin, or watershed, that does not flow to one of the Earth's major oceans. This is unlike normal basins that collect in rivers and flow to the ocean. Endorheic basins usually end in a saline lake or a salt flat. They can be found in all parts of the world, but usually in desert locations.[1]

List of major endorheic basins[change | change source]

Major endorheic basins of the world. Basins are shown in dark gray; major endorheic lakes are shown in black.

Antarctica[change | change source]

Endorheic lakes in Antarctica are located in the McMurdo Dry Valleys, Victoria Land, Antarctica, the largest ice-free area in Antarctica.

  • Don Juan Pond in Wright Valley is fed by groundwater from a rock glacier and remains unfrozen throughout the year.
  • Lake Vanda in Wright Valley has a perennial ice cover, the edges of which melt in the summer allowing flow from the longest river in Antarctica, the Onyx River. The lake is over 70 m deep and is hypersaline.
  • Lake Bonney is in Taylor Valley and has a perennial ice over and two lobes separated by the Bonney Riegel. The lake is fed by glacial melt and discharge from Blood Falls. Its unique glacial history has resulted in a hypersaline brine in the bottom waters and fresh water at the surface.
  • Lake Hoare, in Taylor Valley, is the freshest of the Dry Valley lakes receiving its melt almost exclusively from the Canada Glacier. The lake has an ice cover and forms a moat during the Austral summer.
  • Lake Fryxell, in adjacent to the Ross Sea in Taylor Valley. The lake has an ice cover and receives its water from numerous glacial meltwater streams for approximately 6 weeks out of the year. Its salinity increases with depth.

Asia[change | change source]

Caspian Sea, a giant inland basin

Much of western and Central Asia is a single, giant inland basin. It contains several lakes, including:

Australia[change | change source]

Australia, being very dry and having exceedingly low runoff ratios due to its ancient soils, has a great prominence of variable, endorheic drainages. The most important are:

A false-colour satellite photo of Australia’s Lake Eyre
Image credit: NASA’s Earth Observatory

Africa[change | change source]

North and Central America[change | change source]

Great Salt Lake, Satellite photo (2003) after five years of drought

Many small lakes and ponds in North Dakota and Manitoba are endorheic; some of them have salt encrustations along their shores.

Europe[change | change source]

All these lakes are drained, however, either through manmade canals or via karstic phenomena. Minor additional endorheic lakes exist throughout the Mediterranean countries Spain (e.g. Laguna de Gallocanta), Italy, Cyprus (Larnaca and Akrotiri salt lakes) and Greece.

South America[change | change source]

MODIS image from November 4, 2001 showing Lake Titicaca, the Salar de Uyuni, and the Salar de Coipasa. These are all parts of the Altiplano

Ancient[change | change source]

Some of the Earth’s ancient endorheic systems include:

References[change | change source]