List of drainage basins by area

The list of drainage basins by area identifies areas larger than 400,000 km2 (150,000 sq mi), sorted by area, which drain to oceans, mediterranean seas, rivers, lakes and other waterbodies. It includes drainage basins which do not flow to the ocean (endorheic basins). It includes oceanic sea drainage basins which have hydrologically coherent areas (oceanic seas are set by IHO convention).

The oceans drain approximately 83% of the land in the world. The other 17% – an area larger than the basin of the Arctic Ocean – drains to internal endorheic basins.

Note that there are substantial areas of the world that do not "drain" in the commonly understood sense. In Arctic deserts much of the snowfall sublimates directly into the air and does not melt into flowing water, while in equatorial deserts precipitation may evaporate before joining any substantial water course. However, these areas can still be included in topographically defined basins if one considers the hypothetical flow of water (or ice), and thus nutrients or pollutants, over the surface of the ground (or ice sheet); this is the approach taken here. For example, the Antarctic ice sheet can be divided into basins,[1] and most of Libya is included the Mediterranean Sea basin even though almost no water from the interior actually reaches the sea.

Contents

Basins

Continent color key
Africa Asia Europe North America Australia South America Antarctica
Basin Type Continent Drains to Basin Area
km2		 Basin Area
mi2		 Notes
Atlantic Ocean Ocean multiple n/a 69,800,000 26,900,000 [2]
Arctic Ocean Ocean multiple n/a 23,100,000 8,900,000 [2]
Pacific Ocean Ocean multiple n/a 20,300,000 7,800,000 [2]
Indian Ocean Ocean multiple n/a 19,400,000 7,500,000 [2]
Southern Ocean Ocean Antarctica n/a 14,000,000 5,400,000 [2][3]
(Eurafrican) Mediterranean Sea Mediterranean sea multiple Atlantic Ocean[4] 8,500,000 3,300,000 [2]
American Mediterranean Sea (Gulf of Mexico and Caribbean Sea) Mediterranean sea multiple Atlantic Ocean[4] 6,200,000 2,400,000 [2]
Amazon River Primary River South America Atlantic Ocean 6,144,727 2,372,492
Río de la Plata Primary River South America Atlantic Ocean 4,144,000 1,600,000 [5]
Congo River Primary River Africa Atlantic Ocean 3,730,474 1,440,344
Caspian Sea Lake Asia/Europe n/a (endorheic basin) 3,626,000 1,400,000
Nile River Primary River Africa Mediterranean Sea 3,254,555 1,256,591
Mississippi-Missouri River Primary River North America Gulf of Mexico 3,202,230 1 236 388 [6]
Ob River Primary River Asia Arctic Ocean 2,972,497 1,147,688
Paraná River Primary River South America Atlantic Ocean 2,582,672 997,175
Yenisei River Primary River Asia Arctic Ocean 2,554,482 986,291
Lake Chad Lake Africa n/a (endorheic basin) 2,497,918 964,452
Black Sea Mediterranean sea multiple Mediterranean Sea[4] 2,400,000 930,000 [2]
Lena River Primary River Asia Arctic Ocean 2,306,772 890,650
Niger River Primary River Africa Atlantic Ocean 2,261,763 873,272
Amur River Primary River Asia Pacific Ocean 1,929,981 745,170
Mackenzie River Primary River North America Arctic Ocean 1,743,058 672,998
Yangtze River (Chang Jiang) Primary River Asia Pacific Ocean 1,722,155 664,927
Baltic Sea Mediterranean sea Europe Atlantic Ocean[4] 1,700,000 660,000 [2]
Irtysh River Tributary River Asia Ob River 1,673,470 646,130
Ganges–Brahmaputra Primary River Asia Bay of Bengal 1,621,000 626,000 [7]
Aral Sea Lake Asia n/a (endorheic basin) 1,618,750 625,000
Madeira River Tributary River South America Amazon River 1,485,218 573,446
Volga River Primary River Europe Caspian Sea 1,410,994 544,788
Persian Gulf Mediterranean sea Asia Indian Ocean[4] 1,400,000 540,000 [2]
Zambezi River Primary River Africa Indian Ocean 1,332,574 514,510
Missouri River Tributary River North America Mississippi River 1,331,810 514,215 [6]
Paraguay River Tributary River South America Paraná River 1,168,540 451,176
Lake Eyre Basin Lake Australia n/a (endorheic basin) 1,200,000 460,000 [8]
Tarim Basin endorheic basin Asia n/a (endorheic basin) 906,500 350,000 [9]
Australasian Mediterranean Sea Mediterranean sea multiple Pacific / Indian Oceans[4] 1,100,000 420,000 [2]
Nelson River Primary River North America Hudson Bay 1,093,442 422,180
Indus River Primary River Asia Indian Ocean 1,081,733 417,659
Murray-Darling basin Primary River Australia Southern Ocean 1,072,000 413,900
St. Lawrence River Primary River North America Atlantic Ocean 1,049,621 405,261
Ganges River Primary River Asia Indian Ocean 1,016,104 392,320
Great Slave Lake Lake North America Mackenzie River 976,200 376,913
Orinoco River Primary River South America Atlantic Ocean 953,598 368,186
Huang He (Yellow River) Primary River Asia Pacific Ocean 945,065 364,892
Orange River Primary River Africa Atlantic Ocean 941,421 363,485
Kasai River Tributary River Africa Congo River 925,172 357,211
Yukon River Primary River North America Bering Sea 847,642 327,276
Mekong River Primary River Asia Pacific Ocean 805,627 311,054
Great Lakes Lake North America St. Lawrence River 800,114 308,926
Danube River Primary River Europe Black Sea 795,686 307,216
Syr Darya Primary River Asia Aral Sea 782,669 302,190
Tigris-Euphrates Rivers Primary River Asia Persian Gulf 765,831 295,689
Tocantins River Primary River South America Atlantic Ocean 764,183 295,053
Okavango River/Okavango Delta Primary River Africa n/a (endorheic basin) 721,277 278,487
Rio Negro Tributary River South America Amazon River 720,114 278,038
Colorado River (U.S.) Primary River North America Gulf of California 703,132 271,481
Kolyma River Primary River Asia Arctic Ocean 679,908 262,514
Columbia River Primary River North America Pacific Ocean 657,490 253,858
Brahmaputra River Primary River Asia Indian Ocean 651,334 251,481
Red Sea Mediterranean sea multiple Indian Ocean[4] 620,000 230,000 [2]
São Francisco River Primary River South America Atlantic Ocean 617,812 238,539
Ubangi River Tributary River Africa Congo River 613,202 236,759
Rio Grande Primary River North America Gulf of Mexico 608,023 234,759
Lake Baikal Lake Asia Angara River 571,000 220,000
Chari River Primary River Africa Lake Chad 548,747 211,872
Amu Darya Primary River Asia Aral Sea 534,764 206,474
Dnieper River Primary River Europe Black Sea 531,817 205,336
Xingu River Tributary River South America Amazon River 520,292 200,886
Lake Balkhash Lake Asia n/a (endorheic basin) 512,010 197,688
Viljuj River Tributary River Asia Lena River 507,874 196,091
Kama River Tributary River Europe Volga River 507,000 195,754
Jubba River Primary River Africa Indian Ocean 497,655 192,146
Great Basin   North America n/a (endorheic basin) 492,000 190,000 [10]
Ohio River Tributary River North America Mississippi River 490,603 189,423
Tapajos River Tributary River South America Amazon River 486,792 187,951
Songhua River Tributary River Asia Amur River 459,745 177,509
Don River Primary River Europe Black Sea 458,703 177,106
Arkansas River Tributary River North America Mississippi River 435,122 168,002
Saskatchewan River Tributary River North America Lake Winnipeg 435,000 168,000
Tobol River Tributary River Asia Irtysh River 426,000 164,480
Limpopo River Primary River Africa Indian Ocean 421,168 162,614
Senegal River Primary River Africa Atlantic Ocean 419,659 162,031
Ayeyarwady River Primary River Asia Indian Ocean 413,674 159,720
Pearl River Primary River Asia Pacific Ocean 409,458 158,093
Volta River Primary River Africa Atlantic Ocean 407,093 157,179
Colorado River (Argentina) Primary River South America Atlantic Ocean 402,956 155,582
Rhine Primary river Europe North Sea 170,000 65,637
Meuse Primary river Europe North Sea 36,000 13,900
Scheldt Primary river Europe North Sea 21,860 8,440
Elbe Primary river Europe North Sea 148,268 57,247
Weser Primary river Europe North Sea 46,300 17,900
Apalachicola-Chattahoochee-Flint Primary River North America Gulf of Mexico 53,072 20,500

See also

Notes

  1. ^ [1]
  2. ^ a b c d e f g h i j k l This is an approximate value based on geospatial data from the USGS.[2] Approximate values for the area of Greenland and Antarctica were added to this data.
  3. ^ The value listed here assumes that the entire continent drains to the ocean, such as through the many ice streams, outlet glaciers, and seasonal glacial streams along the coast. However, there are many small endorheic lakes, for example in the McMurdo Dry Valleys.
  4. ^ a b c d e f g Note that the connection between a mediterranean sea (or a large estuary) and its parent ocean usually involves simultaneous inflow and outflow in the lower and upper water layers of the connecting channel. Depending on the salinity of the sea, the upper layer may either flow into or out from the ocean; the bottom layer will flow the opposite direction.
  5. ^ "Río de la Plata". Encyclopædia Britannica. http://www.britannica.com/EBchecked/topic/463804/Rio-de-la-Plata. Retrieved 21 May 2011. 
  6. ^ a b The Mississippi is not the longest watercourse in the Mississippi-Missouri watershed; the combination of the Lower Mississippi and the Missouri is longer. The Upper Mississippi River could thus be seen as a tributary of that river. See list of rivers by length for more details.
  7. ^ Arnold, Guy (2000). World strategic highways. Taylor & Francis. p. 223. ISBN 9781579580988. http://books.google.com/books?id=FarwCNdYdmoC&pg=PA223. Retrieved 17 May 2011. 
  8. ^ "Map of the Lake Eyre basin". Environment.gov.au. 2011-02-18. http://www.environment.gov.au/water/environmental/rivers/leb.html. Retrieved 2011-04-10. 
  9. ^ "Encyclopædia Britannica". Britannica.com. http://www.britannica.com/EBchecked/topic/583570/Tarim-Basin. Retrieved 2011-04-10. 
  10. ^ "Boundary Descriptions and Names of Regions, Subregions, Accounting Units and Cataloging Units". USGS.gov. http://water.usgs.gov/GIS/huc_name.html. Retrieved 2010-12-21.  NOTE: The Great Basin is a set of endorheic drainage basins, the largest being the 35,910 km2 (13,860 sq mi) that drains into the Great Salt Lake.

External links