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Indian Ocean

Indian Ocean, third largest ocean, c.28,350,000 sq mi (73,427,000 sq km), extending from S Asia to Antarctica and from E Africa to SE Australia; it is c.4,000 mi (6,400 km) wide at the equator. It constitutes about 20% of the world's total ocean area. The Indian Ocean is connected with the Pacific Ocean by passages through the Malay Archipelago and between Australia and Antarctica; and with the Atlantic Ocean by the expanse between Africa and Antarctica and by the Suez Canal. Its chief arms are the Arabian Sea (with the Red Sea, the Gulf of Aden, and the Persian Gulf), the Bay of Bengal, and the Andaman Sea. The continental shelf of the Indian Ocean is narrow. Madagascar and Sri Lanka, the largest islands in the ocean, are structurally parts of the continents as are Socotra, the Andaman Islands, and the Nicobar Islands; the Seychelles and the Kerguelen Islands are exposed tops of submerged ridges. The Laccadives, the Maldives, and the Chagos are low coral islands, and Mauritius and Réunion are high volcanic cones. The floor of the Indian Ocean has an average depth of c.11,000 ft (3,400 m). The Mid-Oceanic Ridge, a broad submarine mountain range extending from Asia to Antarctica, divides the Indian Ocean into three major sections—the African, Antardis, and Australasian. The ridge rises to an average height of c.10,000 ft (3,000 m), and a few peaks emerge as islands. A large rift, an extension of the eastern branch of the Great Rift Valley that runs through the Gulf of Aden, extends along most of its length (see seafloor spreading). The Mid-Oceanic Ridge, along with other submarine ridges, encloses a series of deep-sea basins (abyssal plains). The greatest depth (25,344 ft/7,725 m) is in the Java Trench, S of Java, Indonesia. The Indian Ocean receives the waters of the Zambezi, Tigris-Euphrates, Indus, Ganges-Brahmaputra, and Irrawady rivers. The surface waters of the ocean are generally warm, although close to Antarctica pack ice and icebergs are found. The Indian Ocean has two water circulation systems—a regular counterclockwise southern system (South Equatorial Current, Mozambique Current, West Wind Drift, West Australian Current) and a northern system, the Monsoon Drift, whose currents are directly related to the seasonal shift of monsoon winds. The southwest monsoon draws moisture from the Indian Ocean and drops heavy rainfall on the Indian subcontinent and Southeast Asia.

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"Indian Ocean." The Columbia Encyclopedia, 6th ed.. . Encyclopedia.com. 23 Mar. 2017 <http://www.encyclopedia.com>.

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"Indian Ocean." The Columbia Encyclopedia, 6th ed.. . Retrieved March 23, 2017 from Encyclopedia.com: http://www.encyclopedia.com/reference/encyclopedias-almanacs-transcripts-and-maps/indian-ocean

Indian Ocean

Indian Ocean Third-largest ocean in the world, bounded by Asia (n), Antarctica (s), Africa (w) and Southeast Asia and Australia (e). Known in ancient times as the Erythraean Sea, the Indian Ocean was the first to be extensively navigated. Branches of the ocean include the Arabian Sea, the Bay of Bengal and the Andaman Sea. Its largest islands are Madagascar and Sri Lanka. The average depth is 4000m (13,000ft) although there is a Mid-Oceanic Ridge, extending from Asia to Antarctica; several of its peaks emerge as islands. The deepest part is the Java Trench, reaching 7725m (25,344ft). The climate of the nearby land masses is strongly influenced by the ocean's winds and currents. There are three wind belts: the monsoons, which pick up moisture from the ocean, bringing heavy rainfall to w India and Southeast Asia; the se trade winds; and the prevailing westerly winds, bringing tropical storms. The currents are governed by these winds, the seasonal shift of the monsoon dictating the flow of water n of the Equator. Area: c.73,600,000sq km (28,400,000sq mi).

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Indian Ocean

Indian Ocean One of the world's major oceans, lying between Africa, India, and Australia. It has a surface area of 77 million km2 and an average depth of 3872 m. The ocean receives a great deal of sediment from three of the world's major rivers (the Ganges, the Indus, and the Brahmaputra).

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"Indian Ocean." A Dictionary of Earth Sciences. . Encyclopedia.com. 23 Mar. 2017 <http://www.encyclopedia.com>.

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"Indian Ocean." A Dictionary of Earth Sciences. . Retrieved March 23, 2017 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/indian-ocean

Indian Ocean

Indian Ocean One of the world's major oceans, lying between Africa, India, and Australia. It has a surface area of 77 million km2 and an average depth of 3872 m. The ocean receives a great deal of sediment from three of the world's major rivers (the Ganges, the Indus, and the Brahmaputra).

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"Indian Ocean." A Dictionary of Ecology. . Encyclopedia.com. 23 Mar. 2017 <http://www.encyclopedia.com>.

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"Indian Ocean." A Dictionary of Ecology. . Retrieved March 23, 2017 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/indian-ocean-0