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Indian Ocean
Map of Indian Ocean
Introduction Indian Ocean
Indian Ocean is third largest of world's five oceans (after Pacific Ocean and Atlantic Ocean, but larger than Southern Ocean and Arctic Ocean). Four critically important access waterways are Suez Canal (Egypt), Bab el Mandeb (Djibouti-Yemen), Strait of Hormuz (Iran-Oman), and Strait of Malacca (Indonesia-Malaysia).
Geography Indian Ocean
body of water between Africa, Southern Ocean, Asia, and Australia
Geographic coordinates:
20 00 S, 80 00 E
Map references:
Political Map of World
total: 68.556 million sq km
note: includes Andaman Sea, Arabian Sea, Bay of Bengal, Flores Sea, Great Australian Bight, Gulf of Aden, Gulf of Oman, Java Sea, Mozambique Channel, Persian Gulf, Red Sea, Savu Sea, Strait of Malacca, Timor Sea, and other tributary water bodies
Area - comparative:
about 5.5 times size of US
66,526 km
northeast monsoon (December to April), southwest monsoon (June to October); tropical cyclones occur during May/June and October/November in northern Indian Ocean and January/February in southern Indian Ocean
surface dominated by counterclockwise gyre (broad, circular system of currents) in southern Indian Ocean; unique reversal of surface currents in northern Indian Ocean; low atmospheric pressure over southwest Asia from hot, rising, summer air results in southwest monsoon and southwest-to-northeast winds and currents, while high pressure over northern Asia from cold, falling, winter air results in northeast monsoon and northeast-to-southwest winds and currents; ocean floor is dominated by Mid-Indian Ocean Ridge and subdivided by Southeast Indian Ocean Ridge, Southwest Indian Ocean Ridge, and Ninetyeast Ridge
Elevation extremes:
lowest point: Java Trench -7,258 m
highest point: sea level 0 m
Natural resources:
oil and gas fields, fish, shrimp, sand and gravel aggregates, placer deposits, polymetallic nodules
Natural hazards:
occasional icebergs pose navigational hazard in southern reaches
Environment - current issues:
endangered marine species include dugong, seals, turtles, and whales; oil pollution in Arabian Sea, Persian Gulf, and Red Sea
Geography - note:
major chokepoints include Bab el Mandeb, Strait of Hormuz, Strait of Malacca, southern access to Suez Canal, and Lombok Strait

Economy Indian Ocean
Economy - overview:
Indian Ocean provides major sea routes connecting Middle East, Africa, and East Asia with Europe and Americas. It carries a particularly heavy traffic of petroleum and petroleum products from oilfields of Persian Gulf and Indonesia. Its fish are of great and growing importance to bordering countries for domestic consumption and export. Fishing fleets from Russia, Japan, South Korea, and Taiwan also exploit Indian Ocean, mainly for shrimp and tuna. Large reserves of hydrocarbons are being tapped in offshore areas of Saudi Arabia, Iran, India, and western Australia. An estimated 40% of world's offshore oil production comes from Indian Ocean. Beach sands rich in heavy minerals and offshore placer deposits are actively exploited by bordering countries, particularly India, South Africa, Indonesia, Sri Lanka, and Thailand.

Transportation Indian Ocean
Ports and harbors:
Chennai (Madras; India), Colombo (Sri Lanka), Durban (South Africa), Jakarta (Indonesia), Kolkata (Calcutta; India) Melbourne (Australia), Mumbai (Bombay; India), Richards Bay (South Africa)

Transnational Issues Indian Ocean
Disputes - international:
some maritime disputes (see littoral states)