1990 Edition
CIA World Factbook 1990 (Project Gutenberg)
Geography
Climate
northeast monsoon (December to April), southwest monsoon (June to October); tropical cyclones occur during May/June and October/November in the north Indian Ocean and January/February in the south Indian Ocean
Coastline
66,526 km
Comparative area
slightly less than eight times the size of the US; third-largest ocean (after the Pacific Ocean and Atlantic Ocean, but larger than the Arctic Ocean)
Environment
endangered marine species include the dugong, seals, turtles, and whales; oil pollution in the Arabian Sea, Persian Gulf, and Red Sea
Natural resources
oil and gas fields, fish, shrimp, sand and gravel aggregates, placer deposits, polymetallic nodules
Note
major choke points include Bab el Mandeb, Strait of Hormuz, Strait of Malacca, southern access to the Suez Canal, and the Lombok Strait; ships subject to superstructure icing in extreme south near Antarctica from May to October
Terrain
surface dominated by counterclockwise gyre (broad, circular system of currents) in the south Indian Ocean; unique reversal of surface currents in the north Indian Ocean--low pressure over southwest Asia from hot, rising, summer air results in the southwest monsoon and southwest-to-northeast winds and currents, while high pressure over northern Asia from cold, falling, winter air results in the northeast monsoon and northeast-to-southwest winds and currents; ocean floor is dominated by the Mid-Indian Ocean Ridge and subdivided by the Southeast Indian Ocean Ridge, Southwest Indian Ocean Ridge, and Ninety East Ridge; maximum depth is 7,258 meters in the Java Trench
Total area
73,600,000 km2; Arabian Sea, Bass Strait, Bay of Bengal, Java Sea, Persian Gulf, Red Sea, Strait of Malacca, Timor Sea, and other tributary water bodies
Economy
Industries
based on exploitation of natural resources, particularly marine life, minerals, oil and gas production, fishing, sand and gravel aggregates, placer deposits
Overview
The Indian Ocean provides a major transportation highway for the movement of petroleum products from the Middle East to Europe and North and South American countries. Fish from the ocean are of growing economic importance to many of the bordering countries as a source of both food and exports. Fishing fleets from the USSR, Japan, Korea, and Taiwan also exploit the Indian Ocean for mostly shrimp and tuna. Large reserves of hydrocarbons are being tapped in the offshore areas of Saudi Arabia, Iran, India, and Western Australia. An estimated 40% of the world's offshore oil production comes from the 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.
Communications
Ports
Bombay (India), Calcutta (India), Madras (India), Colombo (Sri Lanka), Durban (South Africa), Fremantle (Australia), Jakarta (Indonesia), Melbourne (Australia), Richard's Bay (South Africa)
Telecommunications
no submarine cables