Location: body of water between Africa, Antarctica, Asia, and
Australia
Geographic coordinates: 30 00 S, 80 00 E
Map references: World
Area: total: 73.6 million sq km note: includes Andaman Sea, Arabian Sea, Bay of Bengal, Great Australian Bight, Gulf of Aden, Gulf of Oman, Mozambique Channel, Persian Gulf, Red Sea, Strait of Malacca, and other tributary water bodies
Area-comparative: 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)
Coastline: 66,526 km
Climate: northeast monsoon (December to April), southwest monsoon
(June to October); tropical cyclones occur during May/June and
October/November in the northern Indian Ocean and January/February in
the southern Indian Ocean
Terrain: surface dominated by counterclockwise gyre (broad, circular system of currents) in the southern Indian Ocean; unique reversal of surface currents in the northern Indian Ocean; low atmospheric 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
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