Area - comparative: about 5.5 times the size of the US
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 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 the dugong, seals, turtles, and whales; oil pollution in the Arabian Sea, Persian Gulf, and Red Sea
Geography - note: major chokepoints include Bab el Mandeb, Strait of Hormuz, Strait of Malacca, southern access to the Suez Canal, and the Lombok Strait