oceanography, study of the seas and oceans. The major divisions of oceanography include the geological study of the ocean floor (see plate tectonics) and features; physical oceanography, which is concerned with the physical attributes of the ocean water, such as currents and temperature; chemical oceanography, which focuses on the chemistry of ocean waters; marine biology, the study of the oceanic flora and fauna; and, in meteorology, the interaction between the atmosphere and the ocean.

Oceanography as a comprehensive study dates from the Challenger expedition (1872-76), directed by the naturalists C. W. Thomson, a Scot, and John Murray, a Canadian. The term oceanography became current through reports of the expedition edited by Murray, who later became a leader in the study of ocean sediment. The success of the Challenger expedition and the importance of ocean knowledge to shipping, fisheries, the laying of telegraph cables, and climatological studies led many nations to send out expeditions.

Universities and private individuals, as well as governments, have established institutions for the study of the ocean; there exist today about 250 such institutions. One of the earliest was the marine biological station at Naples (founded 1872), which stimulated the founding of many other seaside stations, some of which, e.g., the Scripps Institution of Oceanography at La Jolla, Calif., have enlarged their activities to include all fields of oceanographic research. Other notable institutions in the field include the Oceanographic Museum at Monaco (1910); the biological station of the Univ. of Oslo; the Woods Hole Oceanographic Institution at Woods Hole, Mass. (1930); and the Lamont-Doherty Geological Observatory of Columbia Univ (1949).

The first international oceanographic organization was the International Council for the Exploration of the Sea (1901). In 1966 the U.S. Congress created the National Council for Marine Resources and Engineering Development charged with exploring all aspects of ocean development, and authorized the National Science Foundation to sponsor sea-grant colleges analogous to the Dept. of Agriculture's sponsorship of land-grant colleges. Projects such as Conshelf, under Jacques Cousteau; Sealab, under the U.S. Navy; Tektite, a cooperative venture of the U.S. Dept. of the Interior and the National Aeronautics and Space Administration; Aquarius under the National Oceanic and Atmospheric Administration; and others have established temporary stations in oceans to see whether humans can live and work underwater for extended periods.

Modern deep-diving equipment has been improved to permit descents to very great depths, such as the U.S. bathyscaphe, Trieste II, which descended to 35,798 ft (10,294 m) in the Marianas Trench in 1960. Smaller, remote-controlled craft, such as the Jason, which was used to examine the sunken steamship Titanic, explore natural and humanmade underwater structures. Deep-diving craft (see submersible) provide invaluable direct observations of the deep ocean bottom, mid-ocean ridges, and marine life. Recent oceanographic studies include drilling of the seafloor (see Deep Sea Drilling Project).

Scripps Institution of Oceanography: see California, Univ. of.

Scientific discipline concerned with all aspects of the world's oceans and seas, including their physical and chemical properties, origin and geology, and life forms. Research entails sampling seawater and marine life, remote sensing of oceanic processes with aircraft and satellites, and exploration of the seafloor. Oceanography aids in predicting weather and climate, in exploitation of the Earth's resources, and in understanding the effects of pollutants. Seealso marine geology.

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or geologic oceanography

Scientific discipline concerned with all geologic aspects of the continental shelves and slopes and the ocean basins. Marine geology originally focused on marine sedimentation and the interpretation of bottom samples. The advent of the concept of seafloor spreading, however, broadened its scope. Many investigations of the oceanic ridge system, the magnetism of rocks on the seafloor, geochemical analyses of deep brine pools, and seafloor spreading and continental drift may be considered within the general realm of marine geology.

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