HARALD ULRIK SVERDRUP (1888-1957)
Harald Sverdrup was a Norwegian oceanographer, meteorologist and arctic explorer. He is widely recognized as the founder of the modern school of physical oceanography; was the chief scientist on Amundsen’s 1918-25 Arctic Expedition; and was the first head of the Norwegian Polar Institute.
Early Life and Arctic Exploration
Sverdrup was born on November 15, 1888, in Sogndal, Sogn, Norway. At university, he intended to major in Physical Geography and Astronomy, but he became more and more interested in meteorology and oceanography and switched majors.
From 1918 to 1925 he joined the North Polar expedition of Roald Amundsen, as chief scientist aboard the Maud. His measurements of bottom depths, tidal currents, and tidal elevations on the vast shelf areas off the East Siberian Sea correctly described the propagation of tides as Poincare waves. In 1926 he was offered the chair of meteorology at the University of Bergen in Norway, where he worked on the data collected on the Maud expedition and edited the expeditions’ scientific report.
A leader in Oceanography
In 1936 Sverdrup was made director of California’s Scripps Institution of Oceanography (SIO). Under his direction SIO became the first, and for a long time the only, American institution that offered graduate instruction in oceanography. Sverdrup produced a detailed oceanographic dataset off the coast of California and developed a simple theory of the general ocean circulation, postulating a dynamical vorticity balance between the wind-stress curl and the meridional gradient of the Coriolis parameter, the Sverdrup balance. He, along with Martin W. Johnson and Richard H. Fleming, also published The Oceans: Their Physics, Chemistry and General Biology, which formed the basic curriculum of oceanography for the next 40 years around the world.
The Norwegian-British-Swedish Expedition
Sverdrup returned to Norway in 1948, where he continued to contribute to oceanography, ocean biology and polar research. He organized and became director of the Norwegian Polar Institute and was instrumental in organizing the Norwegian-British-Swedish Expedition (NBSX) of 1949-52. This was the first Antarctic expedition involving an international team of scientists and the expedition’s work generated several significant ideas:
- Glaciology: the proposition that world sea-level was principally controlled by the state of the Antarctic ice-sheet.
- Meteorology: an improved understanding was developed of the importance of the Antarctic ice-sheets in regulating the world’s climate.
- Geology: based on the geological findings it was suggested that Dronning Maud Land was once joined to Southern Africa.
- Organization: NBSX paved the way for international co-operation in manning and running Antarctic expeditions during the International Geophysical Year of 1957-58.
Sverdrup was a member of the American and Norwegian Academies of Science and the Swedish Order of the Polar Star. The sverdrup (Sv) is used in physical oceanography as an abbreviation for a volume flux of one million cubic meters per second. The American Meteorological Society named the Sverdrup Gold Medal Award in his honor as well. This award recognizes researchers for outstanding contributions to the scientific knowledge of interactions between the oceans and the atmosphere.