ZUBOV, NIKOLAY NIKOLAEVICH

(b. Izmail, Russia [now Ukrainian S. S. R.], 23 May 1885;d. Moscow, U.S.S.R., 11 November 1960)

ocean ography.

The son an officer, Zubov followed family tradition adn enrolled in the Naval cadet Corps, from which he graduated in 1904. He then attended the Naval Academy, where his interest tured to hydrography. After graduating in 1910, Zubov served as navigator and commander of a torpedoboat. In 1912, on a cruise in the Barents Sea aboard the messenger ship Barkan Zubov carried out his first scientific work, a plane-table and hydrographic survey of Matyushikha Inlet, on Novaya Zemlya, and of the lower course and mouth of the pesha River, at the Cheshska Gulf. The following year he entered civil service as hydrographer in the office of commercial ports of the Ministry of trade and Industry. Soon afterward he participated in the scientific expedition to the Baltic Sea opf the schooner Utro, and in 1914 he was sent to Norway to continue his education at the geophysics institute at Bergen.

World War I interrupted Subov’s studies and he returned to military service as commander of the torpedo boat Burny; after the war he served at naval headquarters. Zubov was one of the first members of the Floating Marine Scientific Institute (later the State Institute of Oceanography). founded in 1921 to study the Soviet Union’s northern seas; he was also dsirectosr of the hydrological section. In 1923 the institutue acquured its own expedition ship, the persia which, with Zubov’s participation completed four hydrographic sections of the southwest Barents sea by 1928 using only modest equipment (two bahometers, each kcontaining a thermometer, and two rotors). Zubov presented his scientjific conclusions in a series of articles (1929-1932); that were later generlaized in a fundamesntal memoir (1932); this work deals with the three major problems that retained his interest throughout his life; the vertical mixing of seawater, ocean currents, and sea ice.

Zubov explained the origin of intermediate layers of warm and cold seawater and gave a theoretical basis and practical method for estimating the intensity of the vertical circulation during the winter. His findings were immediately applied to explain the degree of aeration of deep-sea layers, data needed in estimating fish reserves and their food resources. His subsequently elaborated concept of the index of freezing was important in compiling forecasts of sea ice.

Zubov also reexamined and reinterpreted the theoredtical basis of Whilhelm Bjerknes’ indirect method of determining the elemesnts of ocean currents. whereas Bjerknes believed the heterogeneity of densjsity to be the cause of currents. Zubov considered it, to a much greater extent, a consequence of them. Zubov demonstrated that Bjerknes’ method failed to reckon fully with density currents of any origin. Zubov called his method of calculating currents according to the distribution of density the “dynamic method of processing oceanologic observations.” His practical handbook on the subject (1935) led to a series of “dynamic maps” of the soviet Unions’s northern seas that gave the first sufficient accurate picture of their currents.

In his 1932 memor Zubov also included his theory of climatic changes of currents, described their influence on sea ice, and gave the basis for forecasting ice in the polar seas. Internal waves and high tides were also considerd; the latter subject was also dealt with in an important monograph (1933) that includes a rigorous exposition of the modern theory of high tides.

As secretary of the Soviet committee of the second international Ploar Year (1932-1933), Zubov was responsible for introducing into the program Soviet studsies of the Arctic Ocean and of its northern seas, from the Greenland to the Chukchi seas, as well as the bering and Okhotsk seas and the Seas of Japan. During the summer of 1932 he participated in a cruise aboard the small sail-and-motor-powered trawler, the N.M. Knipovich The excursion confsirmed the accuracy of Zubov’s forecast that ice condkitions would be extremely light in the Barents Sea, even at the highest latitudes; and the Knipovich-although completely unifit for high-latitude navigation-attained the latitude of 82˚05′ and was the first ship ever to circumnavigate franz Joseph Land.

In 1935 Zubov headed the scientific section of the first Soviet high-latitude expedition of the icebraker Sadko, which explored the upper latitudes of the Greenland, Barents, and Kara seas, and charted the paths of the deep northern currents that penetrate the warm waters of the Atlantic in the Kara Sea.

He also engaged in aerial reconnaissance of Arcticice, proposing early spring surveys of separate regions and reconnaissance of an entire route “with only the naked eye.” He completed his last flight over the Arctiv practically on the eve of his seventieth birthday. Like the others it yielded new information used to maintain navigation through the northern sea routes.

Having returned to naval service at the beginning of World War II, Zubov was sent to Arkhan gelsk, charged with maintaining an open passage through the ice at the mouth of the Northern Dvina River for the White Sea military flotilla. In an original work on the subject (1942) Zubov started from the assumption that in certain cases ice may be considered not as an elastic, but as a plastic, body. his formula based on this proposition for determining the flexure of ice under a given load was subsequently confirmed in practice. In his important monograph on Archtic ice (1945) Zubov presented the laws of the origin, growth, movement and hummocking, weakening, and melting of the Arcticice cover. Central to the work is his conception of the unity of the “air-ice-water” system, of the close interdependence of phenomena in these areas, and of the continually changing condition of the ice. Of special importance to navigation were his method for predicting the depth of ice, his rule correlating the drift of ice with isobars, and his method of calculating the winter vertical circulation of water and the index of freezing. Certain conclusions that were not based on direct observation at the time they were formulated have subsequently been fully confirmed. For example, begining with his general laws of ice drift, Zubov determined the presence, in that sector of the central polar basin bordering the Pacific Ocean,of an anticyclonic system of ice drift along a gigantic and, in some instances, closed curve. The presence of this circular motion was established over a decade later by the drifting of Soviet and American stations at the North Pole.

Zubov harbored a lifelong dislike of the term “oceanography,” considering it equivalent only to a descriptive study of the sea. He considered himself an “oceanologist,” who attempted to penetrate the very essence of the processes that he studied. In 1931 he created the world’s first department of oceanology at the Hydrometeorological Center of the U.S.S.R. From 1949 to 1960 he was professor of oceanology at the University of Moscow.

Zubov’s abiding concern with observation was expressed in his more than 200 publications. In September 1959, a year before his death, the results of his last two studies were presented to the First International Oceanographic Congress in New York. They dealt with the relation between barometric relief and sea level, and condensation as a result of the intermingling of seawater (written with K.D.Sabinin).

BIBLIOGRAPHY

I. Original Works. An edition of Zubov’s selected works on oceanology was published on his seventieth birthday as Izbrannye trudy po okeanologii (Moscow, 1955). His earlier writings include “Gidrologischeskie raboty Plavuchevo morskogo nauchnogo instituta v yugo-zapadnoy chasti Barentseva morya letom 1928 g. na e/s Persey” (“Hydrological Work of the Floating Marine Scientific Institute in the Southwest Part of the Barents Sea in the Summer of 1928 Aboard the Expedition Ship Persia”), in Trudy Gosudarstvennogo okeanograficheskogo instituta,2 no. 4 (1932); Elementarnoe uchenie o prilivakh v more (“An Elementary Study of High Tides” ; Moscow, 1933); Okeanograficheskie tablitsy (“Oceanographic Tables” Moscow, 1931), based on Kundsen’s Hydrographische Tabellen; 2nd ed., enl., as Okeanologicheskie tablitsy (“Oceanographic Tables” 1940), with supplementary Okeanologicheskie grafiky (“Oceanologic Graphs” 1941), written with K.M.Sirotov; 3rd ed., rev. and enl. (Moscow-Leningrad, 1957); Dinamichesky metod obrabotki okeanologicheskikh nablyudeny (“The Dynamic Method of Processing Oceanologic Observations”; Moscow, 1935); Morkie vody i ldy (“Seawater and Sea Ice” Moscow, 1938); Morya zsemnogo shara (“Seas of the Terrestrial Globe”), appendix to the index of geographic names in the Great Soviet World Atlas (Moscow, 1940), written with A. V. Everling; Ldy Arktiki (“Arctic Ice“; Moscow-Leningrad, 1945); also in English trans.(San Diego, Calif., n.d. [1963]); Dinamicheskaya okeanologia (“Dynamic Oceanology” ; Moscow-Leningrad, 1947); V tsentre Arktiki (“In the Middle of the Arctic” ; Moscow-Leningrad, 1948); Otechestvennye moreplavateliissledovateli morey i okeanov (“Native Navigator-Investigators of the Seas and Oceans” Moscow, 1954); Dinamichesky metod vychislenia elementov morskikh techeny (“dynamic Method of Calculating the Elements of Ocean Currents” Leningrad, 1956); Osnovy uchenia o prolivakh Mirovogo okeana (“Basic Study of Straits of the World’s Oceans” Moscow, 1956); Uplotnenie pri smeshenii morskikh vod raznoy temperatury i solenosti (“Condensation as a Result of Mixing Seawater of Different Temperatures and Salinity” Leingrad, 1957).

II. Secondary Literature. On Zubov and his work, see A. D. Dobrovolsky, “N. N. Zubov-Okeanolog” (“N N. Zubov-Oceanologist”), in Zubov’s lzbrannye trudy (see above), 5-11; and “N. N. Zubov-odin iz krupneyshikh sovetskikh okeanologov “(…One opf the Most Outstanding Soviet Oceanologists”), in Okeanologia,1 no. 2 (1961), 355-359; and B. L. Lagutin, A. M. Muromtsev, and A. A. Yushchak, “Pamyati Nikolaya Nikolaevicha Zubova” (“In Memory of…”), in Meteorologia i gidrologia (1961), no. 5. 59-60.

A. F. Plakhotnik