Shtokman, Vladimir Borisovich

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SHTOKMAN, VLADIMIR BORISOVICH

(b. Moscow, Russia, 10 March l909; d. Moscow, 14 June 1968)

earth science, oceanography.

In 1928 Shtokman entered the Faculty of Physics and Mathematics of Moscow University and chose to specialize in the geophysics of the earth’s hydrosphere. The death of his parents in 1930 and his own illness in 1931 obliged him to interrupt his studies, and he began work as a laboratory assistant at the Institute of Oceanography in Moscow. By 1932 he had become a junior staff member as a result of his first independent scientific work, an investigation of the form of the curved underwater section of a cable carrying oceanographic insruments. He was promoted to senior staff member the following year, after having planned and led an oceanographic year, after having planned and led an oceanographic expedition in Motovskiy Gulf of the Barents Sea that yielded important results.

In 1934 Shtokman was sent to the Azerbaydzhan branch of the All-Union Scientific Research Institute of Ocean Fisheries and Oceanography (VNIRO) at Baku, where he organized and directed a laboratory of physical oceanography.

By applying probability theory and random functions to the study of ocean turbulence, Shtokman was a pioneer in introducing new statistical ideas and methods of studying this phenomenon into the U.S.S.R. He also developed direct techniques of measuring turbulent. pulsation and current velocity at a series of points. These investigations were carried out in the central and southern Caspian Sea during a series of oceanographic expeditions, the majority of which Shtokman led personally. As a result he derived completely new results for turbulent pulsations in the horizontal velocity of marine currents. He also was the first to obtain the coefficients. He also was the first to obtain the coefficients of horizontal turbulent exchange by direct methods.

In 1938 Shtokman was awarded the candidate’s degree in physical-mathematical sciences, without defending a dissertation. In the late 1930’s and early 1940’s he worked in Moscow as director of the hydrology section of VNIRO and as senior staff member at the Institute of Theoretical Geophysics of the U.S.S.R. Academy of Sciences, and during the first years of World War II he was at Krasnoyarsk as senior staff member of the Arctic Institute, which had been evacuated there. During these years Shtokman conducted and published investigations on the theoretical bases of the computation of geostrophic currents from oceanographic measurements: on indirect methods for computing geostrophic currents in the Greenland Sea; on the analysis of water masses of the central part of the northern Arctic Ocean: and on the peculiarities of distribution of Atlantic waters in the Arctic Ocean. Shtokman employed temperature-salt curves in his critical examination of the widely used Jacobsen method of determining the intensity of intermixing of masses of water, and showed that the geometrical part of the method contained serious error. This work led him to research on the application of temperature-salt curves in the analysis of marine water masses, as a result of which a strict theory of these curves (geometry of temperature-salt curves) was developed.

In 1943 Shtokman returned to Moscow, defended his dissertation for the doctorate in physical-mathematical sciences, and began work at the newly created laboratory of oceanography of the Soviet Academy of Sciences, where he remained for the last twenty-five years of his life. During this time the laboratory of oceanography grew into the Institute of Oceanography of the Soviet Academy of Sciences; and Shtokman was director of the section of physical oceanography, the laboratory of ocean dynamics, and the theoretical section.

By the mid-1940’s Shtokman had become widely known as an eminent Soviet specialist in the theory of ocean currents. He made an important step forward from the relations, proposed by Ekman, between currents and wind at a given point of the ocean and discovered the connections between currents and wind over the area of the ocean. Shtokman was the first to show clearly the important role in the dynamics of ocean currents of the transverse irregularities of ocean currents of the transverse irregularities of tangential stress exerted by wind on water. In research published in 1945 he showed that the transverse irregularity of tangential stress of a following wind is an important reason for the horizontal circulation in the ocean. In 1941 Shtokman had shown that the presence of transverse irregularities of tangential stress of a wind over a closed sea inevitably results in countercurrents. The countercurrents exist not only in closed seas, however, but also in the open ocean, particularly in the equatorial zone.

In 1947 Shtokman published a special investigation, Vozmozhny li protivotechenia v bezbrezhnom more, obuslovlennye lokalnoy neravnomernostyu vetra? (“Are Countercurrents Caused by Local Irregularity of the Wind Possible in an Open Sea?”).

The answer was affirmative. In a work published in 1948 Shotokman showed that the main peculiarities of equatorial countercurrents are explained by the dynamic effect of a stable zone irregularity (trade winds) in the lower latitudes.

In 1946 research on the influence of the wind field on currents led Shtokman to develop a theoretical method of computing mean velocities of wind currents as a function of depth—the method of full streams. The closed system of hydrodynamic equations used in this method proved easy to solve and stimulated significant progress in the development of theoretical models of ocean currents for many years. Soon after Shtokman’s work appeared, a method of full streams was developed in the United States by Sverdrup (1947). Unlike Shtokman’s work, which dealt with the basin of a limited area and thus did not consider extensive change in the Coriolis parameter (βeffect), Sverdrup, ;by developing the same method for the open sea, did consider the β effect.

In subsequent research Shtokman sought an easier method of mapping the full streams of the seas of the U.S.S.R., and theoretical model of density that he introduced made it possible to compute approximately the velocity of currents at various depths.

In the last years of his life, Shtokman did mathematical work on the circulation of water, especially around islands in a direction opposite to the circulation in the surrounding ocean. Such a situation occurs in the area around Taiwan in winter and around Iceland and the Kurile Islands throughout the year. In 1966 Shtokman showed that the reason for this phenomenon is the disturbance effect (violation of water exchange), introduced by the island into the horizontal circulation stimulated by the transverse irregularity of wind within the limits of a closed area.

BIBLIOGRAPHY

I. Original Works. Shtokman’s major published writings are “Turbulentny obmen v rayone Agrakhanskogo poluostrova v Kaspyskom more” (“Turbulent Exchange in the Region of the Agrakhansky Peninsula in the Caspinan Sea”), in Zhunal geofiziki. (“On Turbulent Exchange in the Middle and Sothern Parts of the Caspain Sea”), in Izvestiya Akademii nauk SSSR, geog. geophys. sec. (1940), no. 4, 569–592; “O pulsatsiakh gorizontalnykh komponent skorosti morskikh techeny, obuslovlennykh turbulentnostyu bolshogo masshtaba” (“On the pulsations of the Horizontal Components of Velocity of the Ocean Currents Caused by Large-Scale Turbullence”) ibid. (1941), nos. 4–5, 475–486; “Osnovy teorii temperaturno-solenostnykh krivykh, kak metoda izuchnia peremeshivania i transformatsii vodnykh mass morya” (“Bases of the Theory of Temperature-Salt Curves as A Method of Studying the Mixing and Transformation fo Masses of Seawater”), in Proplemy arktiki (1943), no 1, 32–71; “Geometrichekskie svoystva temperaturno-solenostnykh krivykh pri smeshenii trekh vodnykh mass v neorganishennom more” (“Geometrical Properties of Temperature-Salt Curves in the Mixing of Three Water Masses in the Open Ocean”), in Doklady Akademii nauk SSSR. 43 , no. 8 (1944). 351–355: “Poperechnaya neravnomernost nanoy tsirkulatsii v more” (“transverse Irregularity of a Folllowing Wind as One of the Omportant Reasons for Horizontal Circulation in the Ocean”), ibid., 49 , no. 2 (1945), 102–106; and “Teoria ekvatorianlnykh protivotecheny v okeanakh” (“Theory of Equatorial Counter current in the Oceans”), ibid52 no. 4 (1946). 311–314.

Subsequent works are “Uravenia polya polnykh potokov, vozbuzhdaemykh vetrom v neodnorodnom okeane” (“Equations of the Fields of Full Streams Generated by Wind in the Nonuniform Ocean”). in Doklady Akademii nauk SSR, 54 , no 5 (1946). 407–410: “Ispolzovanie analogii mezhdu polnym potokom v more i izgibom zakreplennoy plastiny...” (“Use of the Analogy Between a Full Stream in the Ocean and the Curve of a Strengthened Plate...”), ibid., 54 , no. 8 (1946), 689–692: “Novye dokazatelstva znachenia nervnomernosti vetra kak odnoy iz prichin tsirkulyatsii v more” (“New Proof of the Signiicance of the Irregularity of Wind as One of the Reasons for Circulation in the Ocean”), ibid., 58 no. 1 (1947), 53–56; Ekvatorialnye protivotechenia v okeanakh (“Equatorial Countercurrents in the Oceans”; Leningrad, 1948); “Issledovanie vliania vetra i relefa dna na rezultiruyushchuyu tsirkulyatsiyu i raspredelenie mass v neodnorodnom okeane ili more” (”

REsearch on the Influence of Wind and the Surface of the Bottom on the Nonuniform Ocean or Sea”). in Trudy Instituta okeanologii Akademiii nauk SSSR3 (1949), 3–65; “Vlianie vetra na techenia v Beringovom prolive...” (“Influence of the Wind on the Currents in the Bering Strait...”), Ibid., 25 (1957), 17–24: “Ob odnoy probleme dinamiki okeanichekoy tsirkulystsii” (“On One problem of the Dynamics of Ocean Circulation”), in Simpozium po matematicheskim i gidrodinamicheskin methodam izuchnia fizicheskikh protsessov v okeane, Moskva, 25–28 maya 1966, tezisy dokladov (“Symposium on Mathematical and Hydrodynamical Methods of Studying the Physical Processes in the Ocean... Abstracts of Reports”; Moscow, 1966), 60–61; and Razvitie teorii morskoy i okeanicheskoy tsirkulyatsii v SSR za 50 let” (“Development of the Theory of Sea Ocean Circulation in the U.S.S.R. for Fifty Years”), in Okeanologia, 7, no. 5 (1967), 761–773.

II. Secondary Literature. See the obituaries by his editorial collegues, “Vladimir Borisovich Shtokman,” in Lzyestiya Akademii nauk SSR, Fiz. atmos. i okeana Shtokman,” in Okeanologia, 8 no. 4 (1968). 771, by a group of his colleagues.

A. F. Plakhotnik