Otto Pettersson’s ideas on general ocean circulation

Originally a physical chemist, Pettersson became deeply interested in physical and chemical oceanography (hydrography) when analysing measurements of the "Vega'' expedition in 1878-1880 around Eurasia. He wrote a paper on ice conditions in which he displayed fascination for the relationship between the system of ice formation in the Arctic Ocean and the melting far to the south. At the turn of the century, he published his hypothesis stating that melting ice caused deepwater movements. A 10-year heated debate began between Pettersson and Nansen, who favoured atmospheric cooling and (possibly) ice formation as the cause of deepwater flow. Pettersson was skeptical of Zöppritz’s hypothesis that the wind, apparently driving the equatorial surface currents, would be able to penetrate to the bottom and thereby drive deep currents. When Ekman presented his theory in 1902, in which the wind current was shown to be very shallow, Pettersson was pleased. When the same author demonstrated three years later that the wind in the presence of coasts could make its influence felt at the greatest depths, Pettersson protested. Concerning the recent appreciation of the North Atlantic Oscillation, there is a link back to Pettersson. His article in 1896 was highly appreciated by Meinardus because it connected the Gulf Stream Extension variations with a meteorological parameter (air temperature). Meinardus, however, showed atmospheric pressure to be a much more practicable tool. In the opinion of the present author, Pettersson had an early but realistic view of the currents of the Nordic Seas. Later, however, he found that a pattern complying with his ice-melting hypothesis also explained the transport of Arctic plankton to the Skagerrak.

Article from Marine Science Symposia Vol. 215 - 100 years of science under ICES. To access the remaining articles please click on the keyword "MSS Volume 215".