THE POLYGON-70 EXPERIMENT. BEGINNING OF A NEW STAGE IN THE HYDROPHYSICAL STUDIES OF THE WORLD OCEAN (To the 50th anniversary of the discovery of oceanic synoptic vortices)

Abstract

Fifty years ago, in 1970, open ocean eddies of the synoptic scale were experimentally found during the expedition within the Soviet Oceanographic Program Polygon-70 carried out in the subtropical zone of the North Atlantic. This turned out to be one of the most significant events in oceanology of the twentieth century. Unlike the previously known similar circulation structures that usually separated from large-scale jet streams, the newly discovered eddies were free, that is, they had essential inertial wave character. The velocities in such eddies often exceeded the mean mesoscale ocean current velocity. By analogy with cyclones and anticyclones in the atmosphere, free eddies of the open ocean, which have spatial and temporal scales similar to the atmospheric eddy formations, were called SYNOPTIC eddies. This term is used in the Russian literature. The history of the Polygon-70 experiment and its main results are described. Brief information is given about other major international and that of Shirshov Institute of Oceanology "polygon" programs for the study of mesoscale eddies.