A RELATIONSHIP BETWEEN LOCATION OF THE SP ECIFIC ISOPYCNIC LAYER AND THE UPPER BOUNDARY OF THE H2S-ZONE IN THE BLACK-SEA FROM MULTIANNUAL DATA

A relationship between location of the specific isopycnic layer and th e upper boundary of the anoxic water has been determined from the aver aged historical data. The paper emphasizes the principal role of the h ydrophysical and hydrologic factors in the global processes responsibl e for the interannual variability of the location of the H2S-zone's up per boundary, Probably, the upper boundary of the H2S zone produces os cillatory movements in time with approximately a century period.