Physical Oceanography, Vol. 17, No. 2, 2007
TRANSFORMATION OF BLACK-SEA WATERS IN THE SEA OF MARMARA
A. S. Zapevalov and S. V. Dovgaya
The analysis is performed on the basis of comparison of the hydrological characteristics of pre-
strait regions of the Sea of Marmara. It is shown that, in summer, the Black-Sea waters are
weakly mixed with the Mediterranean waters and the levels of salinity in the prestrait regions
0.6-0.9‰. In winter, the indicated difference increases and the level of salinity near the
entrance of Dardanelles reaches
and exceeds the level observed near the entrance of Bos-
5.5‰. In the analyzed regions, we observe local temperature maxima and minima near
the interface of two water masses. This is explained by the presence of strong seasonal varia-
tions of temperature for the Black-Sea waters and their absence for the Mediterranean waters.
The physical mechanisms responsible for the seasonal variations of the intensity of transforma-
tions of the Black-Sea waters are discussed.
The investigations carried out by Russian researchers more than one hundred years ago made it possible to
clarify the principal features of hydrology of the Sea of Marmara [1, 2]. These studies were continued in the first
half of the last century  and in the recent works [4, 5]. Nevertheless, some details of the observed picture still
The hydrology of the Sea of Marmara is formed as a result of water exchange through the narrow straits
connecting this sea with the Aegean and Black Seas. The existing significant difference between the levels of
salinity in the Aegean and Black Seas leads to the formation of a well-pronounced two-layer structure of waters.
The upper layer
in thickness) is occupied by lighter Black-Sea waters and the lower layer is occupied
by heavier Mediterranean waters . The existing high density gradient on the interface of these two water
masses weakens the process of vertical exchange. As a result, the Black-Sea waters are weakly mixed with the
Mediterranean waters occupying the lower layer. Therefore, the indicated two-layer structure is observed in the
entire water area of the Sea of Marmara.
The Turkish system of straits (including Bosporus, Dardanelles, and the Sea of Marmara) is an important
element specifying the hydrology of the Black and Aegean Seas . The inflow of Black-Sea waters is well vis-
ible in the north part of the Aegean Sea according to the data of remote sounding in the infrared and visual regi-
ons. Note that the frontal zones separating the Black-Sea and Mediterranean water masses and their location are
characterized by strong seasonal variability .
Array of Hydrological Data
The aim of the present work is to analyze the transformations of Black-Sea waters between Bosporus and
Dardanelles. The analysis is performed on the basis of the data stored in the database of the Marine Hydrophysi-
cal Institute of the Ukrainian National Academy of Sciences .
Marine Hydrophysical Institute, Ukrainian Academy of Sciences, Sevastopol.
Translated from Morskoi Gidrofizicheskii Zhurnal, No.
49–55, March–April, 2007. Original article submitted April 25, 2005;
revision submitted October 24, 2005.
106 0928-5105/07/1702–0106 © 2007 Springer Science+Business Media, Inc.