Physical Oceanography, Vol. 14, No. 1, 2004
ASSIMILATION OF THE DATA OF SATELLITE ALTIMETRY IN AN
EDDY-RESOLVING MODEL OF CIRCULATION OF THE BLACK SEA
V. L. Dorofeev and G. K. Korotaev
The data of satellite altimetry are used to simulate the Black-Sea circulation. The altimetry data
of the TOPEX/Poseidon and ERS satellites are prepared within the framework of the NASA
Ocean Altimeter Pathfinder project. The additional data processing is performed to compute the
dynamic level reflecting the circulation of the Black Sea. The altimetry sea-level is assimilated
in an eddy-resolving model of circulation of the Black Sea based on primitive equations. The
accuracy of the obtained fields of temperature and salinity is estimated by comparing with the
data of large-scale hydrographic surveys according to the ComSBlack program. The prognostic
capabilities of the proposed model are estimated by comparing the obtained results with the
fields computed with the help of assimilation of the altimetry data.
The Black Sea is one of the largest inland seas in the world. It is connected with the Atlantic ocean by a
chain of seas and narrow straits. Its basin has a simple coastal line without large gulfs and islands. The Crimea
is the sole significant peninsula splitting the deep-water part of the sea into two almost symmetric parts. The
maximum deep in the central part of the sea attains
km. The discharge of rivers located mainly in the north-
west shelf zone and the inflow of salt waters through Bosporus form a field of salinity, which makes the princi-
pal contribution to the density stratification of the Black Sea. A constant pycnocline is located in the sea at
m. As a unique specific feature of the thermal stratification of the basin, one can men-
tion the presence of a cold intermediate layer. The temperature in its core is lower than
8°C. This layer is
formed as a result of winter convection in the northwest shelf zone or in the domes of cyclonic eddies and loc-
ated at depths of
m. Below the cold intermediate layer, the temperature of water increases with depth.
This is explained by the presence of both geothermal flows and deep convection of warm and salty water of the
Sea of Marmara coming through Bosporus.
The most pronounced specific feature of the Black-Sea circulation in the upper layer is the Rim Current.
This current flows around the Black Sea along its perimeter and forms a large-scale cyclonic gyre. In winter, the
main gyre splits into two smaller gyres in the west and east parts of the basin. The data of large-scale hydrologi-
cal surveys, satellite observations, and eddy-resolving numerical computations reveal the presence of intense
synoptic variability in the Black Sea, which distorts the simple structure of the gyres. The intense meandering of
the Rim Current is observed over the continental slope of the northwest shelf zone and in the east part of the
Anatolian Coast. To the right of the main stream of the Rim Current, we observe quasistationary mesoscale anti-
cyclones. From the statistical point of view, these anticyclones can be regarded as an element of the seasonal cy-
Marine Hydrophysical Institute, Ukrainian Academy of Sciences, Sevastopol. Translated from Morskoi Gidrofizicheskii Zhurnal,
52–68, January–February, 2004. Original article submitted July 16, 2002; revision submitted July 22, 2002.
42 0928-5105/04/1401–0042 © 2004 Plenum Publishing Corporation