Physical Oceanography, Vol. 15, No. 1, 2005
INDICATRICES OF SCATTERING OF LIGHT AND THE COMPOSITION OF
SUSPENSION IN THE BLACK SEA
V. I. Man’kovskii and M. V. Solov’ev
We analyze the data of measurements of the indicatrices of scattering of light in the Black Sea in
winter 1991 and summer 1998, present their principal characteristics, and discuss their correla-
tions and spatial variability. The data on scattering of light are used to determine the number and
weight concentrations of various fractions of particles suspended in water. The characteristics of
scattering of light and the composition of suspension in the Black Sea are compared with the data
obtained in 1973 and with the data accumulated in the Aegean and Ionian Seas and in the Indian
The first data on the indicatrices of scattering of light in Black-Sea waters were obtained in 1970–1973 .
These years were characterized by a high transparency of water:
(the annual average depth of
visibility of the Secchi disk ). Since the second half of the 1980s, as a result of the influence of anthropogenic
and natural factors, the marine ecosystem suffered significant changes as a result of which the transparency of
waters decreased and their productivity (trophic conditions) improved. Thus, in 1992, the annual average value
was equal to
m. In the subsequent years, this value increased but did not reach the indicated high val-
ues observed in the 1970s.
In 1997–2002, the values of
varied within the range
In this connection,
it seems necessary to analyze the data on the indicatrices of scattering of light for the new state of the marine
In the present work, we discuss the characteristics of the indicatrices of scattering of light measured in 1991
m and in 1998 for Z
m. In 1991, the measurements were carried out in the course of Cruise
54 of the R/V Mikhail Lomonosov (17.11–13.12.1991) in a large-size test range located in the north part of the
sea. In 1998, the measurements were carried in the course of Cruise 2 of the R/V Gorizont (01–04.12.1998) in
a small test range located to the west of the Crimean Peninsula in the zone of the Black-Sea Rim Current.
The shape of the indicatrix of scattering of light depends on the composition of particles suspended in wa-
ter. Thus, the indicated composition can be determined as a result of the solution of the inverse problem. The
corresponding calculations were carried out according to the measured indicatrices and the characteristics of par-
ticle and weight concentrations of various fractions of the suspension in the surface and abyssal waters of the
Black Sea were determined for the first time.
Equipment and Procedure
The measurements were carried out with the help of a nephelometer  at a wavelength of
Samples of water were taken from the sea surface and abyssal levels by using a plastic pail and the bathometer of
an STD-probe, respectively.
The following characteristics of scattering were calculated:
Marine Hydrophysical Institute, Ukrainian Academy of Sciences, Sevastopol.
Translated from Morskoi Gidrofizicheskii Zhurnal, No.
63–76, January–February, 2005. Original article submitted August 5,
2003; revision submitted October 3, 2003.
0928-5105/05/1501–0057 © 2005 Springer Science+Business Media, Inc. 57