Physical Oceanography, Vol. 17, No. 5, 2007
SPECTRA OF THE BLACK-SEA TSUNAMIS
S. F. Dotsenko and A. V. Ingerov
We perform the analysis of the time spectra of four tsunamis generated in the Black Sea by the
earthquakes of 26.07.1927, 11.09.1927, 26.12.1939, and 12.07.1966. For the analysis of the
spectra, we used digitized marigrams obtained for 12 points of the Black-Sea coast.
spectra are, as a rule, multimode and have 1–4 spectral maxima. One maximum corresponds to
the periods typical of tsunami waves and the other maxima correspond to the oscillations of the
sea level with lower frequencies. It seems likely that the events of tsunami are accompanied by
low-frequency oscillations of the level caused by the atmospheric forcing, seiches, or other fac-
tors. In numerous cases, the oscillations from the predominant energy range lie outside the char-
acteristic range of periods of the tsunami waves.
The level of tsunami hazard in the Black Sea is much lower than, e.g., in the Pacific Ocean, Caribbean Bas-
in, or Mediterranean Sea . Although the events of tsunami were observed in the Black-Sea basin and some of
them were catastrophic, the recurrence of the events noticeably affecting the social and economic situation in the
coastal regions of the sea is quite low and equal to decades or even centuries. The available volume of the data
of measurements of sea level corresponding to the period of Black-Sea tsunamis with time intervals required for
the analysis is very small. At the same time, the level of seismic activity in the Black-Sea depression and the
worldwide experience of investigations of the problem of tsunamis do not enable us to exclude the possibility of
excitation of catastrophic tsunamis in the Black Sea with seismic and/or landsliding sources of generation.
There exists a small amount of data of instrumental observations over the seismogenic oscillations of the
sea level carried out at different points of the Ukrainian, Russian, and Georgian parts of the Black-Sea coast.
The generalized descriptive data and the quantitative characteristics of the recorded tsunami waves can be found
The indicated quantitative characteristics of the Black-Sea tsunamis at various points of the coast were re-
vised and corrected in . Moreover, some additional parameters of oscillations of the sea level accompanying
tsunamis were presented. This analysis was based on the results of digitalization of all available marigrams. In
what follows, the obtained time realizations are used for the evaluation and analysis of the time spectra of oscil-
lations of the Black-Sea level accompanying the tsunamigenic earthquakes of 1927, 1939, and 1966. The spectra
of some Black-Sea tsunamis were also considered in  with an aim to determine the periods of predominant
Database and the Procedure of Analysis
The historical events of tsunami during which the oscillations of the sea level were recorded by marigraphs
are of especial interest for the evaluation of the parameters of tsunami waves near the Black-Sea coast.
Marine Hydrophysical Institute, Ukrainian Academy of Sciences, Sevastopol.
Translated from Morskoi Gidrofizicheskii Zhurnal, No.
21–30, September–October, 2007. Original article submitted April 5,
0928-5105/07/1705–0269 © 2007 Springer Science+Business Media, Inc. 269