Steric oscillations of the Black Sea level

Steric oscillations of the Black Sea level are studied in the paper using two approaches. Firstly the peculiarities of spatial oscillations are considered the level being calculated with respect to the reference average station and a reference steric level is obtained as a result. It is an analog of the dynamic surface topography of the Black Sea. Secondly the temporal steric oscillations of the level are studied. The oscillations in the spatial trapeziums of averaging are centered (that is to say that they are brought to a zero mean value) with respect to the annual average level values in these trapeziums. The contribution of certain components of the steric level are estimated: thermic and saline. The annual and semi-annual harmonics of the steric oscillations are calculated together with their phases. It is shown that double amplitudes of the steric oscillations reach 20 cm and it presents 80% of the general level oscillations in certain regions of the Black Sea. The physical processes are found which govern the character of the steric level oscillations and its saline and thermic components.