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The paper describes the conditions of formation of large accumulative forms on the southeastern coast of the Baltic Sea and presents the results of a comparative analysis of these structures. It has been established that Baltic barrier-lagoon systems have a complex geological and geomorphologic structure. Sandy barriers, which are, in general, marine accumulative formations, often comprise various fragments of different genesis (moraine remnants, glaciolacustrine and deltaic plains, etc.). The formation and development of large accumulative forms in the southeastern Baltic occurred against the background of sea level fluctuations in the Littorina time following a unified scenario for the entire coast. [ABSTRACT FROM AUTHOR]

The tides in the Baltic Sea are weak but unmistakably recognizable in sea-level spectra. Multiyear hourly tide gauge series enable us to examine specific tidal properties in detail and to identify some unexpected effects. Two nearby stations on the southeastern coast of the sea, namely Baltiysk, located in the strait connecting the Vistula Lagoon to the Baltic Sea, and Otkrytoe, on the coast of the Curonian Lagoon, are found to have very different character of tidal motions. Based on 13 years of simultaneous observations at these stations we constructed high-resolution spectra of sea level fluctuations that demonstrated that the tidal spectrum at Baltiysk is 'classical' with sharp peaks corresponding to the major tidal constituents: M, S, N, K, O, and P. Unlike at Baltiysk, the main tidal peak at Otkrytoe is at the S frequency; the K, P, and S tidal harmonics also have significant peaks, while the other harmonics (including M and O) are undistinguishable. Further analysis indicated that the tides at Baltiysk are generated by ordinary gravitational tidal forces, while at Otkrytoe they are induced by solar radiation, specifically by the breeze winds creating wind setups and setdowns in the Curonian Lagoon. Moreover, our findings demonstrate that the observed K and P peaks at Otkrytoe are related not to gravitational forces but to the seasonal modulation of the S radiational tidal constituent. The separate analysis of the 'summer' and 'winter' sea level spectra at Otkrytoe reveals prominent radiational tidal peaks (S and S) in summer and the absence of these peaks in winter. The results of the analysis support the assumption that these motions are generated by the breeze winds associated with the sea/land temperature contrasts, which are substantial during the warm (ice-free) season but vague during the cold season when ice cover diminishes these contrasts. [ABSTRACT FROM AUTHOR]