Space-Time Structure and Identification of Synoptic Disturbances of the Baltic Sea Level from Satellite Altimetric Measurements

E. A. Zakharchuk, Yu. P. Klevantsov, and N. A. Tikhonova

Characteristics of synoptic level variations in the range of periods from a few weeks to months obtained from satellite altimetric measurements are analyzed on the basis of frequency spectral analysis of the Baltic Sea level. It is shown that synoptic variations with periods from 30 to 92 days have space scales from about 250 to 1400 km and propagate in different directions at a velocity of 7–31 cm/s. Comparison of altimetry-derived characteristics of synoptic level variations with dispersion relations of low-frequency waves made it possible to identify them as barotropic and baroclinic Rossby waves and baroclinic topographic waves.