| Abstract: | Unstable wave disturbance parameters and their seasonal variability are considered using a multi-level quasi-geostropic model of a large-scale current. It has been postulated that hydrodynamically unstable processes become more intensive during the winter-spring period, with the dominating wavelength being 600 km and the period 350 days. The decay of the Equatorial Countercurrent in spring is related to a mixed type of hydrodynamic instability and to the generation of planetary waves. During the summerautumn period, when the Equatorial Countercurrent's hydrodynamic instability is developing, meandering occurs, with the lengths of the waves, slowly migrating across the ocean in an easterly direction, being  950–1500 km.Translated by V. Puchkin. |
