Synoptic Eddies in the Ocean

Synoptic oceanic eddies are defined as nonstationary eddylike disturbances of the oceanic circulation with a horizontal scale of the order of the Rossby internal scale R = NIif-l, wherefis the Conolis parameter, h the thickness of the baroclinic layer in the ocean, and N the average over the baroclinic layer Viiisiila frequency; in the internal parts of the anticyclonic subtropical gyres R is of the order of 50 km. The use of the term instead of the term mesoscale emphasizes the physical analogy between the phenomenon under consideration and the synoptic eddies in the atmosphere (cyclones and anticyclones). This analogy can be made on the basis of their similar physical natures (Ro ssby waves, the determining role for which is played by the Corio lis parameter), the suggested prevailing mechanism of generation (baroclinic instability of large-scale currents), the corresponding horizontal scales (Rossby atmospheric and oceanic scales) and in the quasi-geostrophi