Evolution, movement and decay of warm-core Leeuwin Current eddies

Characteristics of eddies originating in the Leeuwin Current (LC) have been investigated using 10-day sea-level anomaly maps of combined TOPEX/POSEIDON and ERS altimeter data for the period 1995–2000. During these 6 years, 37 long-lived anticyclonic eddies were tracked from the west coast of Australian to 90°E. Between three and nine eddies were spawned each year, and their trajectories are described in detail. Most long-lived eddies are generated in May–June, when the LC is most intense, and at three preferred locations: 20–21.5°S, 24–25°S and 28°–31°S. The temporal evolution and latitudinal variations of the sea-level anomalies and their radius and drift speed are discussed. Topography plays an important role in the evolution and structure of the eddies. Interactions with topography can induce splitting or merging of eddies which further affects the eddy decay.