Formation and propagation of the Aleutian eddy

Aleutian eddies are anticyclonic eddies which form south of the Aleutian Islands between 170°E and 175°E and propagate southwestward. In this study we investigated formation and propagation of the Aleutian eddy through analysis of 18-year time series of satellite altimeter data distributed by AVISO. Neighbor enclosed area tracking algorithm was applied to track each eddy identified using Okubo-Weiss parameter. Zero to five Aleutian eddies were formed per year and the number of Aleutian eddy formed per year changed with a period of three to four years. Meanwhile, the propagation route of the Aleutian eddy did not show marked interannual variation. Most of the Aleutian eddies propagate toward the center of western subarctic gyre; the rest propagate toward Kamchatka Peninsula or into the Bering Sea.