Trajectories of mesoscale eddies in the Kuroshio recirculation region were investigated by using sea surface height (SSH) anomaly observed by the TOPEX/POSEIDON and ERS altimeters. Cyclonic and anticyclonic eddies have been traced on maps of the filtered SSH anomaly fields composed from the altimeter observations every ten days. Both the cyclonic and anticyclonic eddies propagate westward in the Kuroshio recirculation region from a region south of the Kuroshio Extension. The propagation speed of these eddies has been estimated as about 7 cm s-1, which is much faster than the phase speed theoretically estimated for the baroclinic first-mode Rossby wave in the study area. It was also found that in the Izu-Ogasawara Ridge region, most of eddies pass through the gap between the Hachijojima Island and Ogasawara (Bonin) Islands, and some of the eddies decay around the Izu-Ogasawara Ridge. It seems that the trajectory of the eddies is crucially affected by the bottom topography. In the region south of Shikoku and east of Kyushu, some of the eddies coalesce with the Kuroshio. It is also suggested that this coalescence may trigger the path variation of the Kuroshio in the sea south of Japan.
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