[A-OS18] Kuroshio Large Meander

[AOS18-P04] Study on the temporal and spatial variation of the Kuroshio Current path

*Yuya Hirano¹, Kazuyuki Uehara¹ (1.Graduate School of Earth Environmental Science, Tokai University)

Keywords: Kuroshio detachment distance, Wavelet analysis

Kawabe (1995) classified the Kuroshio flowing along the southern coast of Honshu into three flow patterns: non-Large-Meander path (nearshore and offshore) and Large-Meander path. After this study, studies has been reported to show pattern of the Kuroshio Current paths, but the time-varying characteristics of the flow pattern have not been discussed. In this study, we therefore extracted the flow paths from the sea surface dynamic height data, then conducted time-frequency analysis for the Kuroshio detachment distance from the coast. In the result, we found the clear difference in periodicity from east to west, with the Kii Peninsula offshore as a border. West of the Kii Peninsula, the dominant peaks seen off southeast Kyushu at 30 days or less, 90-180 days, and 360 days gradually weakened while moved toward the Kii Peninsula. On the other hand, east of the Kii Peninsula, the stronger peaks with various periods were observed get closer to the Izu-Ogasawara Ridge.