著者

洪 鉄勲 尹 宗煥

出版者

日本海洋学会

雑誌

海の研究 (ISSN:09168362)

巻号頁・発行日

vol.1, no.5, pp.225-249, 1992-10-26

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The effect of typhoon on the sea level variations at three tidal stations in Pusan, Izuhara, and Hakata in the Tsushima / Korea Strait is studied by using hourly sea level data and numerical experiments. The characteristic features of the sea level variations at these three tidal stations are found to be: (1) the existence of the time-lag between the maximum sea levels at these stations (2) the persistence of the high sea level at Pusan for about a week even after the passage of the typhoon and (3) the occurrence of oscillations with a period of about 2.5 days after the passage of the typhoon. The results of the numerical shallow water experiments with the high resolution (1/12^0 × 1/12^0) explain well the observed features of the sea level variations at three stations above. The time-lags between the maximum sea levels are caused by the difrerent response of the sea levels at each station to the typhoon. In Pusan and Izuhara, the sea level responds isostatically to the atmospheric pressure as the typhoon approaches to these stations, while in Hakata, there develops the southwestward coastal flow which is driven by the southwestward wind accompanied by the typhoon and cancels the increase of the sea level due to the isostatic response to the atmospheric pressure by the typhoon. The high sea level at Pusan after the passage of the typhoon may be maintained by the southwestward coastal current along the south Korean coast which is driven by the large scale cyclonic eddy formed in the Japan Sea by the typhoon, although the duration in the model is shorter than the observed one. The oscillation of about 2.5 days period after the passage of the typhoon seems to be a basin scale oscillations due to the propagation of Kelvin wave generated by the typhoon.