Construction of real time monitoring system of the Tsushima Current using a ferryboat between Hakata and Pusan

点击翻译按钮获取中文摘要

Research Institute for Applied Mechanics, Kyushu University has been monitoring the current structures on the vertical section along the cruise line of a regular ferryboat (Camellia) between Hakata and Pusan using ADCP(Acoustic Doppler Current Profiler) mounted to the ferryboat since February in 1997. The ferryboat made round trips three times a week until February in 2004 and the new ship introduced from July in 2004 makes six times a week. Observed data were recovered once a month before the middle of 2001 from the beginning. However, the newly introduced real time data transferring system using telephone network by this scientific research fund made possible almost real time monitoring of the Tsushima current. Data were recovered three times a week until February in 2004 from the middle of 2001 and six times a week since the introduction of new ship in July in 2004. Those data were used for the research of the Japan Sea circulation and the prediction system of the Japan Sea as boundary conditions. Parts of these data are also accessible through our web page(http://nmg.riam.kyushu-u.ac.jp/~camellia/).Those data clarified many aspects of the Tsushima Current such as the current structure and volume transport, and those seasonal and inter annual variabilities. An empirical equation was proposed to estimate the volume transport of the Tsushima Current using sea level differences between Hakata, Izuhara and Pusan. This equation makes also possible the estimation of past change of volume transport as long as sea level data were obtained. In addition, one hour interval of sea level data made a great progress in the study of short term(a couple of days) variabilities which are greatly attributed to non-isostatic response of the Japan Sea to atmospheric pressure disturbances with energy peak at 3-5 days.