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

九州大学应用力学研究所自1997年2月以来一直在使用安装在渡船上的ADCP（声学多普勒海流剖面仪）监测博多和釜山之间的定期渡船（山茶）的巡航线上沿着垂直截面上的当前结构。该渡船每周往返三次，直到2004年2月，新船从2004年7月开始每周往返六次。从2001年中期开始，观测数据每月恢复一次。然而，该科研基金新引进的利用电话网络的真实的时间数据传输系统使对马海流的几乎真实的时间监测成为可能。从2001年中期到2004年2月，数据每周恢复三次，自2004年7月引进新船以来，每周恢复六次。这些数据被用于研究日本海环流和日本海预报系统作为边界条件。这些数据的一部分也可以通过我们的网页（http：//nmg.riam.kyushu-u.ac.jp/camellia/）获得。这些数据澄清了对马海流的许多方面，如海流结构和流量输送，以及季节和年际变化。利用博多、伊津原和釜山之间的海平面差异，提出了一个估算对马海流输量的经验公式。只要获得海平面数据，该方程还可以估计过去的体积输送变化。此外，一小时间隔的海平面资料在短期（几天）变化的研究方面取得了很大进展，这主要归因于日本海对大气压扰动的非均衡响应，其能量峰值在3-5天。

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.