Modeling of the nearshore branch of the Tsushima Warm Current with data assimilation

Kawamura, Hideyuki  ; Ito, Toshimichi ; Hirose, Naoki*; Yoon, J.-H.*; Takikawa, Tetsutaro*

An assessment system for oceanic environment in the Japan Sea has been developed at Japan Atomic Energy Agency. Realistic reproduction of oceanic condition such as current and temperature is necessary to calculate movement of materials in the ocean. A circulation in the Japan Sea is strongly effected by the Tsushima Warm Current through the Tsushima Straits and the Tsugaru Warm Current through the Tsugaru Strait. In this study, an ocean general circulation model was drived by realistic volume transports of the Tsushima Warm Current and the Tsugaru Warm Current observed by Kyushu University and JAEA, respectively. In addition, the satellite altimeter data and sea surface height at coastal stations were assimilated by the Kalman filter. Model results well reproduced current field along the Japanese coast observed from September to October in 2000.