Seasonal variation in the material flux from Tokyo Bay to the Pacific Ocean

时间序列泥沙捕集器、流速仪和浊度计在距海底100m处系泊在STN。东京湾出海口T1(北纬35.2度，北纬139.44度，东经800米)，1994年5月至1995年10月。每周采集一次泥沙通量数据，每30min采集一次水流、水温、盐度和浊度数据，春季和秋季泥沙通量增大，泥沙通量增大时浑浊度较高。建立了东京湾余流的三维数值模型，揭示了东京湾余流的季节变化规律。春季和夏季东京湾头部的逆时针剩余环流增强，秋季和冬季东京湾中部的顺时针剩余环流增强。我们将在近期利用所开发的数值模式再现东京湾入海口下沉通量的季节变化。

Time-series sediment trap, current meter and turbidity meter were moored 100 m above the bottom at Stn. T1 (35.2, N,139.44, E,depth is 800 m), the mouth of Tokyo Bay, from May 1994 to October 1995. The data of sediment flux were obtained every week, those of current, water temperature, salinity and turbidity every 30 minutes.Sediment flux was increased in spring and autumn and turbidity was high at the time when the sediment flux was increased. Moreover, sediment flux was increased eventually when the heavy rain was fallen or the front of Kuroshio approached to the coast.We developed three-demensional numerical model of the residual flow in Tokyo Bay and revealed the seasonal variation in the residual flow in Tokyo Bay. The anticlockwise residual circulation in the head region of Tokyo Bay is intensified in spring and summer and the clockwise residual circulation in the central part of Tokyo Bay is intensified in autumn and winter.We will reproduce the observed seasonal variation in sinking flux at the mouth of Tokyo Bay with use of the developed numerical model in the near future.