Study on the Boundary Mixing and Intrusion of Shelf Water into the Intermediate Layr of the Kuroshio around the Continental Shelf Break

1995年11月10日至12日，获得了东海大陆架断裂附近跨陆架断面的温度、盐度和浊度垂直剖面。大多数测量站的底部上方都检测到了高浊度水。斜坡区中层可检测到较高浊度水体，剖面上呈等重面分布，表明陆架底部正上方的高浊度水体应侵入黑潮。 1996年11月的小间距观测点观测发现，陆架区低盐度水侵入黑潮的证据明显。然而，1996年，低盐度水的来源似乎并不位于陆架底部附近，而是起源于陆架区域的表层附近，入侵水体的浑​​浊度没有明显区别。黑潮下游方向相距5海里的两段入侵体结构变化不大，表明入侵体的沿陆架尺度至少大于10公里。用停泊在陆架断口周围250m水深的海流计进行的另一次测量，检测到了多种时间尺度的内波。 1995年11月停泊两天，采样间隔为1分钟，在海底120和60m处的海流处间歇性地看到内潮、10至30分钟多个周期的短时标内波以及更短时标的湍流波动。虽然目前尚不清楚内波与湍流或垂直混合有何关系，但上述入侵可能是由频繁发生的湍流或小尺度内波的破碎而产生的。

During 10 to 12 November, 1995, vertical profiles of temperature, salinity and turbidity were obtained along a cross-shelf section near the continental shelf break in the East China Sea. High turbidity water was detected just above the bottom at most of the measuring stations. And relatively high turbidity water could be detected in the intermediate layr of the slope region, which distributed along an isopycnal surface on the section, suggesting that the high turbidity water just above the bottom of the shelf should intrude into the Kuroshio. From the observations with short spacing in observation points in November, 1996, it was found that distinct evidence of intrusion of low salinity water from the shelf area into the Kuroshio. However, in 1996, origin of the low salinity water seemed to not be located near the bottom of the shelf but originated around surface layr in the shelf region, and there were no significant distinction in turbidity in the intruded water. The structure of the intrusion did not change so much between two sections with 5 miles distance in down stream direction of the Kuroshio, which indicated that the along-shelf scale of the intrusion would be larger than 10 km at least.Another measurements with current meters moored at 250m water depth around the shelf break detected internal waves with several kinds of time scale. In two days mooring with 1 minute sampling interval in November 1995, internal tide, short time scale internal waves with the several periods from 10 to 30minutes along with shorter time scale turbulent fluctuations were seen intermittently from current meters at 120 and 60m above the bottom. Although it was not clear how the internal waves related to turbulence or vertical mixing, above mentioned intrusion could be generated by frequent occurrence of turbulence or breaking of small scale internal waves.