Structure of the Kuroshio West of Kyushu

摘要

A triangular CTD/ADCP survey was made across the Kuroshio west of Kyushu aboard the R/V THOMPSON during January, 1986 in order to investigate the water properties and flow field in the Kuroshio. A similar CTD survey was made in July, 1986 aboard the R/V WASHINGTON to study the seasonal variability in the Kuroshio. The Kuroshio in the region exhibited a marked seasonal change in its near-surface stratification and water properties. In January, the Kuroshio water was separated from the vertically well-mixed coastal water over the shelf by a strong front located near the shelf break. Horizontal mixing between the Kuroshio and coastal water was observed but was limited near the shelf break. In July, surface coastal water extended far past the shelf break over the Kuroshio region near the surface and, in turn, Kuroshio water intruded into the shelf near the bottom. Mixing between the Kuroshio and coastal water was found over much of the mid and outer shelf and upper slope, spanning a cross-stream distance of 75 km. In addition, evidence of deep vertical mixing within the Kuroshio itself was found near 32.0 N and 128.2 E., most likely due to internal tidal mixing over the slope. (Copyright (c) Changsheng Chen 1989.)