동해의 울릉분지와 야마토 분지 사이의 직접적인 흐름

Abstract

Over the southern part of the East/Japan Sea using the trajectories of ARGO floats, we show that there are robust direct flows from the Ulleung Basin into the Yamato Basin through a gap between the Oki Spur and the Yamato Rise. The gap is subdivided into two narrow (northern and southern) passages by a seamount located in the middle. The flows, therefore, are very narrow and this explains why this flow was not reported earlier. A high resolution regional ocean model that is consistent with current meter moorings and ARGO data in general shows that the mass flux through the gap below 200 m is about 1.8 Sv. The flows through the gap, especially those through the southern passage, are well correlated with the southward current along the eastern coast of Korea found below the thermocline, the North Korea Cold Current. A mass budget calculation shows that along with this current, eastward flows crossing the mouth of the Ulleung Basin supply the flow though the gap. Considering that the strength of the meridional overturning in the EJS is on the order of 1 Sv., the flow through the gap constitutes an important component of the deep circulation. Thus, the narrow gap, where the flow is a wellconfined, would be a good place to study the deep circulation.