Deep countercurrent beneath the Kuroshio on the continental slope in the East China Sea

东海大陆坡黑潮下的深层逆流

基本信息

批准号：
16340142
负责人：
NAKAMURA Hirohiko
金额：
$ 7.17万
依托单位：
Kagoshima University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2004
资助国家：
日本
起止时间：
2004 至 2006
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-16340142/
关键词：
Kuroshio Continental slope Deep countercurrent East China Sea Oceanic observation Current Moored current meter self-organization 陸棚斜面

项目摘要

Previous observations have indicated that the deep countercurrent is present beneath the Kuroshio on the continental slope in the East China Sea. However, its persistency and spatial extent along the continental slope have not been clarified as yet. We carried out 2-years moored current meter measurements at four locations in the slope area near 27-29° N, and observed ten snapshots of velocity and hydrographic sections containing the deep countercurrent for the period November 2004 and November 2006. The deep countercurrents were clearly identified to the velocity records in which high-frequency fluctuations (periods shorter than about 20 days) due to Kuroshio front meanders were removed. Structures of the deep countercurrent had differences between the central and northern slope areas, the boundary of which corresponded to the climatological mean position where the Kuroshio separates from the continental slope. The location of the deep countercurrent was deeper in the central slope area than in the northern one. The deep countercurrent had a clear season-fixed nature especially in the central slope area, i.e., periodic countercurrents that vary with periods of 1-2 months were organized into a persistent countercurrent in winter-spring seasons, and in this time the Kuroshio front meanders with periods shorter than 20 days tended to diminish. Mechanisms that form the persistent deep countercurrents in the central and northern slope areas are discussed in relation to the inverse energy cascade and the Kuroshio separation fro n the continental slope, respectively.

先前的观察表明，在东方海的连续斜坡上，黑果泥的深处存在。但是，尚未阐明其沿连续斜坡的持久性和空间范围。我们在27-29°N附近的斜坡区域的四个位置进行了2年的停泊电表测量，并观察到了十个速度和水文截面的快照，其中包含2004年11月和2006年11月的深度逆流的速度和水文截面。蜿蜒的人被删除。深处反流的结构之间的中央和北斜率区域之间存在差异，其边界对应于气候平均位置，黑果岛与连续斜率分开。中央斜坡区域深处的位置比北部的斜坡更深。 The deep countercurrent had a clear season-fixed nature especially in the central slope area, i.e., periodic countercurrents that vary with periods of 1-2 months were organized into a persistent countercurrent in winter-spring seasons, and in this time the Kuroshio front menders with periods shorter than 20 days tended to diminish.讨论了中央和北坡区域中持续的深层反流的机制，分别与逆向能级联和黑鲁希奥分离有关。