水科学进展2016，Vol.27Issue(1)：57-69,13.DOI:10.14042/j.cnki.32.1309.2016.01.007
长江口枯季北港淡水向北支扩展的动力机制
Dynamic mechanism of freshwater extension from the north channel to the north branch in the Changjiang Estuary in dry seasons
摘要
Abstract
According to the field data collected in the Changjiang Estuary in December 2011 and January 2012, there was a freshwater extension from the North Channel ( NC) to the mouth and lower reaches of the North Branch ( NB) where the water salinity was decreased during spring and the subsequent middle tides. However, the phenomenon was absent during the neap tides and subsequent middle tides. To reveal the origin of the freshwater in the lower reaches of the NB, We employed the well validated 3-D numerical model to reproduce the observed phenomenon. The numerical experiments were conducted and the freshwater flux decomposing method was used to investigate the underlying dy-namic mechanism of the freshwater extension. We found that the freshwater in the NC extends to the NB mainly through its northern outlet ( NONC) and neighboring shoals during spring and the subsequent middle tides due to the Lagrangian transports. Deepening of NONC facilitated the freshwater extension, and hindered the saltwater intrusion into the NB. In the contrast, the high-speed northerly winds would restrict the freshwater extension, while assist the saltwater intrusion into the NB.关键词
盐水入侵/淡水通量/数值模式/长江口Key words
saltwater intrusion/freshwater transport/numerical model/Changjiang Estuary分类
海洋学引用本文复制引用
李路,朱建荣..长江口枯季北港淡水向北支扩展的动力机制[J].水科学进展,2016,27(1):57-69,13.基金项目
国家自然科学基金资助项目(41476077) （41476077）
上海市科学技术委员会重点项目(14231200402) The study is financially supported by the National Natural Science Foundation of China (No. 41476077) . （14231200402）
