摘要
长江冲淡水向外海扩展对于黄、东海水文生物环境以及物质循环有重大影响。通过分析1998-2014年连续17年卫星观测结果,研究夏季长江冲淡水向外海扩展的年际间变化规律,分析径流量和风场对其变化的影响。结果显示,夏季长江冲淡水向外海的扩展路径主要有东北偏北型、东北型和偶见型三类,以东北型为主;冲淡水向东扩展位置主要分布在123°-126°E区间,年际间差异显著。扩展过程的年际变化主要体现在扩展路径是否转向、向东扩展的态势呈现7弱8强还是7盛8衰。长江径流量的多寡对冲淡水向外海扩展的远近起到重要影响作用,径流量较大时,冲淡水向东扩展较远,径流量较小时,冲淡水向东扩展的距离会受到明显的限制。风向的变化是导致冲淡水扩展过程呈现多样性的一个重要原因。东南风、东风对于冲淡水向东北方向扩展起到促进作用,对于向东南方向扩展起到一定的阻碍作用,东北风对冲淡水向外海的扩展起到阻碍作用,迫使冲淡水盘踞在长江口近岸海域。
Expansion of the Changjiang Diluted Water(CDW)to the outer sea has a significant impact on the hydrobiological environment and material cycle in the Yellow Sea and the East China Sea.Based on 17 years of satellite fusion data from 1998 to 2014,this paper studies the inter-annual variations of the CDW spreading to the outer sea in summer,analyzes the influences of runoff and wind field on these changes.The result shows that the expansion path is mainly divided into three types:northeast-north type,northeast type and occasional type,in which northeast type is in the majority.The eastern boundary of the CDW expansion appears obviously inter-annual variations,and it mainly distributes in the range of 123°E to 126°E.The inter-annual variation of the expansion process is mainly reflected in the changes of expansion path and the distance of eastern expansion from July to August.The amount of runoff plays an important role in the distance of CDW expansion to the outer sea.When the runoff is large,the diluted water expands farther eastward,while when the runoff is small,the diluted water is limited near the Yangtze River estuary.The diversity of expansion process is obviously affected by wind direction.Southeast wind and east wind promote the expansion of diluted water in the northeast direction,and prevent the expansion in the southeast direction to some extent.Northeast wind prevents the expansion to the outer sea,forcing the diluted water staying near the Yangtze River estuary.
作者
胡静雯
王其翔
郭志谦
刘晓燕
吴志宏
董文隆
田林
HU Jingwen;WANG Qixiang;GUO Zhiqian;LIU Xiaoyan;WU Zhihong;DONG Wenlong;TIAN Lin(Weifang Key Laboratory of Satellite Remote Sensing Intelligent Interpretation Technology,Weifang 261021;Shandong Marine Forecast and Hazard Mitigation Service,Qingdao 266000;Shandong Provincial NO.4 Institute of Geological and Mineral Survey,Weifang 261021;Institute of Oceanographic Instrumentation,Qilu University of Technology(Shandong Academy of Sciences),Qingdao 266000;National Satellite Meteorological Center,Beijing 100081)
出处
《空间科学学报》
CAS
CSCD
北大核心
2023年第6期1069-1080,共12页
Chinese Journal of Space Science
基金
潍坊市卫星遥感智能解译技术重点实验室开放基金资助(SYS202303)。
关键词
空间遥感
长江冲淡水
年际变化
Remote sensing data
Changjiang diluted water
Interannual variation
作者简介
胡静雯,E-mail:hujingwen@shandong.cn;通信作者:田林,E-mail:tianl@cma.gov.cn。
