东海黑潮表层盐度分布特征及其影响因素

Surface salinity distribution of the Kuroshio in the East China Sea and its influencing factors

利用美国国家海洋大气管理局2007年发布的全球海域温、盐数据库资料,美国地球物理数据中心2006年发布的海底地形数据库资料以及日本海洋科学与技术机构2003年发布的1997—2002年东海地区月平均降水量资料,研究东海黑潮表层盐度的月季分布特征,并分析其影响因素。结果表明,东海黑潮表层盐度存在明显的月季变化特征。总体而言,12月至次年3月表层盐度高,6—9月表层盐度低,4、5月和10、11月为过渡阶段;表层盐度高值分布在东海黑潮主段靠近东边界一侧;6—9月入口段的表层盐度高于出口段的表层盐度,其他月份入口段的表层盐度低于出口段的表层盐度。东海黑潮表层盐度主要受表层温度、降水、径流的影响。冬、春、秋季的表层盐度分布在黑潮主段靠近陆架一侧区域受表层温度影响大;降水对东海黑潮表层盐度产生局部小范围的影响,时间主要集中在1月和6—8月份,区域分布在低纬25°N以南和30°N附近。长江冲淡水夏季对东海黑潮表层盐度的影响大于其他季节对东海黑潮表层盐度的影响,7月长江径流量达到最大值时,对应的黑潮扇形区的盐度最低。

Using the World Ocean Atlas 2005 by the National Oceanic and Atmospheric（NOAA） published in 2007,topog-raphy database in 2006 by the National Geophysical Data Center（NGDC）,and the grid precipitation data of the Asian region by the Japan Agency for Marine-Earth Science and Technology（JAMSTEC） published in 2003,the authors explore three-dimensional techniques for oceanic data analysis and figures manifestation with Matlab computer programs.They find that the surface salinity distribution of the Kuroshio in the East China Sea（ECS） varies monthly.First,the salinity at surface is higher in December through March,and is lower in June to September;the salinity in the rest of year is in between.Second,the salinity is the highest near the east side of the Kuroshio in the East China Sea where is closer to Ryukyu Island.The salin-ity at surface is affected by surface temperature,rain,and Changjiang diluted water.The salinity at surface of the Kuroshio in the East China Sea is mainly influenced by surface temperature near the shelf of contentious in November to February.Surface salinity is impacted by precipitation at small-scale in January and summer,which is in areas south of 25°N and also near 30°N where the ECS-Kuroshio flows into the Tokara Strait.Summer runoff of Changjiang diluted water affects most to the surface salinity of the Kushiro in a fan-shaped zone,resulting the maximum runoff in July and the corresponding minimum salinity on surface of the Kuroshio in the fan-shaped zone in the East China Sea.