摘要
使用SODA表层盐度月平均数据,通过计算逐点逐年盐度均值、月际差,绘制等值线分布图,分析在新的30年气候基准期(1981—2010年),东海及毗邻的西北太平洋海域表层盐度场气候态分布特征,为进一步研究该地区长时间序列的气候变化奠定基础。结果表明:(1)在研究区表层平均盐度从西北到东南逐渐升高,形成3个明显的盐度特征场区:东海大陆架海区、东海黑潮海区以及西北太平洋海区;(2)研究区月际表层盐度存在明显的周期性变化,其中,盐度最小值的周期性规律最显著;(3)在月际变化中,1—4月为盐度高值季节,以3月份盐度最高,为27.5psu;5—8月为盐度低值季节,以8月份盐度最低,为22psu;9—12月为盐度上升季节;(4)依据盐度场的分布,结合地形、气候、海流等特征和前人研究,在研究区选取了22个特征点,从特征点看,位于西北太平洋海区的特征点盐度月振幅最小;位于长江入海口附近的D1和位于杭州湾南部的D2盐度月振幅较大,但D1与D2月际变化曲线呈现较为明显的反相关特征,这可能与长江冲淡水水舌夏季北移抑制苏北沿岸流南下和北上的台湾暖流夏强冬弱有关。
Counter maps of the East China Sea and the adjacent northwest Pacific Ocean are compiled and analyzed based on the annual mean data,monthly average data,monthly difference and inter-monthly difference data of SODA surface salinity for the past 30-year climate reference period(1981-2010).The climatic distribution patterns of the surface salinity field in the Pacific Ocean have provided a solid foundation for further study of the long-term climate changes in the region.As it is observed that:(1)The average surface salinity in the study area gradually increase from northwest to southeast,with three distinct salinity subareas:the area of the East China Sea continental shelf,the part of East China Sea where the Kuroshio current passes through and the area of Northwest Pacific Ocean;(2)There is a significant cyclical change in the salinity of surface water in the study area,among which the periodicity of the minimum salinity is the most significant;(3)In terms of monthly changes,high salinity appears in January-April,with a highest of 27.5 psu in March,while the low salinity in MayAugust,with a lowest of 22 psu in August,;The season from Sept-Dec is the period of salinity rising;(4)According to the salinity distribution patterns and their relation with topography,climate and sea currents,22 points for reference are selected.The lowest reference points of monthly salinity mostly occur in the northwestern Pacific Ocean;Highest amplitude is observed at D1 near the Yangtze River estuary and D2 in the south of Hangzhou Bay.However,the monthly correlation curves at D1 and D2 are obviously opposite,probably caused by the northward shifting of dilute water of the Yangtze River in summer,when the southward flow of the north Jiangsu coast current is inhibited by the Taiwan warm current,which is strong in summer and weak in winter.
作者
徐芬
康建成
XU Fen;KANG Jiancheng(Urban Ecology and Environmem Research Center, Department of Geography,Shanghai Normal University , Shanghai 200234,China)
出处
《海洋地质与第四纪地质》
CAS
CSCD
北大核心
2019年第2期44-60,共17页
Marine Geology & Quaternary Geology
基金
国家自然科学基金项目"东海黑潮区温
盐
流
海面高度多尺度变化过程及其机理研究"(41340045)
上海师范大学科研发展项目(KF201824)
关键词
盐度
新气候基准期
表层
东海
西北太平洋
salinity
new climate base period(1981-2010)
sea surface
East China Sea
northwest Pacific