山东半岛北及东沿海域冬季的逆温跃层及其与深底层逆流的关系

引用《渤海、黄海、东海海洋图集－水文》分册中有关逆温跃层分布变化图幅以及海流和温、盐度历史资料,指出山东半岛北及东沿岸区域冬季出现的逆温跃层现象与这里冬季潜伏于深底层暖流水有密切关系,半进一步认为围绕山东半岛北及东沿岸海域冬季的海水交换可能呈２层模式,在上层,低温,低盐的沿岸水自西向东南下;在深底层,相对高温、高盐的逆流水北上自东向西有直逼渤海海峡南部的势头。     

山东半岛北及东沿岸海域冬季的逆温跃层及其与深底层逆流的关系

引用《渤海、黄海、东海海洋图集——水文》分册中有关逆温跃层分布变化图幅以及海流和温、盐度历史资料 ,指出山东半岛北及东沿岸区域冬季出现的逆温跃层现象与这里冬季潜伏于深底层暖流水有密切关系 ,并进一步认为围绕山东半岛北及东沿岸海域冬季的海水交换可能呈 2层模式 :在上层 ,低温、低盐的沿岸水自西向东南下 ;在深底层 ,相对高温、高盐的逆流水北上自东向西有直逼渤海海峡南部的势头。     

南黄海西部2007年4月的逆温跃层

利用南黄海西部2007-04的温盐实测资料,采用海洋层结谱表达法及自适应识别,得到逆温跃层的"五点三要素",形成强度要素平面分布图.分析表明,逆温跃层的存在与黄海暖流水有直接的关系:1)4月份,黄海暖流水受到的海面冷却仍是产生逆温跃层的普遍原因,在该海区黄海暖流向北延伸和向两侧拓展的区域都有该种类型的逆温跃层存在,位置相对较浅;2)但在偏南的黄海暖流主干区,海面冷却产生的效应被主流区的热量补充所抵消,逆温跃层很弱甚至消失,这是该月份逆温跃层分布区向北退缩并在南部中心附近呈现缺失区的主要原因;3)南下的鲁北沿岸流水的冷水叠加在黄海暖流水的暖水上方,使逆温跃层加强,使得冷暖水的作用区成为强逆温跃层区;4)黄海暖流左侧冷沿岸流水及右侧冷水的前端向黄海暖流楔入,其前端往往覆盖在底层高温高盐的黄海暖流水上方形成下逆温跃层,从而形成双逆温跃层.这些特点,较以前认知更加客观、全面、细致和准确.     

冬季南黄海海水化学要素的分布特征及变化趋势

通过分析2007年1月12日—2月4日南黄海调查所得资料,对海水化学要素的分布特征及变化趋势进行了研究。结果表明:1)在大部分海域,表、底层海水化学要素分布基本呈现上下均匀状态,这是冬季强烈的垂直混合作用的结果,同时黄海西部沿岸流、台湾暖流前缘水、东海北部的气旋式涡旋和黄海暖流也对各要素的分布发挥着重要的影响。2)调查海域中北部122°30′～124°00′E,34°42′～36°42′N范围内,底层黄海暖流的增温增盐效应较强,且水体垂直混合作用并未到达海底,近底层有跃层存在,使底层水既保留了夏季黄海冷水团水的特性,同时又由于黄海暖流的入侵而具有暖水的性质,跃层和夏季冷水团残留水为溶解氧(DO)和pH低值区的产生以及营养盐高值区的出现提供了良好的水文条件或动力因素。生物化学作用则是形成上述现象的内在原因,而且该跃层也阻碍了各生源要素的垂向输运,使底层水与底层以上水体具有明显不同的生化性质。3)冬季南黄海各化学要素除具有垂直均匀分布的特点外,在中北部各断面东侧还存在层化现象或锋面结构,表现为上层的垂直均匀分布和下层的梯度分布,这也是该海域近底层水体层化以及黄海暖流较强的增温增盐效应所致。     

长江口及济州岛邻近海域温、盐、密度的跃层现象

本文根据CTD观测资料,分析了研究海区的温、盐、密度跃层的分布与变化,讨论了逆温逆盐层的分布区域,并从跃层角度出发,分析了深层水的涌升,黄海冷水团的上边界以及台湾暖流在东海北部的影响范围。     

黄、东海地理环境与环流系统分析——长江口及济州岛邻近海域综合调查研究报告(第二章)

简要介绍了黄海和东海的地理环境概况,着重分析调查海域的环流系统。有如下一些初步看法与结论。 台湾暖流的前缘混合水,可从长江冲淡水底层穿越而影响到苏北沿岸,直到32°N以北的浅水区域。对马暖流西侧的水体是东海混合水,而其东侧为黑潮分支。黄海暖流的流向在不同季节具有规律的摆动。黄海底层冷水团属于季节性水团,其强盛及消衰与温跃层的形成及消亡紧密相关。黄海底层冷水团与中部底层冷水并非每年彼此独立,它们的共同特征甚至比其差异更明显。夏季东海冷水不能借助爬升侵入黄海底层冷水团内部。在济州岛南部区域,中层的逆温、逆盐现象,是由黄海密度环流的扩散效应与东海冷水沿黄海底层冷水团边界的爬升这两个原因而形成的。     

东海北部底层冷水及双跃层初析

本文着重探讨东海北部区域底层冷水的形成和季节变化过程,指出北部冷水系冬季黄海沿岸水南下向东海输送低温水,并与外海高盐水混合变性形成的,它具有明显的移动规律。阐述了黄海沿岸水沿陆架下沉与黑潮次-中层水爬升的关系及其对北部冷水的影响。本文还分析了济州岛南部区域双跃层现象的类型及其波状结构的成因。发现上,下跃层之间存在着“跃层间环流”,它将导致双扩散的发生和有利于双跃层的维持。     

秋季南黄海西部营养盐的分布及其与环流场的关系

重点分析和研究了秋季南黄海西部营养盐的分布状况和水文特征,并在此基础上探讨了营养盐分布及其运移规律与该海域环流场的关系.结果表明:长江冲淡水、苏北沿岸水以及鲁北沿岸水所引起的物质输入是导致南黄海西部近岸海域三个营养盐含量高值区形成的主要因素;由于跃层阻隔以及底层有机物的氧化分解,调查海域中部底层水体也存在较大面积的营养...     

长江口、济州岛海域温、盐分布探讨

分析了长江口及济州岛以南海域温盐分布特征,指出黄海沿岸水在向南运动过程与外海水混合变性的某些规律;指出表层长江冲淡水影响的厚度及范围;阐述了黄海低温低盐水与黑潮高温高盐水的侧向相互作用,在济州岛南部海域形成了多跃层结构和逆盐逆温现象,并对整个调查海区的跃层现象进行了分类和分析。此外还分析了黄海沿岸水下沉与黑潮次—中层水爬升对东海北部底层冷水的影响。     

东海西北部中层冷水的成因

根据1959—1996年4—6月存在中层冷水的28°～30.5°N,124°E以西海域的温、盐、密度资料,对中层冷水的特征,深度与盐、密度跃层的配置及中层冷水的存在和发展与表层热含量和底层盐含量间的关系进行了分析。指出:中层冷水是存在于密跃层之中,高密度(台湾暖流)水的浮力效应使其叠置于它的上方;在春季,表层热含量和表征台湾暖流的底层盐含量的同步提加,提高了密度跃层的强度,是中层冷水得以维持的重要因素。中层冷水核心的温度与其对应冬季表层温度间的相关分析及三维流场的数值模拟结果揭示,研究海区中层冷水的来源为:(1)当地冬季表层水(南下黄海表层水与东海表层水的混合水)冷却对流;(2)几种水组成的浙闽沿岸水于冬季下沉和向东伸展。     

Review on current and seawater volume transport through the Taiwan Strait

Patterns and features of currents and seawater volume transports in the Taiwan Strait have been reviewed by examining the results from more than 150 research papers in recent decades. It is noted that there are diverse or even conflicting viewpoints on these subjects. Here both common and different opinions are summarized. This review paper covers the studies involving in situ measurements and numerical modeling of current velocity, analyses of hydrographic data, and classification of water masses. Generally speaking, there are three currents in the Taiwan Strait: the China Coastal Current along the Fujian coast in the western Taiwan Strait, the extension of the South China Sea Warm Current in the western and central Taiwan Strait, and the Kuroshio’s branch or loop current intruding through the eastern Taiwan Strait. The current pattern in winter is quite different from that in summer, and the currents also exhibit differences between the upper and lower layers. The seawater volume transport through the Taiwan Strait is about 2.3 Sv northward in summer but about 0.8 Sv northward in winter. Both the current pattern and the seawater transport vary with local winds in the Taiwan Strait. This is particularly true in winter when the currents and the transport in the upper layer are significantly affected by strong northeasterly winds.     

Study on abundance variation of pteropods in the East China Sea

1 Introduction Pteropoda, an order of marine pelagic mollusks, belongstoClassGastropoda,SubclassOpisthobranchia. The speciesofthisorder can be found all over the world buttheyareusuallyabundantinthecontinentalshelfand continental slope area. As fish diets…     

东海西部陆架海域水团的季节特征分析

On the basis of the CTD data and the modeling results in the winter and summer of 2009, the seasonal characteristics of the water masses in the western East China Sea shelf area were analyzed using a cluster analysis method. The results show that the distributions and temperature-salinity characteristics of the water masses in the study area are of distinct seasonal difference. In the western East China Sea shelf area, there are three water masses during winter, i.e., continental coastal water（CCW）, Taiwan Warm Current surface water（TWCSW） and Yellow Sea mixing water（YSMW）, but four ones during summer, i.e., the CCW, the TWCSW, Taiwan Warm Current deep water（TWCDW） and the YSMW. Of all, the CCW, the TWCSW and the TWCDW are all dominant water masses. The CCW, primarily characterized by a low salinity, has lower temperature, higher salinity and smaller spatial extent in winter than in summer. The TWCSW is warmer, fresher and smaller in summer than in winter, and it originates mostly from the Kuroshio surface water（KSW） northeast of Taiwan, China and less from the Taiwan Strait water during winter, but it consists of the strait water and the KSW during summer. The TWCDW is characterized by a low temperature and a high salinity, and originates completely in the Kuroshio subsurface water northeast of Taiwan.     

Characteristics of water mass under the surface mixed layer in Tsushima Straits and the southwestern Japan Sea in autumn

Two different cold waters were found under the surface mixed layer in Tsushima Straits and the southwestern Japan Sea in autumn 2004. One is cold saline water with a low concentration of dissolved oxygen, and the other is cold less saline water with a high concentration of dissolved oxygen. The older saline water originates from the bottom of the East China Sea, strongly influenced by the Kuroshio water with high salinity. The bottom density in the eastern channel of the Tsushima Straits is coincident with that of the East China Sea in autumn, corresponding to the season when the cold saline water was frequently found in the Tsushima Straits. The newer less saline water originates from the front of Tsushima Warm Current between the Tsushima Warm Current water and the surface cold water in the Japan Sea. This water is formed by subduction above the isopycnal surface from the front of the Tsushima Warm Current.     

The Formation and Circulation of the Intermediate Water in the Japan Sea

In order to clarify the formation and circulation of the Japan/East Sea Intermediate Water (JESIW) and the Upper portion of the Japan Sea Proper Water (UJSPW), numerical experiments have been carried out using a 3-D ocean circulation model. The UJSPW is formed in the region southeast off Vladivostok between 41°N and 42°N west of 136°E. Taking the coastal orography near Vladivostok into account, the formation of the UJSPW results from the deep water convection in winter which is generated by the orchestration of fresh water supplied from the Amur River and saline water from the Tsushima Warm Current under very cold conditions. The UJSPW formed is advected by the current at depth near the bottom of the convection and penetrates into the layer below the JESIW. The origin of the JESIW is the low salinity coastal water along the Russian coast originated by the fresh water from the Amur River. The coastal low salinity water is advected by the current system in the northwestern Japan Sea and penetrates into the subsurface below the Tsushima Warm Current region forming a subsurface salinity minimum layer. This revised version was published online in August 2006 with corrections to the Cover Date.     

对马暖流“东海段”的流路与流速

本文全面地分析了此段海流的流路与流速结构，首次提出研究海域近底层的环流示意图。指出在夏季，韩国南岸和日本九州北岸均存在着一支南下的逆流，九州西岸出现两种或多种形式的流路。对马暖流在源地流速很弱，流向不稳定，流路时隐时显不明显，只有离开源地后才逐渐显示出一支海流轮廓；强流区在朝鲜海峡附近。该海流可明显地划分为三段。流速夏强冬弱，夏季流幅宽约８０ｋｍ。