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1.
北黄海温盐分布季节变化特征分析   总被引:9,自引:1,他引:8  
利用2006~2007年夏冬春秋4个季节北黄海的大面调查资料,分析了4个季节北黄海温度和盐度大面以及典型断面分布特征,得出以下结论:2007年冷水团势力范围强于2006年,北黄海冷水团的形成受地形影响.黄海暖流冬春季较强,冬季最强,夏季最弱,秋季开始形成.鲁北沿岸流冬季最强,春季减弱,夏秋季消失,但夏季鲁北沿岸存在冬季鲁北沿岸流水的残余体,即鲁北沿岸水.辽南沿岸水4个季节都以低盐为特征,除夏季低盐中心位于庄河口外,其它3个季节低盐中心均位于调查区域的东北角.渤海与北黄海之间的水交换4个季节都存在.春季,断面盐跃层形成滞后于温跃层;秋季,断面盐跃层消失滞后于温跃层.  相似文献   

2.
基于2006至2007年“908”项目执行期间春夏秋冬共四个航次的CTD温盐数据,针对四个季节底层大面及大连一成山头断面温度和盐度的分布特征,分析了北黄海冷水团的季节变化,初步探讨了其消长过程,并与历史资料相比较,发现了关于北黄海冷水团的新问题。研究表明:夏季,北黄海冷水团温度和盐度与历史资料相比,低温中心位置存在东偏,但低温中心温度和盐度变化不大。春季,32.8psu高盐水舌主轴位置较冬季偏西约75km,123.5°E以东的原冬季盐度高值区的范围向北延伸的势力大减,退化为较弱的小高盐水舌冬。冬季,北黄海冷水团已经消失,黄海暖流呈舌状向北延伸。秋季,减弱的北黄海冷水团存在两个中心温度约9℃的低温中心。  相似文献   

3.
北黄海冷水团季节变化特征分析   总被引:3,自引:0,他引:3  
利用2006—2007年春、夏、秋、冬4个航次的CTD数据,对北黄海冷水团的季节变化及其消长过程进行了分析.结果显示:春季,冷水团特征开始出现,6℃冷水占据了调查区域的1/3,冷水团中心的盐度值大于32 psu.成山头以东的高盐水舌主轴从冬季的124°E西移至123.3°E处;夏季,北黄海冷水团特征最为明显,核心温度约6℃,盐度高于32 psu,盘踞在50 m等深线以深的深槽中,温、盐呈现明显的双峰结构.与前人的结果相比,本文低温中心的位置偏东;秋季,北黄海冷水团强度减弱,但仍存在2个低温中心,并且高盐中心位于38.5°N,122.5°E附近;在垂直方向上,冷水团与上层水之间以温跃层为分界:温跃层春季时形成,位于20~30m;夏季达到最强,跃层在10~20m;秋季减弱,跃层深度降至30~40m;至冬季温跃层完全消失.  相似文献   

4.
黄海暖流源区海表面温度锋面的结构及季节内演变   总被引:2,自引:0,他引:2       下载免费PDF全文
刘传玉  王凡 《海洋科学》2009,33(7):87-93
利用1985~2002年月均和每8天平均的AVHRR Pathfinder卫星海表面温度数据,分析了黄海暖流源区海表面温度锋面的分布特征及其季节和季节内演变过程的规律.分析结果表明,黄海暖流源区海表面温度锋面只在冬季及其前后出现,且是一个包含南北两支锋面的锋面系统,其北支锋面位于33°~34°N之间,大体呈东西走向,南支锋面沿长江浅滩边缘,呈西北东南走向,作者称之为黄海暖流源区锋面.该锋面从11月下旬于济州岛西部生成并向西北方向扩展,至1,2月份达到最大程度,于2月下旬后向东南方向退缩并在3月份至5月份之间消失.在该锋面系统的生长期和衰退期,其南北两支锋面有时于西端连接在一起而形成指向西北的舌状锋面.黄海暖流源区锋面的演变过程与黄海暖流的演变过程紧密相关,也对黄东海的质量和热量交换有重要影响.  相似文献   

5.
冬季南黄海海水化学要素的分布特征及变化趋势   总被引:5,自引:0,他引:5       下载免费PDF全文
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。  相似文献   

6.
南黄海暖流水附近冷水块的分析研究   总被引:1,自引:0,他引:1  
在南黄海东南部,呈现高温、高盐特征的南黄海暖流水(以下简称暖流水)终年入侵。冬半年,暖流水自济州岛东南沿西北方向大量涌入南黄海,并盘踞其大部海区,因此,该海域水文要素场(温度、盐度、密度)等值线的分布大多呈舌形。但在济州岛西北,朝鲜半岛西南海域外的水文状况则呈现低温、高盐特征。夏半年,黄海冷水团与南黄海沿岸流强盛,暖流水势力锐减,南黄海温、盐度等值线的分布不再大片地呈现明显舌形,舌状分布仅出现在34°N以南,124°E以东海区。此时,在暖流水附近,济州海峡西北部,朝鲜半岛西南海岸外,经常出现一个具有高盐特性的冷水块。此冷水块的出现与南黄海暖流水的变异有关,并且存在时间较长,因此,其温、盐性质构成了南黄海水文特征的一部分。本文试图分析研究这一冷水块的基本水文特征并对其成因提出初步看法。 本文主要引用1976-1979年在南黄海海域调查的部分观测资料以及朝鲜1934-1938年的近海观测资料。  相似文献   

7.
南黄海环流的若干特征   总被引:47,自引:7,他引:40  
主要根据近几年来中韩黄海水循环动力学合作调查结果,结合有关历史资料,对南黄海环流的若干特征进行了分析。所得主要认识为:(1)南黄海环流存在明显的季节变异。冬、夏季环流的基本形态有着较大的差别。(2)黄海暖流的路径和强度均有一定的年际变化。分析显示,1997年冬季,暖流路径明显偏于槽的西侧;而1986年冬,暖流的主流路径则沿槽北上。(3)黄海暖流并非对马暖流的直接分支。黄海暖流水是对马暖流水和陆架水混合而成。而且,它主要是在济州岛西侧海域,从锋区中衍生出来的。(4)夏季黄海表、底层环流大致皆是由一大的道时针向流系构成。但在其表层海盐尺度的气旋式环流内部还存在小的气旋和反气旋流环。分析亦表明,不论表层或底层,皆无高盐暖水从济州岛邻近海域进入黄海东部的明显迹象。  相似文献   

8.
由黑潮派生的各种暖流对东海而言是重要的热能来源,它们的态势会极大地影响东海的温度分布,从而影响到生态系统的变化和发展.通过对2003年度东海暖流主干温度、暖舌前锋位置进行空间分析,并与历史状况比较,结果表明在2003年春夏黑潮和对马暖流的温度和势力与常年差不多,台湾暖流及黄海暖流比常年要弱一些;夏初各暖流都出现了较大幅度低于常年的状况,先是黑潮,然后台湾暖流、对马暖流最后是黄海暖流.而秋冬两季除黄海暖流只比常年略强一些外,各暖流均呈强势,不但温度较高,而且暖舌的伸展距离比常年有不同程度增加.特别是黑潮、台湾暖流和对马暖流在冬季都接近历史最强水平,而相对较弱的黄海暖流也比多年平均略强一些.  相似文献   

9.
研究北黄海北部近岸海域浮游植物群落结构季节变化及其与环境因子之间的关系。2008年5月(春季)-2009年2月(冬季)在北黄海北部近岸海域(39.5°~39.8°N、123.0°~123.45°E)进行4个季节海上浮游植物调查,共鉴定出浮游植物80种,4季共有种类10种。调查海域优势种类较多,优势种类季节变化明显,夜光藻(Noctiluca scientillans)、伏氏海线藻(Thalassionema frauenfeldii)和丹麦细柱藻(Leptocylindrus danicus)分别是季节第一优势种。全年浮游植物细胞丰度平均为54279.3×104/m3,呈现典型的交叉双峰模式,夏冬季明显高于春秋季,春季是细胞丰度最小的季节。多样性指数H′均值为2.4941,表现为秋季冬季春季夏季;均匀度指数均值为0.640 8,表现为秋季春季冬季夏季。营养盐结构分析显示春夏季表现为潜在P限制,秋冬季表现为潜在N限制,N:P是决定优势群落种类的关键因素之一。冗余分析(RDA)分析结果表明,盐度(S)、悬浮物(SS)、磷酸盐(DIP)和无机氮(DIN)是影响浮游植物种类组成和丰度的关键环境因子。  相似文献   

10.
冬季黄海暖流西偏机理数值探讨   总被引:1,自引:0,他引:1  
利用海洋数值模式(MITgcm)模拟了冬季黄海流场并对冬季黄海暖流西偏的机理进行了探讨。冬季黄海流场模拟试验表明,黄海暖流由济州岛以西约32.5°N,125°E附近进入黄海,然后沿着黄海深槽西侧70 m等深线附近向北偏西运动;海面高度调整对黄海暖流路径具有重要影响,沿着黄海暖流路径的海面高度梯度比周围海区大,由海面高度梯度产生的地转流引起的北向体积输运占总的北向体积输运的78%。狭长海湾地形控制试验表明,单纯的黄海地形分布不足以引起黄海暖流西偏。黄海典型断面试验与渤海、黄海、东海地形控制试验说明,黄海暖流进入黄海的地理位置对流场分布有重要影响,黄海暖流进入黄海的位置恰好位于深槽西侧地形坡度较大区域,在位涡守恒的约束下黄海暖流受地形捕获沿70 m等深线附近向北偏西运动;试验还表明,黄海暖流进入黄海的位置与东海北部环流和地形分布有关,在冬季风的作用下东海北部环流的一部分沿着地形陡坡进入黄海形成黄海暖流。由此认为,黄海、东海环流在其特殊地形的约束下对冬季风的响应和调整,是引起黄海暖流西偏的主要原因。  相似文献   

11.
Recent advances in ocean-circulation research on the Yellow Sea and East China Sea shelves are summarized. Observations using acoustic Doppler current profilers (ADCPs) suggest that the connectivity of mean-volume-transports is incomplete between the Tsushima (2.6 Sverdrups; 1 Sv = 106 m3/s) and Taiwan Straits (1.2 Sv). The remaining 1.4-Sv transport must be supplied by onshore Kuroshio intrusion across the East China Sea shelf break. The Yellow Sea Warm Current is not a persistent ocean current, but an episodic event forced by northerly winter monsoon winds. Nevertheless, the Cheju Warm Current is detected clearly regardless of season. In addition, the throughflow in the Taiwan Strait may be episodic in winter when northeasterly winds prevail. The throughflow strengthens (vanishes) under moderate (severe) northeasterly wind conditions. Using all published ADCP-derived estimates, the throughflow transport (V) in the Taiwan Strait is approximated as
where V 0, V 1, K are 1.2 Sv, 1.3 Sv, and 157 days, respectively, t is yearday, and T is 365.2422 days (i.e., 1 year). The difference between the throughflow transports in the Tsushima and Taiwan Straits suggests that the onshore Kuroshio intrusion across the shelf break increases from autumn to winter. The China Coastal Current has been observed in winter, but shelf currents are obscure in summer.  相似文献   

12.
Using our data from special observation in the source area of the Taiwan Warm Current from 19S2 to 1985) and historical data, the authors conducted studies to clarify the temperature and salinity characteristics, variability, and origin of the Taiwan Warm Current Water, and its influence on the expanding direction of the Changjiang Diluted Water.The main results of these studies are briefly given below. (1) The Taiwan Warm Current Water can be divided into two parts:the Surface Water of the Taiwan Warm Current and the Deep Water of the Taiwan Warm Current; the former is formed due to the mixing of the Kuroshio Surface Water flowing northward along the east coast of Taiwan with the Taiwan Strait Water; the latter completed originates from Kuroshio Subsurface Water to the east of Taiwan. It is characterized by lower temperature and higher salinity in summer and the characteristics of temperature and salinity are more stable. The maximum seasonal variational range and maximum secular variational range of t  相似文献   

13.
Winter counter-wind currents off the southeastern China coast: A review   总被引:11,自引:1,他引:11  
This review covers the discovery and studies of the year-round northeastward currents off the southeastern China coast, paying special attention to its upwind characteristic in winter, mainly focusing on work by Chinese oceanographers. This current system is a prominent and unique phenomenon in the shelf circulation of the world ocean. The general features of the current system are summarized. The evidence for the existence and the variation of the three parts of the currents—the South China Sea Warm Current, the Taiwan Strait Warm Current and the Taiwan Warm Current—are separately elucidated. The formation mechanisms of the current as a whole are explained using dynamic analysis and numerical simulation results. Some suggestions for further studies are also made.  相似文献   

14.
渤海、黄海、东海冬季海流场温度场数值模拟和同化技术   总被引:6,自引:0,他引:6  
利用NASA高分辨率的卫星遥感资料SST,采用Nudging同化来模拟渤海、黄海、东海的三维温度场,减小用热通量作上边界条件所带来的误差.结果表明,模拟的海流场能较好地反映渤海、黄海、东海的环流特征.数据同化后的温度场优于未经同化的温度场.3个选择站点的同化值与实测值的均方根误差分别为1.307,0.526,0.744,用热通量资料模拟的水温与实测值的均方根误差分别为2.160,0.979,1.330.尽管只同化了海表温度,但数据同化对三维温度场结构都有影响.  相似文献   

15.
本文分析该海域约70个测站的温、盐资料,获得以下结果:(1)夏季在对马暖流的源区,于10~75m水层内,其流路成一明显的分界线,左(西)侧温、盐度较低,右(东)侧温、盐度较高。(2)夏季对马暖流源区存在着三种海水:高温、高盐水,高温、低盐水和高温、次高盐水。(3)夏季朝鲜海峡地区,东水道的温、盐度高于西水道温、盐度。(4)1987年,东海黑潮区、长江口、杭州湾外及东海酉南部海域,夏季的表层盖度,皆比1989年同季、同一海域的盐度偏高;而对马暖流“东海段”却出现相反的低盐现象。其原因之一,1987年冲淡水势力极强,几乎盘踞了对马暖流源区的大部分海域,使源区盐度下降,并随对马暖流北上输送的缘故。其中:(1)和(4)两点认识系首次提出。  相似文献   

16.
本文对出现在海南岛以东外海的暖涡及其形成机制作了简略的回顾及分析,认为这个暖涡是常常出现在这区域的,其存在与南海北部的西向流在遇到陆架—陆坡海域作反气旋式偏转而延伸为南海暖流有关;同时当南海暖流流向东北作反气旋式弯曲时,在暖流右侧也会出现暖涡。暖涡冬季较弱,夏季当海南岛东岸在西南风作用下出现上升流时会得到加强。  相似文献   

17.
Seasonal Variation of the Cheju Warm Current in the Northern East China Sea   总被引:1,自引:1,他引:1  
The Cheju Warm Current has been defined as a mean current that rounds Cheju-do clockwise, transporting warm and saline water to the western coastal area of Cheju-do and into the Cheju Strait in the northern East China Sea (Lie et al., 1998). Seasonal variation of the Cheju Warm Current and its relevant hydrographic structures were examined by analyzing CTD data and trajectories of satellite-tracked drifters. Analysis of a combined data set of CTD and drifters confirms the year-round existence of the Cheju Warm Current west of Cheju-do and in the Cheju Strait, with current speeds of 5 to 40 cm/s. Saline waters transported by the Cheju Warm Current are classified Cheju Warm Current water for water of salinity greater than 34.0 psu and modified Cheju Warm Current for water having salinity of 33.5–34.0 psu. In winter, Cheju Warm Current water appears in a relatively large area west of Cheju-do, bounded by a strong thermohaline front formed in a "" shape. In summer and autumn, the Cheju Warm Current water appears only in the lower layer, retreating to the western coastal area of Cheju-do in summer and to the eastern coastal area sometimes in autumn. The Cheju Warm Current is found to flow in the western channel of the Korea/Tsushima Strait after passing through the Cheju Strait, contributing significantly to the Tsushima Warm Current.  相似文献   

18.
关于台湾暖流水的研究   总被引:1,自引:0,他引:1  
本文根据专题调查和历史资料,分析了台湾暖流水的温、盐特性,来源,变化特征以及对长江冲淡水的影响。  相似文献   

19.
Using a temperature data set from 1961 to 1990, we estimated the monthly distribution of the vertically integrated heat content in the East China Sea. We then drew the monthly map of the horizontal heat transport, which is obtained as the difference between the vertically integrated heat content and the surface heat flux. We anticipate that its distribution pattern is determined mainly due to the advection by the ocean current if it exists stably in the East China Sea. The monthly map of the horizontal heat transport showed the existence of the Taiwan-Tsushima Warm Current System (TTWCS) at least from April to August. The T-S (temperature-salinity) analysis along the path of TTWCS indicated that the TTWCS changes its T-S property as it flows in the East China Sea forming the Tsushima Warm Current water. The end members of the Tsushima Warm Current water detected in this study are water masses in the Taiwan Strait and the Kuroshio surface layer, the fresh water from the mainland of China, and the southern tip of the Yellow Sea Cold Water extending in the northern part of the East China Sea. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

20.
By using Acoustic Doppler Current Profiler (ADCP) measurements with the four round-trips method to remove diurnal/semidiurnal tidal currents, the detailed current structure and volume transport of the Tsushima Warm Current (TWC) along the northwestern Japanese coast in the northeastern Japan Sea were examined in the period September–October 2000. The volume transport of the First Branch of the TWC (FBTWC) east of the Noto Peninsula was estimated as approximately 1.0 Sv (106 m3/s), and the FBTWC continued to flow along the Honshu Island to the south of the Oga Peninsula. To the north of the Oga Peninsula, the Second Branch of Tsushima Warm Current and the eastward current established by the subarctic front were recombined with the FBTWC and the total volume transport increased to 1.9 Sv. The water properties at each ADCP line strongly suggested that most of the upper portion of the TWC with high temperature and low salinity flowed out to the North Pacific as the Tsugaru Warm Current. In the north of the Tsugaru Strait, the volume transport of the northward current was observed to be as almost 1 Sv. However, the component of the TWC water was small (approximately 0.3 Sv).  相似文献   

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