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1.
用水文化学要素聚类分析台湾海峡西部水团   总被引:1,自引:3,他引:1  
本文根据Helland-Hansen创立的浓度混合理论[1,2],在稀释混合过程中,把盐度作为保守性要素,通过相关分析,选出与盐度之间存在显着相关的水文水化要素,采用Q型多维聚类分析。聚合归类结果表明,台湾海峡西部水团主要有闽浙沿岸水,粤东沿岸水,闽江、九龙江、韩江冲淡水,台湾海峡混合水,内斜上升冷暖水,粤东上升流。春、夏季台湾海峡混合水是由黑潮分支、南海表层水、闽浙沿岸水、粤东沿岸水交错混合所成。秋、冬季台湾海峡混合水是由黑潮分支、东海陆架水、闽浙沿岸水、粤东沿岸水交错混合所组成。各水团明显表现出季节性的消长变化。  相似文献   

2.
阿拉伯上升流温度锋面时空分布特征分析   总被引:1,自引:0,他引:1  
阿拉伯上升流区域水文环境复杂,地理位置重要,研究该海区的水文特征具有重要的意义。基于WOA13数据,利用绝对梯度最大值法提取了锋面的锋轴线,简要分析阿拉伯上升流海区的温度锋的时空分布特征和强度分布特征。结果表明,阿拉伯上升流锋主要存在于春夏两季,沿阿拉伯半岛东海岸线分布,存在于13°N~19°N之间,随深增加锋轴线逐渐远离海岸。水平上锋强度较大地区位于夏季的13°N~16°N和19°N附近,垂直方向上锋强度较大地区位于40~100 m之间。  相似文献   

3.
台湾海峡西南部海域春季悬浮体及沉积物来源与输运机制   总被引:2,自引:2,他引:0  
台湾海峡作为连接东海和南海的重要通道,其悬浮体和沉积物的来源和输运格局非常复杂。2005年4~5月利用带有浊度传感器和荧光传感器的SD204型CTD对台湾海峡西南部海域627个站位的悬浮体特性进行了综合调查,并采集了底层沉积物。在室内分别利用英国Marlvern公司生产的Mastersizer 2000型激光粒度仪和德国ELEMENTOR公司生产的ELEMENTOR varioELIII型元素分析仪对表层沉积物进行了粒度分析和沉积物碳、氮含量测定,结果表明,台湾海峡西南部海域春季受粤东沿岸流、韩江冲淡水、九龙江冲淡水及台湾海峡混合水影响,其中粤东沿岸流在向北输运过程中影响强度逐渐减弱,韩江冲淡水影响范围较大,并且在西南季风的控制下向东北方向输运;长时间尺度的沉积物输运格局表明,近岸沉积物由岸向海输运,远海地区沉积物由海向岸输运,并且在汕尾南部海域、南澳岛东南部海域形成了沉积物的汇聚区,沉积物以陆源为主;表层沉积物的输运过程受控于区域内水团、悬浮体分布及运动格局;在春季上升流形成早期尽管叶绿素荧光值相对较低,但其对表层沉积物的输运过程起着非常重要的控制作用。  相似文献   

4.
台湾海峡1999年8月表层温盐的走航式观测   总被引:3,自引:0,他引:3  
利用1999年8月台湾海峡的调查资料中走航式温盐仪的资料,对该海区的表层温盐分布进行分析。分析结果表明:调查期间在该海区存在多处上升流和冲淡水。台湾海峡调查海区的上升流区大致可分为两类:(1)海峡西部沿岸上升流区:平潭上升流区、东山上升流区和南澳上升流区;92)台湾浅滩附近的上升流区。冲淡水主要有九龙江冲淡水、珠江冲淡水和闽江冲淡水,此外还有粤东沿岸水。  相似文献   

5.
为了研究海洋锋对声传播的影响,借鉴黑潮引起的台湾海峡南部海洋锋的历史水文观测资料,提出并建立了适合描述台湾海峡南部海洋锋的数学模型及其声速表达式。通过与实测资料对比,建立的海洋锋模型能准确反映客观实际情况,表现出较好的效果。同时,在借鉴了前人研究经验的基础上,采用Argo实测资料,建立了台湾海峡南部海洋锋的数学模型及其声速表达式,利用MMPE水下声场模型进行了海洋声场数值模拟试验,对目标海区典型的声场结构进行了声线路径模拟和传播损失的计算仿真,并将实验结果通过与前人进行的实际大洋声场实验的结果比较,证实了本文的模拟结果是准确可信的,提高了水声数值模拟试验的准确有效性。  相似文献   

6.
依据2006年夏季对东海区水文化学数据的现场调查, 对台湾暖流的水文化学特性进行了初步分析, 并对台湾暖流自身的水文化学特性对东海赤潮高发区的影响进行了初步探讨。结果表明, 夏季, 台湾暖流水具有台湾海峡水和黑潮次表层涌升水两个来源, 分别构成台湾暖流的表层水和深层水。通过亚硝酸盐含量的多少能够对表层水和深层水进行明显的区分。此外, 通过对台湾暖流水文特征的分析, 发现夏季台湾暖流在浙江沿海出现的上升流给赤潮生物提供了适宜的温度。并通过对台湾暖流的营养盐含量进行分析, 发现相对于硝酸盐含量, 台湾暖流含有较高的磷酸盐浓度, 能够缓解海区“过剩氮”导致的磷限制。  相似文献   

7.
黄海西南部陆架锋区锋断面环流数值模拟   总被引:3,自引:0,他引:3       下载免费PDF全文
浅水陆架锋是近岸混合区与外海层化区的分界面,对近海海雾形成、渔业生产及污染扩散有重要影响。赵保仁根据实测SST资料利用Simpson-Hunter参量提出黄海沿岸区域存在潮混合控制的浅水陆架锋,他还进一步指出,黄海沿陆架锋与冷水团边界区是黄海的主要上升流区,即锋面上升流区,夏季黄海西部沿岸存在沿冷水团锋面南下的强流。James用这一诊断模型讨论过锋区环流情况,Garret等用的是半诊断模型。他们均得出垂直于锋面的断面内在锋区附近存在着双环流结构。  相似文献   

8.
南黄海西部的陆架锋及冷水团锋区环流结构的初步研究   总被引:28,自引:8,他引:28  
赵保仁 《海洋与湖沼》1987,18(3):218-226
本文依据1984年7月的实测水文资料和卫星图片,指出了南黄海西部存在着因潮混合形成的浅水陆架锋,分析了陆架锋区的水文结构,指出在冷水团锋面区域海洋上层存在着一个因下层冷水上升而形成的低温、高盐、高氧带,沿陆架锋及冷水团边界区域,是黄海的主要上升流区。本文还指出,夏季黄海沿岸流主要是一支沿黄海冷水团锋面南下的强流(jet)。在冷水团衰退时期,随着冷水团的退缩,这一沿锋面的流动将向外海推移。  相似文献   

9.
台湾浅滩西侧水道夏季的水文特征与上升流   总被引:1,自引:3,他引:1  
本文根据1984年台湾海峡西部海域综合调查的结果及历史资料,分析了台湾浅滩西侧水道夏季的水文特征,以及这些特征与该海区夏季上升流的关系。并讨论了该海区夏季上升流海水的理化特征、上升流的时空变化及来源等。  相似文献   

10.
东海北部叶绿素a极大值的分布规律   总被引:10,自引:3,他引:7  
陆赛英 《海洋学报》1998,20(3):64-75
本文利用《中日黑潮合作调查研究(1986-1992)》的资料着重研究东海北部叶绿素a极大值在水平方向上的分布和季节变化规律等.研究表明,东海北部水动力环境,诸如锋面涡、海洋锋和上升流等等是促成叶绿素a极大值分布变化的重要环境因素.文中特别指出叶绿素a密集区离锋面远近的位置与锋面流速的跃变程度呈现一元线性负相关,可以通过此相关式来估计叶绿素a密集区的位置.  相似文献   

11.
东海温度锋的分布特征及其季节变异   总被引:8,自引:4,他引:8  
汤毓祥 《海洋与湖沼》1996,27(4):436-444
根据1934-1988年东海水文观测资料,重点分析东海温度锋的分布特征及其季节变异,并结合近期中日黑潮合作调查研究成果,初步探讨温度锋季节变异和水团演变的关系,所得主要结论是:(1)东海不仅常年存在浙闽沿岸锋,东海北部陆架锋和黑潮锋,而且、春、夏两季,在东海南部还出现一条东海中部出架锋。(2)江海温度锋季节变化的特点是:冬季,锋的宽度和强度皆是表层最强,夏季,表层温度锋仅出现在浙江近岸小范围海域。  相似文献   

12.
依据自适应数值模型,模拟了东中国海冬、夏季三维斜压Lagrange环流。模拟发现:台湾暖流的上层水来自台湾海峡入流和台湾东北黑潮的表层水;50m以下的深底层水主要由台湾东北黑潮的次表层水入侵陆架生成。冬季对马暖流外海一侧主要由黑潮水构成,而其近陆一侧由台湾暖流和陆架混合水构成,西朝鲜沿岸流在济州海峡汇入对马暖流;夏季它还包含转向后的长江冲淡水。冬季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,这与传统观点相悖,而与中韩黄海水循环动力学合作调查结果一致。黄海暖流东西两侧分别为2支向南流动的滑岸流。夏季黄海环流构成基本封闭的逆时针环流。冬季渤海环流主要有一逆时针大环流,但辽东湾的环流是顺时针向的。渤海环流冬强夏弱,水流在渤海海峡北进南出。  相似文献   

13.
The hydrographic surveys in an area immediately northeast of Taiwan showed that the Kuroshio surface water intruded onto the shelf in the spring and there was a thick mixed layer and weak vertical stratification in the Kuroshio at the time. During the summer season, a strong thermocline was developed in the Kuroshio and the flow shifted offshore from Taiwan in front of the continental shelf break of the East China Sea. A numerical model is used to examine the effect of this seasonal thermocline on the flow pattern of the survey area. We find that the surface strength of the disturbance above the Su-Ao ridge is closely related to the occurrence of the on-shelf intrusion of Kuroshio. The presence of a seasonal thermocline in the Kuroshio can greatly diminish this disturbance in the surface level.  相似文献   

14.
Circulation of the East China Sea,a numerical study   总被引:4,自引:0,他引:4  
A three-dimensional, primitive-equation model is developed to study how the Kuroshio, the monsoon, the Yangtze River outflow and the buoyancy forcing from the South China Sea affect the circulation of the East China Sea. It is found that the Kuroshio water usually intrudes into the East China Sea from both sides of Taiwan Island. Winter winds enhance the Kuroshio intrusion from northeast of Taiwan, but weaken it from the Taiwan Strait. Summer winds act in the opposite way. The increased presence of the Kuroshio water in the East China Sea in winter can be largely attributed to the shoreward surface Ekman drift associated with the northerly wind. In summer, the-shaped plume emanating from the Taiwan Strait is, to a large extent, produced by the buoyancy forcing from the South China Sea.In summer, the bimodal distribution of the Yangtze River outflow is initially produced by the upwelling-favorable wind. Away from the Yangtze River, the far-field dispersal of the fresher water depends on the strength of the Kuroshio. A stronger Kuroshio enhances the seaward dispersal of the northern branch of the Yangtze outflow north of Taiwan, but reduces the southward penetration of the southern branch. In winter, downwelling-favorable winds confine the Yangtze River outflow to a narrow band forming nearshore coastal jet penetrating southward. The northern tip of Taiwan acts as a conduit, channeling the seaward dispersal of the fresher water. The model results interpret the observed circulation patterns.  相似文献   

15.
东海西部陆架海域水团的季节特征分析   总被引:3,自引:1,他引:2  
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.  相似文献   

16.
As a fundamental study to evaluate the contribution of the Kuroshio to primary production in the East China Sea (ECS), we investigated the seasonal pattern of the intrusion from the Kuroshio onto the continental shelf of the ECS and the behavior of the intruded Kuroshio water, using the RIAM Ocean Model (RIAMOM). The total intruded volume transport across the 200m isobath line was evaluated as 2.74 Sv in winter and 2.47 Sv in summer, while the intruded transport below 80m was estimated to be 1.32 Sv in winter and 1.64 Sv in summer. Passive tracer experiments revealed that the main intrusion from the Kuroshio to the shelf area of the ECS, shallower than 80m, takes place through the lower layer northeast of Taiwan in summer, with a volume transport of 0.19 Sv. Comparative studies show several components affecting the intrusion of the Kuroshio across the 200 m isobath line. The Kuroshio water intruded less onto the shelf compared with a case without consideration of tide-induced bottom friction, especially northeast of Taiwan. The variations of the transport from the Taiwan Strait and the east of Taiwan have considerable effects on the intrusion of the Kuroshio onto the shelf.  相似文献   

17.
本文根据“中日黑潮合作调查”在东海的调查资料,探讨了硝酸盐的分布特征,以及水文条件对其分布的影响,并比较了不同年份夏季硝酸盐的分布差异及其原因。分析表明,表层海水中硝酸盐分布明显受长江冲淡水影响,陆架区测值高于外海,冬季测值高于夏季; 50m ,100m 层上陆架、黑潮锋区存在着硝酸盐锋面,黑潮主干的摆动可能是影响锋面位置的主要因素  相似文献   

18.
A. S. Kazmin 《Oceanology》2016,56(4):465-469
High-resolution satellite sea surface temperature measurements (PATHFINDER dataset) indicate that the fronts at the boundary of the East China Sea (Taiwan front, Kuroshio frontal zone, and South Korean coastal front) appear as a unified dominating frontal structure when climatological averaging is applied. This structure is about 1200 km in length, spreads over the continental shelf from Taiwan to the Tsushima Islands, and separates productive seawaters from the oligotrophic oceanic waters. The Kuroshio frontal zone, incorporated into this structure, reveals interannual variability with periods consistent with El Niño–Southern Oscillation (4–5 years).  相似文献   

19.
TheclusteranalysisofthewatermassesinwesternTaiwanStraitfromhydrologicandchemicalfactors¥HuangZiqiangandJiWeidong(ReceivedAugu...  相似文献   

20.
We studied the effect of four types of fronts, the coastal front, the middle front, the shelf partition front and the shelf break front on the quantitative distribution and the composition of plankton communities in the Pribilof area of the eastern Bering Sea shelf in late spring and summer of 1993 and 1994. The coastal fronts near St. Paul and St. George Islands and the coastal domains encircled by the fronts featured specific taxonomic composition of planktonic algae, high abundance and production of phytoplankton, as well as large numbers of heterotrophic nanoplankton. The coastal fronts also were characterized by high values of total mesozooplankton biomass, high concentrations of Calanus marshallae, as well as relatively high abundances of Parasagitta setosa and Euphausiacea compared to surrounding shelf waters. We hypothesize that wind-induced erosion of a weak thermocline in the inner part of the coastal front as well as transfrontal water exchange in subthermocline layers result in nutrient enrichment of the euphotic layer in the coastal fronts and coastal domains in summer time. This leads to prolonged high primary production and high phytoplankton biomass. In this paper a new type of front—the shelf partition front located 45–55 km to the north-east off St. Paul Island—is described, which is assumed to be formed by the flux of oceanic domain waters onto the shelf. This front features a high abundance of phytoplankton and a high level of primary production compared to the adjacent middle shelf. Near the southwestern periphery of the front a mesozooplankton peak occurred, composed of C. marshallae, with biomass in the subthermocline layer, reaching values typical for the shelf break front and the highest for the area. High abundance of phyto- and zooplankton as well as heterotrophic nanoplankton and elevated primary production were most often observed in the area adjacent to the shelf break front at its oceanic side. The phyto- and mesozooplankton peaks here were formed by oceanic community species. The summer levels of phytoplankton numbers, biomass and primary production in the shelf break frontal area were similar to those reported for the outer and middle shelf during the spring bloom and the coastal domains and coastal fronts in summer. In the environment with a narrow shelf to the south of St. George Island, the mesozooplankton peak was observed at the inner side of the shelf break front as close as 20 km from the island shore and was comprised of a “mixed” community of shelf and oceanic species. The biomass in the peak reached the highest values for the Pribilof area at 2.5 g mean wet weight m−3 in the 0–100 m layer. Details of the taxonomic composition and the numbers and production of phytoplankton hint at the similarity of processes that affect the phytoplankton summer community in the coastal domains of the islands, at the coastal fronts, and at the oceanic side of the shelf break front. The middle front was the only one that had no effect on plankton composition or its quantitative characteristics in June and July. Location of a variety of frontal productive areas within 100 km of the Pribilof Islands creates favorable foraging habitat for higher trophic level organisms, including sea birds and marine mammals, populating the islands.  相似文献   

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