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1.
东海东北部春季若干重要水文结构的分析   总被引:7,自引:2,他引:7  
本文主要基于韩国海洋研究所在东海沿岸海洋过程试验中收集的CTD资料,分析了1995年春季出现在东海东北部的一些重要水文结构。结果表明,一种锋涡状结构出现在黑潮向东转折点附近。它不仅使邻近海域的水文结构变得更复杂,而且诱发黑潮水与陆架水间活跃的交换。在陆架坡折处观测到若干孤立的陆架水块,可能是锋涡的卷挟作用所致;该海域存在4个水团,即黑潮水、对马暖流水、陆架水和混合水。对马暖流水分为上下两层:上层水为变性黑潮水,盐度比黑潮水约低0.1,底层对马暖流水仅位于冲绳海槽区,并有着与黑潮中层水相同的温、盐特性;一种双锋结构出现在邻近黑潮的陆架边缘附近。在内陆架形成的陆架锋,由北向南伸展时,愈来愈偏向陆架边缘。而黑潮锋沿九州以西深槽的陆架边缘向北伸展。在黑潮转折点附近,两锋几乎合并为一条锋。狭窄的锋带由黑潮水及其变性水和陆架水的混合水所占据。  相似文献   

2.
Sedimentological and micropaleontological characteristics of core sediments from the outer shelf of the Korea Strait, which connects the northern East China Sea and the East Sea (Sea of Japan), were investigated to elucidate the paleoceanographic environment, especially the timing of the Kuroshio inflow, since the last glacial maximum. The core sediments, containing continuous records of the last 15,000 years, are characterized by a relatively high mud content (more than 50%, on average) and well-developed tide-influenced sedimentary structures. Their mineralogy suggests that the material originated from the paleo-Nakdong River system, which extended across the shelf of the Korea Strait during low sea-level periods. Planktonic foraminifers reveal a series of well-defined changes in paleoceanographic conditions during the late Pleistocene–Holocene. Down-core variations in the abundance of four foraminiferal assemblages, i.e., cold, coastal, tropical–subtropical, and Kuroshio water groups comprising characteristic planktonic species, suggest the occurrence of a distinct paleoenvironmental change in the surface water at 7,000 years b.p., i.e., from 15,000 to 7,000 years b.p., the area was influenced by coastal waters whereas since ca. 7,000 years b.p., it has been under the influence of open-sea water related to the Kuroshio Current flow, associated with both higher temperature and higher salinity. In particular, Pulleniatina obliquiloculata increased markedly in abundance at this time, documenting the inflow of the Kuroshio into the study area. These data indicate that the coastal water stage terminated at ca. 7,000 years b.p. when the warm Kuroshio and its major branch, the Tsushima Current, began to flow into the East Sea, as is the case today. The intrusion of the Tsushima Current through the Korea Strait after ca. 7,000 years b.p. resulted in abrupt changes in sedimentation rates and a dramatic increase in abundance of the Kuroshio indicator species, P. obliquiloculata.  相似文献   

3.
本文主要根据韩国海洋研究所通过东海沿岸海洋过程试验(即COPEX-ECS)收集的CTD资料,较详细地研究了东海东北部夏季的水文状况.文中首先分析了夏季出现在该海域最重要的几件海洋现象.其中主要包括长江冲淡水的东向扩展,黄海底层冷水南向插入,以及黑潮水的爬升和渗透。然后,使用t-S分析法,并参考有关研究成果,对东海东北部夏季水团进行了划分,并重点探讨了黑潮水和对马暖流水的结构特征。最后,本文讨论了朝鲜/对马海峡东、西水道夏季水文结构的差异问题。  相似文献   

4.
根据1994年8月28日至9月7日韩国“Onnuri”号海洋调查船获得的CTD资料及在调查期间投放的11个卫星跟踪漂流浮标资料,分析研究了东海东北部黑潮水的分离及其与陆架水的相互作用,进而探讨了夏季的对马暖流的形成过程。  相似文献   

5.
东海和南黄海夏季环流的斜压模式   总被引:17,自引:6,他引:17  
王辉 《海洋与湖沼》1996,27(1):73-78
基于拉格朗日余流及其输运过程的一种三维空间弱非线性理论,引进了黑潮边界力及长江径流,给出了东海和南黄海的夏季环流及上升流区的分布。计算结果表明:在黑潮西侧存在着台湾-对马暖流系统;进入朝鲜海峡的对马暖流来自台湾暖流、黑潮、东海混合水和西朝鲜沿岸流;黄海暖流主要来源于东海混合水,表面有部分来自对马暖流;闽浙沿岸存在上升流区且构成一带状区域;在长江口外、东海东北部和陆坡上也存在在上升流式;陆坡处上升流  相似文献   

6.
本文通过二维数值模拟对1986年6月~1988年12月东海对马暖流水的来源问题进行了初步探讨,结果得出东海对马暖流水的来源基本上分为三种类型:(1)东海对马暖流水主要为东海黑潮水继续北上部分构成;(2)东海对马暖流水由东海黑潮水、东海陆架水以及东海北部黄海大陆沿岸水几部分混合而成;(3)东海对马暖流水几乎全部由东海北部的黄海大陆沿岸水构成。模拟与实测结果基本一致.  相似文献   

7.
Sea surface temperature (SST) and sea surface salinity variations at Fukue Island (located southwest of the Tsushima Straits) were investigated. In spring, low-frequency SST fluctuations with periods of 10–20 days predominate. Synthetic analysis of in situ observation and satellite infrared image reveals that these SST fluctuations are caused by movement of mixed warm water masses which have a temperature intermediate between those of the Kuroshio and the East China Sea (ECS) shelf waters. Since these fluctuations do not correspond with those in the Tsushima Straits, it is indicated that these water masses can hardly pass the Tsushima Straits while retaining their original water properties. In July, SST fluctuations with a period of several days are also found at Fukue Island. Since these SST fluctuations show an opposite correspondence with its salinity fluctuations and a good correspondence with the SST fluctuations at Okinoshima in the Tsushima Straits, it is inferred that warm and low-salinity water originated from the ECS shelf water causes these fluctuations and intrudes into the Tsushima Straits.  相似文献   

8.
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   

9.
Circulation in the upper and the intermediate layer of the East Sea is investigated by using a fine resolution, ocean general circulation model. Proper separation of the East Korean Warm Current from the coast is achieved by adopting the isopycnal mixing, and using the observed heat flux (Hirose et al., 1996) and the realistic wind stress (Na et al., 1992). The simulated surface circulation exhibits a remarkable seasonal variation in the flow patterns of the Nearshore Branch, the East Korean Warm Current and the Cold Currents. East of the Oki Bank, the Nearshore Branch follows the isobath of shelf topography from late winter to spring, while in summer and autumn it meanders offshore. The Nearshore Branch is accompanied by cyclonic and anticyclonic eddies in a fully developed meandering phase. The meandering and the eddy formation of the Nearshore Branch control the interior circulation in the Tsushima Current area. A recirculation gyre is developed in the region of the East Korean Warm Current in spring and grown up to an Ulleung Basin scale in summer. A subsurface water is mixed with the fresh surface water by winter convection in the northeastern coastal region of Korea. The well-mixed low salinity water is transported to the south by the Cold Currents, forming the salinity minimum layer (Intermediate Water) beneath the East Korean Warm Current water. The recirculation gyre redistributes the core water of the salinity minimum layer in the Ulleung Basin. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

10.
本文综合分析四个断面16个标准层的因子点聚,表明在整个海区有九个水团,即:黑潮表层水、黑潮次表层水、黑潮中层水、黑潮深层水、大陆沿岸水、台湾暖流水、黄海水、对马暖流水和东海混合水,前6个水团是该海区的主要水团。本文还详细讨论了每个水团的分布特征。  相似文献   

11.
Hydrographic conditions in the Tsushima Strait revisited   总被引:1,自引:1,他引:0  
Long-term averaged temperature and salinity distributions in the Tsushima Strait are investigated on the basis of a concurrent dataset of the eastern and western channels during 1971–2000. Both temperature and salinity show a clear seasonal variation with weak and strong stratifications in December–April and June–October, respectively. The largest standard deviations occur in summer around the thermocline for temperature and in the surface layer for salinity. This indicates large interannual variability in the development of a thermocline and low salinity water advection from the East China Sea. The water masses in both channels are distinctly different from each other; the water in the western channel is generally colder and fresher than that in the eastern channel throughout the year. Baroclinic transport based on the density distributions shows a seasonal variation with a single peak in August for the eastern channel and double peaks in April and August for the western channel. However, this cannot explain the seasonal variation in the total volume transport estimated from the sea level differences across the channels. The spatial distribution of baroclinic transport shows a year-round negative transport towards the East China Sea behind the Iki Island in the eastern part of the eastern channel. This negative transport reflects the baroclinic structure between the offshore Tsushima Current Water and cold coastal water. The corresponding southwestward currents are found in both Acoustic Doppler Current Profiler (ADCP) and high frequency (HF) radars observations.  相似文献   

12.
应用对应分析法划分夏季东海水团的初步研究   总被引:9,自引:1,他引:9       下载免费PDF全文
本文所用资料主要是日本气象厅等单位于1966年7月10日一8月10日所收集的溫、盐度和溶解氧的观测資料,共75个测站。测站分布均匀且遍及24°—32°N的整个东海海域(图1c)。  相似文献   

13.
基于2014年5—6月对黑潮主流径及毗邻东海陆架海区的调查,研究了该区域水体中无机碳体系参数(p H、总碱度TAlk、溶解无机碳DIC及DIC/TAlk)的垂直与水平分布,在此基础上定量评估了黑潮输入对东海陆架海区无机碳收支的影响。结果表明,黑潮水体中DIC、TAlk与DIC/TAlk总体而言随水深增加而升高,p H降低,综合体现了浮游植物生产、海-气界面交换、有机物降解及Ca CO3溶解等过程的影响;上升流中心站位无机碳参数均受较深层水体上涌影响,与黑潮主流径其它站位略有不同。东海陆架海区外侧站位表层、30m层无机碳主要受台湾海峡暖流影响,高p H、低DIC/TAlk的黑潮表层水影响区域局限于东南部;而在底层,低p H、高DIC/TAlk的黑潮入侵流离开黑潮主流径向正北方延伸并抬升至钱塘江口附近;上升流对无机碳的影响持续至表层,其携带的黑潮中层水因此也可能进入陆架海区。水量模型估算黑潮水在5—10月间跨域陆架边缘向东海陆架区输入溶解无机碳总计58798.9×109mol,净输入达37382.9×109mol,而东海向外输出的无机碳绝大部分经由对马海峡进入日本海。  相似文献   

14.
The Current System in the Yellow and East China Seas   总被引:18,自引:1,他引:18  
During the 1990s, our knowledge and understanding of the current system in the Yellow and East China Seas have grown significantly due primarily to new technologies for measuring surface currents and making high-resolution three-dimensional numerical model calculations. One of the most important new findings in this decade is direct evidence of the northward current west of Kyushu provided by satellite-tracked surface drifters. In the East China Sea shelf region, these recent studies indicate that in winter the Tsushima Warm Current has a single source, the Kuroshio Branch Current in the west of Kyushu, which transports a mixture of Kuroshio Water and Changjiang River Diluted Water northward. In summer the surface Tsushima Warm Current has multiple sources, i.e., the Taiwan Warm Current, the Kuroshio Branch Current to the north of Taiwan, and the Kuroshio Branch Current west of Kyushu. The summer surface circulation pattern in the East China Sea shelf region changes year-to-year corresponding to interannual variations in Changjiang River discharge. Questions concerning the Yellow Sea Warm Current, the Chinese Coastal Current in the Yellow Sea, the current field southwest of Kyushu, and the deep circulation in the Okinawa Trough remain to be addressed in the next decade. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

15.
The possible origin and cause of the less saline shelf water detected in the Kuroshio subsurface layer around the shelf edge of the East China Sea are investigated using observational results obtained in May 1998–2001 in conjunction with a dataset archived by Japan Oceanographic Data Center and a numerical model. The observations show that subsurface intrusions of less saline water are always detected in May in layers above 24.5σθ isopycnal surface, and that salinity inversions (i.e., areas in which the less saline water lies beneath the saline water) are detected around the trough of the Kuroshio frontal eddy (or wave). Analyses of the archived dataset reveal that the isopycnal surface of 24.5σθ is the deepest layer of the Kuroshio pycnocline outcropping to the sea surface on the shallow shelf in early spring. Outcropping isopycnals above 24.5σθ encounter a less saline water plume originating from the Changjiang, especially in the western East China Sea. Thereafter, the less saline water moves along isopycnal layers and reaches the Kuroshio front around the shelf edge. Numerical models demonstrate that, when the frontal wave captures the less saline water, the shelf water takes the form of a salinity inversion in the trough because isohalines in the frontal wave have a phase lag between the upper and lower layers in consequence of the baroclinic instability.  相似文献   

16.
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.  相似文献   

17.
基于ROMS(Regional Ocean Modeling System)模式,对西北太平洋海域进行了水平分辨率高达4km的水动力环境数值模拟,该分辨率可以很好地分辨我国东海陆架环流以及中尺度涡旋等过程,此外模式考虑了8个分潮,模式结果很好地再现了黄、东海陆架环流等。基于模式结果,对"桑吉"号泄漏物质可能的扩散和迁移轨迹进行了数值模拟分析。在"桑吉"号沉船位置的表、底Ekman层内,释放拉格朗日粒子和示踪物来示踪"桑吉"号泄漏物质的可能影响范围。拉格朗日粒子和示踪物模拟结果表明:在未来3个月,"桑吉"号泄漏物质对我国黄海的影响较小,其主要随着对马暖流进入日本海和随着黑潮进入日本九州以南的太平洋海域。随着冬、春的季节转换,三个月后,北风会减弱,减弱风场的试验表明,风场减弱会减少泄漏物质向黄海的输送。5月份后黄海冷水团逐渐形成,由于斜压效应,在黄海深层水中会逐渐建立起气旋式环流,从而进一步阻碍了"桑吉"号泄漏物质向黄海的输送,该气旋式环流有利于"桑吉"号泄漏物质通过对马海峡向日本海的输送,而会抑制底层泄漏物质向我国黄海西侧的输送。  相似文献   

18.
InteractionoftheKuroshiowaterandshelfwaterintheTsushimaCurrentregioninsummerGuoBinghuo,1Heung-JaeLie2andJaeHakLee2(ReceivedSe...  相似文献   

19.
Water mass properties along cross-sections of the Kuroshio in the East China Sea (ECS) are investigated in detail. We used temperature, salinity and dissolved oxygen data from 2000 and 2002, together with historical temperature and salinity data from 1987 to 2004. Water properties were divided into two groups: high and low salinities or oxygen at temperatures warmer than 15 and 12 °C, respectively. We found the existence of outer shelf water W2, as defined by clear modes in frequency distributions of salinity and oxygen within various temperature segments. The outer shelf water was different from both Kuroshio Tropical Water (KTW) and coastal water. We mapped horizontal and vertical distributions of W2, along with W1 and KTW. The outer shelf water was distributed with density σ t = 22.5–25.5 over a relatively broad area, from the outer continental shelf to the continental slope, particularly in autumn. Vertical distribution of the water suggests that W2 spread from the outer shelf to just the shelf side of the Kuroshio Current velocity maximum. Seasonal variations are examined with historical data along PN section over 17 years, and suggest that the appearance of W2 is distinct in summer and autumn. By comparing temperature–salinity (T–S) diagrams from Taiwan Strait and east of Taiwan, the outer shelf water (W2) originates from South China Sea Tropical Water (SCSTW), as suggested by Chen, J Geophys Res 110:C05012 (2005). The present study of the ECS clearly shows that SCSTW is transported along the east coast of Taiwan or through the Taiwan Strait into the ECS. It then spreads over a relatively wide area from the outer shelf to just the shelf side of the Kuroshio axis, and there is some horizontal mixing between SCSTW and KTW around the shelf break.  相似文献   

20.
《Oceanologica Acta》1998,21(5):713-716
Exchanges between the East China Sea (ECS) and the Kuroshio have been recalculated by taking into consideration the intra-annual variation of salinity on the shelf. Flux through the Taiwan Strait, previously unavailable data in the Yellow Sea and in the central and northern ECS, denitrification and ground water fluxes are now also considered. The Kuroshio Intermediate Water remains the major source of nutrients on the East China Sea continental shelf, with slightly more upwelling in the dry season than in the wet season.  相似文献   

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