首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 62 毫秒
1.
1IntroductionAlotofworkonthestudyofthecircula-tionintheHuanghai(Yellow)Sea(HS)andEastChinaSea(ECS)hasbeenmadeandreviewedbyscientists,suchasSu(1998),Suetal.(1994),Guan(1985),YuanandSu(1983,2000),Yuanetal.(1997,1988,1994,2001),Tangetal.(2000)andsoon.Inthispapertheseworks willnotbereviewedagainduetolimitationofpages.Thejointinvestigationontheair-seainteractionprocessofcycloneoutbreakoverthesouthernHuanghaiSeaandEastChinaSeawascarriedoutinthecooperativestudybytheChinese(in-clusiveofTaiwa…  相似文献   

2.
基于日本“长风丸”调查船在2000年5个航次水文资料及同时期QuikSCAT风场资料,采用改进逆方法计算了东海黑潮的流速与流量等,获得了这5个航次期间的主要结果:(1)在东海海区风速1~2月比其他月份时大,风海流也最强.只在7月表层风海流为北向,加强了黑潮流速.(2)表层最低盐度值夏季时最小,1~2月时最大.这再次表明,夏季时长江冲淡水向东北方向扩散,冬季时基本上向南,其他季节在上述两者之间.(3)PN断面流速结构及其变化:黑潮流核在1~2,10和11月时有两个,在4和7月皆只有1个.黑潮主流核在1月位于计算点9,在4,7,10与11月都位于计算点8,即向陆架方向移动.(4)黑潮在TK断面出现多流核结构特性.11月主流核出现在TK断面中部,存在于水深大于1 200 m区域,其余月份主流核皆出现在TK断面北部,存在于深度400m以浅水层.(5)通过PN断面的净东北向流量在11月最大,为28.1×106m3/s,7月时其次,10月时最小,为24.6×106m3/s.通过PN断面的净东北向流量年平均值为26.4×106m3/s.(6)1~2,4,7与10月在PN断面以东都出现暖的、反气旋式涡,10月份时,反气旋式涡最强.只在11月时出现弱的、气旋式涡.黑潮以东反气旋涡加强时,黑潮流量似乎减小(例如10月);相反,当黑潮以东反气旋涡减弱(例如7月)或者代之出现气旋涡时(例如11月),黑潮流量似乎增大.10和11月在PN断面附近流态的比较,揭示了环流变化较大,这进一步表明,黑潮和其附近中尺度涡的相互作用是重要的.(7)通过TK断面的净东向流量,11月最大,7月其次,10与1~2月最小.通过TK断面净东向流量年平均值为21.9×106m3/s.(8)通过A断面的北向流量在1~2与4月较大,分别为3.5×106与3.1×106m3/s,7月最小.通过A断面的年平均北向流量约为2.7×106m3/s,这表明,在2000年1~2与4月通过对马暖流的流量最大,7月时最小.  相似文献   

3.
Based on the wind and hydrographic data obtained by R/V Xiangyanghong 14 duringJune of 1999, the currents in the Huanghai Sea and East China Sea are computed by the three dimen-sional non-linear diagnostic, semidiagnostic models and prognostic in the σ coordinate. The computed re-sults show that the density and velocity fields and so on have been adjusted when time is about 3 days,namely the solution of semidiagnostic calculation is obtained. In the northwest part of the computed re-gion, the Huanghai coastal current flows southeastward, and then it flows out the computed region southof Cheju Island. In the west side of the southern part of the computed region, there is other current,which is mainly inshore branch of Taiwan Warm Current, and it flows cyclonically and turns to thenortheast. In the region north of the above two currents, there is a cyclonic eddy southwest of Cheju Is-land, and it has characteristics of high density and low temperature. There is an offshore branch of Tai-wan Warm Current in the west side of the Kuroshio, and it makes a cyclonic meander, then flows north-eastward. The Kuroshio in the East China Sea is stronger, and flows northeastward. Its maximum hori-zontal velocity is 108.5 cm/s at the sea surface, which is located at the northern boundary, and it is106.1 cm/s at 30 m level, 102.2 cm/s at 75 m level and 85.1 cm/s at 200 m level, respectively, whichare all located at the southern boundary. Comparing the results of diagnostic calculation with those ofsemidiagnostic and prognostic calculations indicates that the horizontal velocity field agrees qualitatively,and there is a little difference between them in quantity. The comparison between the computed veloci-ties and the obeered velocities at the mooring station show that they agree each other.  相似文献   

4.
On the basis of hydrographic data obtained during two October cruises of 1995, a modified inverse method is used to compute the Kuroshio east of Taiwan and the currents east of the Ryukyu-gunto.The net northward volume transport(VT) of the Kuroshio through Section TK2-K2 southeast of Taiwan is about 57.8×106 m3/s.There are four current cores of the Kuroshio at Section TK2-K2.Its main core is near the south of Taiwan, and its maximum speed is about 257 cm/s at the surface.After the Kuroshio flows through Section TK2-K2, there are three branches of the Kuroshio.The main branch of the Kuroshio flows northward into Section TKa east of Su''ao.The second branch of the Kuroshio flows northward through Section TKa and then enters the East China Sea through the region between Yonakunijima and Iriomote-shima.The net northward VT of the Kuroshio through Section TK4 is about 21.6×106 m3/s.The eastern branch of the Kuroshio flows northeastward through the region between a stronger cyclonic eddy and a recirculating anticyclonic gyre, and then flows continuously northeastward to the region east of the Ryūkyū-guntō and becomes a part of the origin of the western boundary current east of the Ryūkyū-guntō.Another part of the origin of the western boundary current east of the Ryūkyū-guntō comes from a recirculating anticyclonic gyre.From the above, in the regions east of Taiwan end east of the Ryūkyū-guntō the pattern of circulation during October of 1995 differs from the pattern of circulation during early summer of 1985.There are several eddies of different scales in this computational region.For example, there is a meso-scale stronger cyclonic eddy whose center is located at about 23°N, 124°20''E.  相似文献   

5.
依据黄、东海环流的的动力学模型 ,运用“流速分解法”对黄、东海正压环流进行了数值模拟。计算结果表明冬季黄海正压环流主要受风应力影响 ,基本形态为黄海暖流由济州岛西南进入南黄海中部 ,其东西两侧分别为两支向南流动的沿岸流 ;夏季主要受到潮致体力的影响 ,为一逆时针涡旋。东海环流主要是边界力作用驱动的结果 ,东海黑潮、台湾暖流和对马暖流较稳定。冬季风应力对东海环流表层流场有消弱作用 ,在夏季则有一定增强作用。  相似文献   

6.
东中国海环流及其季节变化的数值模拟   总被引:1,自引:0,他引:1  
关于东中国海环流的研究,国内外学者已做了大量的工作。早期科学家们主要依赖于对温盐资料和少数测流资料的分析研究对渤、黄、东海的环流结构有了较系统和深入的认识。东中国海环流是由一个气旋式的“流涡”组成,东侧主要是北上的黑潮-对马暖流-黄海暖流及其延伸部分;西侧为南下的沿岸流系。黑潮对东中国海环流的影响是如此之大,以致于除了某些局部区域外,上述海域主要流系的冬、夏季分布形式比较相似而无本质上的差异(胡敦欣等,1993)。但本文所研究海域正处于世界上最显著的季风区,冬、夏季盛行风向基本相反,过渡季节(春、秋季)风向多变,风力减弱;海洋热盐结构季节变化明显(如冬季混合强,而夏季层化明显等),这些因素都使得东中国海环流存在着较明显的季节变化。 自20世纪80年代以来,东中国海环流的数值模拟工作逐步展开,并已成为研究环流结构及其形成机制的强有力工具。但由于数值模式本身以及计算方案的缺陷(如有些学者用固定的风场、温盐场对东中国海环流进行诊断模拟等)和观测资料的不足,数值模拟的结果难以得到验证,渤、黄、东海的环流研究中仍有大量的问题存在争议,以待澄清。例如,台湾暖流的来源、流径;对马暖流的来源;夏季黄海暖流的流径以及黄海冷水团环流等均有不同的论述。对黄、东海环流季节变化的数值模拟工作也较少,多用冬、夏典型月份的风场强迫积分至稳定态,给出冬、夏季环流,这种做法值得商榷。三维环流模式很难在1个月内达到稳定态,尤其是夏季层化明显、风力减弱的情况下,非常定风场的影响更应引起人们的重视。 本文采用比较符合实际的计算方案,用年循环风场和海面热通量场为外强迫,对渤、黄、东海的环流及其季节变化进行了模拟,并对一些争议问题进行了探讨。  相似文献   

7.
Using hydrographic data and moored current meter records and the ADCP observed current data during May–June 1996, a modified inverse method is applied to calculate the Kuroshio east of Taiwan and in the East China Sea and the currents east of Ryukyu Islands. There are three branches of the Kuroshio east of Taiwan. The Kuroshio in the East China Sea comes from the main (first) and second branches of the Kuroshio east of Taiwan. The easternmost (third) branch of the Kuroshio flows northeastward to the region east of Ryukyu Islands. The net northward volume transports of the Kuroshio through Section K2 southeast of Taiwan and Section PN in the East China Sea are 44.4×106 and 27.2×106 m3s−1, respectively. The western boundary current east of Ryukyu Islands comes from the easternmost branch of the Kuroshio east of Taiwan and an anticyclonic recirculating gyre more east, making volume transports of 10 to 15×106 m3s−1. At about 21°N, 127°E southeast of Taiwan, there is a cold eddy which causes branching of the Kuroshio there.  相似文献   

8.
Variability of the Kuroshio in the East China Sea in 1992   总被引:3,自引:3,他引:0  
INTRODUCTIONMostofpreviousstudiesshowthatthedynamicmethodswereoftenusedtocomputethevelocityandVToftheKuroshiointheEastChinaSea(Guan,1988;Nishizawaetal.,1982;SunandKaneko,1993).Duringrecentyearsdifferentkindsofinversemethodshavebeentriedby*ThisprojectwassupportedbytheNationalNaturalScienceFoundationofChinaundercontractNo.49776287.1.Secondinstituteofoceanography,StateOceanicAdministration,Hangzhou310012,ChinaYuanetul(1988,1991,1992a,1992b,1993,1994,1995).Theircalculatedresultsshowt…  相似文献   

9.
基于日本气象厅“长风丸”调查船在2002年4~5月航次期间的CTD资料,结合卫星风场资料,采用改进逆方法计算了琉球群岛两侧海域各断面的流速和流量分布,并分析卫星跟踪浮标资料和同期的卫星高度计资料,得出下面一些主要结论:(1)黑潮流速在PN断面上只有一个流核.通过断面PN的净东北向流量约为34.7×106m3/s,此流量包括台湾暖流、东海黑潮和黑潮以东的反气旋涡的流量.(2)黑潮流速在断面TK上有两个流核,通过断面TK净东向的流量为25.6×106m3/s,黑潮通过海峡后流向断面ASUKA.(3)冲绳岛东南海区琉球海流的流量约为8.8×106m3/s,并流向断面AM.(4)奄美大岛以东的北向海流的流量为12.7×106m3/s,并流向断面ASUKA.在断面ASUKA东南部出现一个中尺度反气旋涡,直径约240 km,其流量约为28.5×106m3/s.(5)四国以南黑潮第一层水体基本来源于通过吐噶喇海峡的黑潮,第二、三层水体来自吐噶喇海峡和奄美大岛以东海域的流量大致相当,而第四层的流量则主要来自于奄美大岛以东海域.(6)浮标资料显示,奄美大岛以东的海流部分来自于断面AM以东海区,并通过断面ASUKA.  相似文献   

10.
The main processes of interaction between the coastal water, shelf water and Kuroshiowater in the Huanghai Sea (HS) and East China Sea (ECS) are analyzed based on the observation and study results in recent years. These processes include the intrusion of the Kuroshio water into the shelf area of the ECS, the entrainment of the shelf water into the Kuroshio, the seasonal process in the southern shelf area of the ECS controlled alternatively by the Taiwan Strait water and the Kuroshio water intruding into the shelf area, the interaction between the Kuroshio branch water, shelf mixed water and modified coastal water in the northeastern ECS, the water-exchange between the HS and ECS and the spread of the Changjiang diluted water.  相似文献   

11.
1992年东海黑潮的变异   总被引:10,自引:2,他引:8  
基于1992年4个航次的水文调查资料,运用改进逆方法计算了东海黑潮的流速、流量和热通量.计算结果表明:(1)PN断面黑潮在春季和秋季都有两个流核,冬季和夏季则只有一个流核.主核心皆位于坡折处.Vmax值春季最大,冬季和夏季次之,而秋季最小.黑潮以东及以下都存在逆流.(2)TK断面黑潮在冬季为两核,春、夏季为3核.海峡南端及海峡深处存在西向逆流.(3)通过A断面的对马暖流Vmax值在秋季最大,冬季最小.黄海暖流位于其西侧,相对较弱.(4)通过PN断面净北向流量夏季最大,秋季最小,而冬、春季介于上述二者之间,1992年四季平均值为28.0×106m3/s;TK断面的净东向流量也是在夏季最大;A断面净北向流量则在秋季最大.(5)PN断面4个航次的平均热通量为2.03×1015W.TK断面3个航次的平均热通量为2.00×1015W.(6)在计算海区,冬、春和秋季都是由海洋向大气放热;夏季则从大气吸热.冬季海面上热交换率最大,而夏季热交换率最小.关键词##4东海;;黑潮;;季节变化  相似文献   

12.
On the Huanghai (Yellow) Sea circulation: a review by current measurements   总被引:6,自引:1,他引:5  
INTRODUCTIONTheHuanghaiSea(hereafterHS)isashallow,semi-enclosedbasinsurroundedbytheChina'sMainlandtoitswestandmorth,andbytheKoreaPeninsulatOtheeast.TheHSreceivesabundantdischargeoffreshwaterandland-basedmaterialsthroughriversfromChinaandKorea,which ThisstudywassupportedbyagrantfromtheKoreaMinistryofaudienceandTechnoing.maybeaccumulatedpartlyinsidethebasinforacertainpenedormoveoutofthebasinintothenorthwesternEastChinaSea.TheHScirculationisknowntobemostlydependentuPOnsurfacewindfie…  相似文献   

13.
黄海、东海表、上层实测流分析   总被引:12,自引:3,他引:12  
根据迄今为止所获得的142套锚碇浮标和58套卫星跟踪漂流浮标的大范围测流资料,综合分析了黄海、东海表、上层环流。研究结果更加清晰、形象、直观地展示了黑潮及其向对马暖流的分支,台湾暖流的分叉,和黄海暖流、长江冲淡水及涡旋发达海区的若干主要特征。  相似文献   

14.
On the basis of the current measurements at 200,500 and 800 m from moored current meters with the time series data from March 17 to April 15 at the mooring station (20°49′57″N, 120°48′ 12″E) and the hydrographic data obtained in the Luzon Strait during the spring of 2002 cruise, the circulation in the investigated  相似文献   

15.
综述东海和琉球群岛以东海域若干气旋型和反气旋型涡旋的研究.对东海陆架、200m以浅海域,主要讨论了东海西南部反气旋涡、济州岛西南气旋式涡和长江口东北气旋式冷涡.东海两侧和陆坡附近出现了各种不同尺度的涡旋,其动力原因之一是与东海黑潮弯曲现象有很大关系,其次也与地形、琉球群岛存在等有关.东海黑潮有两种类型弯曲:黑潮锋弯曲和黑潮路径弯曲.黑潮第一种弯曲出现了锋面涡旋,评述了锋面涡旋的存在时间尺度与空间尺度和结构等;也指出了黑潮第二种弯曲,即路径弯曲时在其两侧出现了中尺度气旋式和反气旋涡,讨论了它们的变化的特性.特别讨论了冲绳北段黑潮弯曲路径和中尺度涡的相互作用,着重指出,当气旋式涡在冲绳海槽北段成长,并充分地发展,其周期约在1~3个月时,它的空间尺度成长到约为200km(此尺度相当于冲绳海槽的纬向尺度)时,黑潮路径从北段转移到南段.也分析了东海黑潮流量和其附近中尺度涡的相互作用.最后指出在琉球群岛以东、以南海域,经常出现各种不同的中尺度反气旋式和气旋式涡,讨论了它们在时间与空间尺度上变化的特征.  相似文献   

16.
Synoptic features in/around thermal fronts and cross-frontal heat fluxes in the southern Huanghai./Yellow Sea and East China Sea (HES) were examined using the data collected from four airborne expendable bathythermograph surveys with horizontal approxmately 35 km and vertical 1 m(from the surface to 400 m deep) spacings. Since the fronts are strongly affected by HES current system, the synoptic thermal features in/around them represent the interaction of currents with surrounding water masses. These features can not be obtained from climatological data. The identified thermal features are listed as follows : ( 1 ) multiple boundaries of cold water, asymmetric thermocline intrusion, locally-split front by homogeneous water of approxmately 18 ℃, and mergence of the front by the Taiwan Warm Current in/around summertime southern Cheju - Changjiang/Yangtze front and Tsushima front; (2) springtime frontal eddy-like feature around Tsushima front; (3) year-round cyclonic meandering and summertime temperature-inversion at the bottom of the surface mixed layer in Cheju - Tsushima front; and (4) multistructure of Kuroshio front. In the Kuroshio front the mean variance of vertical temperature gradient is an order of degree smaller than that in other HES fronts. The southern Cheju- Changjiang front and Cheju -Tsushima front are connected with each other in the summer with comparable cross-frontal temperature gradient. However, cross-frontal heat flux and lateral eddy diffusivity are stronger in the southern Cheju - Changjiang front. The cross-frontal heat exchange is the largest in the mixing zone between the modified Huanghai Sea bottom cold water and the Tsushima Warm Current, which is attributable to enhanced thermocline intrusions.  相似文献   

17.
为了探究东海黑潮周边涡旋分布、形成机理及运动规律,基于法国国家空间研究中心(CNES)卫星海洋学存档数据中心(AVISO)的中尺度涡旋数据集展开了研究。首先,统计了近27年东海黑潮周边的涡旋分布,发现在黑潮弯曲海域产生了650个涡旋,在黑潮中段海域产生了271个涡旋,其中直径100~150 km之间的涡旋数量最多,涡旋振幅主要集中在2~6 cm。其次,分析了东海黑潮的运动路径和涡运动过程,结果表明,黑潮气旋式弯曲海域内侧易产生气旋涡,且移动路径较长,如台湾东北海域黑潮流轴气旋式弯曲处产生的涡旋,其平均位移达到了87.6 km;当反气旋式弯曲海域内侧产生反气旋涡时,涡旋往往做徘徊运动。黑潮中段海域的涡旋呈现出气旋涡在黑潮主轴西侧、反气旋涡在黑潮主轴东侧的极性对称分布特征,两类涡都沿黑潮主轴向东北方向移动。最后,结合再分析的流场、海面高度数据,讨论了涡旋运动规律和生成机制。黑潮弯曲处涡旋的生成与黑潮流体边界层分离有关,奄美大岛南部到冲绳岛西侧的黑潮逆流对黑潮中段海域涡的极性对称分布起到了关键作用,涡旋在运动过程中通常经历生长、成熟和衰变三个阶段。  相似文献   

18.
The seasonal circulation in the southeastern Huanghai Sea has been studied with hydrographic data,which were observed in February and June 1994 and bimonthly during 1970-1990,and numerical model results.Horiwntal distributions of temperature and salinity in 1994 are quite different due to strong tidal mixing so that we need a analysis to see the real distributions of water masses.The mixing ratio analysis with the data of 1970-1990 shows the connection of the waters in the west coasts of Kotea Peninsula with warm and saline waters from the south in summer,which means northward inflows along the west coasts of Korea Peninsula in summer.With this flow,the seasonal circulations,which are deduced from the seasonal change of water mass distributions in the lower layer,are warm inflows in winter and mld outflows in summer in the central Huanghai Sea,and cold outflows in winter and warm inflows in summer along the west coasts of Korea Peninsula.The seasonally changed inflows might be the Huanghai Sea Warm Current.The monsoon winds can drive such circulations.However,summer monsoon winds are weak and irregular.As one of other possible dynamics,the variation of Kuroshio transport is numerically studied with allowing sea level fluctuations.Although it should be studied more,it possibly drives the summer circulations.The real circulations seem to be driven by both of them.  相似文献   

19.
Three warm currents, the Kuroshio, its shelf intrusion branch in the northeast of Taiwan and the Taiwan Warm Current (hereafter TWC), dominate the circulation pattern in the East China Sea (hereafter ECS). Their origination, routes and variation in winter and summer are studied. Their relationship with four major high and low temperature centers is analyzed. Differing from the previous opinion, we suggest that the four major centers are generated to a great extent by the interaction of the currents in the ECS. In summer, a cold water belt in the northeast of Taiwan is preserved from winter between the Kuroshio and the TWC. The shelf intrusion branch of the Kuroshio separates the water belt, and two low temperature centers generate in the northeast of Taiwan. In the southern ECS, the TWC transports more heat flux northward to form a warm pool. But it is separated in the lower layer by the cold water driven by the intrusion branch of the Kuroshio. So the TWC and the intrusion branch of the Kuroshio play a dominating role to generate the high temperature center. The interaction among the eastward TWC, the northward Tsushima Warm Current (hereafter TSWC) and the southward Su Bei Coastal Flow (hereafter SBCF) generates the low temperature center in the northern ECS. In winter, the strengthening of the shelf intrusion branch of the Kuroshio obscures the two low temperature centers in the northeast of Taiwan. For the weakening of the TWC, the high temperature center in the southern ECS vanishes, and the low temperature center in the northern ECS shifts to south.  相似文献   

20.
通过一个全球的二维诊断模型,采用Levitus温盐资料和COADS风应力资料,并结合动力计算来研究南海上层环流的季节变化。计算结果与其它模式结果和观测结果非常相似。南海北部(南部)全年存在一气旋式(反气旋式)环流。在冬季气旋式环流几乎占据了整个南海,夏季则以反气旋式环流为主。泰国湾的环流在冬季(夏季)是气旋式的(反气旋的)。南海的西边界流有明显的季节变化,其在冬季从卡里马塔海峡流出南海,夏季部分西边界流从台湾海峡流出南海。越南离岸流在春季就开始出现,其位置比夏季的越南离岸流的位置偏北。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号