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1.
北黄海定点连续观测站海流资料分析   总被引:2,自引:0,他引:2  
本文利用2009年6月至11月期间的ADCP海流资料,研究了獐子岛附近一个固定观测点处的时间平均流及潮流特征。结果表明,该海区的平均流大致沿等深线方向,从黄海流向渤海,整个观测期间纬向平均流大于经向平均流,经向1m宽度范围内的纬向净水体输运量为0.67m3/s,而纬向1m宽度内的经向净水体输运量为0.16m3/s;垂向上可以15m和47m为节点分为三层,15m大致为温跃层深度,而47m以下为底摩擦影响显著的范围。夏季的温盐层化结构对于余流的垂直分布存在显著影响。潮流调和分析表明,该海区的潮汐类型为正规半日潮,M_2和K_1分潮在整个深度范围内的平均振幅分别为27.9cm/s和9.2cm/s,半日潮流由表及底均为旋转流,而全日潮流更趋向于往复流。在垂向上,各个分潮的潮流椭圆均随深度发生小幅度的旋转,半日潮流椭圆随深度逆时针旋转,倾角变化小于30°,全日潮流椭圆随深度顺时针旋转,倾角变化小于40°。潮流在近底层受到底摩擦的影响十分显著,其中全日潮流受到底摩擦的影响较半日潮流大。本次观测是进一步研究北黄海区域潮流、近惯性流动与水体交换输运的直接参考,其结果加深了对该区域流场特性的认识和理解。  相似文献   

2.
2012年南海西北陆架冬季水文特征的观测分析   总被引:1,自引:0,他引:1  
本文基于2012年12月南海西北部陆架海区的温盐和流速实测资料,分析了粤西和琼东陆架海区冬季三维温、盐结构和流场特征,给出沿陆架和跨陆架方向的水体和热盐通量。结果表明:(1)在50m以浅,粤西和琼东海区温度均由近岸向外海递增,深层则相反;冬季近岸海区混合层较深,外海密度跃层位于60—120m深度且层结较强,浮力频率大于10–2/s;(2)海流大致沿等深线向西南流动,30m以深流速大小在0.03—0.40m/s之间,且随着深度增加而略有减小;琼东海区100m等深线附近在60m以浅水层观测到水体辐聚并有明显温度锋面存在;(3)沿陆架方向的水体和热盐输送均大于跨陆架方向,其中粤西单位面积沿/跨陆架水体通量平均值为0.13×10–6/0.03×10–6Sv/m2,低于琼东海区的0.91×10–6/0.56×10–6Sv/m2。  相似文献   

3.
主要根据台湾海峡的实测海流资料,以夏、冬为代表季节,分析了台湾海峡2—3个纬向断面的海流结构,计算出各断面的海水通量。结果表明:夏季,台湾海峡中、北部海域各层的海流一般偏N向流动,N向的海水净通量为3.32×106m3·s-1;冬季,高温高盐的黑潮水和南海水由南向北经南部断面进入台湾海峡,其海水通量分别为1.69×106m3·s-1和0.59×106m3·s-1;而东海水由北向南通过北部断面进入台湾海峡,其海水通量为1.02×106m3·s-1,其中,有0.40×106m3·s-1的海水沿着福建和广东近岸流进南海,其余0.62×106m3·s-1的海水在台湾海峡北部混合后随同黑潮水和南海水流入东海。总之,流经台湾海峡的N向海水净通量为1.74×106m3·s-1。  相似文献   

4.
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   

5.
琼州海峡是海南岛与雷州半岛之间重要交通通道,也是南海与北部湾两个海区水交换通道。最大涨落潮流速位于海峡北部和中部,且涨潮流速小于落潮流速;余流方向从东向西,最大余流位于北部;大潮期间向西输运从而进入北部湾的水体是0.0484Sv,小潮期间向西输运的水体则减少到0.0195Sv。向南的水量输运,大潮期间为0.1001Sv,小潮期间则降到0.0598Sv。向南输运的水量是由于海峡中间存在一个气旋环流引起的。  相似文献   

6.
本文根据台湾海峡南部海区夏季的海流调查资料,参考温、盐、密度等的历史资料和有关方面的研究成果,论述了表层、中层和下层的海流结构。结果表明,南海暖流继续沿着海区中部向东北延伸,但在粤东、闽南近岸的表层这支海流还受到沿岸低盐海水的影响;而黑潮南海分支北段的边缘部分可以影响到本海区的南部海域,这一部分还可能有一支流分出并沿着台湾岛西岸北上。  相似文献   

7.
东海黑潮与陆架海之间的水交换研究   总被引:1,自引:0,他引:1       下载免费PDF全文
利用三维海洋环流数值模型(Regional Ocean Model System,ROMS)对东中国海海域黑潮流系系统(东中国海黑潮流系)的季节变化和年际变化进行了模拟和研究,给出了东海黑潮流系穿越东海大陆架200 m等深线的体积通量及其变化规律。研究发现,黑潮的西南段,其主轴位置在春、夏季更加偏东;中间段具有最稳定的流径;而东北段则表现出最大的季节性变化。此外,从月平均结果看,黑潮流系穿越东海大陆架200 m等深线的体积通量,时间上表现为,在夏季减到最小,为0.479 6 Sv(1 Sv≡10~6m~3·s~(-1)),冬季达到最大值,为1.69 Sv;空间上表现为在西南段和中间段较大,而东北段较小。这反映了黑潮水与东中国海大陆架水的水交换区位置,在冬季在向岸方向上离黑潮主轴较远,在夏季离主轴较近。通过对长时间模型结果的时间序列分析,揭示了相对与2000年前,2000年后的黑潮在台湾岛东部水体积通量的季节变化呈现出减弱的趋势。  相似文献   

8.
基于2019年6月在蓬莱近岸海域实地观测获取的样品和数据,研究了海流、温度、盐度和悬浮泥沙的时空分布特征,利用小波分析、单宽通量机制分解和Richardson数等方法,探讨了悬浮泥沙的输运机制和控制因素。研究区悬浮泥沙在平面上呈以登州浅滩为中心向周围海域逐渐降低的分布特征,垂向上呈由表层至底层逐渐升高的趋势。悬浮泥沙浓度变化与潮流变化具有较好的正相关关系,但在时间上滞后1~2 h。研究区单宽净输沙率为7.84~43.12 g/(s·m)。平流输运在研究区悬浮泥沙输运过程中占主导地位,垂向净环流输运次之。潮流是研究区悬浮泥沙输运的主要动力,悬浮泥沙净输运方向与余流方向一致,登州水道南部悬浮泥沙由西向东输运,水道中部悬浮泥沙由东向西输运,南长山岛两侧悬浮泥沙呈向水道输运的趋势。研究区海域部分水体层化现象明显,水体混合受到抑制,悬浮泥沙的分布和输运受到潮流、水体混合和地形地貌共同控制。  相似文献   

9.
杨金湘  王佳 《海洋学报》2018,40(4):30-40
本文建立了一个气候态驱动的台湾海峡物理-生态耦合模型(ROMS-NPZD)。与遥感观测数据的比较表明,模型能够较好地模拟出冬、夏季台湾海峡主要的温度和叶绿素分布特征。模型揭示了夏季台湾海峡营养盐输运的东、西通道,与南海次表层水的入侵通道一致;冬季,海峡中的营养盐来源于闽浙沿岸水和通过澎湖水道入侵的南海次表层水。模拟结果表明:夏季,通过海峡流入东海的氮主要为有机氮;冬季,闽浙沿岸流为海峡和南海北部陆架提供了丰富的营养盐,不仅如此,南海次表层水进入海峡的营养盐通量与夏季相当。  相似文献   

10.
根据中国近海高分辨率 ( 1 / 6°)环流模式的模拟结果 ,计算了南沙邻近海域与外海之间的海水体积、热量和盐量输运及其对印度尼西亚贯穿流的贡献。研究海域为 0°— 1 4°N的整个南海南部海域。计算得出 ,穿过研究海域流向印度尼西亚海域 ,最终流向印度洋的年平均体积、热量和盐量输运分别为 5 .2Sv( 1Sv =1× 1 0 6m3·s- 1 )、0 .5 7PW和 1 84Gg·s- 1 ,大约占印度尼西亚贯穿流相应输运量的 1 / 4。这一结果表明南海是全球大传送带这一全球海洋最主要热盐环流系统的重要通道之一。从南海流向印度尼西亚海域的通道以卡里马塔海峡为最主要 ,以下依次为巴拉巴克海峡、民都洛海峡和马六甲海峡。大的南向通量主要发生在冬、秋季 ,春末夏初总的通量向北。计算还得出输入本海区的热输运量比输出少 0 .0 64PW ,由这一结果推得 ,通过海 -气界面由大气进入海洋的年平均净热通量约为 30W·m- 2 。  相似文献   

11.
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   

12.
In order to quantitatively estimate the volume and property transports between the South China Sea and Indonesian Seas via the Karimata Strait, two trawl-resistant bottom mounts, with ADCPs embedded, were deployed in the strait to measure the velocity profile as part of the South China Sea-Indonesian Seas transport/exchange (SITE) program. A pair of surface and bottom acoustic modems was employed to transfer the measured velocity without recovering the mooring. The advantage and problems of the instruments in this field work are reported and discussed. The field observations confirm the existence of the South China Sea branch of Indonesian throughflow via the Karimata Strait with a stronger southward flow in boreal winter and weaker southward bottom flow in boreal summer, beneath the upper layer northward (reversal) flow. The estimate of the averaged volume, heat and freshwater transports from December 2007 to March 2008 (winter) is (-2.7 ± 1.1) × 10 6 m3/s, (-0.30 ± 0.11) PW, (-0.18 ± 0.07) × 106m3/s and from May to September 2008 (summer) is (1.2 ± 0.6) × 106m3/s, (0.14 ± 0.03) PW, (0.12 ± 0.04) × 106m3/s and for the entire record from December 2007 to October 2008 is (-0.5 ± 1.9) × 10 6 m3/s, (-0.05 ± 0.22) PW, (-0.01 ± 0.15) × 106m3/s (negative/positive represents southward/northward transport), respectively. The existence of southward bottom flow in boreal summer implies that the downward sea surface slope from north to south as found by Fang et al. (2010) for winter is a year-round phenomenon.  相似文献   

13.
东海与邻近海域水、热、盐通量的季节变化研究   总被引:1,自引:0,他引:1  
本文基于高分辨率的区域海洋数值模式对东海及邻近海域进行温、盐、流的数值模拟,模拟结果与实测结果拟合较好。结果表明:东海与邻近海域的水交换过程具有显著的季节变化特征。从流量的角度看,台湾海峡、台湾-西表岛之间水道和西表岛-冲绳岛之间水道是外海水流入东海的3个主要水道,而冲绳岛-奄美大岛、吐噶喇海峡、大隅海峡、济州岛东部和黄东海断面是海水流出东海的水道;其年平均体积输运值分别为1.06×106 m3/s、20.49×106 m3/s、3.20×106 m3/s、-0.92×106 m3/s、-20.59×106 m3/s、-0.30×106 m3/s、-2.37×106 m3/s和-0.37×106 m3/s(向内为正)。对比发现,东海与邻近海域之间各水道的体积、热量和盐量输运均具有相似的季节变化趋势,其最大值往往出现在夏季(7月或8月),最小值往往出现在冬季(1月或2月)。从7月到11月整个东海是流量净流出的过程,而从12月到翌年6月是流量净流入的过程,全年流量基本上保持平衡状态。东海终年存在向黄海的净输入,其体积、热量和盐量的年平均输运值分别为0.37×106 m3/s,0.027×1015 W和12.7×106 kg/s。  相似文献   

14.
Review on current and seawater volume transport through the Taiwan Strait   总被引:12,自引:0,他引:12  
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.  相似文献   

15.
卡里马塔海峡水体交换的季节变化   总被引:2,自引:0,他引:2  
Four trawl-resistant bottom mounts, with acoustic Doppler current profilers(ADCPs) embedded, were deployed in the Karimata Strait from November 2008 to June 2015 as part of the South China Sea-Indonesian Seas Transport/Exchange and Impact on Seasonal Fish Migration(SITE) Program, to estimate the volume and property transport between the South China Sea and Indonesian seas via the strait. The observed current data reveal that the volume transport through the Karimata Strait exhibits significant seasonal variation. The winteraveraged(from December to February) transport is –1.99 Sv(1 Sv=1×10~6 m~3/s), while in the boreal summer(from June to August), the average transport is 0.69 Sv. Moreover, the average transport from January 2009 to December2014 is –0.74 Sv(the positive/negative value indicates northward/southward transport). May and September are the transition period. In May, the currents in the Karimata Strait turn northward, consistent with the local monsoon. In September, the southeasterly trade wind is still present over the strait, driving surface water northward, whereas the bottom flow reverses direction, possibly because of the pressure gradient across the strait from north to south.  相似文献   

16.
This study discusses branching of the Kuroshio Current including North Pacific Intermediate Water (NPIW) into the South China Sea (SCS). The spreading path of the subtropical salinity minimum of NPIW is southwestward pointing to the Luzon Strait between Taiwan and Luzon islands. Using a large collection of updated hydrography, results show that the SCS is a cul-de-sac for the subtropical NPIW because even the NPIW’s upper boundary neutral density surface σ N = 26.5 is completely blocked by the Palawan sill and partly blocked by the southern Mindoro Strait. In autumn, NPIW is driven out of the Luzon Strait by the preceding anticyclonic summer monsoon due to an intraseasonal variation and seasonal phase lag response to the weaker summer monsoon. Stronger inflow under winter monsoon than outflow under summer monsoon results in a net annual transport of NPIW of about 1.1 ± 0.2 Sv (1 Sv = 106 m3s−1) into the SCS. This net transport accounts for the anomaly in NPIW transport across the World Ocean Circulation Experiment section P8 (130° E). An earlier study estimated a large westward NPIW transport of about 3.9 ± 0.2 Sv, resulting in a difference of 1.2 ± 0.2 Sv from the basin-wide mean of 2.7 ± 0.2 Sv. Observations are generally in agreement with numerical results although the intraseasonal signal seems to cause a slight bias and remains to be simulated by future model experiments.  相似文献   

17.
The Luzon Strait transport variations during 1997~2000   总被引:1,自引:0,他引:1  
1IntroductionTheSouthChinaSea(SCS)isthelargestmarginalseainSoutheastAsia.TheSCSiscon-nectedtotheopenoceanthroughseveralstraitsbetweenthesurroundinglandmassesandis-lands.TheLuzonStrait(seeFig.1)islocatedinthenortheastoftheSCSbetweenTaiwanIslandandthePhilippineIslands,whichisabout380kmwideanditslargestdepthismorethan2500m.Sincetheotherstraitsareveryshallow,theLuzonStraitistheonlymajorchannelallowingeffectivewaterexchangewiththewesternNorthPacific. Wyrtki(1961)firstlyassocia…  相似文献   

18.
The vertical structure of the Soya Warm Current (SWC) was observed by a bottom-mounted acoustic Doppler current profiler (ADCP) in the region of the SWC axis near the Soya Strait during a 1-year period from May 2004. The ADCP data revealed a marked seasonal variability in the vertical structure, with positive (negative) vertical shear in summer and fall (winter and spring). The volume transport of the SWC is estimated on the basis of both the vertical structure observed by the ADCP and horizontal structure observed by the ocean radars near the strait. The transport estimates have a minimum in winter and a maximum in fall, with the yearly-averaged values in the range of 0.94–1.04 Sv (1 Sv = 106 m3 s−1). These lie within a reasonable range in comparison to those through other straits in the Japan Sea.  相似文献   

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