The South China Sea,a <Emphasis Type="Italic">cul-de-sac</Emphasis> of North Pacific Intermediate Water   总被引：1，自引：0，他引：1  

Yuzhu?YouEmail author  Ching-Sheng?Chern  Yih?Yang  Cho-Teng?Liu  Kon-Kee?Liu  Su-Cheng?Pai 《Journal of Oceanography》2005,61(3):509-527

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   

闽粤交界的大埕湾岸滩稳定分析及岸滩防护对策   总被引：1，自引：0，他引：1  

蔡锋  苏贤泽  高智勇  陈坚 《台湾海峡》2003,22(4):518-525

本文在实地调查的基础上，通过对大埕湾沿岸输沙率变化和岸线形态的分析，综合探讨了该海湾的泥沙来源，沿岸泥沙迁移特征，岸滩冲淤动态以及海岸的演变趋势．结果表明：该湾沿岸带形成了一股朝W向迁移的波生泥沙流，泥沙主要来自诏安湾和宫口湾；该湾海岸除东部沙坝泻湖岸段略有淤伸外，其余岸段均处于侵蚀状态：随着泥沙来源的减少，海岸内凹蚀退是今后岸线调整的自然过程．文中还对大埕湾岸滩的防侵蚀提出了相应的对策建议。  相似文献   

The physiological status and mortality associated with otter-trawl capture, transport, and captivity of an exploited elasmobranch, Squalus acanthias     

Mandelman  John W.; Farrington  Marianne A. 《ICES Journal of Marine Science》2007,64(1):122-130

  相似文献   

A method to measure suspended load transports in estuaries     

G. Krause  K. Ohm 《Estuarine, Coastal and Shelf Science》1984,19(6):611-618

It is shown that an optical beam-attenuance meter integrated into an Aanderaa current meter is a suitable device for measuring time series of fluxes of suspended material in turbid estuarine water. Some typical applications are presented.  相似文献   

Significance of Shallow Bottom Friction in the Dynamics of the Tsushima Current   总被引：1，自引：0，他引：1  

Young Ho Seung 《Journal of Oceanography》2003,59(1):113-118

A simple analytical model is considered for the dynamics of volume transport of the Tsushima Current. This model is basically baroclinic but allows bottom friction over the shallow regions connecting the Pacific Ocean to the Japan Sea basin, and is thus different from previous models which are either purely barotropic with bottom friction predominating over the whole domain, or purely baroclinic with bottom friction completely ignored. Compared to the previous barotropic model, this model is not only more realistic but also gives much simpler results. It gives the observed downstream sea level slope, which is not seen in the previous baroclinic model. As a result, the estimated transport of the Tsushima Current is closer to the observational data than those of previous models. This model indicates that the localized bottom friction acting over the shallow regions not only controls the transport of the Tsushima Current but also moves the stagnation point of the western boundary current northward. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

二阶Boussinesq方程的孤立波解     

林建国  邱大洪 《海洋与湖沼》2001,32(3):334-339

基于同量阶迭代法，在保留同阶面的前提下，对林建国等（1998a)得到的二阶Boussinesq类方程进行了求解，得到了与其量阶相对应的取立波解，并春与Euler方程的二阶孤立波解进行了比较，结果显示，本文解比传统Boussinesq方程的孤立波解有明显的改善，扩大了孤立的适用范围。  相似文献   

Numerical flow analysis of single-stage ducted marine propulsor   总被引：1，自引：0，他引：1  

Warn-Gyu Park  Young-Rae Jung  Chan-Ki Kim 《Ocean Engineering》2005,32(10):1260-1277

The present work has solved 3D incompressible RANS equations on a rotating, non-orthogonal multi-blocked grid to efficiently analyze a ducted marine propulsor with rotor–stator interaction. To handle the interface boundary between a rotor and a stator, the sliding multi-block technique using the cubic spline interpolation and the bilinear interpolation was applied. To validate the present code, the flow of a single stage turbine flow was simulated. Time averaged pressure coefficients were compared with experiments and good agreements were obtained. After the code validation, the flowfield around a single-stage ducted marine propulsor having a single stage of rotor and stator was successfully simulated and the hydrodynamic performance coefficients were computed.  相似文献   

Sedimentary processes on an intertidal mudflat in the upper macrotidal Seine estuary, France     

J. Deloffre  R. Lafite  P. Lesueur  S. Lesourd  R. Verney  L. Guzennec 《Estuarine, Coastal and Shelf Science》2005,64(4):1073

In order to understand the hydrodynamic parameters that control the fluvial sediment dynamics on an intertidal mudflat located in a sheltered zone in the upper part (fluvial part) of the macrotidal Seine estuary (France), a two-year field study of high-frequency field measurements was carried out. The bed-level evolution of the mudflat surface was measured from the semi-diurnal period to annual time scales using a high-resolution altimeter. The data showed that the sedimentary patterns on the mudflat were mainly controlled by river flows and tides. During high river flows in winter, sedimentation dominated; suspended particulate matter concentrations were higher, submersion was constant and at semi-diurnal scale, sedimentation duration was more important than erosion due to an asymmetrical tide. By contrast during low river flows in summer, erosion dominated mainly as a result of immersion/emersion of tidal flats during semi-diurnal cycle. From this annual sedimentation–erosion cycle we identify a temporary storage of 10–30% of the fine-grained (<63 μm) river-borne particles on mudflats in the upper section of the fluvial Seine estuary during high river flows.River-related sediment fluxes were estimated from the measurement of fine-grained sedimentation zones in the fluvial part of the estuary. The erosion/sedimentation processes were perennial, and the amounts of contributing sediments were directly related to the solid river load. Our results indicate that mudflats in the fluvial part of the Seine estuary play an important role in the downstream transfer of fine-grained suspended particulate matter (SPM) towards the turbidity maximum and the Rouen docks particularly during low river flows, when roughly 30–50% of the SPM originates from the eroded intertidal flats.  相似文献   

Morphodynamics and cobbles behavior in and near the surf zone     

S. I. Voropayev  F. Y. Testik  H. J. S. Fernando  D. L. Boyer 《Ocean Engineering》2003,30(14):1741-1764

The evolution of an initially flat sandy slope and the dynamics of large objects (cobbles/mines) emplaced on it are studied in a laboratory wave tank under simulated surf conditions. Upon initiation of wave forcing, the initially flat beach undergoes bedform changes before reaching a quasi-steady morphology characterized by a system of sand ripples along the slope and a large bar near the break point. Although the incoming wave characteristics are held fixed, the bottom morphology never reaches a strict steady state, but rather slowly changes due to the migration of ripples and bar transformation. When the wave characteristics are changed, the bedform adjusts to a new quasi-steady state after a suitable adjustment time. Studies conducted by placing model cobbles/mines on the evolving sandy bottom subjected to wave forcing show four distinct scenarios: (i) periodic cobble oscillations with zero mean displacement and small scour around the cobbles, (ii) mean onshore motion of relatively light cobbles, (iii) periodic burial of relatively heavy cobbles when their sizes are comparable to those of sand ripples, and (iv) the burial of relatively large cobbles under the bar, when the bar migrates due to changes of incoming waves. Quantitative data on the characteristics and dynamics of the bedform, including ripple-formation front propagating down the slope, ripple growth and drift, and flow around ripples, are presented. Physical explanations are provided for the observations.  相似文献   

Interannual variability of the Kuroshio transport passing through the 137°E meridian in an OGCM related to the North Pacific windstress     

Yoshinobu Wakata  Takashi Setou  Ikuo Kaneko  Hiroshi Uchida  Shiro Imawaki 《Journal of Oceanography》2006,62(1):25-35

The interannual variability of the Kuroshio volume transport passing through the 137°E meridian south of Japan was simulated with an ocean general circulation model (OGCM). The time series of the Kuroshio volume transport over the 1000 m depth in the OGCM is well reproduced by the one-dimensional quasi-geostrophic (QG) vorticity equation with a windstress forcing. In our analysis of the OGCM and QG results, we found that peaks and troughs of the time series of the Kuroshio volume transport with 2–3 yr time-scale were induced by windstress curl, both local and immediately eastward, whereas longer time-scale variability was also induced by windstress curl near the dateline.  相似文献