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1.
黄河口附近水文特征分析 总被引：8，自引：0，他引：8
The Huanghe River is the second largest river in our country. The average annual runoff at the estuary is 44.28 billion cubic meters, the average annual suspended load is 1.12 billion tons, of which 24% was deposited on the delta, 40% on the coast and the rest 36% is considered to be carried into the deep sea by various dynamic factors. We‘ve measured the temperature, salinity, current and suspended load in the estuary from autumn of 1983 to summer of 1984 for building a harbour in future. According to our data and other historical data from some institutes, we‘ve obtained following conclusions: 1) The distribution of temperature in winter is different with from that in summer: the contours of temperature in winter is parallel to coast line,and the contours of temperature in summer is coincident with latitudes. 2) The salinity in summer is lower than that in winter. There are three tongues of low values of salinity at the estuary in summer. They are pointed to North,North-east and South-east respectively. Only two tongues are appeared in winter-northward and south-eastward. 3) The distribution of suspended load is similar to the distribution of salinity,There are three tongues of high values of suspended load at the estuary in summer, they are pointed to North,North-east and Southeast respectively,the quantity of suspended load per litre in winter is much than in summer. 4) The influence of Huanghe River to North area of the estuary is less than to Laichou Bay. 5) The velocities of tide current at the estuary are very large.The maximum value is about 150era/see, and the directions of tide current are parallel to coastline. 相似文献
2.
西沙群岛潮、余流特征研究 总被引：1，自引：0，他引：1
对1962、1974、1976、1991、2002年西沙群岛海域实测海流资料分析得出:西沙群岛潮汐特征系数为3.40,是不正规日潮;潮流特征比较复杂,少数为不规则半日潮流型,多数为不规则日潮流型;半日周期的内潮在永兴岛西部特别显著,最大流速可达1.5m/s,对珊瑚生态系统有重要影响;西沙群岛余流,春季4～5月总体方向是东北,最大余流速度66cm/s,出现在中建岛西部;夏初余流方向偏北,速度明显降低,中建岛表、底层流速都不超过50cm/s。结合18a卫星高度计资料统计分析得出,春季和夏季西沙群岛海域处于反气旋式环流的北部,中建岛处于反气旋式环流的西缘,水平压强梯度大,加之地形影响,因此流速最大。 相似文献
3.
根据夏季琼州海峡新海附近15 m处地层潮流谱分析结果可得,无论是f>0 或f<0,全日潮谱峰都高于半日潮谱峰。其中,半日潮周期,约为12 h,12.4 h,日潮存在两个,一个在23.9 h,另一个在25.8 h前后;在半日潮和全日潮分量中,反时针分量是主要的、顺时针的日潮能谱只有反时针的84%;顺时针的半日潮能谱只有反时针的63%;浅水分潮8.3 h,6.2 h和超过24 h的4.2 d,3 d等也很明显,但是未通过显著性检验; 大多数余流流速在5~10 cm/s之间,个别情况超过40 cm/s。受反时针运动涡旋影响,余流主要向偏东北、北、西北方向运动。在这个区间内的流向,占总观测数68%以上;风对余流也有重要影响:东北风将使余流方向偏向西北,偏北向风将使余流方向偏南。 相似文献
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The Luzon Strait is the only deep channel that connects the South China Sea(SCS) with the Pacific.The transport through the Luzon Strait is an important process influencing the circulation,heat and water budgets of the SCS.Early observations have suggested that water enters the SCS in winter but water inflow or outflow in summer is quite controversial.On the basis of hydrographic measurements from CTD along 120° E in the Luzon Strait during the period from September 18 to 20 in 2006,the characteristics of t... 相似文献
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黄河是我国第二条大河,多年平均年迳流量442.8亿立米,挟带入海沙量近11亿吨,以水少沙多闻名于世界。自1855年从苏北改造注入渤海以来,河口三角洲岸线不断外移。据庞家珍、司书亨的研究结果,在1855—1954年间,造陆速率为23平方公里/年,平均岸线外延速率为0.15公里/年;1954—1972年间,造陆速率为23.5平方公里/年,平均岸线外延速率为0.42公里/年,造陆速率基本未变,只是因河口范围缩小,致使河口外延速率增加。 相似文献
9.
The action of the wind field and the influence of topography can cause divergence or convergence of surface current. The existence of the divergence-convergence effect is proved and the dynamical significance of the divergent or convergent state and its link with many marine phenomena are pointed out. Divergence fields of surface current in the Bohai Sea in winter and summer are obtained by numerical modelling describing the divergence-convergence character of seasonally wind-driven current. The relation between the effect and seasonal marine phenomena is discussed. Study on the divergence-convergence effect of surface current (DCESC)can be an indirect method for testing the calculated results. 相似文献
10.
Nonlinear numerical models of continuously stratified seas are developed for vertical sections to study the mechanism of coastal upwelling and coastal jets in two kinds of seas: the so-called finite or closed sea bounded by two vertical coastal coasts, without elevation of sea surface, but with a flat bottom; and the semi-infinite sea bounded by only one vertical coast, with both an elevation of sea surface and a flat or inclined bottom. Constant wind stress in the first case, and constant wind stress or negative wind stress curl in the second case, are abruptly imposed. The key procedure for the mathematical analysis is to calculate the horizontal pressure gradient first by a special treatment. In thefirst case, the variation of horizontal components of velocity is changed with time to show threesuccessive time intervals. The results show that the width of baroclinic jets depends upon (oS)1/2, andthat distribution of isopycnic lines delineates the warm and cold regions. The relative importance of each 相似文献
