黄河口附近水文特征分析

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。     

1998年夏季南海水团分析

根据 1 998年夏季“南海季风试验 ( SCSMEX)”期间所获的 CTD资料 ,使用系统聚类、Fuzzy模式聚类、Bayes判别分析和 Fuzzy分析等水团分析方法 ,对南海水体的结构和水团配置状况等进行了分析 ,划出了南海存在的 9个主要水团 ,并对各水团的温、盐度特征进行了初析。在调查期间 ,南海本地水 (南海水 )几乎控制了整个调查海区 ,而黑潮水仅出现在台湾岛的西南海域 ;海水强烈混合发生在吕宋海峡附近 ;在中南半岛以东和吕宋岛以西海域 ,表层水明显下沉 ;在南海东南部可能有来自苏禄海的海水 ,其温、盐度特征类似于吕宋海峡中的黑潮水     

广西主要港湾余流特征及其对物质输运的影响

广西5个主要海湾各有自己的环流特征：铁山湾存在一个反气旋涡，廉州湾存在一个海湾尺度的气旋环流，钦州湾青菜头南端存在一个气旋式环流，防城湾口有一个气旋环流。珍珠湾余流，在深水航道内自湾内指向湾外。冬季，受北风影响，各湾从湾内流向湾外的余流分量加强。由于反气旋或气旋环流存在，形成和环流相应的泥沙输运。     

THE DIVERGENCE-CONVERGENCE EFFECT OF SURFACE CURRENT AND ITS ACTION ON THE BOHAI SEA

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.     

COASTAL UPWELLING AND COASTAL JETS IN CONTINUOUSLY STRATIFIED SEAS

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     

琼东沿岸上升流二维数值模型的诊断计算

我国沿岸有两大上升流区域,其一在浙江沿岸.迄今为止,对其形成机制、时空变异等,已经进行了较多的定性及定量研究.     

海南新海夏季潮流谱分析和余流研究

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。     

钦州湾潮流特征分析

根据1994年5月和11—12月两个航次的调查及近年有关海湾的海流观测资料，分析了钦州湾的潮流特征，观测资料来自分布于该海湾东中西三个航道及相关区域的8个测站。钦州湾涨落潮流特征：落潮流速大于涨潮流速：东部最大涨落潮流速小于西部：夏季落潮流总是大于冬季：龙门水道附近的流速最大，而其余区域的流速相对较小。外湾(钦州湾)余流，是气旋式环流：水体东进而西出。从湾内来的泥沙和污染物质，主要从西部进入外海；中、东槽是主要“进水”通道，外海低泥沙含量、少污染物质的清洁水从这里潮流而上。因此，与西部相比，东部盐度高，水质清洁，底质重金属含量少。     

黄河口附近水文特征分析

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.