Surface circulation of the Levantine Basin: Comparison of model results with observations   总被引：1，自引：1，他引：1  

B. Alhammoud  K. Branger  L. Mortier  M. Crpon  I. Dekeyser 《Progress in Oceanography》2005,66(2-4):299

The eastern Mediterranean (Levantine Basin) hydrography and circulation are investigated by comparing the results of a high-resolution primitive equation model with observations. After a 10-year integration, the model is able to reproduce the major water masses and the circulation patterns of the eastern Mediterranean. Comparisons with the POEM hydrographical observations show good agreement. The vertical distribution of the water masses matches that of the observations quite well in terms of monthly mean. The model surface circulation is in agreement with circulation schemes derived from recent observations. Some well-known mesoscale features of the upper thermocline circulation are also realistically reproduced. In agreement with satellite observations, the model shows that high-energy mesoscale eddies dominate the upper thermocline circulation in the southern and the central parts of the Levantine Basin. Most of the Atlantic Water follows the north African coast and forms a strong coastal jet near the Libyan coast rather than forming the Mid-Mediterranean Jet described by several authors. The sub-basin circulation shows a strong seasonal signal. A strong and stable current flows along the isobaths in winter, becoming weaker and with more meanders in summer. The mesoscale eddies throughout the whole basin are more energetic in summer than in winter.  相似文献   

Extremely Shallow-water Morphobathymetric Surveys: The Valle Fattibello (Comacchio, Italy) Test Case     

Luca Gasperini 《Marine Geophysical Researches》2005,26(2-4):97-107

  相似文献   

冬季东中国海环流中的中尺度涡旋数值模拟   总被引：5，自引：0，他引：5       下载免费PDF全文

陈敏  侯一筠  赵保仁 《海洋科学》2003,27(1):53-60

采用高精度的POM模式 ,考虑了海底地形、外来流、长江径流、海面风应力、海面热通量等多方面因素的影响 ,模拟了冬季东中国海环流结构。模拟结果显示 :在黄海东部很可能存在两个涡 ,中心分别在124°37′E ,37°N ,124°E ,35°30′N ;东海北部存在一个大型的气旋式涡旋 ,其中心位置在125.1°E ,30.5°N附近 ,该涡旋是由东北向的台湾暖流、西北向的黄海暖流及南下的沿岸流组成的封闭结构 ;日本九州以西黑潮入侵分支形成一涡旋 ,黑潮分支是形成此涡旋的直接动力因素 ,另外地形和冬季盛行的偏北风也对该涡旋的形成有一定正面影响。  相似文献   

盐田水体遥感分类方法研究   总被引：3，自引：1，他引：3  

王晶晶  张鹰  陶菲 《海洋技术学报》2005,24(1):67-71

以连云港台北盐场为研究区，介绍了监督分类法和神经网络分类法及其在盐田水体遥感分类中的具体应用。研究结果表明，用神经网络分类法进行遥感影像自动分类，其分类精度高，显示了其在遥感领域较为广阔的应用前景。  相似文献   

长期天气预报中有关预报因子的若干探讨   总被引：3，自引：0，他引：3  

向元珍  曾九芳 《海洋预报》1995,12(2):1-11

目前行之有效的长期天气预报方法都是数理统计方法。本文以江淮流域夏季旱涝的长期预报为例，对有关预报因子的几个问题作了探索。挑选有实际天气学意义、各自独立、单相关系数较高的物理因子作预报因子，更有利于提高预报准确率，预报因子的时间尺度以月、季平均值最为适宜，而以三个旬滑动平均值的效果最佳，建立各种预报量的初选、精选因子库，更适用于计算机技术制作长期预报。  相似文献   

二阶不稳定型中立型微分方程解的振动准则     

张尊国 《中国海洋大学学报(自然科学版)》1991,(1)

改进不稳定型二阶中立型微分方程的最后结果,进一步研究该类方程解的振动条件。  相似文献   

海水中液-固界面的台阶型动力学曲线 Ⅱ.液膜扩散-递进扩散-界面分级交换反应联合控制的复合模型理论     

刘莲生  张正斌  蔡卫君  潘纲  杜恒清 《海洋与湖沼》1993,24(5):477-484

为定量解释海水中液-固界面的台阶型动力学曲线及其台阶的消长变化规律,在我们已提出的“液膜扩散和递进液膜扩散控制的复合模型”和“海水中液-固界面分级离子/配位子交换理论”基础上,吸取Crank的若干数学处理方法,进而提出适合于非稳态体系的“液膜扩散-递进扩散-界面分级交换反应联合控制的复合模型”。  相似文献   

南海西南部新生代盆地类型及演化历史   总被引：4，自引：0，他引：4  

钟广见  王Liao亮 《海洋湖沼通报》1996,(2):24-32

南海西南部地区发育了多种类型的新生代沉积盆地，各种类型的盆地具有各自的结构特征和演化历史，走滑－周缘前陆盆地－曾母盆地发育了渐新－中中新统层系，晚中新统层系和上新－第四系层系第三套地层，曾母盆地经历了三个发育阶段，拉张剪切盆地－万安盆地发育下第三系－下渐新统层系，上渐新统一中中新统层系和上中新统一第四系层系三套地层，万安盆地经历了四个发育阶段。  相似文献   

Circulation and currents in the southwestern East/Japan Sea: Overview and review     

K.-I. Chang  W.J. Teague  S.J. Lyu  H.T. Perkins  D.-K. Lee  D.R. Watts  Y.-B. Kim  D.A. Mitchell  C.M. Lee  K. Kim 《Progress in Oceanography》2004,61(2-4):105

A review is made of circulation and currents in the southwestern East/Japan Sea (the Ulleung Basin), and the Korea/Tsushima Strait which is a unique conduit for surface inflow into the Ulleung Basin. The review particularly concentrates on describing some preliminary results from recent extensive measurements made after 1996. Mean flow patterns are different in the upstream and downstream regions of the Korea/Tsushima Strait. A high velocity core occurs in the mid-section in the upstream region, and splits into two cores hugging the coasts of Korea and Japan, the downstream region, after passing around Tsushima Island located in the middle of the strait. Four-year mean transport into the East/Japan Sea through the Korea/Tsushima Strait based on submarine cable data calibrated by direct observations is 2.4 Sv (1 Sv = 10⁶ m³ s⁻¹). A wide range of variability occurs for the subtidal transport variation from subinertial (2–10 days) to interannual scales. While the subinertial variability is shown to arise from the atmospheric pressure disturbances, the longer period variation has been poorly understood.Mean upper circulation of the Ulleung Basin is characterized by the northward flowing East Korean Warm Current along the east coast of Korea and its meander eastward after the separation from the coast, the Offshore Branch along the coast of Japan, and the anticyclonic Ulleung Warm Eddy that forms from a meander of the East Korean Warm Current. Continuous acoustic travel-time measurements between June 1999 and June 2001 suggest five quasi-stable upper circulation patterns that persist for about 3–5 months with transitions between successive patterns occurring in a few months or days. Disappearance of the East Korean Warm Current is triggered by merging the Dok Cold Eddy, originating from the pinching-off of the meander trough, with the coastal cold water carried Southward by the North Korean Cold Current. The Ulleung Warm Eddy persisted for about 20 months in the middle of the Ulleung Basin with changes in its position and spatial scale associated with strengthening and weakening of the transport through the Korea/Tsushima Strait. The variability of upper circulation is partly related to the transport variation through the Korea/Tsushima Strait. Movements of the coastal cold water and the instability of the polar front also appear to be important factors affecting the variability.Deep circulation in the Ulleung Basin is primarily cyclonic and commonly consists of one or more cyclonic cells, and an anticyclonic cell centered near Ulleung Island. The cyclonic circulation is conjectured to be driven by a net inflow through the Ulleung Interplain Gap, which serves as a conduit for the exchange of deep waters between the Japan Basin in the northern East Sea and the Ulleung Basin. Deep currents are characterized by a short correlation scale and the predominance of mesoscale variability with periods of 20–40 days. Seasonality of deep currents is indistinct, and the coupling of upper and deep circulation has not been clarified yet.  相似文献   

南海西沙西南海域表层沉积物特征   总被引：3，自引：1，他引：3  

邱燕  姚伯初 《海洋地质与第四纪地质》1997,17(4):41-53

西沙西南海域表层沉积物样品矿物成分，地球化学，微体古生物分析测试结果表明：沉积物可分为７种类型，沉积环境主要是陆坡，部分为深海平原，海洋生物，海洋化学以及火山物质的沉积起到了积极的作用，陆源物质的影响较小，它们主要来源于北部大陆和南部岛礁等物源区。  相似文献