长江河口理论最高和最低潮面计算和应用     

林唐宇  朱建荣 《海洋工程》2013,31(2):82-87

应用改进的河口海洋数值模式,计算长江河口及其邻近海域水位随时间的变化,利用国际上先进的T_Tide调和常数软件计算得出潮汐的主要调和常数,根据《海道测量规范》(GB12317—1998)理论最低、最高潮面算法,在考虑8个主要分潮M2、S2、N2、K2、K1、O1、P1、Q1的基础上再考虑3个主要浅水分潮M4、M6和MS4,得出长江河口理论最低、最高潮面的空间分布。采用数值模式,设计高分辨的网格,有效解决了潮位站稀少和空间分布不均的不足,提升了理论最低、最高潮面的计算精度。将基于理论最低潮面的2009年长江河口实测地形资料转化为基于85国家高程基面的地形资料,使资料得到了充分应用。  相似文献   

海平面上升背景下上海市长江口水源地供水安全风险评估及对策     

程和琴  塔娜  周莹  朱建荣  阮仁良  陈吉余 《气候变化研究进展》2015,11(4):263-269

分析和甄别上海市需水系统和长江口水源地供水系统风险因子,建立基于水资源供需平衡的上海市水源地供水安全风险评估模型,并采用系统动力学预测模型和高分辨率非正交曲线网格移动潮滩边界的长江河口盐水入侵三维数值模型,分别计算分析2030年人口增长、径流减少和海平面上升等3种风险因子叠加作用下的上海市需水量与长江口陈行、东风西沙和青草沙3个水源地的可供原水量,并进行供需比较分析和供水安全风险评估。结果表明：在海平面分别上升10和25 cm、枯季平均径流和没有新增水源条件下,2020年的缺水量分别为39万和74万m³/d,特枯水文年供水能力降低19万m³/d;若新增没冒沙水源300万m³/d,可缓解上海市2020年的缺水状况。  相似文献   

河口最大浑浊带形成的动力模式和数值试验   总被引：8，自引：0，他引：8  

朱建荣  傅德健吴辉 戚定满 《海洋工程》2004,22(1):66-73

应用改进的ECOM模式,耦合泥沙输运模型,研究理想河口最大浑浊带形成的动力机制。河口最大浑浊带位于滞流点处,上下游余流均向该处输运泥沙,造成该处泥沙汇合,而由流场辐合产生的上升流又使该处的泥沙不易落淤。南岸(河口东向)的泥沙浓度比北岸高,最大浑浊带位于南岸,这是由于盐水入侵带来的高盐水位于北岸的底层,其斜压效应使底层的环流由北向南流动,把底层高浓度的泥沙向南岸平流,聚集于南岸底层。除上游河流泥沙来源外,强大的涨落潮流冲刷床面,使沉降于床面的泥沙再次悬浮,成为余流输运泥沙的来源之一。  相似文献   

径流量和海平面变化对河口最大浑浊带的影响   总被引：2，自引：0，他引：2  

朱建荣  戚定满  肖成猷  吴辉 《海洋学报》2004,26(5):12-22

应用改进的ECOM模式,耦合泥沙输运方程,研究径流量和海平面变化对河口最大浑浊带的影响.河口最大浑浊带位于滞流点处,底层上下游余流均向该处输运泥沙,造成该处泥沙汇合,而由流场辐合产生的上升流又使该处的泥沙不易落淤.由于盐水入侵带来的高盐水位于北岸的底层,其斜压效应使底层的横向环流由北向南流动,把底层高浓度的泥沙向南岸平流,使得最大浑浊带位于南岸.研究河口最大浑浊带现象必须使用三维泥沙输运模式.在径流量增大的情况下,与控制试验相比底层向陆的密度流减弱,滞流点下移,导致最大浑浊带也下移;因上游来沙量增加,在最大浑浊带中心和河口拦门沙处悬浮泥沙浓度趋于增加.在径流量减少的情况下,最大浑浊带的变化趋势与径流量增大情况的结果相反.在海平面上升的情况下,拦门沙区域底层向陆的密度流趋于增强,滞流点上移,最大浑浊带也相应向上游移动;最大浑浊带中心处泥沙浓度趋于增大,但口门拦门沙处泥沙浓度趋于减小.径流量和海平面变化对最大浑浊带影响明显.  相似文献   

采用质点跟踪方法对物质输运方程平流项数值格式的改进   总被引：1，自引：1，他引：0       下载免费PDF全文

陈昞睿  朱建荣  戚定满 《海洋与湖沼》2008,39(5):439-445

用数值模式对河口海岸地区的物质输运进行计算时，平流项的数值格式必须要能对物质浓度锋面进行正确处理，以避免产生过多的数值耗散或频散。本文中设计了一种在网格内设置一些质点并对质点进行跟踪的格式计算平流项。结果表明，质点跟踪格式在一维情形下无频散和几乎没有耗散，在二维情形下无频散和在水深变化剧烈的地方基本避免了垂向数值耗散。与其他数值格式的耗散性和频散性相比，本文中设计的数值格式明显地提高了物质输运方程中平流项的计算精度，在河口海洋物质输运的计算中具有较大的应用价值。  相似文献   

Observed residual currents off the Changjiang （Yangtze） Rivermouth in wintertime of 1959 and 1982   总被引：1，自引：0，他引：1  

朱建荣胡敦欣  肖成猷 《中国海洋湖沼学报》2004,22(3):244-249

Data taken in the two large-scale ocean investigations in China in winter 1959 and 1982 are used to analyze the residual current off the Changjiang (Yangtze) River mouth in this paper. The current in wintertime off the river mouth consist of the Changjiang runoff, wind-driven current, coastal current, density-driven current and Taiwan Warm Current (TWC). The TWC occurs in wintertime off the mouth. The surface TWC reaches only to the east side of Dinghai, then turns southeastward. The bottom TWC can flow to the area off the Changjiang mouth along west slop of the submerged river valley (SRV) and to the area off the Subei coast, The simulated currents by 3D model are basically consistent with the observed currents, although the model was run with climatological forces and the observations was done in episodic time manner.  相似文献   

Dispersal and fate of dredged materials disposed of in the Changjiang Estuary determined by use of an in situ rare earth element tracer     

刘高峰  吴华林  郭文华  朱建荣  孙连成 《中国海洋工程》2011,25(3):495-506

To investigate the dispersal pattern and the fate of dredged materials disposed at a pre-selected disposal site, a field tracer experiment was conducted in the North Passage of the Changjiang Estuary during the 2005 flood season. Three tons of dredged materials were mixed with 2.792 kg of sodium hexachloroiridate (IV) hexahydrate (SHH), which contained the rare earth element tracer iridum (Ir). Sampling was conducted at pre-selected sections of the estuary on the second, third and fourth day after the release of dredged materials. All samples were evaluated by use of neutron activation analysis. The majority of the dredged material was dispersed nearly parallel to the navigation channel and deposited between the channel and the south dike. Only a small quantity of dredged materials entered or crossed the navigation channel, and the back silting ratio in the navigation channel was about 5%. The dredged materials also dispersed southeasterly beyond two dike heads.  相似文献   

长江河口涨落潮不对称性动力成因分析   总被引：6，自引：3，他引：3       下载免费PDF全文

王彪  朱建荣  李路 《海洋学报》2011,33(3):19-27

长江河口存在着涨落潮流速和历时的不对称现象.本应用长江河口三维数值模式,数值试验定量给出了不同径流量、潮汐和水深下南北支、南北港和南北槽涨潮落潮平均流速和历时,通过横断面涨潮落潮通量必须满足质量守恒观点从动力机制上给出了涨潮落潮流速和历时不对称的成因.  相似文献   

Simulated circulations off the Changjiang （Yangtze） River mouthin spring and autumn   总被引：1，自引：0，他引：1  

朱建荣戚定满  肖成猷 《中国海洋湖沼学报》2004,22(3):286-291

The circulations off the Changjiang mouth in May and November were simulatedby a three dimension numerical model with monthly averaged parameters of dynamic factors in this paper. The area covers the East China Sea (ECS), Yellow Sea and Bohai Sea. Simulated results show that the circulation off the Changjiang mouth in spring and autumn is mainly the Changjiang runoff and Taiwan Warm Current (TWC). The Changjlang discharge is much larger in May than in November, and the wind is westward in May, and southward in November offthe Changjiang mouth. The runoff in May branches in three parts, one eastward flows, the other two flow northward and southward along the Subei and Zhejiang coast respectively. The Changjiang diluted water expands eastward off the mouth, and forms a strong salinity front near the mouth. Surface circulation in autumn is similar to that in winter, the runoff southward flows along the coast, and the northward flowing TWC becomes weaker compared to that in spring and summer. The bottom circulations in May and November are mainly the runoff near the mouth and the TWC off the mouth, and the runoff and TWC are greater in May than in November.  相似文献   

A numerical study on water diversion ratio of the Changjiang(Yangtze)estuary in dry season   总被引：3，自引：0，他引：3  

李路  朱建荣  吴辉  王彪 《中国海洋湖沼学报》2010,(3)

We studied the flood, ebb and tidal averaged along (net) water diversion ratio (WDR) during dry season in the Changjiang (Yangtze) estuary, China, along with the effects of northerly wind, river discharge, tide and their interactions on WDR using the improved version of three-dimensional numerical model ECOM. Using data for annual mean wind speed and river discharge during January, we determined that the flood, ebb, net WDR values in the North Branch of the estuary were 3.48%, 1.68%,-4.06% during spring tide, and 4.82%, 2.34%,-2.79% during neap tide, respectively. Negative net WDR values denote the transport of water from the North Branch into the South Branch. Using the same data, the corresponding ratios were 50.09%, 50.92%, 54.97%, and 52.33%, 50.15%, 43.86% in the North Channel and 38.56%, 44.78%, 103.96%, and 36.92%, 43.17%, 60.97% in the North Passage, respectively. When northerly wind speed increased, landward Ekman transport was enhanced in the North Branch, increasing the flood WDR, while the ebb WDR declined and the net WDR exhibited a significant decrease. Similarly, in the North Channel, the flood WDR is increased, the ebb WDR reduced, and the net WDR showed a marked decrease. In the North Passage, the flood WDR also increased while the ebb and net WDR declined. As the river discharge increased, the flood and ebb WDR of the North Branch increased slightly and the net WDR increased markedly. In the North Channel the flood and ebb WDR changed very slightly, while the net WDR declined during spring tides and increased during neap tides. The WDR in the North Passage changed slightly during flood and ebb tides while the net WDR showed a marked increase. The WDR values of different bifurcations and the responses to northerly wind, river discharge, and tide are discussed in comparison with variations in river topography, horizontal wind-induced circulation, and tidal-induced residual current.  相似文献