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Evolution of a coastal upwelling event during summer 2004 in the southern Taiwan Strait 总被引:3,自引:0,他引:3
A coastal upwelling event in the southern Taiwan Strait (STWS) was investigated using intensive cruise surveys (four repeated transects in a month) and satellite data in July and early August 2004.The extensive upwelling-associated surface cold water was first observed in early July (~2.0×10 4 km 2) along the STWS coast.Then,the cold surface water reduced in size by ~50% with decreased chlorophyll concentrations after 15 days,indicating the weakening of the upwelling event.At the end of July,the cold surface water disappeared.The temporal variations of the surface cold water and the 3-D hydrography around Dongshan Island are thought to be mainly attributed to the weakened upwelling-favorable southwestern wind,the asymmetric spatial structure of the wind field and the intrusion of warm water from the northern South China Sea. 相似文献
64.
Responses of governance systems to change in coastal and marine ecosystems vary from country to country around the globe. Lessons can be learned from country specific case studies, as national governments strive to adapt and respond to issues of concern. This short paper highlights the benefits of a country-specific, special edition of Marine Policy, with a focus on Ireland. Despite the uniqueness of socio-ecological setting, many of the issues faced by policy makers in Ireland, such as the reconciliation of economic development and conservation needs, are shared elsewhere. This special edition was produced at the end of the ‘Celtic Tiger’ in Ireland. As a result, it reflects an era when economic development was very much a priority. The same period represented an unparalleled investment in marine science since the foundation of the State in 1922. Despite this, the papers in the Special Edition point to varying degrees of progress in policy integration and implementation. Papers covering a range of sectors (fisheries, ocean energy, conservation and fisheries) and disciplines (economics, science and management) will be of interest to academics, policy makers, students and practitioners of marine policy. 相似文献
65.
For the study of the parametric vibration response of submerged floating tunnel tether under random excitation,a nonlinear random parametric vibration equation of coupled tether and tube of submerged floating tunnel is set up.Subsequently,vibration response of tether in the tether-tube system is analyzed by Monte Carlo method.It may be concluded that when the tube is subjected to zero-mean Gaussian white noise random excitation,the displacement and velocity root mean square responses of tether reach the peak if the circular frequency of tube doubles that of tether;the displacement and velocity root mean square responses of tether increase as the random excitation root mean square increases;owing to the damping force of water,the displacement and velocity root mean square responses of tether decrease rapidly compared with tether in air;increasing the damping of the tether or tube reduces the displacement and velocity root mean square responses of tether;the large-amplitude vibration of tether may be avoided by locating dampers on the tether or tube. 相似文献
66.
D. Franke U. BarckhausenN. Baristeas M. EngelsS. Ladage R. LutzJ. Montano N. PellejeraE.G. Ramos M. Schnabel 《Marine and Petroleum Geology》2011,28(6):1187-1204
The South China Sea formed by magma-poor, or intermediate volcanic rifting in the Paleogene. We investigate the structure of the continent-ocean transition (COT) at its southern margin, off NW Palawan between the continental blocks of Reed Bank and the islands of Palawan and Calamian. Several surveys, recorded by the BGR from 1979 to 2008, established a comprehensive database of regional seismic lines, accompanied with magnetic and gravity profiles.We interpret two major rifted basins, extending in the NE direction across the shelf and slope, separated by a structural high of non volcanic origin.The continent-ocean transition is interpreted at the seaward limit of the continental crust, when magnetic spreading anomalies terminate some 80-100 km farther north. The area in between displays extensive volcanism - as manifest by extrusions that occasionally reach and cut the seafloor, by dykes, and by presumed basaltic lava flows - occurring after break-up.The COT is highly variable along the NW Palawan slope: One type shows a distinct outer ridge at the COT with a steep modern seafloor relief. The other type is characterised by rotated fault blocks, bounded by listric normal faults ramping down to a common detachment surface. Half-grabens developed above a strongly eroded pre-rift basement. The seafloor relief is smooth across this other type of COT.We suggest the pre-rift lithospheric configuration had major influence on the formation of the COT, besides transfer zones. Volcanic domains, confined to the north of competent crustal blocks correlate with the style of the COT.Gravity modelling revealed an extremely thinned crust across the shelf. We propose a depth-dependent extension model with crust being decoupled from mantle lithosphere, explaining the discrepancy of subsidence observed across the South China Sea region. 相似文献
67.
利用3s技术强大的空间信息处理和管理能力及制图能力,实现了在海南省海岸保护利用规划中多源地理数据采集处理、专题信息分析提取、规划图集编制和规划信息管理系统的建立等.结果表明:采用3S技术能够较好地处理海南省海岸保护利用规划中涉及的陆图、海图、遥感图、海洋功能区图、相关规划图和项目用海图等基础地理数据,以及现场调查、勘测数据的空间位置关系;提取了海南岛海岸类型、海岸开发利用现状等专题信息;结合海南社会经济发展对海岸资源开发利用的需求和生态环境保护要求,划分基本功能岸段,总体为北部海岸以港口、旅游岸段为主,东部海岸以旅游、渔业岸段为主,南部海岸以旅游、港口岸段为主,西部海岸以港口、渔业岸段为主. 相似文献
68.
大洋海区海-气CO_2通量单参数遥感算法的适用性检验 总被引:1,自引:0,他引:1
利用卫星遥感技术的优势,基于LDEO数据库的全球海表二氧化碳分压(PCO2)及海表温度(SST)等实测数据,初步建立东太平洋海区PCO2与SST的单参数经验算法,并采用相同区域的独立实测数据检验.结果表明,单参数算法在寡营养大洋海区具有良好的适用性,反演值与实测值之间的均方根误差(RMS)为0.51 Pa(1 Pa=9.869μatm),由此估算出2003年6月该海域CO2通量为-1.4 mmol/(m2.d),与实测估算的碳通量基本相符,能够很好地反映出海区CO2源汇特征.将该遥感算法运用到西大西洋海域(15°~25°N,60°~75°W),反演值与实测值之间均方根误差(RMS)为0.69 Pa.检验结果表明,在寡营养大洋海区,单参数遥感算法具有一定的适用性,在受相似因子调控的同纬度海区可以使用同一遥感算法. 相似文献
69.
海洋标准评估方法研究 总被引:2,自引:0,他引:2
科学评估海洋标准是提高海洋标准质量的重要手段.分析了影响海洋标准评估因素确定的条件,建立海洋标准评估指标体系与评价集.利用层次分析法和模糊综合评价法对海洋标准进行评估,定量评估了海洋标准的质量.该方法为建立科学的、操作性强的标准评估体系提供研究基础,有利于完善对海洋标准质量的控制,提高海洋标准的管理水平. 相似文献
70.
球体模型系统是目前GIS领域的研究热点,它以强大的空间数据管理能力,丰富直观的信息表现能力迅速成为空间信息集成共享的有力平台.以Skyline软件平台为基础,介绍了数字海洋可视化系统的体系架构、功能设计和技术实现方法.实践应用表明,该系统在多源海洋信息可视化集成共享方面具有良好的应用前景. 相似文献