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91.
Hydrographic properties from CTD and discrete bottle sample profiles covering the Japan (East) Sea in summer, 1999, are presented in vertical sections, maps at standard depths, maps on isopycnal surfaces, and as property–property distributions. This data set covers most of the Sea with the exception of the western boundary region and northern Tatar Strait, and includes nutrients, pH, alkalinity, and chlorofluorocarbons, as well as the usual temperature, salinity, and oxygen observations.  相似文献   
92.
A Moored Underwater Energy Conservation System for Profiling Measurement   总被引:3,自引:0,他引:3  
There is a need to obtain the hydrologic data including ocean current,wave,temperature and so on in the South China Sea.A new profiling instrument which does not suffer from the damage due to nature forces or incidents caused by passing ships,is under development to acquire data from this area.This device is based on a taut single point mid-water mooring system.It incorporates a small,instrumented vertically profiling float attached via an electromechanical cable to a winch integral with the main subsurface flotation.On a pre-set schedule,the instrument float with sensors is winched up to the surface if there is no ship passing by,which is defined by an on-board miniature sonar.And it can be immediately winched down to a certain depth if the sonar sensor finds something is coming.Since,because of logistics,the area can only be visited once for a long time and a minimum of 10 times per day profiles are desired,energy demands are severe.To respond to these concerns,the system has been designed to conserve a substantial portion of the potential energy lost during the ascent phase of each profile and subsequently use this energy to pull the instrument down.Compared with the previous single-point layered measuring mode,it is advanced and economica1.At last the paper introduces the test in the South China Sea.  相似文献   
93.
The results obtained from an Ocean General Circulation Model (OGCM), the Modular Ocean Model 2.2, forced with the National Center for Environmental Prediction/National Center for Atmospheric Research reanalysis data, and observational data have been utilized to document the climatological seasonal cycle of the upper ocean response in the Tropical Indian Ocean. We address the various roles played by the net surface heat flux and the local and remote ocean dynamics for the seasonal variation of near-surface heat budget in the Tropical Indian Ocean. The investigation is based in seven selected boxes in the Arabian Sea, Bay of Bengal and the Equatorial Indian Ocean. The changes of basin-wide heat budget of ocean process in the Arabian Sea and the Western Equatorial Indian Ocean show an annual cycle, whereas those in the Bay of Bengal and the Eastern Equatorial Indian Ocean show a semi-annual cycle. The time tendency of heat budget in the Arabian Sea depends on both the net surface heat flux and ocean dynamics while on the other hand, that in the Bay of Bengal depends mainly on the net surface flux. However, it has been found that the changes of heat budget are very different between western and eastern regional sea areas in the Arabian Sea and the Bay of Bengal, respectively. This difference depends on seasonal variations of the different local wind forcing and the different ocean dynamics associated with ocean eddies and Kelvin and Rossby waves in each regional sea areas. We also discuss the comparison and the connection for the seasonal variation of near-surface heat budget among their regional sea areas. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
94.
热释光是矿物晶体接受环境核辐射作用后积蓄起来的能量在受到热激发时以光的形式释放出来的一种物理现象,它与晶体损伤、晶体中杂质混入等原因所导致的晶格缺陷有关.热释光强度的大小主要取决于自然界中长寿命放射性元素(238U,235U,230Th,40K及其子体)的衰变,与其他物理、化学、生物或人类活动无关.热释光特征能有效反映晶体形成的环境条件.热释光方法的制样简单、测量快捷,因此在辐射学、核工业、核医学、环境学、农业、考古学、地质学等领域都得到了广泛的应用.在陆地地质学上热释光方法在地质年代测定[1,2]、地层对比[3]、矿物世代划分[4]、矿床含矿评价[4,5]、陨石形成热的历史恢复[6]以及地质事件识别[7]等方面都取得了不少成果.  相似文献   
95.
Fluctuations of peak energy and peak frequency o local wavelet energy spectrum for wind wavesTXFluctuationsofpeakenergyandpeak...  相似文献   
96.
97.
东太平洋柱状沉积物的古气候和古环境记录   总被引:1,自引:2,他引:1  
太平洋深海盆地的远洋沉积物在物质组成和来源上远较大陆边缘简单.由于远离大陆,又有海沟与周边大陆分隔,太平洋深海沉积物中通常不包含由河流水系搬运而来的悬浮物,因此从深海沉积物中提取古气候、古环境信息可以避免诸多地质因素相互叠加和干扰[1].深海远洋沉积物中的主要组分是风成陆源碎屑(包括火山碎屑)和来自上层海水的生源组分(降落到洋底的生物壳体)以及由海解作用形成的自生矿物[2],其中陆源碎屑的相对含量、粒度及矿物成分可以反映大气环流的强度及物源区的气候环境[1],生源组分的组成、相对含量和丰度以及种属含量变化则与表层海水的生产力和溶解作用有关.  相似文献   
98.
Abstract-Heat content of the upper layer above the 20℃ isotherm in the tropical Pacific Ocean isestimated by using the sea temperature data set with a resolution 2°latitude×5°longitude (1980~1993)for the water depths (every 10 m) from 0 m to 400 m, and its temporal and spatial variabilities are an-alyzed. (1) The temporal variability indicates that the total heat in the upper layer of the equatorial Pa-cific Ocean is charcterized by the interannual variability. The time series of the equatorial heat anomaly5 months lead that of the El Nino index at the best positive lag correlation between the two, and theformer 13 months lag behind the latter at their best negative lag correlation. Therefore the equatorialheat content can be used as a better predictor than the El Nino index for a warm or cold event. In addi-tion, it is also found that less heat anomaly in the equator corresponds to the stronger warm events inthe period (1980~1993) and much more heat was accumulated in the 4 years including 1992/1  相似文献   
99.
减少航道外波浪集聚对策研究   总被引:3,自引:0,他引:3  
进港航道开挖引起波能重新分布 ,导致航道外近区域波能聚集 ,波高增大 ,从而影响防波堤稳定及港内泊稳条件。文章介绍了 Boussinesq方程的推导过程和发展过程 ,基于深水和缓变地形的色散关系 ,建立了波浪数学模型。该模型可用于研究深水和浅水地区波浪的浅水变形、折射、绕射和反射。并提出了减少波能聚集、降低堤前波高的多种措施。结合大窑湾港实际工程 ,经过多方面的数物模比选 ,利用数学模型优化出一种可行的喇叭口航道开挖方案并付诸实施 ,降低了防波堤的堤前波高 ,满足了预期的设计要求。  相似文献   
100.
本文根据1996年“中-法合作东海计划”在冲绳海槽中西部边缘区所取柱状样岩芯沉积物粒度分析资料,对该区沉积物特征进行研究。结果表明,火山沉积和富含生物的半远洋深海软泥沉积是本区的主要特征。以481cm为界,上、下两层沉积物截然不同,可能是沉积物的来源不同或者是水动力条件的差异。该区主要受火山活动的影响,其次是黑潮、大洋风暴  相似文献   
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