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Noise level in a marine environment has raised extensive concern in the scientific community. The research is carried out on i4Ocean platform following the process of ocean noise model integrating, noise data extracting, processing, visualizing, and interpreting, ocean noise map constructing and publishing. For the convenience of numerical computation, based on the characteristics of ocean noise field, a hybrid model related to spatial locations is suggested in the propagation model. The normal mode method K/I model is used for far field and ray method CANARY model is used for near field. Visualizing marine ambient noise data is critical to understanding and predicting marine noise for relevant decision making. Marine noise map can be constructed on virtual ocean scene. The systematic marine noise visualization framework includes preprocessing, coordinate transformation interpolation, and rendering. The simulation of ocean noise depends on realistic surface. Then the dynamic water simulation gird was improved with GPU fusion to achieve seamless combination with the visualization result of ocean noise. At the same time, the profile and spherical visualization include space, and time dimensionality were also provided for the vertical field characteristics of ocean ambient noise. Finally, marine noise map can be published with grid pre-processing and multistage cache technology to better serve the public. 相似文献
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陆源入海排污口是主要的海洋污染源之一,陆源入海排污口调查是海洋环境监测的重要内容。故此,针对陆源入海排污口监测与评价的业务需求,参照现行"陆源入海排污口及邻近海域生态环境监测指南"(HY/T086-2005), 在综合考虑各类卫星传感器应用能力与经济性的基础上,研究提出了一种利用多尺度卫星遥感数据对陆源入海排污口监测的方法。通过中分辨率卫星遥感数据的水质参数反演,结合水体光谱特征,进行渤海海域水质评价,划分重点监测区域,再利用高分辨率遥感影像,进行排污口的解译与制图。试验结果表明,该方法可以准确识别陆源入海排污口的分布及污染类型,对该区环境整治具有深远科学意义。 相似文献
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The newly developed Coupled Ocean-Atmosphere-Wave-Sediment Transport(COAWST) Modeling System is applied to investigate typhoon-ocean interactions in this study. The COAWST modeling system represents the state-of-the-art numerical simulation technique comprising several coupled models to study coastal and environmental processes. The modeling system is applied to simulate Typhoon Muifa(2011), which strengthened from a tropical storm to a super typhoon in the Northwestern Pacific, to explore the heat fluxes exchanged among the processes simulated using the atmosphere model WRF, ocean model ROMS and wave model SWAN. These three models adopted the same horizontal grid. Three numerical experiments with different coupling configurations are performed in order to investigate the impact of typhoon-ocean interaction on the intensity and ocean response to typhoon. The simulated typhoon tracks and intensities agree with observations. Comparisons of the simulated variables with available atmospheric and oceanic observations show the good performance of using the coupled modeling system for simulating the ocean and atmosphere processes during a typhoon event. The fully coupled simulation that includes a ocean model identifies a decreased SST as a result of the typhoon-forced entrainment. Typhoon intensity and wind speed are reduced due to the decrease of the sea surface temperature when using a coupled ocean model. The experiments with ocean coupled to atmosphere also results in decreased sea surface heat flux and air temperature. The heat flux decreases by about 29% compared to the WRF only case. The reduction of the energy induced by SST decreases, resulting in weakening of the typhoon. Coupling of the waves to the atmosphere and ocean model induces a slight increase of SST in the typhoon center area with the ocean-atmosphere interaction increased as a result of wave feedback to atmosphere. 相似文献
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In this study,a 3D virtual reality and visualization engine for rendering the ocean,named VV-Ocean,is designed for marine applications.The design goals of VV-Ocean aim at high fidelity simulation of ocean environment,visualization of massive and multidimensional marine data,and imitation of marine lives.VV-Ocean is composed of five modules,i.e.memory management module,resources management module,scene management module,rendering process management module and interaction management module.There are three core functions in VV-Ocean:reconstructing vivid virtual ocean scenes,visualizing real data dynamically in real time,imitating and simulating marine lives intuitively.Based on VV-Ocean,we establish a sea-land integration platform which can reproduce drifting and diffusion processes of oil spilling from sea bottom to surface.Environment factors such as ocean current and wind field have been considered in this simulation.On this platform oil spilling process can be abstracted as movements of abundant oil particles.The result shows that oil particles blend with water well and the platform meets the requirement for real-time and interactive rendering.VV-Ocean can be widely used in ocean applications such as demonstrating marine operations,facilitating maritime communications,developing ocean games,reducing marine hazards,forecasting the weather over oceans,serving marine tourism,and so on.Finally,further technological improvements of VV-Ocean are discussed. 相似文献
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在总结前人研究的基础上,综合岩石矿物、地球化学等分析测试资料对宜昌地区五峰组-龙马溪组黑色页岩层系中笔石的赋存状态及其沉积环境进行了深入研究。结果显示:五峰组-龙马溪组黑色页岩中笔石的赋存状态存在显著差异,笔石的丰度由下至上呈现由高到低的变化趋势,硅质炭质页岩中的笔石丰度最高,以杂乱堆积为主,部分可见弱定向排列特征;灰绿色泥岩与黑色硅质页岩中笔石丰度低,以碎片为主,且硅质页岩中的笔石碎片细小。笔石的分异度在纵向上也呈现出规律性变化,赫南特阶笔石分异度最低,埃隆阶与凯迪阶对应的笔石分异度高。综合研究表明,不同笔石赋存状态所对应的有机碳质量分数w(TOC)、围岩性质、氧化还原条件、古海洋环境与水动力条件均有所差异:高笔石丰度的页岩往往对应着较高的w(TOC);石英质量分数在40%~60%的黑色页岩中笔石最为发育;笔石在弱氧化和还原环境中均能保存,但还原环境更有利于笔石的大规模富集;纵向上笔石丰度与分异度变化均受到了古环境的显著影响, 赫南特冰期造成了笔石的大量死亡和分异度的显著降低;笔石的大量混杂堆积显示悬浮沉积是主要的沉积作用方式,而定向排列的笔石应是深水底流作用的结果。基于上述页岩中笔石赋存状态差异及其沉积地质指示,深入分析了不同笔石赋存状态的沉积环境并建立了五峰组-龙马溪组沉积期的笔石堆积模式。 相似文献
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RESPONSE OF THE OCEAN UPPER MIXED LAYER TO ATMOSPHERIC FORCING 总被引:1,自引:0,他引:1
刘秦玉 《中国海洋湖沼学报》1994,12(3):280-283
Using a one-dimension Turbulence Kinetic Energy(TKE)mixed layer model based on a simple eddyKinetic energy parameterization of the ocean upper mixed layer,some numerical examinations are intro- duced in this paper.These examination results show that the TKE ocean mixed layer model can respondwell to the effect of atmospheric forcing on the ocean upper mixed layer.The joint effect of wind stressand heat exchange on the ocean upper layer has nonlinear characteristics.The adjustment time of the re-sponse of the ocean upper mixed layer to the atmospheric forcing is about 12 hours in this model. 相似文献
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地下水资源是人类赖以生存和发展的重要保证,但我国地下水环境的形势不容乐观,对新建项目进行地下水环境影响预测并提出科学有效的地下水污染防治措施十分重要。该文以淄博开发区纸业公司搬迁改造项目为例,概化建立了水文地质概念模型,利用地下水非稳定流数值模拟对模拟范围内地下水时空分布规律进行研究。在此基础上,建立地下水溶质运移数值模型,选取COD、氨氮为污染因子,重点预测了非正常工况和事故工况下新建项目影响地下水环境的范围及程度。结果表明,非正常工况下该新建项目对地下水环境的影响程度更大,但采取严格保护措施后可防止污水泄漏进而污染地下水。 相似文献
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The wave-forcing ’Coriolis-Stokes forcing’ and ’Stokes-vortex force’ induced by Stokes drift affect the upper ocean jointly.To study the effect of the wave-induced Stokes drift on the dynamics of the ocean mixed layer,a new three-dimensional(3D) numerical model is derived using the primitive basic equations and Eulerian wave averaging.The Princeton Ocean Model(POM),a 3D primitive equation ocean model is used with the upper wave-averaged basic equations.The global ocean circulation is simulated using the POM model,and the Stokes drift is evaluated based on the wave data generated by WAVEWATCH III.We compared simulations with and without the Stokes drift.The results show that the magnitude of the Stokes drift is comparable with the Eulerian mean current.Including the Stokes drift in the ocean model affects both the Eulerian current and the Lagranian drift and causes the vertical mixing coefficients to increase. 相似文献
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Christopher N.K. Mooers Inkweon Bang 《中国海洋大学学报(英文版)》2005,4(4):288-292
The Florida Current (FC) largely fills the Straits of Florida and is variable on a broad spectrum of time and space scales. Some portions of the variability are due to variable forcing by tides, winds, heating/cooling, and throughflow; other portions are due to intrinsic instabilities of the FC. To predict, as well as to better understand this complex regime, a nowcast/forecast system (East Florida Shelf Information System (EFSIS)) has been implemented and assessed (http://efsis. rsmas. miami. edu). EFSIS is based on an implementation of the Princeton Ocean Model (POM) with mesoscale-admitting resolution on a curvilinear grid. It is forced by a mesoscale numerical weather prediction system (called Eta) run operationally by the National Centers for Environmental Prediction (NCEP), eight tidal constituents from a global tidal model, and lateral boundary conditions from an operational global ocean prediction model, i.e., the Navy Coastal Ocean Model (NCOM). Real-time observations of coastal sea level, coastal sea surface temperature, coastal HF radar-derived surface current maps, and FC volume transport are used to verify and validate EFSIS. EFSIS is part of an evolving strategy for real-time predictive coastal ocean modeling methodology, and for fostering the understanding of the variability of the regime on several time and space scales. Here, some of the verification and validation results are provided, as well as diagnostic analyses of dynamical processes. The central point is that an example is provided of a 'scientific revolution' in progress that combines real-time observations and numerical circulation models to yield a credible sequence of synoptic views of coastal ocean circulation for the first time. 相似文献
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The inflow angle of tropical cyclones(TC) is generally neglected in numerical studies of ocean surface waves induced by TC.In this study,the impacts of TC inflow angle on ocean surface waves were investigated using a high-resolution wave model.Six numerical experiments were conducted to examine,in detail,the effects of inflow angle on mean wave parameters and the spectrum of wave directions.A comparison of the waves simulated in these experiments shows that inflow angle significantly modifies TC-induced ocean surface waves.As the inflow angle increases,the asymmetric axis of the significant wave height(SWH) field shifts 30u clockwise,and the maximum SWH moves from the front-right to the rear-right quadrant.Inflow angle also affects other mean wave parameters,especially in the rear-left quadrant,such as the mean wave direction,the mean wavelength,and the peak direction.Inflow angle is a key factor in wave models for the reproduction of double-peak or multi-peak patterns in the spectrum of wave directions.Sensitivity experiments also show that the simulation with a 40u inflow angle is the closest to that of the NOAA statistical SLOSH inflow angle.This suggests that 40u can be used as the inflow angle in future TC-induced ocean surface wave simulations when SLOSH or observed inflow angles are not available. 相似文献
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岩溶含水层中的地下水是重要的可饮用水来源,由于其复杂的水文地质特征,采用数值模型分析和评价含水层中地下水环境极具挑战性。采用变饱和度流动方程描述含水层基质中的饱和-非饱和流动,采用管道流方程描述岩溶管道中的层流及紊流流动,基于流动解采用对流弥散方程分别描述基质与管道中的溶质迁移过程。根据相关实验数据以及MODFLOW-CFP程序的模拟结果对流动模拟的准确性进行验证,并基于此开展了岩溶管道以及非饱和参数对地下水流动及污染物迁移影响的模拟。结果显示,数值模型能很好地重现含水层中饱和区与非饱和区以及岩溶管道的地下水动态,岩溶管道对含水层的渗流场产生了较大的影响。管道中快速流动的特性使得周围的水向其中汇集,影响了局部流动场,进而使得泄露的污染物质随水流进入管道,快速向管道出口处(泉点)迁移,突破曲线显示管道出口处的污染物浓度响应速度远快于基质中对应的位置,非饱和参数对管道中污染物浓度的响应速率有着不同程度的影响。建立的模型完善了岩溶含水层中非饱和区地下水流动、污染物运移以及基质-管道流动与溶质运移耦合模拟等方面的工作,加深了对岩溶含水层地下水动力学以及污染物迁移过程的认识,对岩溶水文地质及地下... 相似文献
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KANG Ying PENG LinhuiDepartment of Physics Ocean University of China Qingdao P.R.China 《中国海洋大学学报(英文版)》2003,2(2):218-223
The variations of ocean environmental parameters invariably result in variations of local modal wave numbers of a sound pressure field. The asymptotic Hankel transform with a short sliding window is applied to the complex sound pressure field in the water containing a mesoscale eddy to examine the variation of local modal wave numbers in such a range-dependent environment. The numerical simulation results show that modal wave number spectra obtained by this method can reflect the location and strength of a mesoscale eddy, therefore it can be used to monitor the strength and spatial scale of ocean mesoscale eddies. 相似文献
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中国台湾地区海洋负荷潮汐对重力、位移、倾斜和应变固体潮观测的影响 总被引:3,自引:3,他引:0
利用最新的由卫星测高数据解算获得的Csr4.0全球海潮模型,中国近海海潮资料和标准地球模型负荷格林函数,采用积分格林函数方法研究了台湾地区10个台站的重力,位移,倾斜和应变固体潮观测中的海潮负荷效应。给出了4个主要潮波(O1,K1,M2,S2)的负荷振幅和相位,研究了负荷应变花分布特征,构制了台北站的负荷时变特征,数值结果说明,台湾地区各台站受海潮影响十分明显,因此在实施重力,位移,倾斜和应变固体潮观测中心必须考虑海潮负荷效应。 相似文献
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广州地区地下水咸化现象由来已久,通过透射电子显微镜对广州珠江三角洲地下水的咸化原因进行了研究,并评价了其咸化程度。通过研究广州地区地下水中的微粒特征,包括观察微粒的形貌、结晶程度和化学成分等特征,同时对比现代海水微粒特征,讨论了微粒特征用于地下水咸化原因探究和评价的可行性。研究发现,在咸化程度不同的样品中,微粒中Cl含量不同,没有咸化的样品中难以找到Cl元素,咸化程度越高,微粒中Cl含量可以越高。同时,在受到海水入侵的地下水微粒中发现了具有海洋来源含Sr、Ba等微量元素的微粒,这些微量元素在一定程度上可视为海水的示踪剂,说明该组地下水受到了不同程度的海水浸染。通过透射电子显微镜分析研究了地下水中的微粒,结果表明,该研究区地下水中的微粒继承了海水中的微粒特征,广州市地下水的咸化是由于海水入侵所致,因此,利用微粒特征用于海水入侵的判别分析和评价是可行的。类似地,该方法同样可用于水污染调查以及地下水找矿研究。 相似文献
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The effects of the mixing of wave transport flux residual(Bvl) on the upper ocean is studied through carrying out the control run(CR) and a series of sensitive runs(SR) with ROMS model.In this study,the important role of Bvl is revealed by comparing the ocean temperature,statistical analysis of errors and evaluating the mixed layer depth.It is shown that the overestimated SST is improved effectively when the wave-induced mixing is incorporated to the vertical mixing scheme.As can be seen from the vertical structure of temperature 28℃ isotherm changes from 20 min CR to 35 m in SR3,which is more close to the observation.Statistic analysis shows that the root-mean-square errors of the temperature in 10 m are reduced and the correlation between model results and observation data are increased after considering the effect of Bvl.The numerical results of the ocean temperature show improvement in summer and in tropical zones in winter,especially in the strong current regions in summer.In August the mixed layer depth(MLD) which is defined as the depth that the temperature has changed 0.5℃ from the reference depth of 10 m is further analyzed.The simulation results have a close relationship with undetermined coefficient of Bvl,sensitivity studies show that a coefficient about 0.1 is reasonable value in the model. 相似文献
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Zhongqiang Zheng Jianpeng Xu Peng Huang Lei Wang Xiaoguang Yang Zongyu Chang 《中国海洋大学学报(英文版)》2016,15(1):69-77
Submersible buoy systems are widely used for oceanographic research,ocean engineering and coastal defense.Severe sea environment has obvious effects on the dynamics of submersible buoy systems.Huge tension can occur and may cause the snap of cables,especially during the deployment period.This paper studies the deployment dynamics of submersible buoy systems with numerical and experimental methods.By applying the lumped mass approach,a three-dimensional multi-body model of submersible buoy system is developed considering the hydrodynamic force,tension force and impact force between components of submersible buoy system and seabed.Numerical integration method is used to solve the differential equations.The simulation output includes tension force,trajectory,profile and dropping location and impact force of submersible buoys.In addition,the deployment experiment of a simplified submersible buoy model was carried out.The profile and different nodes' velocities of the submersible buoy are obtained.By comparing the results of the two methods,it is found that the numerical model well simulates the actual process and conditions of the experiment.The simulation results agree well with the results of the experiment such as gravity anchor's location and velocities of different nodes of the submersible buoy.The study results will help to understand the conditions of submersible buoy's deployment,operation and recovery,and can be used to guide the design and optimization of the system. 相似文献
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针对传统海浪建模方法中存在海洋表面真实感差、计算复杂的问题,本文进行了基于光滑粒子流体动力学算法(SPH)与移动立方体算法(MC)相结合的海浪建模仿真研究。通过基于空间网格的粒子分配,建立了粒子群单向列表存储结构,在海浪粒子物理量计算时,实现了其光滑核半径内粒子群的快速检索,并基于拉格朗日流体控制方程,进行了海浪粒子受力分析及状态计算;在模拟海浪与环境障碍物碰撞时,将碰撞问题简化为粒子在一定时间段内所经过的路径与障碍物表面三角面片是否相交来进行判定,并假设粒子为理想刚体,采用改进的欧拉方法实现了粒子新位置的动态计算;为增强海浪流体模拟的真实感,在移动立方体节点密度动态计算基础上,依据确定的海浪表面密度阈值,耦合MC算法进行了海浪表面的动态提取,从而实现了海浪三维表面建模与动态演变仿真。通过模拟验证了该算法的时效性与可行性,可为海洋环境信息三维可视化提供一定的参考。 相似文献