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1.
《中国海洋工程》2016,(1)
At 13:46 on March 11, 2011(Beijing time), an earthquake of Mw=9.0 occurred in Japan. By comparing the tsunami data from Guanhekou marine station with other tsunami wave observation gathered from southeast coastal area of China, it was evident that, only in Guanhekou, the position of the maximum wave height appeared in the middle part rather than in the front of the tsunami wave train. A numerical model of tsunami propagation based on 2-D nonlinear shallow water equations was built to study the impact range and main causes of the special tsunami waveform discovered in Jiangsu coastal area. The results showed that nearly three-quarters of the Jiangsu coastal area, mainly comprised the part north of the radial sand ridges, reached its maximum tsunami wave height in the middle part of the wave train. The main cause of the special waveform was the special underwater topography condition of the Yellow Sea and the East China Sea area, which influenced the tsunami propagation and waveform significantly. Although land boundary reflection brought an effect on the position of the maximum wave height to a certain extent, as the limits of the incident waveform and distances between the observation points and shore, it was not the dominant influence factor of the special waveform. Coriolis force's impact on the tsunami waves was so weak that it was not the main cause for the special phenomenon in Jiangsu coastal area. The study reminds us that the most destructive wave might not appear in the first one in tsunami wave train. 相似文献
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This paper presents a local tsunami simulation, including the initial displacement field model of tsunami source and tsunami wave propagation model. We deduced the tsunami wave equation; applied the ma... 相似文献
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A numerical study which takes into account wave dispersion effects has been carried out in the Indian Ocean to reproduce the initial stage of wave propagation of the tsunami event that occurred on December 26, 2004. Three different numerical models have been used: the nonlinear shallow water (nondispersive), the nonlinear Boussinesq, and the full Navier-Stokes aided by the volume of fluid method to track the free surface. Numerical model results are compared against each other. General features of the wave propagation agreed very well in all numerical studies. However some important differences are observed in the wave patterns, i.e., the development in time of the wave front is shown to be strongly connected to the dispersion effects. Discussions and conclusions are made about the spatial and temporal distribution of the free surface reaffirming that the dispersion mechanism is important for tsunami hazard mitigation. 相似文献
5.
A numerical study which takes into account wave dispersion effects has been carried out in the Indian Ocean to reproduce the initial stage of wave propagation of the tsunami event that occurred on December 26, 2004. Three different numerical models have been used: the nonlinear shallow water (nondispersive), the nonlinear Boussinesq, and the full Navier-Stokes aided by the volume of fluid method to track the free surface. Numerical model results are compared against each other. General features of the wave propagation agreed very well in all numerical studies. However some important differences are observed in the wave patterns, i.e., the development in time of the wave front is shown to be strongly connected to the dispersion effects. Discussions and conclusions are made about the spatial and temporal distribution of the free surface reaffirming that the dispersion mechanism is important for tsunami hazard mitigation. 相似文献
6.
2015年9月16日22时54分（当地时间）智利中部近岸发生Mw8.3级地震,震源深度25 km。同时,强震的破裂区长200 km,宽100 km,随之产生了中等强度的越洋海啸。海啸影响了智利沿岸近700 km的区域,局部地区监测到近5 m的海啸波幅和超过13 m的海啸爬坡高度。太平洋区域的40多个海啸浮标及200多个近岸潮位观测站详细记录了此次海啸的越洋传播过程,为详细研究此次海啸近场及远场传播及演化规律提供了珍贵的数据。本文选择有限断层模型和自适应网格海啸数值模型建立了既可以兼顾越洋海啸的计算效率又可以实现近场海啸精细化模拟的高分辨率海啸模型。模拟对比分析了海啸的越洋传播特征,结果表明采用所建立的模型可以较好地再现远场及近场海啸特征,特别是对近场海啸的模拟结果非常理想。表明有限断层可以较好地约束近场、特别是局部区域的破裂特征,可为海啸预警提供更加精确的震源信息,结合高分辨率的海啸数值预报模式实现海啸传播特征的精细化预报。本文结合观测数据与数值模拟结果初步分析了海啸波的频散特征及其对模型结果的影响。同时对观测中典型的海啸波特征进行的简要的总结。谱分析结果表明海啸波的能量主要分布在10~50 min周期域内。这些波特征提取是现行海啸预警信息中未涉及,但又十分重要的预警参数。进一步对这些波动特征的详细研究将为海啸预警信息及预警产品的完善提供技术支撑。 相似文献
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植被斜坡岸滩海啸波消减数值模拟研究 总被引：1，自引：0，他引：1
An explicit one-dimensional model based on the shallow water equations(SWEs) was established in this work to simulate tsunami wave propagation on a vegetated beach. This model adopted the finite-volume method(FVM)for maintaining the mass balance of these equations. The resistance force caused by vegetation was taken into account as a source term in the momentum equation. The Harten–Lax–van Leer(HLL) approximate Riemann solver was applied to evaluate the interface fluxes for tracing the wet/dry transition boundary. This proposed model was used to simulate solitary wave run-up and long-periodic wave propagation on a sloping beach. The calibration process suitably compared the calculated results with the measured data. The tsunami waves were also simulated to discuss the water depth, tsunami force, as well as the current speed in absence of and in presence of forest domain. The results indicated that forest growth at the beach reduced wave energy loss caused by tsunamis. A series of sensitivity analyses were conducted with respect to variable parameters(such as vegetation densities, wave heights, wave periods, bed resistance, and beach slopes) to identify important influences on mitigating tsunami damage on coastal forest beach. 相似文献
8.
Forecasting of tsunami wave heights at the Russian coast of the Black Sea is discussed. Prognostic numerical calculations
of tsunamis were carried out for the tsunami sources uniformly distributed in the Black Sea basin (a total of 55 events).
Their results are compared with the results of numerical modeling of the historical events (in 1939 and 1966) and the data
of not numerous measurements. A preliminary forecast is made on this basis for the tsunami wave heights along the Russian
coast of the Black Sea. 相似文献
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2016年全球地震海啸监测预警与数值模拟研究 总被引：2，自引：0，他引：2
回顾了国家海洋环境预报中心(国家海洋局海啸预警中心)2016年全球地震海啸监测预警的总体状况, 并基于震源生成模型和海啸传播数值模型的计算结果详细介绍了几次主要海啸事件及其影响特性。2016年全年国家海洋环境预报中心总共对全球6.5级(中国近海5.5级)以上海底地震响应了45次,发布海啸信息81期, 没有发生对我国有明显影响的海啸。结合精细化的数值模拟结果和浮标监测数据,重点介绍了苏门达腊7.8级地震海啸、厄瓜多尔7.8级地震海啸、新西兰7.1级和7.8级地震海啸, 以及所罗门7.8级地震海啸的波动特征和传播规律, 模拟结果与实测海啸波符合较好。针对厄瓜多尔7.8级地震海啸事件, 本文比较分析了均匀断层模型和多源有限断层模型对模拟结果的影响; 针对新西兰7.1级地震海啸, 探讨了色散效应对海啸波在大水深、远距离传播过程的影响规律。 相似文献
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越洋海啸的数值模拟及其对我国的影响分析 总被引：7，自引：2，他引：5
简要介绍了地震海啸产生的物理机制、海啸波在大洋中的传播特性以及海啸所具有的超强破坏力可能引发的巨大灾害;概述了全球地震海啸发生的频率和太平洋区域历史海啸的时空分布;整理分析了我国沿海发生海啸的频次和空间分布。针对越洋海啸传播的特点,采用基于波浪追逐原理和自适应网格加密技术的海啸数值模型对1960智利海啸进行了数值模拟,将模拟的结果与历史记录进行了对比,验证了模型的可靠性。通过对数值模拟结果的分析,初步讨论了我国沿海地区越洋海啸的危险性,并定量阐述了越洋海啸对我国各海区的影响。 相似文献
11.
I. S. Kostenko A. A. Kurkin E. N. Pelinovsky A. Yalciner 《Izvestiya Atmospheric and Oceanic Physics》2016,52(1):89-100
The features of the propagation of the tsunami of March 11, 2011 in the northeastern Pacific have been studied with the aim of revealing the degree of influence of the Kuril Islands on the penetration of the tsunami in the Sea of Okhotsk. For this, a series of computational experiments have been performed within the shallow water theory using bathymetry (1) with and (2) without the Kuril Islands. The wave heights calculated have been analyzed, and the tsunami’s magnitude and intensity in the Sea of Okhotsk have been estimated. The computational experiments performed allow assessment of a decrease in the tsunami intensity while passing the Kuril Islands. 相似文献
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海啸波对近岸岛礁影响的数值模拟研究 总被引：1，自引：0，他引：1
基于Okada有限断层模型和非线性浅水波方程,结合高精度嵌套网格建立了越洋（中国近海）-局部-近岸岛礁的海啸生成与传播的数值模型。以三亚凤凰岛为例,首先针对2011日本地震海啸,模拟分析了海啸波沿中国沿海大陆架的传播特征及对凤凰岛的影响规律。在取得验证结果的基础上,进一步讨论了中国近海的马尼拉海沟和琉球海沟的潜在海啸源,以及环太平洋的21个潜在特大越洋海啸对凤凰岛的影响特征。依据海啸波在抵达凤凰岛的波浪特征,结合傅里叶频谱分析方法,探索了近岸岛礁对海啸波的放大效应。结果表明,中国近海一般震级的海啸和特大越洋海啸对凤凰岛存在一定影响,最大波幅接近1 m,传播时间从3 h到27 h不等。受三亚东南半岛的影响,琉球海沟激发的海啸和越洋海啸在凤凰岛的放大效应相对于马尼拉海沟较小,其频率集中在0.8×10-4~2×10-4 Hz。马尼拉海沟产生的海啸波在凤凰岛产生了较为显著的放大效应,对于凤凰岛是值得关注的高风险海啸源。 相似文献
13.
E. A. Kulikov I. V. Fine O. I. Yakovenko 《Izvestiya Atmospheric and Oceanic Physics》2014,50(5):498-507
The March 11, 2011, megaquake caused a catastrophic tsunami recorded throughout the Pacific. This paper presents an analysis of the sea-level records obtained from deep-water tsunami meters (DART and NEPTUNE). To evaluate the effect of the sea-level oscillations’ decay, a statistical analysis of observations and numerical modeling of tsunami generation and propagation have been conducted. The main goal is to uncover physical mechanisms of the tsunami wave field formation and evolution at scales up to tens of thousands of kilometers in space and a few days in time. It is shown that the tsunami lifetime is related to the wave-energy diffusion and dissipation processes. The decay time of the variance of the tsunami-generated level oscillations is about 1 day. Multiple reflections and scattering by irregularities of the bottom topography make the field of the secondary tsunami waves stochastic and incoherent: the distribution of the wave energy in the ocean reaches a statistical equilibrium in accordance with the Rayleigh-Jeans law of equipartition of the wave energy per degree of freedom. After the tsunami front has passed, the secondary-wave energy density turns out to be inversely proportional to the water depth. 相似文献
14.
This paper presents optical measurements of tsunami inundation through an urban waterfront in a laboratory wave basin. The physical model was constructed at 1:50 scale and was an idealization of the town of Seaside, Oregon. The fixed-bed model was designed to study the initial inundation zone along an urban waterfront, such that the flow around several large buildings could be observed. This paper presents an analysis of the optical measurements made with two overhead video cameras, focusing on tracking the leading edge of the tsunami inundation through the urban waterfront and quantifies the accuracy of the algorithm used to track the edge. The results show that the methodology provides high-resolution information in both time and space of the leading edge position, and that these data can be used to quantify the influence of large macro-roughness features on the tsunami inundation processes in laboratory settings. The overall effect of the macro-roughness was to decrease the bore propagation speed relative to the control section with no macro-roughness. The bore speed could be reduced by as much as 40% due to the presence of the macro-roughness relative to the control section. 相似文献
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应用内外解匹配的方法和驻相法推导了柱坐标系下地震引起的水面波动方程的解,即推导了地震海啸波生成与传播的理论方程,并对越洋地震海啸理论方程进行了求解。基于Boussinesq方程出发,建立了二维越洋海啸波传播数学模型,并对越洋海啸进行了数值计算,计算方法采用有限差分方法,差分格式采用交替方向隐格式(Alternating Direction Implicit即ADI方法)。利用越洋海啸计算模式对发生在大洋中的地震海啸进行了模拟,将数值模拟结果与地震海啸波理论方程的计算结果进行了比较,两种计算结果吻合较好。 相似文献
17.
In this paper the aim is to investigate whether there are differences between the dispersion and non-dispersion solutions on tsunami propagation. For this purpose, two numerical models of tsunami propagation are compared. One of these numerical models is a nondispersive model that uses Saint Venant equations and the other is a dispersive model that uses Boussinesq equations. The tsunamis resulting from a submarine mass failure (SMF) which is settled at the bottom of the north eastern Sea of Marmara are examined. An analytical solution considering wave dispersion is developed for obtaining near-field tsunami amplitudes above the submarine mass failure. Numerical modeling is used at the sea surface from the common boundary called as liquid boundary with incident waves up to the coastal regions to get the tsunami amplitudes. The output of the analytical model is taken as the disturbances for the numerical method. In the numerical solutions TELEMAC-2D software system is used for both dispersive and nondispersive modeling. The results of the dispersive and nondispersive models are compared to each other. Both temporal and spatial differences in the amplitudes and wave shapes are examined. The obtained results demonstrate that there are no noticeable differences between the dispersion and non-dispersion solutions except some special cases and some special landslide velocities. 相似文献
18.
The linear model of long waves is used for the evaluation of the parameters of tsunami waves along the South Coast of Crimea,
in the near-Kerch zone, and near the northeast coast of the Black Sea. Our numerical investigations are carried out for 24
probable locations of the elliptic zones of tsunami generation over the continental slope of the basin. The amplitude characteristics
of tsunamis are computed for 27 sites of the Black-Sea coast. It is shown that significant strengthening of tsunami waves
is possible in the course of their propagation toward the coast. The highest waves are formed at the sites of the coast closest
to the seismic source. The dependence of the intensity of tsunami waves along the Black-Sea coast on the location of the seismic
source and its magnitude is analyzed. 相似文献
19.
A. B. Rabinovich 《Izvestiya Atmospheric and Oceanic Physics》2014,50(5):445-458
Deep-sea tsunami measurements play a major role in understanding the physics of tsunami wave generation and propagation, and in the creation of an effective tsunami warning system. The paper provides an overview of the history of tsunami recording in the open ocean from the beginning (about 50 years ago) to the present day. It describes modern tsunami monitoring systems, including the Deep-ocean Assessment and Reporting of Tsunamis (DART), innovative Japanese bottom cable projects, and the NEPTUNE-Canada geophysical bottom observatory. The specific peculiarities of seafloor longwave observations in the deep ocean are discussed and compared with those recorded in coastal regions. Tsunami detection in bottom presure observations is exemplified based on analysis of distant (22000 km) records of the 2004 Sumatra tsunami in the northeastern Pacific. 相似文献
20.
Revisiting the February 6th 1783 Scilla (Calabria, Italy) landslide and tsunami by numerical simulation 总被引：1，自引：0，他引：1
On February 6th, 1783, a landslide of about 5 × 106 m3 triggered by a 5.8 M earthquake occurred near the village of Scilla (Southern Calabria, Italy). The rock mass fell into the sea as a rock avalanche, producing a tsunami with a run-up as high as 16 m. The tsunami killed about 1,500 people, making it one of the most catastrophic tsunamis in Italian history. A combined landslide-tsunami simulation is proposed in this paper. It is based on an already performed reconstruction of the landslide, derived from subaerial and submarine investigation by means of geomorphological, geological and geomechanical surveys. The DAN3D model is used to simulate the landslide propagation both in the subaerial and in the submerged parts of the slope, while a simple linear shallow water model is applied for both tsunami generation and propagation. A satisfying back-analysis of the landslide propagation has been achieved in terms of run-out, areal distribution and thickness of the final deposit. Moreover, landslide velocities comparable to similar events reported in the literature are achieved. Output data from numerical simulation of the landslide are used as input parameters for tsunami modelling. It is worth noting that locations affected by recordable waves according to the simulation correspond to those ones recorded by historical documents. With regard to run-up heights a good agreement is achieved at some locations (Messina, Catona, Punta del Faro) between computed and real values, while in other places modelled heights are overestimated. The discrepancies, which were most significant at locations characterized by a very low slope gradient in the vicinity of the landslide, were probably caused by effects such as wave breaking, for which the adopted tsunami model does not account, as well as by uncertainties in the historical data. 相似文献