Simulation of Storm Surge and Wave Due to Typhoon Isewan(5915)

An integrally coupled wave-tide-surge model was developed and then applied to the simulation of the wave-typhoon surge for the typhoon Isewan(typhoon Vera(5915)), which is the strongest typhoon that has struck Japan and caused incalculable damage. An integrally coupled tide-surge-wave model using identical and homogeneous meshes in an unstructured grid system was used to correctly resolve the physics of wave-circulation interaction in both models. All model components were validated independently. The storm surge and wave properties such as the surge height, the significant wave height, wave period and direction were reproduced reasonably under the meteorological forcing, which was reprocessed to be close to the observations. The resulting modeling system can be used extensively for the prediction of the storm surge and waves and the usual barotropic forecast.     

Wave Hindcast for the Neighbouring Seas of Korea Based on Loosely Coupled Wave-Tide-Surge Model

A hindcast simulation of 75 typhoons and winter monsoons which affected the coastal areas of Korean Peninsula is performed by use of a third generation ocean wave prediction model, WAM-cycle 4 model, loosely coupled with a com-bined tide and surge model. Typhoon wind fields are derived from the planetary marine boundary layer model for effective neutral winds embedding the vortical storm wind from the parameterized Rankin vortex type model in the limited areas of the overall modeled region. The hindcasted results illustrate that significant wave heights (SWH) considering the wave-tide-surge coupled process are significantly different from the results via the decoupled case especially in the region of the estuaries of the Changjiang Estuary, The Hangzhou Bay, and the southwestern tip of Korean Peninsula. This extensive model simulation is the first attempt to investigate the strong wave-tide-surge interaction for the shallow depth area along the coasts of the Yellow Sea and the East China Sea Continental     

Simulation of Storm Surge and Wave Due to Typhoon Isewan (5915)

An integrally coupled wave-tide-surge model was developed and then applied to the simulation of the wave-typhoon surge for the typhoon Isewan (typhoon Vera (5915)), which is the strongest typhoon that has struck Japan and caused incalculable damage. An integrally coupled tide-surge-wave model using identical and homogeneous meshes in an unstructured grid system was used to correctly resolve the physics of wave-circulation interaction in both models. All model components were validated independently. The storm surge and wave properties such as the surge height, the significant wave height, wave period and direction were reproduced reasonably under the meteorological forcing, which was reprocessed to be close to the observations. The resulting modeling system can be used extensively for the prediction of the storm surge and waves and the usual barotropic forecast.     

波流耦合作用下渤海及北黄海风暴潮增水及海浪过程的数值模拟

本文基于三维波流耦合FVCOM-SWAVE数值模式,采用Jelesnianski参数化风场与再分析数据集ECMWF风场数据叠加而成的合成风场作为外力驱动力,模拟了1818号"温比亚"台风引起北黄海及渤海海域风暴潮增减水及波浪的生长与消减过程,进而分析该海域在"温比亚"台风作用下波浪对流速垂向分布的影响。研究结果表明:合成风场得到的风速最大值及出现时刻与实测数据符合较好,合成风场较为合理,能够为模拟波流耦合机制下海域水动力变化提供准确的风场条件;几个测站的风暴潮增水模拟结果与实测数据较为吻合,FVCOM-SWAVE耦合系统合理地再现了"温比亚"台风在黄渤海引发的风暴潮增水以及台风浪过程。此外,计算结果显示"温比亚"期间黄渤海海域最大有效波高分布于台风中心外围,且位于台风前进方向上,波浪最大有效波高值与台风强度有关;在台风过境期间,波流相互作用对近岸海域流速的垂向分布具有一定影响,考虑波流相互作用可有效提高台风风暴潮数值模拟精度。研究结果对台风灾害预报、防灾减灾及港口建筑选址具有一定的参考意义。     

福建沿海浪潮耦合漫堤风险评估:以台风天兔为例

漫堤是天文潮、风暴潮与海浪等物理要素作用于海堤后海水翻越海堤的物理过程。本文利用天文潮-风暴潮-台风浪耦合模式(ADCIRC+SWAN)、基于非结构三角形网格和高分辨率地理数据(海堤位置和高程、岸线和水深等)构建福建沿海精细化漫堤风险等级评估系统。该系统在近岸网格分辨率最高达50m,可精确刻画福建沿海复杂地形。利用模拟的水位与海浪参数,采用波浪爬高公式计算得到各海堤堤前波浪爬高。按照总水位与波浪爬高之和与海堤高程的对比,将漫堤风险分为五个等级。对2013年的超强台风天兔过程进行后报检验。结果显示,该系统计算的漫堤情况与灾后调查的漫堤实况基本一致,结果准确,说明本研究中采用的漫堤风险评估标准和方法是可行的。在此基础上,设计了4种不同的台风强度等级,对福建沿海206条海堤进行了漫堤风险等级评估,探究台风强度对漫堤风险的影响。结果表明:波浪爬高对漫堤风险的影响高于单纯的风暴潮增水;风暴潮增水随台风强度的增强增量较小,对于漫堤的风险影响较小;福建沿海波浪爬高普遍较高,随着台风强度的增强,波浪爬高会显著增加漫堤的风险等级,且应重视台风浪对海堤造成的冲击所导致的溃堤灾害。本研究可为沿海防灾减灾提供科学依据。     

渤海波浪和潮汐风暴潮相互作用对波浪影响的数值研究

基于依赖波浪成长状态波令的表面风应力，提出了一个波浪和风暴潮潮汐运动相互作用的联合数值模式，实现了第三代波浪模式和三维风暴潮潮汐模式联合作用的数值研究，并结合渤海典型天气个例的研究，给出了渤海波浪和风暴潮潮汐相互作用对波浪影响的机制和大小量级的定量估计。研究表明，对不同天气过程，波浪和风暴潮潮汐相互作用对波浪影响的性质和大小不同；对强寒潮过程，对波浪影响主要由风暴潮所支配波高调制可达1m，在黄河口区一般达0．5m；对弱天气过程，对波浪影响主要由潮所控制，波高调制约在0．2m，联合作用模式给出的结果与实测更吻合。     

“烟花”台风影响下长江口水域波浪分布特征研究

台风往往会带来强风、大浪、风暴潮。强潮大浪给长江口深水航道整治工程的维护带来挑战。构建了覆盖中国海的台风浪—风暴潮耦合数学模型,模拟了台风“烟花”作用下长江口北槽水域波浪的发展过程,分析了长江口北槽水域波浪分布特点和台风强度。研究表明：叠加风场和潮汐模式共同驱动的台风浪―风暴潮耦合模型,可以准确模拟台风期间长江口水域波浪的生成和发展过程;“烟花”台风期间,外海大浪以东方向浪为主,长江口北槽南挡沙堤沿线有效波高最大值介于1.61~5.22 m之间,自东向西逐渐衰减;台风过程中,长江口北槽水域有效波高在台风二次登录时刻达到最大,口门处有5. 0 m以上大浪;依据台风过程中长江口风速及外海波高、周期与参考规范值对比分析得出,“烟花”台风过程波浪强度约为50年一遇。     

Storm surge simulation using wind-wave-surge coupling model

Simulation of a storm surge caused by Typhoon 9918 in the Yatsushiro Sea, Kyushu, Japan was hindcasted by the synchronous coupled wind-wave-surge model composed of a Meso-scale meteorological model (MM5) for the wind and sea surface pressure, a spectral third-generation wind-wave model (Wavewatch III) for waves, and the coastal ocean model (Princeton Ocean Model). Inclusion of the whitecap wave breaking stresses (whitecap dissipation stress) in the coastal ocean model made it possible to reproduce the extreme surge height in the extremely shallow bay.     

浪潮耦合的舟山渔港台风暴潮数值模拟

建立能精确模拟舟山渔港台风暴潮过程的浪潮耦合模型,对渔港防灾减灾具有重要意义。基于Delft3D中的FLOW和WAVE模块,在二重嵌套网格下建立风暴潮和波浪的耦合模型。以9711号台风Winnie为背景,验证耦合模型的可靠性,结果显示,风速、天文潮潮位、风暴潮潮位和有效波高的计算值与实测值吻合良好。利用风暴潮模型与耦合模型分别计算了舟山海域的风暴潮,分析了波浪对风暴潮潮位的抬升影响,定海和镇海站最大波浪增水分别为23 cm和34 cm,耦合模型的模拟精度要高于风暴潮模型。通过模拟9711号台风期间舟山渔港的风暴潮过程,分析了风暴潮的时空分布特征,并给出了浪潮耦合作用对于风暴潮时空分布的影响。     

浪、潮、风暴潮联合作用下的底应力效应

运用建立的二维非线性浪,潮和风暴耦全模式分析了波流相互作用下的底应力及其对耦合波浪场和流场的影响。由渤海的两次强寒潮过程的数值实验表明,在波流相互作用下,底应力明显增大,增大的底应力对波浪场影响甚微,但将明显改变水位和流速的大小,这种影响在近岸浅水区更加显著。     

海岛核电厂址的设计基准洪水位研究

随着滨海核电厂址的开发利用日趋饱和,选取海岛作为核电厂址成为一种新思路。针对海岛厂址易受台风灾害影响的问题,本文通过对天文高潮位、海平面上升、可能最大风暴潮增水和最大台风浪四个增水因子的研究来确定厂址的设计基准洪水位。结果表明:该区域10%超越概率的天文高潮位为3.14 m,未来80 a海平面上升幅度为0.31 m。基于MIKE21数值模型,以可能最大热带气旋参数为基础构建了多种假想台风路径,发现:当台风移动方向为NW向,距离厂址中心左侧0.5R(R为台风最大风速半径)时,风暴潮增水达到最大,增水最大值为2.99 m;当台风移动方向为W向,且距离厂址左侧R处时,台风浪波高达到最大,厂址前沿H_1/100波高最大值达到了8.02 m;岛屿东侧遭受的风暴潮和波浪威胁较其他方向更为严重。各水位影响因子组合叠加后海岛核电厂址设计基准洪水位可达11.25 m。相对于其他滨海厂址,海岛厂址的风暴潮增水相对偏小,但受波浪的影响更为显著。     

雷州市沿海风暴潮淹没危险性评估*

文章基于近岸海洋数值模式ADCIRC (a parallel advanced circulation model for oceanic, coastal and estuarine waters)和近海波浪数值模式SWAN (simulating waves nearshore), 建立雷州市高分辨率的风暴潮-海浪耦合漫滩数值模型, 并反演了对雷州市影响较为严重的1415号台风“海鸥”的风暴潮过程。经过对比分析得出, 波浪对雷州市沿海海域的风暴潮产生重要影响。然后以8007号台风路径为基础, 构造了7个不同等级共35组台风风暴潮案例, 计算分析出不同等级台风强度下雷州市风暴潮淹没范围及水深。900hPa等级下, 雷州市淹没面积达到463.2km²。文章还构造了60组可能最大风暴潮事件集, 计算得到雷州市可能最大台风风暴潮淹没范围及水深分布。在可能最大台风影响下, 大量海水将漫过海堤, 造成极其严重的淹没灾害, 雷州市总的淹没面积可达602.0km², 其中465.8km²的淹没面积达到了危险性等级 Ⅰ 级, 淹没水深大于3m。雷州市东岸的淹没灾害大于西岸。     

非结构网格模型在闽东沿海台风浪模拟中的应用

基于加密的非结构三角网格，以Holland模型风场叠加美国国家环境预报中心（NCEP）海面风场构造的合成风场驱动第三代浅水波浪数值模型（SWAN）对2017年影响闽东海域的“纳沙”和“泰利”台风过程进行数值模拟，并运用浮标站的实测数据对模拟结果进行验证.结果表明，模型计算的风速、有效波高与实测值符合较好，合成风场能较好地模拟台风期间的风速变化过程，SWAN模式能够合理地再现闽东沿海台风浪的时空分布特征.由模拟结果可见：台风“纳沙”中心越过台湾岛进入台湾海峡北部海面，受海峡地形的约束，其波浪场呈NE—SW向椭圆状分布，北部海域的浪高大于南部，闽东沿海遍布大范围的巨浪到狂浪；超强台风“泰利”未登陆闽东，当其台风中心与大陆的距离最近时，海面波浪场分布与台风风场结构一致，台风中心附近海域为14 m以上的怒涛区，巨浪遍布于闽东沿海.研究结果可为闽东沿海台风浪灾害预警和应急管理提供技术支撑和参考依据.     

A synchronously coupled tide–wave–surge model of the Yellow Sea

A coupled wave–tide–surge model has been established in this study in order to investigate the effect of tides, storm surges, and wind waves interactions during a winter monsoon on November 1983 in the Yellow Sea. The coupled model is based on the synchronous dynamic coupling of a third-generation wave model, WAM-Cycle 4, and the two-dimensional tide–surge model. The surface stress generated by interactions between wind and waves is calculated using the WAM-Cycle 4 directly based on an analytical approximation of the results obtained from the quasi-linear theory of wave generation. The changes of bottom friction factor generated by waves and current interactions are calculated by using simplified bottom boundary layer model. The model simulations showed that bottom velocity and effective bottom drag coefficient induced by combination of wave and current were increased in shallow waters of up to 50 m in the Yellow Sea during the wintertime strong storm conditions.     

Modeling of coupled tide–wave–surge process in the Yellow Sea

A coupled wave–tide–surge model has been developed in this study in order to investigate the effect of the interactions among tides, storm surges, and wind waves. The coupled model is based on the synchronous dynamic coupling of a third-generation wave model, WAM cycle 4, and the two-dimensional tide–surge model. The surface stress, which is generated by interactions between wind and wave, is calculated by using the WAM model directly based on an analytical approximation of the results using the quasi-linear theory of wave generation. The changes in bottom friction are created by the interactions between waves and currents and calculated by using simplified bottom boundary layer model. In consequence, the combined wave–current-induced bottom velocity and effective bottom drag coefficient were increased in the shallow waters during the strong storm conditions.     

舟山海域风暴潮特征及数值模拟研究

选择20个对舟山海域有较大影响的历史台风案例,开展定海站实测潮位数据的分析与归纳,总结得出20个台风中风暴潮过程增水最大值为5612号台风的207.1 cm,风暴潮高潮位最大值为9711号台风的283.7 cm。同时,在三维斜压水动力模型SELFE的基础上加入台风气压场和风场模块,建立了一个采用非结构三角形网格的天文潮-风暴潮耦合模型,模拟表明定海站的斜压效应较为明显,非线性耦合作用相对较弱,但两潮耦合风暴潮增水结果仍优于风暴潮单因子增水结果,与实际增水更为接近。在此基础上,以一定间隔在5612号台风原路径南北两侧各设计了2条平行路径,分别模拟两潮耦合风暴潮增水,结果表明5612号台风参数沿其原路径偏南1个最大风速半径距离的S1路径运动时可模拟得到定海站可能最大风暴潮增水为243.9 cm。最后,在S1路径下模拟可能最大风暴潮增水分别遭遇天文高、中、低潮位时的风暴潮高潮位,结果表明天文潮高潮时可得到可能最大风暴潮高潮位约为400 cm,天文中潮时次之,而天文低潮时风暴潮高潮位最低。     

A numerical study on the impact of tidal waves on the storm surge in the north of Liaodong Bay

A storm surge is an abnormal sharp rise or fall in the seawater level produced by the strong wind and low pressure field of an approaching storm system.A storm tide is a water level rise or fall caused by the combined effect of the storm surge and an astronomical tide.The storm surge depends on many factors,such as the tracks of typhoon movement,the intensity of typhoon,the topography of sea area,the amplitude of tidal wave,the period during which the storm surge couples with the tidal wave.When coupling with different parts of a tidal wave,the storm surges caused by a typhoon vary widely.The variation of the storm surges is studied.An once-in-a-century storm surge was caused by Typhoon 7203 at Huludao Port in the north of the Liaodong Bay from July 26th to 27th,1972.The maximum storm surge is about 1.90 m.The wind field and pressure field used in numerical simulations in the research were derived from the historical data of the Typhoon 7203 from July 23rd to 28th,1972.DHI Mike21 is used as the software tools.The whole Bohai Sea is defined as the computational domain.The numerical simulation models are forced with sea levels at water boundaries,that is the tide along the Bohai Straits from July 18th to 29th（2012）.The tide wave and the storm tides caused by the wind field and pressure field mentioned above are calculated in the numerical simulations.The coupling processes of storm surges and tidal waves are simulated in the following way.The first simulation start date and time are 00：00 July 18th,2012; the second simulation start date and time are 03：00 July 18th,2012.There is a three-hour lag between the start date and time of the simulation and that of the former one,the last simulation start date and time are 00：00 July 25th,2012.All the simulations have a same duration of 5 days,which is same as the time length of typhoon data.With the first day and the second day simulation output,which is affected by the initial field,being ignored,only the 3rd to 5th day simulation results are used to study the rules of the storm surges in the north of the Liaodong Bay.In total,57 cases are calculated and analyzed,including the coupling effects between the storm surge and a tidal wave during different tidal durations and on different tidal levels.Based on the results of the 57 numerical examples,the following conclusions are obtained：For the same location,the maximum storm surges are determined by the primary vibration（the storm tide keeps rising quickly） duration and tidal duration.If the primary vibration duration is a part of the flood tidal duration,the maximum storm surge is lower（1.01,1.05 and 1.37 m at the Huludao Port,the Daling Estuary and the Liaohe Estuary respectively）.If the primary vibration duration is a part of the ebb tidal duration,the maximum storm surge is higher（1.92,2.05 and 2.80 m at the Huludao Port,the Daling Estuary and the Liaohe Estuary respectively）.In the mean time,the sea level restrains the growth of storm surges.The hour of the highest storm tide has a margin of error of plus or minus 80 min,comparing the high water hour of the astronomical tide,in the north of the Liaodong Bay.     

1979-2018年间山东半岛沿海台风浪危险性分布的数值模拟研究

台风浪灾害在山东半岛沿海时常发生，对人类生命财产和基础设施构成很大威胁，因此，对山东半岛海域台风浪的危险性分析具有重要的现实意义。本研究使用ADCIRC+SWAN耦合数值模式采用Holland模型风场与NCEP再分析风场组合的风场驱动，对1979—2018年36次台风过境期间的海浪过程进行了模拟。以台风过境时最大有效波高及历时频数作为危险性评价指标，给出了山东半岛近岸台风浪强度等级分布、历时频数分布以及危险性指数分布。研究结果显示，山东半岛北部为台风浪低危险区，台风浪强度等级低且历时短；南部二级强度（有效波高范围为1.3—2.5m）以上台风浪发生较为频繁，危险性高于北部；东部台风浪强度可以达到四级（有效波高4m以上），危险性最高。     

2004年9月15日天津沿海潮位二次超过警戒水位的成因分析

2004年9月15日天津沿海高潮位两次超过4.70m的警戒水位,形成风暴潮灾害。着重分析了在第一次高潮位超过警戒水位后,特别是天津沿海已处于离岸风的作用下,高潮位再度超过警戒水位的原因,并对类似这种一次风暴潮过程而高潮位多次超过警戒水位的情况,针对不同的天气背景,进行历史资料的统计分析。结果表明:用超浅海开尔文波的传播理论能解释这种现象并得到了实况的验证。而且统计分析表明,台风和气旋造成的风暴潮灾害中高潮位多次超过警戒水位的现象所占的比例较高。     

台湾附近海域超强台风南玛都期间风暴潮对海浪影响的数值研究

采用海浪模式(Simulating Waves Nearshore,SWAN)与风暴潮模式(Advanced Circulation Model,ADCIRC)的耦合模式,模拟研究了2011年第11号超强台风南玛都期间,风暴潮对海浪的影响。通过对比耦合模式和非耦合模式模拟结果,发现对于该超强台风过程,台风中心附近的大浪区内风暴潮对海浪有显著影响:在台风中心沿前进方向的右前方,风暴潮使海浪波高减小;在台风中心和台风中心的左后方,风暴潮使海浪波高增大。台风进入台湾海峡之前,风暴潮对海浪波高的最大影响为10%左右;进入台湾海峡后,受地形和潮汐潮流的影响,海浪波高受到的最大影响增大到25%左右。上述结果对台风期间的海浪模拟有一定参考价值。