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本文叙述利用风暴潮模式和斜压大气模式耦合进行温带风暴潮预报.应用边界层阻尼定律预报风暴潮模式所需的海面风应力.本文进行了渤海风暴潮的个例研究.预报结果清楚地显示了温带风暴潮的特性.一些个例研究指出,风暴潮模式和计算风应力方案是令人满意的,而风暴潮预报精度非常依赖于气象预报. 相似文献
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一个高分辨率的长江口台风风暴潮数值预报模式及其应用 总被引：13，自引：1，他引：13
利用河口海岸海洋模式(ECOM-Si)建立了一个适用于长江口区风暴潮的数值预报模式.该模式采用对岸线有较好拟合能力的自然正交水平坐标系统和能分辨较复杂海底地形的垂直σ坐标系统.模式考虑了长江口径流量对风暴潮的影响,部分地考虑了天文潮和风暴潮非线性相互作用对风暴增水的影响.风暴潮预报的大气强迫场用模型气压场和模型风场.利用所建立的模式对长江口区台风风暴潮进行了8个个例模拟,模拟增水与实测增水的峰值相比较,平均绝对误差不足10cm.利用本研究建立的模式,就气象因子对风暴潮位的敏感性进行了数值试验.试验结果表明,台风中心气压降低(升高)20hPa可导致约100cm的风暴潮位升高(或降低).台风最大风速半径误差对台风增水的变化影响也较显著.试验还表明,长江径流量增加1倍(减半),可以造成风暴潮的平均增加25cm(减小13cm).天文潮位相变化对风暴增水的影响数值试验表明,当台风暴潮与天文潮在不同位相相互作用,可使风暴潮位最大增加达70cm或减小90cm. 相似文献
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概述了天津的历史风暴潮及潮灾,对天津沿海风暴潮进行了成因分析,引用了大量有关风暴潮的实例资料,对天津沿海的潮汐特性、致灾因素和防潮减灾提出了具体的建议.有些论点、论据是首次提出的.可供防潮决策部门参考. 相似文献
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本文采用ECOMSED模式模拟了影响东中国海的3次台风过程，经与实测资料对比验证了模型的可靠性。在此基础上设计了敏感性试验以考察海平面上升对风暴潮造成的影响。结果表明，海平面上升对风暴潮的影响在空间分布上不是一致的，且因具体台风过程而异。整体而言，海平面上升对风暴潮造成的影响有限。海平面上升0．5m，大部分站位风暴增水极值基本不变，即使海平面上升5m大部分站位的风暴增水极值相对改变量都小于10％。 相似文献
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Statistical analysis of the extreme values of the Baltic Sea level has been performed for a series of observations for 15–125 years at 13 tide gauge stations. It is shown that the empirical relation between value of extreme sea level rises or ebbs (caused by storm events) and its return period in the Baltic Sea can be well approximated by the Gumbel probability distribution. The maximum values of extreme floods/ebbs of the 100-year recurrence were observed in the Gulf of Finland and the Gulf of Riga. The two longest data series, observed in Stockholm and Vyborg over 125 years, have shown a significant deviation from the Gumbel distribution for the rarest events. Statistical analysis of the hourly sea level data series reveals some asymmetry in the variability of the Baltic Sea level. The probability of rises proved higher than that of ebbs. As for the magnitude of the 100-year recurrence surge, it considerably exceeded the magnitude of ebbs almost everywhere. This asymmetry effect can be attributed to the influence of low atmospheric pressure during storms. A statistical study of extreme values has also been applied to sea level series for Narva over the period of 1994–2000, which were simulated by the ROMS numerical model. Comparisons of the “simulated” and “observed” extreme sea level distributions show that the model reproduces quite satisfactorily extreme floods of “moderate” magnitude; however, it underestimates sea level changes for the most powerful storm surges. 相似文献
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Characteristics of abnormal waves in North Sea storm sea states 总被引：1，自引：0，他引：1
A data set of storm wave records from the North Sea is analysed. Using current definitions of abnormal waves, eight of the largest wind waves are defined as abnormal waves. Twenty-four of the largest waves in time series, with a height larger than 10 m and with big vertical asymmetry are chosen for further analysis. Their individual characteristics are investigated and related to the global sea state characteristics. A comparison between measured data, second-order theory predictions and offshore basin data is made. The results for the chosen waves do not coincide with predictions of second-order theory. Considering that wind wave is second- and third-order non-linear, a new relationship between skewness and kurtosis is proposed for the sea states in which extremely asymmetric large waves have occurred. Another relationship between kurtosis and abnormality index of maximum waves is proposed too. 相似文献
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Hourly sea level records from three stations in eastern Canada (Québec-Lauzon, Harrington-Harbour and Halifax) are analyzed both in frequency domain from 1970 to 1979 and in time domain during 1973. At the three stations, the deterministic model explains 90 to 96% of the total variability of sea level. The semidiurnal and diurnal tides contribute largely to its variations. The residual series, less than 10% of the initial variations of sea level, contain irregular values including extreme values of seiches and storm surges. Such random variations are analyzed and modeled following the method described by Box and Jenkins (1976). The long period variations (2 to 30 days) can be attributed to meteorological forcing (atmospheric pressure and winds). The short period variations (some hours to one day) can be attributed to longitudinal seiches, semidiurnal and diurnal atmospheric tides, and inertial oscillations. The water discharge from the St. Lawrence River contributes 29% of the monthly residual sea level at Qué 相似文献
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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。 相似文献
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近年来风暴潮等海洋灾害的频发,对沿海大型工程的防御能力提出了更高的要求。本研究结合广西北海港石步岭港区项目海岸防御工程的设计标准及现状,进行风暴潮和海浪灾害的风险性评估,把推算得到的防御工程应达到的理论顶高程与实测高程进行对比,评估该工程项目抵御海洋灾害的能力。研究发现考虑海平面上升之后的极端高潮位评估结果跟设计值相当;无论是设计高潮位还是极端高潮位下的N向波高的理论值均高于设计值;码头及其他防护岸段的实测最低高程均低于考虑波浪爬高影响之后的理论顶高程,存在一定风险,建议项目业主单位立即采取措施以降低海洋灾害风险。 相似文献
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利用北极海冰密集度资料和NCEP＼NCAR再分析资料，运用统计方法讨论了冬季鄂霍次克海及其邻近海区海冰异常与同期北太平洋风暴轴的联系。结果发现，冬季鄂霍次克海西南部海区海冰面积异常与北太平洋海温异常共同作用对北太平洋风暴轴在西北一东南方向的伸缩及强度的年际变化有重要影响，而在海温异常的共同作用下，鄂霍次克海东北部及舍列霍夫海海区海冰面积异常则主要影响风暴轴的南北位移和强弱。 相似文献
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海堤溃堤的主要原因是海堤根部被淘空所造成的海堤基础不稳固.溃堤主要发生在风暴潮期间.水深测量是发现海堤被淘空的较为可靠的方法和手段.介绍了黄河三角洲海堤淘空的监测方法和工程防范措施. 相似文献