Risk assessment of coastal flooding disaster by storm surge based on Elevation-Area method and hydrodynamic models:Taking Bohai Bay as an example

The future inundation by storm surge on coastal areas are currently ill-defined.With increasing global sealevel due to climate change,the coastal flooding by storm surge is more and more frequently,especially in coastal lowland with land subsidence.Therefore,the risk assessment of such inundation for these areas is of great significance for the sustainable socio-economic development.In this paper,the authors use Elevation-Area method and Regional Ocean Model System(ROMS)model to assess the risk of the inundation of Bohai Bay by storm surge.The simulation results of Elevation-Area method show that either a 50-year or 100-year storm surge can inundate coastal areas exceeding 8000 km^(2);the numerical simulation results based on hydrodynamics,considering ground friction and duration of the storm surge high water,show that a 50-year or 100-year storm surge can only inundate an area of over 2000 km^(2),which is far less than 8000 km^(2);while,when taking into account the land subsidence and sea level rise,the very inundation range will rapidly increase by 2050 and 2100.The storm surge will greatly impact the coastal area within about 10-30 km of the Bohai Bay,in where almost all major coastal projects are located.The prompt response to flood disaster due to storm surge is urgently needed,for which five suggestions have been proposed based on the geological background of Bohai Bay.This study may offer insight into the development of the response and adaptive plans for flooding disasters caused by storm surge.

3D Simulation of Storm Surge Disaster Based on Scenario Analysis

The occurrence of storm surge disaster is often accompanied with floodplain, overflow, dike breach and other complex phenomena, while current studies on storm surge flooding are more concentrated on the 1D/2D numerical simulation of single disaster scenario(floodplain, overflow or dike breach), ignoring the composite effects of various phenomena. Therefore, considering the uncertainty in the disaster process of storm surge, scenario analysis was firstly proposed to identify the composite disaster scenario including multiple phenomena by analyzing key driving forces, building scenario matrix and deducing situation logic. Secondly, by combining the advantages of k-ω and k-ε models in the wall treatment, a shear stress transmission k-ω model coupled with VOF was proposed to simulate the 3D flood routing for storm surge disaster. Thirdly, risk degree was introduced to make the risk analysis of storm surge disaster. Finally, based on the scenario analysis, four scenarios with different storm surge intensity(100-year and 200-year frequency) were identified in Tianjin Binhai New Area. Then, 3D numerical simulation and risk map were made for the case.

Research on the Emergency Response Mechanism and the Applications on Coastal Communities Storm Disaster Management

In this paper, we conduct research on the emergency response mechanism and applications on the coastal communities storm disaster management. Investment of pre-disaster prevention and the post-disaster remedy is larger in emergency in the financial system that has been structural problems, although in a disaster and financial support is especially important after a disaster, but increase before preventive investment should be the focus of our general government. Before preventive emergency government investment is to prevent incident broke out and reduce the incident after the outbreak of the impact of the main means. Under these circumstances, we analyze the coastal communities storm disaster management mode with the integration of the enhanced emergency response mechanism that will be meaningful for promoting the management efficiency and effectiveness.

A study of cooperation processes in multi-agent systems of storm surge disaster

Collaborative governance mechanism is a public management process that emphasizes the establishment of trust relationship between various subjects within the government and between multiple subjects such as the government and non-government based on the needs of the interest community,so as to achieve the advantages of collaborative governance.It is an important measure to improve the national storm surge disaster management system and realize the modernization of disaster management capacity.It is also the trend of the government to improve public management.Based on the results of relevant national bulletins,the storm surge disaster is selected which is the most characteristic of Marine disasters in the scope of marine public management.We select Zhejiang Province as the research area,which is heavily affected by storm surge disaster.Based on the case subjects of previous major storm surge disasters in Zhejiang Province,we analyze the specific measures taken by relevant subjects to deal with storm surge disasters.This paper presents the current situation of the participants and the cooperation problems among the participants,finds out the causes of the problems,studies and puts forward countermeasures and suggestions for the coordination management among the participants,provides certain ideas for further developing the disaster prevention and reduction and emergency management of storm surge disasters in coastal areas in order to improve the understanding of multiple subjects on the emergency management of storm surge disasters.

THE TYPHOON DISASTERS AND RELATED EFFECTS IN CHINA

China is one of the countries which were affected very seriously by tropical cyclones. In this paper, the active features of tropical cyclones which affected and landfell over China, the distinguishing characteristics of typhoon disasters and related formation laws have been studied, and the impact of trphoon disasters on China's socio-economic development have been discussed. The study reveals that typhoon disasters which affected China are characterized by high freqency in occurrence, violent in sudden occurrence, remarkable effects in China,widescope in impact and severe intensities in disasters, and this type of disaster was caused by huge gales, rainstorms, storm surges and reatal chain-disasters.Typhoon disasters have not only caused great casualties but also exerted severe effects on every economic departments in China. There is an annual increasing tendency in direct economic loss caused by taphoon disasters and since 1990, the annual average economic loss has totalled up to over lo billion RMB yuan.

Studies on marine dynamic disasters

Marine dynamic disasters,including storm surges,huge waves,and sea ice,are the most harmful natural disasters aff ecting coastal countries in the world.Under the infl uence of global climate change,the mechanisms,frequencies,and damage severity of marine dynamic disasters are exhibiting new characteristics.The enormity,unpredictability,and chain eff ects of these disasters have become increasingly prominent,and the losses endured by coastal countries around the world have been increasing year by year.Therefore,the prediction of,risk assessment for,and emergency response to marine dynamic disasters are important issues for disaster prevention and mitigation worldwide.

Nourishment and disaster mitigation efficiency of feeding sand on the dry section of a dissipative beach

To explore the nourishment effect and disaster reduction efficiency of a fully dissipative dry beach under the impact of storms,this paper uses the measured topography and hydrodynamic data to establish a one-dimensional numerical model of the XBeach beach profile.By numerically modeling the change in the nourished profile for different dry beach widths under normal waves and storm conditions and the recovery process of the profile after the storm,the degree of response in dry beach nourishment for the fully dissipative beach is analyzed.The results show that under normal wave conditions,the response of the nourished dry beach is obvious.Sediment on the dry beach erodes heavily,and the shoreline moves landward over a long distance.With the increase in the width and size of the dry beach,the wave height at the bottom of the backshore profile decreases,the wave height attenuation rate increases continuously,and the wave elimination effect is remarkable.When the storm incident wave intensifies,the wave height attenuation rate of the nourished dry beach decreases,indicating that the smaller the storm intensity is,the more significant the wave reduction effect of the nourished dry beach is.At the same time,different profile arrangements of nourished dry beaches suffer from different degrees of erosion under storm conditions,with significant changes in profile morphology.With intensified storm action,the intensity of sediment erosion in the nourished dry beach increases,the nourishment is weakened,and the recovery effect of the profile after the storm is not obvious.The results of the numerical modeling highlight that the dry beach nourishment method can resist storms to a certain extent,but the overall effect is relatively limited.

Effect of Natural Disasters and Their Coping Strategies in the Kuakata Coastal Belt of Patuakhali Bangladesh

Bangladesh has experienced a number of severe natural disasters. Most recently, tropical storms Aila, Sidr and Mohaseen have affected the Kuakata coastal belt. These natural disasters have had substantial negative impacts on natural resources. Development of coping strategies for the protection of natural resources across this belt is significantly important. The present research is focused on the effects of tropical storms on crops, humans, fish, livestock and infrastructure. There were 99 fatalities recorded during the Sidr and Aila natural disasters. These disasters impacted 910.94 ha (Sidr) and 973.69 ha (Aila) of cropland. The total number of affected livestock and fishes such as, 18,200 fish ponds, 1209 cattle, 3324 goats, 6888 chickens, 1716 ducks, 103 buffalo and 144 sheep. After tropical cyclones of Sidr, Aila, Heavy rainstorms and Mohaseen 12,970, 17,703, 10,050 and 2500 households respectively reported some form of damage. Cattle, goat, chicken and buffalo were found more injured than other livestock due to the natural disasters of Sidr. Temperature and wind speed were both found to be statistically significant (p ≤ 0.05) with humidity. Climatic parameters trend has been increased significantly since 1979. Regular monitoring of climatic variables, preparedness activities, and coping strategies would be significantly important for this coastal communities.

Types of Natural Disasters

A natural disaster is a major environmental event that can cause damage to property or loss of life.It is the result of disturbances in the natural processes of the Earth.Hurricanes are violent storms with fierce gusts of wind.Tornadoes and cyclones are also violent windstorms,usually with strong circular movements of wind.

System Development for Storm Surge Hazard Assessment Based on WebG IS for Tianjin Binhai New Area

It is imperative to develop a risk assessment system for quickly predicting storm surge disaster due to the vulnerability of Tianjin Binhai New Area. The flood routing model with user-defined breaches was firstly estab- lished based on the seed spread algorithm in order to achieve a rapid forecasting of storm surge flood information. Furthermore, fuzzy mathematics was utilized to identify the storm disaster grade, and the hazard mapping was con- ducted to visually obtain the hazard spatial and temporal distribution. Finally, the flood routing visuaUzation method was proposed based on numerical simulation of storm surge to achieve the reappearance scene of dynamic evolution process. The developed system can play a vital role in the management and decision-making of sea dyke mitigation engineering in Tianjin Binhai New Area.

1300—2019年江苏沿海风暴潮灾害时空分布特征

历史上江苏沿海曾频发2类风暴潮灾害,给当地带来了巨大损失。建立该地区长时间尺度的风暴潮灾害序列对了解过去与预测未来意义重大。以历史文献、地方志、海洋灾害公报等记载的风暴潮资料为基础,建立了风暴潮灾害识别体系,重建了1300—2019年江苏沿海风暴潮灾害序列,分析了风暴潮灾害时空变化规律,探究了其与气候异常和黄河、长江入海口变迁之间的关系。结果表明:江苏沿海地区主要受台风风暴潮灾害的影响,1300—2019年间共发生246次风暴潮灾害,平均周期为2.9年,且近100年来发生频率有增大的趋势;小波分析结果显示,风暴潮灾害年际变化存在17年、61年和115年的时间尺度周期,其中115年周期最为明显。海气相互作用影响下,厄尔尼诺活跃年江苏沿海台风风暴潮灾害偏少;气温与台风风暴潮灾害频次有一定的正相关性,但其影响机制尚不明确。盐城、南通和苏州为风暴潮灾害高发地区,常州和无锡发生频率较小。在气候变暖与江苏海岸冲淤变化的作用下,1855年后盐城和南通地区风暴潮灾害发生频率增加,连云港地区明显增加;随着海岸线的变迁与长江河口的演变,镇江、扬州、泰州与苏锡常地区受风暴潮灾害影响减少。

基于韧性视角的福建沿海风暴潮风险综合评估研究

本文基于城市安全韧性三角形模型,构建韧性城市视角下的风暴潮灾害综合风险评价框架,采用2011—2020年福建省33个沿海县(区、市)数据,通过城市适灾韧性评价指标体系,科学评价福建沿海城市适灾韧性水平时空分异特征,借助地理信息分析工具,综合风暴潮灾害危险性、脆弱性和城市韧性的评价结果,实现福建省域尺度风暴潮灾害综合风险区划。结果表明:(1)福建省2020年沿海城市适灾韧性水平从高到低依次为:福州、厦门、漳州、泉州、宁德、莆田;(2)随着各沿海城市适灾韧性水平的稳步提升,福建省风暴潮灾情等级指数呈下降趋势;(3)风暴潮综合风险I级区主要分布在莆田的兴化湾、湄洲湾沿岸;(4)在灾害防御建议方面,应重点关注河口、喇叭型湾口等地区,应重点防范北部路径和中部路径的台风风暴潮,应因地制宜制定海洋防灾减灾对策和韧性城市建设规划。

协同治理视角下海洋灾害经济损失的影响分析

协同治理机制是强调政府内部各主体间及政府与非政府等多元主体间基于利益共同体需要,彼此间建立信赖的关系,达到协作治理优势的公共管理过程。提升政府间跨部门协同治理能力是完善国家风暴潮灾害治理体系和实现灾害治理能力现代化的重要举措,也是政府完善公共管理的趋势所在。本文依托国家相关公报成果,在海洋公共管理范围内选择海洋灾害中最具特点的风暴潮灾害这一特定灾种作为研究,并选取受风暴潮灾害影响较大的浙江省作为研究区域,根据浙江省以往重大风暴潮灾害案例主体情况,分析各相关主体应对风暴潮灾害的具体措施,探索参与应对主体的现状及主体之间的协作问题,找出造成该问题的原因,进一步研究并提出应对主体间协同治理的对策和建议,以期为进一步开展我国沿海地区风暴潮灾害防灾减灾应急管理提供思路,提高多元主体对风暴潮灾害应急管理工作的认识。

极端天气下轨道交通水害致灾因子时空分布特征

近年来,在与气候变化相关的多种极端天气因素的相互作用下,洪涝事件对城市及轨道交通系统造成了严重影响。以粤港澳大湾区典型沿海城市洪涝事件为例,研究了轨道交通水害的主要致灾因子(极端降雨和台风风暴潮)及相关特征参数,揭示了其时空分布特征。研究表明:①近年来,广州市降雨量、降雨强度均明显增加,但降雨历时减少,降雨整体呈现增多且趋于集中的极端化趋势。广州市降雨时间分布在年内存在两个极值区间,第一极值区间与广州市“龙舟水”相关,第二极值区间主要受台风影响。广州市降雨空间分布不均,主要受季风及地理位置影响。②近10 a影响广东省的29场台风风暴潮灾害集中发生在7~10月,该时间与降雨第二极值区间重合。在对近年广东省典型轨道交通水害事件进行总结后发现,水害高发期与两个极值区间重合。虽然广东省台风强度存在缓慢降低趋势,但由于广东省沿海城市遭受台风风暴潮灾害的频次不断上升,且粤中地区密集分布有广东省全部的地下轨道交通系统,未来广东省轨道交通系统水害风险将随着极端天气时空分布特征的变化进一步加大。研究成果可为未来城市轨道交通水害致灾特征研究提供依据,为城市防灾减灾提供参考。

气候变化背景下珠江口地区台风风暴潮和流域洪水遭遇事件的风险探究

珠江三角洲是我国开放程度最高、经济活力最强的区域之一,该地区易受超强台风风暴潮和流域特大洪水等极端事件的侵袭,其复合作用的风险也不可忽视。全球气候变化更是增添了珠江三角洲地区防洪安全的复杂性。系统分析珠江口地区复合洪水的发生条件与致灾风险,提出精准防灾减灾措施,对保障珠江三角洲地区的长治久安和可持续发展具有重要意义。本研究表明,珠江口地区的台风风暴潮和流域洪水的间隔窗口期呈逐步缩小趋势,二者叠加产生复合灾害的潜在风险呈逐步增加趋势。

基于社交媒体数据的城市暴雨洪涝灾害风险评估——以郑州市“7·20”暴雨事件为例

近年来强降雨引发的城市洪涝灾害事件趋多,严重危害了人民的生命健康和财产安全,而客观、准确地开展城市暴雨洪涝灾害风险评估对于有效提升防灾减灾水平至关重要。但是,城市灾害点部分基础数据资料的缺失和滞后限制了城市暴雨洪涝灾害风险评估结果的准确性。随着移动互联技术的发展,民众在社交媒体上发布的相关灾害信息逐渐汇集成一种具有海量、时效性强和主题明确等特征的社交媒体数据资源,将其引入城市暴雨洪涝灾害风险评估工作对于准确刻画城市暴雨洪涝灾害的全貌无疑具有显著意义。以2021年郑州市“7·20”暴雨事件为例,首先从气象因素、基础地理信息、社会经济因素三方面选取了13个影响因子,然后基于爬虫技术获取微博数据中的内涝点信息,最后基于GBDT、XGB、RF和AdaB 4种机器学习模型对郑州市“7·20”暴雨洪涝灾害进行风险评估。结果表明:①基于上述模型得到的4组指标权重具有统计意义上的一致性,在各影响因子中,道路密度、植被覆盖指数、半小时最大降雨量和日最大降雨量在4组指标重要性排序中均位列前5,表明上述影响因子是本次暴雨洪涝灾害的主要致灾因素;②基于皮尔逊相关系数检验发现上述4种模型评估结果间的相关程度较高,所得出的极高风险区均集中在郑州市五大主城区的中心部分、中牟市东北部、新密市米村镇及城关镇、巩义市巩义站周边;③上述4种模型的AUC和ACC值均超过0.7,证实了机器学习模型在城市暴雨洪涝灾害风险评估中的有效性;相较于GBDT、XGB和RF模型,AdaB模型的评估结果精度最高,且得到的高风险与极高风险区的Rei值之和最大,表明其评估结果与实际情况相符。本研究通过将社交媒体数据引入城市暴雨洪涝灾害风险评估工作有效地提升了评估结果的准确性,可为郑州市及其他城市在类似强降水事件下的洪涝灾害风险预警和应急处置提供决策依据。

Crowdsourcing intelligence for improving disaster forecasts

INTRODUCTION.Natural disasters,including floods,storms,and tsunamis,pose a great threat to human societies.A recent study highlighted this concern,revealing that billions of people globally were exposed to flood hazards.1 In 2023,Super Typhoon Doksuri caused devasting floods in Beijing and Hebei areas,resulting in massive casualties and huge economic losses.Therefore,there is a need for a precise understanding of disaster processes,reliable forecasting of disaster effects,and timely warning of risks to prevent and mitigate major disasters.2 Numerical modeling stands as the predominant approach to meet these demands.However,the predictive accuracy of such numerical models could be degraded because of various factors:oversimplification of real processes,computational errors,fluctuations of complex environments(e.g.,terrains,precipitations,buildings,and plants),and the influence of human activities(e.g.,evacuation and rescue)during disasters.

考虑移动储能的风雨灾害配电网弹性提升方法

以台风和暴雨为代表的极端自然灾害会导致配电网大规模故障。为减小故障损失,提出一种计及风雨联合灾害下考虑移动储能的配电网弹性提升方法。首先,量化台风和暴雨灾害对配电网造成的影响,构建风雨联合灾害下的配电网故障率模型并基于系统信息熵筛选典型故障场景;其次,以灾害期间切负荷经济损失最小为目标,建立混合整数二阶锥规划模型,提出计及弹性提升的移动储能运行调度方法;最后,通过仿真算例对所提方法的有效性进行验证。结果表明,本文所提方法能有效提升配电网弹性,减少停电带来的经济损失。

A comparison of burn related injuries following the natural disaster Super Storm Hurricane Sandy to the National Burn Repository of the American Burn Association

Background:Burn related injuries from natural disasters are not wel described and natural disasters are not identified as an etiology of burn injury in the National Burn Repository(NBR)of the American Burn Association.The natural disaster Super Storm Hurricane Sandy had devastating effects.Our goal was to detail the burn related injuries fol owing this natural disaster and to compare the data to the NBR.Methods:This was a retrospective chart review of thirty four patients who sustained burn related injuries following Super Storm Hurricane Sandy(SSHS)and were managed at Staten Island University Hospital Burn Center.Institutional Review Board approval was obtained.Data variables included age,gender,race,past medical history(PMHx),burn type,percentage total body surface area(%TBSA),hospital length of stay(HLOS),and mortality.We compared data from SSHS to the 2003-2013 NBR.Categorical data were summarized using frequency counts,percentages and Clopper-Pearson 95%confidence interval for proportion.Continuous outcome data were summarized by descriptive statistics.Data analyses performed with SAS?System Version 9.3(SAS Institute Inc.,Cary,NC)and p<0.05 was significant.Results:In the SSHS group,average age was 36+24 years,range 1-80 years,and 44.1%were males(15/34,95%CI:27.2-62.1).Caucasians comprised 58.8%,(20/34,95%CI:40.7,75.4)and 73.5%had no PMHx(25/34,95%CI:55.6,87.1).The most common burn type was scald,55.9%,(19/34,95%CI:37.9,72.8)and%TBSA ranged 1%–47%,average of 7%+12%.The average HLOS was 13+26 days,range of 1–113 days.Mortality was 2.9%(1/34,95%CI:0.07–15).In comparison,the NBR reported an average age of 32 years and 69%were males.Caucasians comprised 59.1%.The most common burn type was flame,43.2%and the%TBSA ranged 1%–9.9%.HLOS ranged 8.4–10.2 days and mortality was 3.4%.Conclusion:We conclude that burn related injuries following a natural disaster differ as compared to those most commonly reported in the NBR.

天津市暴雨内涝灾害风险分析

分析了城市化对暴雨内涝灾害风险分布的影响 ,介绍了天津市暴雨内涝灾害仿真模型的基本原理及实际暴雨过程的验证情况。在分析天津市暴雨频次分布的基础上 ,根据天津市的暴雨特点和汛期排水运作规则 ,利用天津市内涝灾害仿真模型 ,对不同类型的降水过程进行了数值模拟 ,并对暴雨引起内涝灾害的风险进行了初步的量化评估。