共查询到19条相似文献，搜索用时 609 毫秒
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通过阐明水利防洪工程系统洪灾风险模型,揭示并验证洪水演进中有关水利工程建筑(水库及堤防)对洪灾影响。结果表明:对整个区域洪水实施防治时,在合理位置建造分蓄洪工程可降低整个防洪系统洪灾风险;通过减小水库下泄流量,增大其蓄洪量使得大坝洪灾发生风险增大,然而合理的蓄滞洪水方案可有效降低防洪系统洪灾发生风险;增大重点堤防可靠性(即防洪安全性)可降低整个防洪系统洪灾发生风险。 相似文献
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通过对长江洪水的致灾性、河道边界条件及其孕灾性、承载体易损性的分析,论述了长江中游为我国洪灾高危险区的必然性。分析了人类对河流的治理,使河道稳定性增加,减少了洪灾的风险,但是长江中游的局部河段却发生洪水位增高的趋势,又增加了洪灾风险,该区域高危险的基本特性犹存。研究了三峡运行后,长江中下游出现新的防洪形势:一方面三峡水库巨大的防洪库容拦蓄洪水,大大减少了中下游的洪灾,另一方面因河道的强冲刷,使河势变化剧烈、横向摆动增强,局部河段岸壁失稳,又增加防洪压力。同时因总体水面比降趋平,洪灾风险有向下游转移的趋势。未来长江中游仍为洪灾高危险区,仍应给予高度重视。 相似文献
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水库洪水调度中的风险分析方法 总被引：5，自引：0，他引：5
讨了水库洪水调度中洪水风险分析计算方法，分析了影响泄洪风险的不确定性因素，给出了随机变量的分布函与参数。结合实例，计算了水库洪水量优放水过程中对下游防地象造成的洪灾风险率。 相似文献
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分析梳理了防洪减灾风险、风险及其分析、风险管理和治理等概念,指出防洪减灾理念从20世纪早期的"控制洪水"到20世纪后期的"减小洪灾损失"再到21世纪初的"降低洪灾风险"的演变,与防洪减灾形势、社会公共管理水平等密切相关;防洪减灾风险源于洪水时空变化的不确定性、承灾体的不确定性和防灾减灾措施实际效果的不确定性等,需要根据具体问题做具体分析;防洪减灾风险管理指采取多方参与方式,在洪灾发展周期的不同阶段,针对多种不确定性,综合分析各种风险,力求做出相对科学的决策。在防洪减灾风险管理的研究和实践中,应重视有关人文因素及其不确定性、构建风险分析文化的重要性。 相似文献
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基于GIS的洪灾遥感监测与损失风险评价系统 总被引：9，自引：0，他引：9
洪灾遥感监测与损失风险评价系统,是以RS和GIS为技术支撑平台,由洪水灾害信息接收与采集,洪水灾害模拟和洪水灾害损失组成的较完整的系统,将数据库与模型库集成,当系统接受和采集了实时获取的洪水灾害的遥感监测与常规观测的信息后,通过图像处理与信息融合,能迅速确定洪水灾情在空间和时间上的分布,实时地提供洪水淹没范围并估算经济损失,为专家调度决策、指挥救灾抗灾工作提供科学依据。 相似文献
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Adaptation to climate change, particularly flood risks, may come to pose large challenges in the future and will require cooperation among a range of stakeholders. However, there presently exists little research especially on the integration of the private sector in adaptation. In particular, recently developed state programs for adaptation have so far been focused on the public sector. Insurance providers may have much to contribute as they offer other parts of society services to appropriately identify, assess and reduce the financial impacts of climate change-induced risks. This study aims to explore how the institutional distribution of responsibility for flood risk is being renegotiated within the UK, Germany and Netherlands. Examining how the insurance industry and the public sector can coordinate their actions to promote climate change adaptation, the study discusses how layered natural hazard insurance systems may result from attempts to deal with increasing risks due to increasing incidences of extreme events and climate change. It illustrates that concerns over the risks from extreme natural events have prompted re-assessments of the current systems, with insurance requiring long-term legislative frameworks that defines the objectives and responsibilities of insurers and the different political authorities. 相似文献
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Nigel W. Arnell 《Geoforum》1984,15(4):525-542
The National Flood Insurance Program (NFIP) both provides flood insurance to floodplain occupants and encourages local communities to adopt floodplain land-use regulations. As well as providing the core of the federal non-structural flood hazard management effort, the NFIP is a central element in both state and local activities. A major issue influencing the success of the NFIP in curbing flood damages is its treatment of properties built before the adoption of floodplain regulations. The potential for using the NFIP to encourage floodproofing and influence post-flood hazard mitigation must be fully explored. 相似文献
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Duration is a key characteristic of floods influencing the design of protection infrastructures for prevention, deployment of rescue resources during the emergency, and repartition of damage costs in the aftermath. The latter financial aspect mainly relies on the insurance industry and allows the transfer of damage costs from the public sector to the private capital market. In this context, the cost of catastrophes affecting a large amount of insured properties is partly or totally transferred from insurance companies to reinsurance companies by contracts that define the portion of transferred costs according to the temporal extent of the flood events synthesized in the so-called hours clause. However, hours clauses imply standard flood event durations, such as 168 h (1 week), regardless of the hydrological properties characterizing different areas. In this study, we firstly perform a synoptic-scale exploratory analysis to investigate the duration and magnitude of large flood events that occurred around the world and in Europe between 1985 and 2016, and then we present a data-driven procedure devised to compute flood duration by tracking flood peaks along a river network. The exploratory analysis highlights the link of flood duration and magnitude with flood generation mechanism, thus allowing the identification of regions that are more or less prone to long-lasting events exceeding the standard hours clauses. The flood tracking procedure is applied to seven of the largest river basins in Central and Eastern Europe (Danube, Rhine, Elbe, Weser, Rhone, Loire, and Garonne). It correctly identifies major flood events and enables the definition of the probability distribution of the flood propagation time and its sampling uncertainty. Overall, we provide information and analysis tools readily applicable to improve reinsurance practices with respect to spatiotemporal extent of flooding hazard. 相似文献
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Application of Remote Sensing in Flood Management with Special Reference to Monsoon Asia: A Review 总被引：4，自引：1，他引：4
The conventional means to record hydrological parameters of aflood often fail to record an extreme event. Remote sensingtechnology along with geographic information system (GIS)has become the key tool for flood monitoring in recent years.Development in this field has evolved from optical to radarremote sensing, which has provided all weather capabilitycompared to the optical sensors for the purpose of flood mapping.The central focus in this field revolves around delineation of floodzones and preparation of flood hazard maps for the vulnerable areas.In this exercise flood depth is considered crucial for flood hazardmapping and a digital elevation model (DEM) is considered to bethe most effective means to estimate flood depth from remotelysensed or hydrological data. In a flat terrain accuracy of floodestimation depends primarily on the resolution of the DEM. Riverflooding in the developing countries of monsoon Asia is very acutebecause of their heavy dependence on agriculture but any floodestimation or hazard mapping attempt in this region is handicappedby poor availability of high resolution DEMs. This paper presents areview of application of remote sensing and GIS in flood managementwith particular focus on the developing countries of Asia. 相似文献
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Mabel C. Marulanda Omar D. Cardona Miguel G. Mora Alex H. Barbat 《Natural Hazards》2014,74(3):2071-2088
Understanding and evaluating disaster risk due to natural hazard events such as earthquakes creates powerful incentives for countries to develop planning options and tools to reduce potential damages. The use of models for earthquake risk evaluation allows obtaining outputs such as the loss exceedance curve, the expected annual loss and the probable maximum loss, which are probabilistic metrics useful for risk analyses, for designing strategies for risk reduction and mitigation, for emergency response strategies and for risk financing. This article presents, based on probabilistic risk models, the design and implementation of a risk transfer instrument to cover the private buildings of the city of Manizales, Colombia. This voluntary collective instrument provides financial protection to both, the estate tax payers and the low-income homeowners through a cross-subsidy strategy; besides, it promotes not only the insurance culture but also the solidarity of the community. The city administration and the insurance industry are promoting this program using the mechanism of the property tax payment. This collective insurance helps the government to access key resources for low-income householders recovery and improve disaster risk management at local level. 相似文献
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Thanks to modelling advances and the increase in computational resources in recent years, it is now feasible to perform 2-D urban flood simulations at very high spatial resolutions and to conduct flood risk assessments at the scale of single buildings. In this study, we explore the sensitivity of flood loss estimates obtained in such micro-scale analyses to the spatial representation of the buildings in the 2D flood inundation model and to the hazard attribution methods in the flood loss model. The results show that building representation has a limited effect on the exposure values (i.e. the number of elements at risk), but can have a significant impact on the hazard values attributed to the buildings. On the other hand, the two methods for hazard attribution tested in this work result in remarkably different flood loss estimates. The sensitivity of the predicted flood losses to the attribution method is comparable to the one associated with the vulnerability curve. The findings highlight the need for incorporating these sources of uncertainty into micro-scale flood risk prediction methodologies. 相似文献
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Lixin Yi Ke Cheng Xiaoying Cao Yueling Sun Xiaoqing Cheng Ye He 《Natural Hazards》2017,85(2):1223-1248
Flood management consists many aspects such as hazard assessment, vulnerability assessment, exposure assessment, risk assessment, early warning system, damage assessment as well as risk mitigation planning. Conventional flood management are depending on the ground based monitoring of rainfall and river discharge. Many parts of the world are not covered by these sensor networks in one hand and these ground based systems are costly. Most of the tropical countries have high flood risk and low financial and institutional capacity to afford ground based system. While conventional flood management is time and cost intensive, spaceborne remote sensing provides timely and low-cost data in comparison to field observation, and is the obvious choice for most developing countries affected by flooding. Many aspects of flood management are being aided with the advancement of remote sensing technology. More precise and near real time flood detection, lead time in flood early warning system, accurate and advance inputs of hydrological models are now blessed by space technology. Many methods and approaches have been developed to overcome the constrains in the application of spaceborne remote sensing in flood management. Application of satellite remote sensing in flood hazard assessment is well documented, however, the application of space technology in other aspects of the flood management is also promising. Therefore, this review paper focuses on the applicability of spaceborne remote sensing and in most of the aspects in flood management.
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The production of flood hazard assessment maps is an important component of flood risk assessment. This study analyses flood hazard using flood mark data. The chosen case study is the 2013 flood event in Quang Nam, Vietnam. The impacts of this event included 17 deaths, 230 injuries, 91,739 flooded properties, 11,530 ha of submerged and damaged agricultural land, 85,080 animals killed and widespread damage to roads, canals, dykes and embankments. The flood mark data include flood depth and flood duration. Analytic hierarchy process method is used to assess the criteria and sub-criteria of the flood hazard. The weights of criteria and sub-criteria are generated based on the judgements of decision-makers using this method. This assessment is combined into a single map using weighted linear combination, integrated with GIS to produce a flood hazard map. Previous research has usually not considered flood duration in flood hazard assessment maps. This factor has a rather strong influence on the livelihood of local communities in Quang Nam, with most agricultural land within the floodplain. A more comprehensive flood hazard assessment mapping process, with the additional consideration of flood duration, can make a significant contribution to flood risk management activities in Vietnam. 相似文献
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如何快速,有效地进行投保户洪涝灾害损失评估是保险行业急需解决的一个重要课题.从洪涝灾害的成灾机理出发,针对保险公司对具体受灾体理赔需求,提出了计算每个投保户洪灾损失率方法,建立基于遥感(RS)和地理信息系统(GIS)的城市财产保险洪涝灾害损失评估模型.建模时较全面地考虑了与投保物性质有关的承灾体易损度和与投保物所处环境有关的地基承载力等因素,并使用RS/GIS将其定量化提取.最后使用广东省深圳市洪灾数据进行模型检验.验证结果表明,模型对于各个投保户均能得到较好的精度. 相似文献