基于GIS和OREMS的洪灾避难系统

面对突发的灾害,人类采取避难转移的方式来减少生命和财产的损失。大范围的人口转移是一个十分复杂的过程,必须有合理的计划和有效地利用现有的交通设施。提出了基于GIS和OREMS的洪灾避难系统来模拟洪灾的避难转移过程。根据洪灾危险区的统计资料,应用基于GIS的风暴潮洪灾风险系统分析洪灾淹没范围、避难区域的人口分布、路网结构,使用OREMS避难交通模型模拟避难过程。以长兴岛为例进行洪灾避难交通模拟,得到避难耗费时间,路网拥堵路段,并且在分析模拟结果的基础上对避难计划进行优化。     

The impact of disasters on small business disaster planning: a case study

A major flood in 1997 forced the evacuation of Grand Forks, North Dakota and caused damage of USD 1 billion. Despite this recent disaster there is only marginal evidence of an increase in disaster recovery planning by businesses that experienced the flood. This finding is consistent with the results of other business-related disaster research. Statistical tests of survey results from 2003 indicate that there is a significantly higher rate of disaster recovery planning in businesses started since the 1997 flood than in businesses started before the flood and still in business. Such an outcome indicates a need for public policy actions emphasizing the importance of disaster planning. Improved disaster planning is an aid to business recovery and the results demonstrate the need for more widespread efforts to improve disaster recovery planning on the part of smaller businesses, even in areas that have recently experienced disasters.     

基于系统动力学模型的影剧院人员疏散策略

随着社会的发展,人们对生命的重视程度日益增强,大型公共场所临灾情况下人员疏散问题的研究也越来越有实际意义.分析以往影剧院火灾事故可以发现,不正确的疏散逃生行为所引起的通道堵塞,是导致人员大量伤亡的一个主要原因.根据系统动力学原理,应用STELLA系统软件,建立了基于粗网络模型的人员疏散模型.以影剧院发生火灾为例,分析了采取不同疏散策略所产生的避难效果差异,找出了最佳的疏散策略.所提研究方法和建立的模型,对于合理设计疏散路线和优化建筑物的出口与通道结构具有一定的实用价值.     

Optimisation patterns for the process of a planned evacuation in the event of a flood

ABSTRACT

The main purpose of the article is to develop an optimisation pattern for the process of a preventive evacuation of people from flood-risk areas (at the first sign of a flood), aimed at mitigating the negative effects of the flood performed through the application of modern computer tools. It has been assumed that the use of both GIS tools and apps for vehicle traffic modelling (the research includes the use of a method developed by the authors) in emergency procedures implemented in response to a flood may increase the efficiency of the anti-flood campaign (here: the evacuation of residents from flooded areas), and thus, it may also minimise the negative effects of the flooding itself. The article distinguishes 14 stages of research, which were chiefly completed by means of the following methods: distance-based accessibility, cumulative accessibility, the Enhanced Two-Step Floating Catchment Area Method (E2SFCA) and the Two-Step Floating Catchment Area Method (2SFCA), the vehicle routing method, algorithms by Dinitz, Edmonds-Karp, and Ford-Fulkerson, and a comparative method applied to draw a comparison between the actual state of affairs and the optimum condition determined by the aforementioned methods.     

Interactions between scientific uncertainty and flood management decisions: Two case studies in Colorado

Flood management policies in the United States rely on scientific information about the frequency and intensity of extreme precipitation and runoff. Yet, the available information is inherently uncertain because of the complexity of meteorological and hydrological processes. In mountainous areas, flood risk can vary greatly even within short distances depending on local climate, topography, soil characteristics, and land use. This paper describes two Colorado cases in which policy makers were presented with conflicting scientific estimates: revision of the Fort Collins floodplain map and modification of the Cherry Creek Dam. The case studies demonstrate that uncertainty can have substantial impacts on regulatory processes, public safety, and costs. The analysis considers the differing perspectives of various participants in the flood management processes, illustrating the interplay between uncertainties attributable to scientific issues and values issues. It suggests that attempts to provide a single “best” estimate do not necessarily meet the decision needs of all stakeholders. Conclusions indicate a need to improve communication about uncertainty when scientific estimates areprovided to decision makers. Furthermore, in highly controversial decisions, it may be necessary to reframe the discussion to consider the values issues raised by scientific uncertainty.     

Heading for higher ground: factors affecting real and hypothetical hurricane evacuation behavior

Abstract

The purpose of this paper is to assess the determinants of hurricane evacuation behavior of North Carolina coastal households during Hurricane Bonnie and a future hypothetical hurricane. We use the data from a telephone survey of North Carolina coastal residents. Hypothetical questions are used to assess whether respondents will evacuate and where in the case of a future hurricane with varying intensities. We examine the social, economic, and risk factors that affect the decisions to evacuate and whether to go to a shelter or motel/hotel relative to other destinations. The most important predictor of evacuation is storm intensity. Households are more likely to evacuate when given evacuation orders, when they perceive a flood risk, and when they live in mobile homes. Households who own pets are less likely to evacuate. Non-white households, pet owners and those with more education are less likely to go to either a motel/hotel or shelter, preferring instead to stay with friends or family.     

荷兰的实时洪水管理：1993年和1995年洪水的比较研究

洪水灾害是影响荷兰经济持续发展的一个关键因素。本文详细介绍了荷兰的洪灾管理体系，并以１９９３年和１９９５年冬季洪水实时管理过程为例，分析比较了这两次洪水的政府管理行为的差异。     

Strategic regeneration: A policy coupling approach to managing a coastal resort in South Wales

This review paper takes a case study approach to critically discuss how regeneration in the coastal resort of Porthcawl, South Wales has integrated flood defences as part of a strategic spatial planning and integrated policy coupling approach to the redesign of the town's seaside, promenade and harbour quarter. This planned initiative is part of a concerted effort to upgrade the town's waterfront and enable regeneration of a small seaside resort. From a resort cycle perspective, Porthcawl's perceived vulnerability to changing economic fortunes has prompted a master planning approach which is intended to bring together a mixed-use development programme with particular attention to urban design, strategic environmental assessment and public consultation. In different ways, this process has sought to raise public awareness of the issues and risks associated with the town's coastal location and to integrate flood defence aspects within the strategic regeneration plan as part of a greater sensitivity to climatic risks and potential flooding. This paper examines the adaptive capacity of coastal communities and the complex of socio-economic and spatio-temporal perspectives that shape policy developments in the planning, development and proactive management of coastal environments. The paper identifies the need to accommodate a new civic awareness of potential environmental hazards in articulating the public interest and balancing the trade-offs involved.     

Urban riverbank residents' evaluation of flood evacuation policies in Winnipeg,Manitoba, Canada

The results of a discrete choice experiment (DCE) as a part of a survey among the urban riverbank residents on the Red River in Winnipeg, Manitoba, Canada, indicated that the risk of over-dike flooding, set at 2ft above the 1997 flood water level, was a significant determinant of both voluntary and mandatory evacuation, compared to those set at the 1996 or 1997 levels. Mandatory evacuation was more preferred over voluntary evacuation when the likelihood of flooding was at its most severe, and the opposite relationship was the case when the likelihood was low. The notification time for evacuation, suggested as 1, 2, and 4 days, proved to be an insignificant attribute, whereas the respondents indicated significant preference for full flood compensation over an offer of either 80% or 90% flood relief, irrespective of the alternatives of voluntary or mandatory evacuation.     

Decision‐making and evacuation planning for flood risk management in the Netherlands

A traditional view of decision‐making for evacuation planning is that, given an uncertain threat, there is a deterministic way of defining the best decision. In other words, there is a linear relation between threat, decision, and execution consequences. Alternatives and the impact of uncertainties are not taken into account. This study considers the ‘top strategic decision‐making’ for mass evacuation owing to flooding in the Netherlands. It reveals that the top strategic decision‐making process itself is probabilistic because of the decision‐makers involved and their crisis managers (as advisers). The paper concludes that deterministic planning is not sufficient, and it recommends probabilistic planning that considers uncertainties in the decision‐making process itself as well as other uncertainties, such as forecasts, citizens responses, and the capacity of infrastructure. This results in less optimistic, but more realistic, strategies and a need to pay attention to alternative strategies.     

Urban riverbank residents’ evaluation of flood evacuation policies in Winnipeg, Manitoba, Canada

The results of a discrete choice experiment (DCE) as a part of a survey among the urban riverbank residents on the Red River in Winnipeg, Manitoba, Canada, indicated that the risk of over-dike flooding, set at 2 ft above the 1997 flood water level, was a significant determinant of both voluntary and mandatory evacuation, compared to those set at the 1996 or 1997 levels. Mandatory evacuation was more preferred over voluntary evacuation when the likelihood of flooding was at its most severe, and the opposite relationship was the case when the likelihood was low. The notification time for evacuation, suggested as 1, 2, and 4 days, proved to be an insignificant attribute, whereas the respondents indicated significant preference for full flood compensation over an offer of either 80% or 90% flood relief, irrespective of the alternatives of voluntary or mandatory evacuation.     

Flood insurance and floodplain management: the US experience

Abstract

With over six million buildings located within the boundaries of the 100-yr floodplain, flood losses across the United States are widespread (88% of US counties experienced at least one flood disaster during the second half of the twentieth century). To deal with this problem, the federal government provides flood insurance through the National Flood Insurance Program, which was initiated by Congress in 1968 and amended significantly in 1969, 1973, and 1994. This article describes the US approach to flood insurance and notes a number of problems that have limited its effectiveness. Flood hazard identification is incomplete, and methods used are flawed. Mitigation has failed to contain increasing exposure to property damage in floods and coastal storms, and it has failed to markedly reduce exposure to loss of older buildings located in flood hazard areas. Market penetration of flood insurance is low, in spite of mandatory purchase requirements for new construction and the availability of subsidized insurance rates for older buildings located in flood-hazard areas. These problems, although serious, can be remedied through a variety of actions taken by governments at the federal, state, and local level.     

中国水灾风险综合管理--平衡大都市区水灾致灾强度与脆弱性

中国大都市区主要分布在大江大河的中下游地区,由于区域土地利用格局的巨大变化,特别是较多的水域和湿地因城市化而被占据,因此,一方面大都市区面临严重的洪水危险,另一方面为了使大都市区尽可能减轻洪水灾害,而加强了防洪能力的建设.然而,近50年的减灾实践证明,洪水灾害却在波动中趋于上升,即大都市区对洪水的脆弱性在增大.在对中国大都市区洪水灾害的区域分析基础上,以广东省为例,构造了综合水灾致灾因子和承灾体为一体的风险评估模型体系,以此提出了平衡大都市区水灾致灾强度与脆弱性的基本土地利用模式,和"政府-企业(社区)-保险公司"相结合的企业风险管理模式.     

Flood vulnerability and commercial activities: the case of the city of Girona, Spain

This paper is based on a case study of the city of Girona in Catalonia, Spain, and analyses the vulnerability of commercial establishments to floods caused by the Onyar River. A mapping and statistical approach (cluster analysis) was applied to the information obtained from 568 questionnaires answered by the shops and the workshops located in the flood risk area. The results obtained allowed the authors to determine five different flood vulnerability profiles of the commercial establishments analysed. These profiles paint a picture of little individual adaptation to the risk and the possibility of suffering, sooner or later, large economic losses due to overflowing of the Onyar River. The authors established a methodology for carrying out a detailed multidimensional analysis of the flood vulnerability of the city's commercial establishments in order to provide the foundations for local government policies and for strategies for shop owners to reduce flood vulnerability.     

Factors affecting the evacuation decisions of coastal households during Cyclone Aila in Bangladesh

Despite sincere efforts by concerned agencies and recent improvements in hazard warnings, thousands of at-risk people did not evacuate during Aila, a category-I tropical cyclone that struck southwestern coastal Bangladesh in 2009. This study investigated the responses of the people affected by Aila to cyclone warnings and associated evacuation orders, and unveiled behavioural aspects that explain why they did or did not comply with the evacuation orders. Utilising the primary data collected from 420 households living in the severely affected coastal sub-district Koyra, located in Khulna District, this study found that although more than 97% of the households had received cyclone warnings and evacuation orders before Aila's landfall, only around 26% had evacuated. We also examined this study's empirical findings for factors that had dissuaded people from complying with the evacuation orders. Relevant test statistics along with results from principal component analysis suggested that the significant and systematic absenteeism of households from disaster preparedness training appears to be one of the key determinants that affected their evacuation decisions, along with factors related to warning messages, the attributes of cyclone shelters, risk perception, and socioeconomic aspects. A number of recommendations are also presented in this study for people at risk to improve their evacuation rates in future emergencies, not only to save their own lives but also to save their livestock.     

荆江分洪区1998年洪水转移调查分析

对荆江分洪区１９９８年洪水期间安全转移的调查表明,叶然有分洪预案,但实际转移时仍出现了相当程度的拥挤与混乱。完善分洪转移的组织与管理,已成为分洪区居民１９９８年转移后关注的焦点,分洪区居民普遍表现出对分洪洪水情不甚了解,通过各种方式开展有关洪水的宣伟,提高区内居民的防洪意识,是荆江分洪区未来防洪减灾的重点工作之一,由于是国家为保护更重要的地区而主动分洪。对分洪区历分洪蒙受的损失给预某种形式的补偿已     

气候变化和人类活动对天津海岸带影响综述

21世纪全球海平面上升和区域地面沉降叠加所致的相对海平面上升速率存在加快趋势,将加剧天津沿海地区风暴潮、洪涝灾害和土地淹没的危害,影响沿海地区的城市抗灾功能、建筑物安全及生态资源。为此,本文综合讨论了气候变化导致的海平面上升和地面沉降对天津沿海风暴潮、海岸侵蚀以及港口码头的影响。建议滨海新区建设要高度重视海洋灾害的监测预警,提高沿海地区防潮和防汛工程的设计标准和城市抗灾能力,以有效实现滨海新区经济和社会可持续发展。     

Protecting Tourists from Death and Injury in Coastal Storms

Hurricanes, typhoons, tsunamis and other storms force thousands to flee coastal regions every year. In many cases, resort areas have been severely damaged and tourists placed in jeopardy. This article examines ways tourist businesses can and already have protected holiday-makers from coastal storm hazards through emergency evacuation and other measures. Using data from a sample of large and small hotels in New Orleans, Louisiana, we find considerable variation in protective behaviour. To explain this variation, we look at how perceptions and preparedness differ by both managerial and organisational characteristics. We then suggest a variety of measures that can be taken by hotels in coastal resort areas to reduce risk.     

Local perception of infrequent,extreme upland flash flooding: prisoners of experience?

The United Kingdom has experienced several exceptional summer flash floods in recent years and there is growing concern about the frequency of such events and the preparedness of the population. This paper uses a case study of the upper Ryedale flash flood (2005) and questionnaire and interview data to assess local perceptions of upland flash flooding. Experience of a major flash flood may not be associated with increased flood risk perception. Despite local residents’ awareness of a trend towards wetter summers and more frequent heavy rainfall, the poor maintenance of rivers was more frequently thought to be a more significant factor influencing local flood risk than climate change. Such findings have important implications for the potential success of contemporary national flood policies, which have put greater emphasis on public responsibility for responding to flooding. This study recommends, therefore, the use of fresh participatory approaches to redistribute and raise awareness of locally‐held flood knowledge.     

Household evacuation characteristics in American Samoa during the 2009 Samoa Islands tsunami

Tsunamis represent significant threats to human life and development in coastal communities. This quantitative study examines the influence of household characteristics on evacuation actions taken by 211 respondents in American Samoa who were at their homes during the 29 September 2009 M_w 8.1 Samoa Islands earthquake and tsunami disaster. Multiple logistic regression analysis of survey data was used to examine the association between evacuation and various household factors. Findings show that increases in distance to shoreline were associated with a slightly decreased likelihood of evacuation, whereas households reporting higher income had an increased probability of evacuation. The response in American Samoa was an effective one, with only 34 fatalities in a tsunami that reached shore in as little as 15 minutes. Consequently, future research should implement more qualitative study designs to identify event and cultural specific determinants of household evacuation behaviour to local tsunamis.