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1.
The European 7th Framework Programme project Extreme Weather impacts on European Networks of Transport devised a holistic analysis of extreme weather risks for the transport system. The analysis provided an overview of extreme weather risks, or a risk panorama. The risk panorama was built on a probabilistic approach to extreme weather phenomena occurrences and on vulnerability analysis based on selected macro-level economic and transport system indicators of the member states of EU-27. The panorama covers all transport modes and views infrastructure-related risks, time delay risks, and accidents risks. In addition to climatic circumstances, the devised risk indicator is also dependent on regional circumstances, such as population and transport density and income level. This paper describes the construct and application of an extreme weather risk indicator (EWRI). EWRIs are counted for each country and each transport mode separately. Furthermore, this paper also presents the most significant extreme weather events in different parts of Europe and on the transport modes they affect the most.  相似文献   

2.
Climate change is projected to increase the frequency and severity of extreme weather events. As a consequence, economic losses caused by natural catastrophes could increase significantly. This will have considerable consequences for the insurance sector. On the one hand, increased risk from weather extremes requires assessing expected changes in damage and including adequate climate change projections in risk management. On the other hand, climate change can also bring new business opportunities for insurers. This paper gives an overview of the consequences of climate change for the insurance sector and discusses several strategies to cope with and adapt to increased risks. The particular focus is on the Dutch insurance sector, as the Netherlands is extremely vulnerable to climate change, especially with regard to extreme precipitation and flooding. Current risk sharing arrangements for weather risks are examined while potential new business opportunities, adaptation strategies, and public–private partnerships are identified.  相似文献   

3.
The potential effects of climatic changes on natural risks are widely discussed. But the formulation of strategies for adapting risk management practice to climate changes requires knowledge of the related risks for people and economic values. The main goals of this work were (1) the development of a method for analysing and comparing risks induced by different natural hazard types, (2) highlighting the most relevant natural hazard processes and related damages, (3) the development of an information system for the monitoring of the temporal development of natural hazard risk and (4) the visualisation of the resulting information for the wider public. A comparative exposure analysis provides the basis for pointing out the hot spots of natural hazard risks in the province of Carinthia, Austria. An analysis of flood risks in all municipalities provides the basis for setting the priorities in the planning of flood protection measures. The methods form the basis for a monitoring system that periodically observes the temporal development of natural hazard risks. This makes it possible firstly to identify situations in which natural hazard risks are rising and secondly to differentiate between the most relevant factors responsible for the increasing risks. The factors that most influence the natural risks could be made evident and eventual climate signals could be pointed out. Only with this information can the discussion about potential increases in natural risks due to climate change be separated from other influencing factors and be made at an objective level.  相似文献   

4.
气候变化对陆地生态系统第一性生产力的影响研究综述   总被引：12，自引：0，他引：12  
气候变化对陆地生态系统第一性生产力(NPP)的影响是一个倍受关注的问题,目前从观测、实验和模拟等几个方面在不同层次上对这个问题进行了大量的研究。气候变化对生态系统NPP的影响取决于气候各因子及其组合变化的方向、生态系统与当前气候之间的关系,另外还要受养分及其它因子的影响。目前大量存在的NPP模型各有优缺点,模拟结果各异但有会聚的趋势。改进观测方法和理论、建立全球共享NPP数据库、进行大规模生态系统层次的实验研究和发展生态系统动态模型(DGVM)是未来一段时期研究的重点。  相似文献   

5.
Agriculture sector is exposed to a variety of risks and uncertainties which can lead to sizeable losses in crop yields and alter farm incomes. Risk management is, therefore, an essential element of the overall farm management process. Farmers have number of options in managing farm risks; however, smallholders, due to their small operations and limited financial capabilities, find it difficult to adopt sophisticated risk management strategies to overcome yield and income instabilities at farm level. This study is, therefore, designed to investigate the enabling environment for small farmers to manage climatic risks at farm level. A total of 330 sampled respondents from Khyber Pakhtunkhwa Province of Pakistan are randomly selected for the study using multistage sampling technique. Analysis of variance technique is employed to compare the risk management adoption decision of small, medium and large farmers. A post hoc analysis is also performed to highlight the difference in means and the magnitude of differences. The results indicate that smallholders have significantly lower access to credit (both formal and informal), formal information sources along with significantly higher perceptions of pest and diseases. Smallholders are also at the tail end in the adoption of precautionary savings and agricultural credit to manage climatic risk at farm level. The study urges for risk management policies particularly in favor of the small farmers and intervention in the existing information and credit provision programs to facilitate smallholders in managing farm risks.  相似文献   

6.
Accidents in underground collieries, under geological and geotechnical uncertainties, cause some irrecoverable consequences for workers. Recognizing and studying the effective factors in the occurrence of such accidents have a very crucial impact on improving worker safety and reducing mining costs. This paper introduces a new and beneficial technique named “modified risk priority number (MRPN)” for recognizing and assessing those risks which may cause working accidents in Iranian underground collieries. The available qualitative data from the mines was quantified using standard tables established for risk assessment. The technique was exemplified using data from mine accidents in Kerman and East-Alborz regions. Roof-fall was found to be the most significant risk factor in the mines that were investigated.  相似文献   

7.
A simulation chain for early prediction of rainfall-induced landslides   总被引：2，自引：1，他引：1  
A new simulation chain for early prediction of rainfall-induced landslides in unsaturated soils is presented. It includes a special computational weather code for forecasting the evolution of the synoptic weather and its changes due to interaction with the Earth’s surface (rainfall pattern), and a hydro-mechanical code to analyse rainfall effects on slope stability by computing degree of saturation and pore pressure changes due to rainwater infiltration. The linkage between these two numerical codes is ensured by an interface with the aim of bringing the data provided by the first code, which operates at basin or slope scale. The simulation chain can work in computational times that may be considered suitable for civil protection operations.  相似文献   

8.
A market place designed to provide a variety of weather-sensitive institutions with products for dealing with their risks from weather-climate hazards has been developing in recent years. Shifts in demographics, growing population, and greater wealth across the U.S., coupled with de-regulation of utilities and expansion of global economics, have increased corporate vulnerability to weather/climate extremes. Availability of long-term quality climate data and new technologies have allowed development of weather-risk products. One widely used by electric-gas utilities is weather derivatives. These allow a utility to select a financially critical seasonal weather threshold and for a price paid to a provider, to get financial payments if this threshold is exceeded. Another new product primarily used by the insurance industry is weather risk models. These define the potential risks of severe weather losses across a region where little historical insured loss data exists. Firms develop weather-risk models based on historical storm information combined with a target region’s societal, economic, and physical conditions. Examples of the derivatives and weather-risk models and their uses are presented. These various endeavors of the new weather market exhibit the potential for dealing with shifts in weather risks due to a change in climate.  相似文献   

9.
In liner shipping, the objective of a shipping company is to gain profits with a certain number of dispatched vessels and shipping costs depending on the shipping line conditions and market trends. In view of the current need to address global warming and reduce carbon emissions, the issue of greenhouse gases produced by shipping line operations should be considered in addition to profits. This study applied centralized decision making involving centralized data envelopment analysis for optimal resource allocation for each shipping line in order to achieve optimal output and undesirable output levels with reallocation of resources while using currently available resources. In the empirical analysis, this study sought to verify the resource allocation model for the intra-Asia lines of a Taiwanese shipping company by using the network centralized data envelopment analysis. The results showed that the proposed model provides shipping line operators with information on the amounts by which they should reduce undesirable outputs (carbon emissions), increase line revenue and revenue TEU-nautical mile, and reallocate resources. As such, the model can serve as a guide for resource allocation in shipping lines.  相似文献   

10.
Recent trends in climate modeling find in GRID computing a powerful way to achieve results by sharing geographically distributed computing and storage resources. In particular, ensemble prediction experiments are based on the generation of multiple model simulations to explore, statistically, the existing uncertainties in weather and climate forecast. In this paper, we present a GRID application consisting of a state-of-the-art climate model. The main goal of the application is to provide a tool that can be used by a climate researcher to run ensemble-based predictions on the GRID for sensitivity studies. One of the main duties of this tool is the management of a workflow involving long-term jobs and data management in a user-friendly way. In this paper we show that, due to weaknesses of current GRID middleware, this management is complex task. Those weaknesses made necessary the development of a robust workflow adapted to the requirements of the climate application. As an illustrative scientific challenge, the application is applied to study the El Niño phenomenon, by simulating an El Niño year with different forcing conditions and analyzing the precipitation response over south-American countries subject to flooding risk.  相似文献   

11.
Disaster risk assessment of ports based on the perspective of vulnerability   总被引：1，自引：1，他引：0  
Global environmental changes have led to frequent occurrences of climatic extremes. The increasingly frequent and high-magnitude natural disasters in Taiwan have caused significant mortality, injury, and property damage. In response, there have been requests to improve the capacity to cope with extreme climatic conditions through increased awareness and identification of vulnerability. Disruptions to transportation systems affect the resilience for sustaining daily operations. Among the various types of transportation systems, ports provide substantial employment and industrial activity, contributing to national and regional development. In addition, ports integrate the functions of supply chains such as services in logistics, information, and business, becoming the location of industrial clusters. Therefore, this study examines the risk of port failures from the perspective of vulnerability. Specifically, seven vulnerable factors derived from the extant literature and lessons learned from the previous disaster cases are evaluated using geographic information systems. The results reveal that port capacity and efficiency have a significant effect on port vulnerability in which the efficiency of gantry cranes, labor productivity, free trade zone business volume, and ground access networks play crucial roles in port failure. Moreover, the risks associated with port operation are evaluated by overlapping a hazard map of areas prone to debris flows and tsunami inundation. The risk maps can assist decision makers in understanding the vulnerability and adopting appropriate strategies to minimize disaster risks.  相似文献   

12.
吴丽  陈礼仪  吴飞 《探矿工程》2010,37(7):70-73
藏木水电站某标段边坡预应力锚固工程施工中面临众多的风险,且存在多种不确定因素,项目管理难度大。构建了项目风险评价指标体系,使用三标度法和层次分析法对指标进行权重分析,引入了模糊综合评判模型,将管理者和专家的经验由定性转为定量,对项目风险进行了定量化评价,评价结论为＂风险较大＂,为进一步制定项目管理方案提供了依据。  相似文献   

13.
Economic risk maps of floods and earthquakes for European regions   总被引：2，自引：0，他引：2  
Europe experiences different natural hazards and subsequent risks that have various effects on the development of its regions. The spatial significance of hazards can be expressed as an economic risk when combining hazard potential with vulnerability data. Two examples of European natural hazard maps on floods and earthquakes, as well as the resulting risk profiles of regions (combination of hazard potential and vulnerability) give a first impression on the spatial characters of hazards in Europe and their potential impact on further spatial development. The economic risk maps enable a view on the spatial dimension of the economic damage potential of flood and earthquakes, pointing out comparable situations across Europe with the aim to facilitate targeted responses and policies. The spatial character of a hazard is either defined by spatial effects that might occur in case of a disaster or by the possibility of spatial planning responses. The integration of the economic vulnerability of a region (regional GDP per capita, population density) leads to a classification of areas according to their economic risk or damage potential towards hazards. These synthetic risk profiles are presented as risk maps of European regions in administrative boundaries. Obtained information can be of interest for spatial planning and development strategies, e.g. economic risk profile of regions can influence the targets of investments and could thus be an important background for structural funding.  相似文献   

14.
The environmental effects of blasting must be controlled in order to comply with regulatory limits. Because of safety concerns and risk of damage to infrastructures, equipment, and property, and also having a good fragmentation, flyrock control is crucial in blasting operations. If measures to decrease flyrock are taken, then the flyrock distance would be limited, and, in return, the risk of damage can be reduced or eliminated. This paper deals with modeling the level of risk associated with flyrock and, also, flyrock distance prediction based on the rock engineering systems (RES) methodology. In the proposed models, 13 effective parameters on flyrock due to blasting are considered as inputs, and the flyrock distance and associated level of risks as outputs. In selecting input data, the simplicity of measuring input data was taken into account as well. The data for 47 blasts, carried out at the Sungun copper mine, western Iran, were used to predict the level of risk and flyrock distance corresponding to each blast. The obtained results showed that, for the 47 blasts carried out at the Sungun copper mine, the level of estimated risks are mostly in accordance with the measured flyrock distances. Furthermore, a comparison was made between the results of the flyrock distance predictive RES-based model, the multivariate regression analysis model (MVRM), and, also, the dimensional analysis model. For the RES-based model, R 2 and root mean square error (RMSE) are equal to 0.86 and 10.01, respectively, whereas for the MVRM and dimensional analysis, R 2 and RMSE are equal to (0.84 and 12.20) and (0.76 and 13.75), respectively. These achievements confirm the better performance of the RES-based model over the other proposed models.  相似文献   

15.
Jens-Uwe Klügel   《Earth》2008,88(1-2):1-32
The paper is dedicated to the review of methods of seismic hazard analysis currently in use, analyzing the strengths and weaknesses of different approaches. The review is performed from the perspective of a user of the results of seismic hazard analysis for different applications such as the design of critical and general (non-critical) civil infrastructures, technical and financial risk analysis. A set of criteria is developed for and applied to an objective assessment of the capabilities of different analysis methods. It is demonstrated that traditional probabilistic seismic hazard analysis (PSHA) methods have significant deficiencies, thus limiting their practical applications. These deficiencies have their roots in the use of inadequate probabilistic models and insufficient understanding of modern concepts of risk analysis, as have been revealed in some recent large scale studies. These deficiencies result in the lack of ability of a correct treatment of dependencies between physical parameters and finally, in an incorrect treatment of uncertainties. As a consequence, results of PSHA studies have been found to be unrealistic in comparison with empirical information from the real world. The attempt to compensate these problems by a systematic use of expert elicitation has, so far, not resulted in any improvement of the situation. It is also shown that scenario-earthquakes developed by disaggregation from the results of a traditional PSHA may not be conservative with respect to energy conservation and should not be used for the design of critical infrastructures without validation. Because the assessment of technical as well as of financial risks associated with potential damages of earthquakes need a risk analysis, current method is based on a probabilistic approach with its unsolved deficiencies.

Traditional deterministic or scenario-based seismic hazard analysis methods provide a reliable and in general robust design basis for applications such as the design of critical infrastructures, especially with systematic sensitivity analyses based on validated phenomenological models. Deterministic seismic hazard analysis incorporates uncertainties in the safety factors. These factors are derived from experience as well as from expert judgment. Deterministic methods associated with high safety factors may lead to too conservative results, especially if applied for generally short-lived civil structures. Scenarios used in deterministic seismic hazard analysis have a clear physical basis. They are related to seismic sources discovered by geological, geomorphologic, geodetic and seismological investigations or derived from historical references. Scenario-based methods can be expanded for risk analysis applications with an extended data analysis providing the frequency of seismic events. Such an extension provides a better informed risk model that is suitable for risk-informed decision making.  相似文献   


16.
Weather as a Chronic Hazard for Road Transportation in Canadian Cities   总被引：2，自引：1，他引：2  
Inclement weather creates a chronic hazard for Canadian travellers. Past studies indicate that road collision rates increase during precipitation, although the magnitude of theincrease varies from study to study, partly as a result of variations in weather and driving conditions,but also because of differences in methods. The goal of the current study is to improve ourunderstanding of the links between weather and travel risk in mid-sized Canadian cities by using astandardized method for analyzing data from six cities with different climates: Halifax-Dartmouth,Ottawa, Québec, Hamilton, Waterloo Region, and Regina. The study has four interrelated objectives: (1) Toconduct a sensitivity analysis to determine the extent to which risk estimates vary depending onthe criteria used to define precipitation events and `normal' conditions; (2) To compare therelative risk of collision and injury during precipitation relative to `normal' conditions; (3) Todetermine the extent to which weather-related risks vary fordifferent Canadian cities; and (4) To explore any differences in collision characteristics between events and controls, especially as theyvary from city to city. Results are based on a matched-pair analysis, using six-hour time blocks over afour-year period, 1995 to 1998. Results indicate only modest sensitivity to the criteria used to define precipitation events and `normal' conditions. On average, precipitation is associated with a 75 percentincrease in traffic collisions and a 45 percent increase in related injuries, as compared to `normal'seasonal conditions, but risk levels vary depending on the characteristics of the weather event.Both sensitivity to specific weather conditions and weather-related accident profiles vary from city tocity in ways that are not easily explained.  相似文献   

17.
Flyrock arising from blasting operations is one of the crucial and complex problems in mining industry and its prediction plays an important role in the minimization of related hazards. In past years, various empirical methods were developed for the prediction of flyrock distance using statistical analysis techniques, which have very low predictive capacity. Artificial intelligence (AI) techniques are now being used as alternate statistical techniques. In this paper, two predictive models were developed by using AI techniques to predict flyrock distance in Sungun copper mine of Iran. One of the models employed artificial neural network (ANN), and another, fuzzy logic. The results showed that both models were useful and efficient whereas the fuzzy model exhibited high performance than ANN model for predicting flyrock distance. The performance of the models showed that the AI is a good tool for minimizing the uncertainties in the blasting operations.  相似文献   

18.
Society requires increasingly that the hazard and risk associated with engineered constructions be quantified. The current paper presents geotechnical hazard assessment in the context of a risk framework. Concepts of uncertainties, reliability, safety and risk are briefly reviewed. The use of the approach is exemplified for offshore facilities, including piled foundations, jack-up structures, gravity foundations and underwater slopes. The applications demonstrate that probabilistic analyses complement the conventional deterministic safety factor and deformation-based analyses, and contribute to achieving a safe and optimum design. The probabilistic approach adds value to the results with a modest additional effort. The conclusions emphasize the usefulness of a risk assessment, the importance of engineering judgement in the assessment and the need for involving multi-disciplinary competences to achieve reliable estimates of hazard and risk. The profession can only gain by implementing probabilistic-based thinking and risk-based approaches more systematically than before.  相似文献   

19.
Recent accidents in underground structures have raised the risk awareness of the geotechnical engineering community. Geotechnical design is subject to significant uncertainties in load and strength parameters as well as in engineering models. However, engineering models which objectively address such uncertainties in design are still scarce. This paper presents an objective framework for the quantification of the risks involved in underground structures excavated in fractured rock masses, where structural failures may occur due to block falls. The framework considers the structure as a distributed system, where falling block probabilities are integrated over the main structural dimension. Random block size and geometry, arising from random joint orientation, are taken into account, as well as uncertainties in joint strength and geometrical parameters. A cost function is used to quantify failure consequences in terms of the block size. The framework is demonstrated in an application to a case study involving a real structure: the Paulo Afonso IV power station cavern. Results of the case study show that the studied cavern presents high reliability and very low risk. The framework proposed herein is shown to be a practical tool for the risk evaluation of underground structures constructed in rock masses, such as caverns and tunnels.  相似文献   

20.
Exposure to arsenic and fluoride through contaminated drinking water can cause serious health effects. In this study, the sources and occurrence of arsenic and fluoride contaminants in groundwater are analyzed in Dawukou area, northwest China, where inhabitants rely on groundwater as the source of drinking water. The triangular fuzzy numbers approach is adopted to assess health risk. The fuzzy risk assessment model incorporates the uncertainties that are caused by data gaps and variability in the degree of exposure to contaminants. The results showed that arsenic and fluoride in groundwater were mainly controlled by the dissolution–precipitation of Ca-arsenate and fluorite under weakly alkaline conditions. The arsenic and fluoride concentrations were higher in the shallow groundwater. The most probable risk values for arsenic and fluoride were 4.57 × 10?4 and 0.4 in the shallow groundwater, and 1.58 × 10?4 and 0.3 in the deep groundwater. Although the risks of fluoride were almost within the acceptable limit (<1.0), the risk values of arsenic were all beyond the acceptable levels of 10?6 for drinking water. Further, the local administration should pay more attention to the potential health risk through dietary intake and to the safety of deep water by ensuring it is not contaminated under prolonged pumping conditions. The fuzzy risk model treats the uncertainties associated with a quantitative approach and provides valuable information for decision makers when uncertainties are explicitly acknowledged, particularly for the variability in contaminants. This study can provide a new insight for solving data uncertainties in risk management.  相似文献   

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