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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Rockslides in a Changing Climate: Establishing Relationships Between Meteorological Conditions and Rockslides in Southwestern Norway for the Purposes of Developing a Hazard Forecast System

Dunlop, STEPHEN 09 February 2010 (has links)
The steep, mountainous terrain of southwestern Norway is prone to a high frequency of rockslides. It is known that many of these rockslides are triggered by meteorological conditions, yet there have been few studies dedicated to quantifying the link between rockslides and the runoff conditions and freeze/thaw processes that trigger failure. With recent climate research indicating that southwestern Norway will experience warmer temperatures and increased precipitation, it has become apparent that a better understanding of this link is required to help prepare for future events. Rockslides in Norway lead to road closures, property damage and fatalities every year, and one of the biggest challenges for Norwegian authorities is to react to rockslides as they happen and to reopen roads as soon as possible. This is especially true when several rockslides occur on the same day in multiple locations. As a result, authorities wish to implement a hazard mapping system that uses a weather forecast to predict when and where geohazards are likely to occur. To this end, this thesis is aimed at providing a rockslide forecast map that changes every day based on the weather forecast. By comparing a rockslide database to historic weather records, the work carried out for this thesis has indicated that extreme runoff during winter storms is responsible for triggering the majority of rockslides in the region. Using this knowledge as a basis, two potential hazard mapping systems are proposed, one based on trigger threshold exceedance and the other based on weights-of-evidence susceptibility mapping. Both of these methods operate by mapping areas experiencing extreme runoff conditions. Several runoff parameters were tested for possible inclusion, and it was found that 48-hr antecedent runoff, normalized by mean monthly precipitation had the best correlation with rockslide occurrence. Verification of these methods indicates that both approaches are successful in predicting days with extreme conditions, thereby alerting authorities that a high frequency of rockslides is likely. Due to the complex nature of rockslide triggering, it is not fully understood how climate change will affect future rockslide activity; however, this thesis attempts to answer these questions and to provide a basis for future studies. / Thesis (Master, Geological Sciences & Geological Engineering) -- Queen's University, 2010-01-28 08:12:43.316
2

Making Sense of Natural Hazard Mitigation: Personal, Social and Cultural Influences

Paton, Douglas, Sagala, Saut, Okada, Norio, Jang, Li J., Bürgelt, Petra T., Gregg, Chris E. 01 January 2010 (has links)
Worldwide, recognition of the growing risk faced by communities in many countries from natural hazard events has stimulated interest in promoting people's capacity to co-exist with often beneficial, but occasionally hazardous, natural processes by encouraging the adoption of preparedness measures. Starting from recognition that levels of hazard preparedness are generally low, this paper examines how people's decisions about hazard mitigation derive from how they interpret the hazards, their relationship with the hazards and the sources of information about hazards. It describes how interpretive processes at the person (outcome expectancy), community (community participation and collective efficacy) and societal (empowerment and trust) level interact to predict levels of hazard preparedness. The data support the argument that the effectiveness of public hazard education strategies community preparedness can be increased by integrating risk management activities with community development strategies. The cross-cultural validity of the model is discussed using data from communities in New Zealand, Indonesia and Japan. Testing the model across countries and hazards (e.g. earthquakes, volcanic hazards) supports its all-hazards and cross-cultural applicability. The theoretical (e.g. identifying the degree to which the processes that underpin how people respond to hazard threats are culturally equivalent) and practical (e.g. providing a common basis for collaborative learning and research between countries and providing risk management agencies in different cultures with access to a wider range of risk management options) implications of the cross-cultural equivalence of the model are discussed.
3

Natural Hazards In Mississippi: Regional Perceptions And Reality

Threatt, Patrick Lee 15 December 2007 (has links)
This study comprised of a survey of 807 students in geosciences classes at Mississippi State University to determine the perceived level of threat from eight natural hazards: hurricanes, hail, lightning, tornadoes, earthquakes, ice storms, floods, and wildfires. Responses were analyzed to detect spatial differences in perceptions of threats across the state of Mississippi for comparison. Actual occurrences of the natural hazards and preparations for dealing with these hazards were recorded by county and MEMA districts. Threat perceptions for hurricanes, ice storms, floods, and lightning showed spatial differences, whereas threats from hail, tornadoes, earthquakes, and wildfire showed no spatial differences. All perceived threats except ice storms paralleled the actual recorded occurrences of the respective hazards spatially. Preparations for each hazard included the adoption of MEMA’s Basic Plan for the entire state.
4

Master or Engineering Management Report. Lessons Learned, Disaster Mitigation Guidelines.

Johnston, Courteney January 2012 (has links)
The Master of Engineering Management Project was sponsored by the Canterbury Earthquake Recovery Authority (CERA) and consisted of two phases: The first was an analysis of existing information detailing the effects of hazardous natural events on Canterbury Lifeline Utilities in the past 15 years. The aim of this “Lessons Learned” project was to produce an analysis report that identified key themes from the research, gaps in the existing data and to provide recommendations from these “Lessons Learned.” The Second phase was the development of a practical “Disaster Mitigation Guideline” that outlined lessons in the field of Emergency Sanitation. This research would build upon the first stage and would draw from international reference to develop a guideline that has practical implementation possibilities throughout the world.
5

Quantifying and understanding the aggregate risk of natural hazards

Hunter, Alasdair January 2014 (has links)
Statistical models are necessary to quantify and understand the risk from natural hazards. A statistical framework is developed here to investigate the e ect of dependence between the frequency and intensity of natural hazards on the aggregate risk. The aggregate risk of a natural hazard is de ned as the sum of the intensities for all events within a season. This framework is applied to a database of extra tropical cyclone tracks from the NCEP-NCAR reanalysis for the October to March extended winters between 1950 and 2003. Large positive correlation is found between cyclone counts and the local mean vorticity over the exit regions of the North Atlantic and North Paci c storm tracks. The aggregate risk is shown to be sensitive to this dependence, especially over Scandinavia. Falsely assuming independence between the frequency and intensity results in large biases in the variance of the aggregate risk. Possible causes for the dependence are investigated by regressing winter cyclone counts and local mean vorticity on teleconnection indices with Poisson and linear models. The indices for the Scandinavian pattern, North Atlantic Oscillation and East Atlantic Pattern are able to account for most of the observed positive correlation over the North Atlantic. The sensitivity of extremes of the aggregate risk distribution to the inclusion of clustering, with and without frequency intensity dependence, is investigated using Cantelli bounds and a copula simulation approach. The inclusion of dependence is shown to be necessary to model the clustering of extreme events. The implication of these ndings for the insurance sector is investigated using the loss component of a catastrophe model. A mixture model approach provides a simple and e ective way to incorporate frequency-intensity dependence into the loss model. Including levels of correlation and overdispersion comparable to that observed in the reanalysis data results in an average increase of over 30% in the 200 year return level for the aggregate loss.
6

Three Essays on the Behavioral Responses to Coastal Hazards and Vulnerability

Jiang, Fan 15 May 2018 (has links)
This dissertation consists of three papers in environmental and natural resource economics. The first paper estimates the value of statistical lives (VSL) from hurricane evacuation behavior through an empirical analysis. I present empirical models that predict individuals' willingness to pay (WTP) for avoiding hurricane risks revealed through their evacuation behavior. Using survey data from Texas residents (who were affected by Hurricane Ike), I analyze the individuals’ hurricane evacuation decisions and their corresponding WTP for evacuation. I also estimate the individuals' WTP for avoiding hurricane risks under both voluntary and mandatory evacuation orders and calculate the associated VSL. The findings can be useful to emergency management agencies for evacuation planning. In the second paper, I study market responses to multiple hurricanes based on evidence from real estate sales data. Unlike earlier studies that examined the effect of hurricane exposures on property value, the present study considers how multiple hurricane hits affect the home value. I use repeat sales data from three counties in Florida from 2000 to 2010 and develop a hedonic price model. The findings identify the determinants that influence the property value and provide valuable insights for homebuyers and sellers. The study also provides useful insights regarding the benefits of hurricane mitigations to Florida residents and beyond. The third paper investigates the time preference and the dynamics of evacuation behavior based on evidence from Hurricane Ike and Hurricane Sandy. This paper contributes to the literature on households’ evacuation timing decisions by investigating the factors influencing people’s time preference for evacuation behavior. Unlike other studies, I examine the residents’ evacuation behavior across the Gulf coast as well as the Northeast and Mid-Atlantic coasts from a comparative perspective. I use one survey dataset from Texas residents who experienced Hurricane Ike and another survey dataset from the Northeastern and Mid-Atlantic US states that were affected by Hurricane Sandy. The results provide insights for future hurricane evacuation planning and emergency management.
7

Debris Hazard Assessment in Extreme Flooding Events

Stolle, Jacob 13 September 2019 (has links)
Coastal areas are often important to economic, social, and environmental processes throughout the world. With changing climate and growing populations in these areas, coastal communities have become increasingly vulnerable to extreme flooding events, such as tsunami, storm surges, and flash floods. Within this new paradigm, there has been an effort to improve upon current methods of hazard assessment, particularly for tsunami. Recently, the American Society of Civil Engineers (ASCE) released the ASCE 7 Chapter 6 which was the world’s first standard, written in mandatory language, that addressed tsunami resilient design in a probabilistic manner for several of its prescriptions. While often the focus tends to be on mapping the hazards related to hydraulic loading conditions, post-tsunami field surveys from disaster-stricken coastal communities have also shown the importance of also considering the loads exerted by solid objects entrained within the inundating flows, commonly referred to as debris loading. Limited research has addressed debris hazard assessment in a comprehensive manner. Debris loading can be generally divided into two categories: impact and damming. Debris impact loads are caused by the rapid strike of solid objects against a structure. Debris damming loads are the result of the accumulation of debris at the face of or around a structure, causing thus an obstruction to the flow. The primary difference between these loads is the time period over which they act. The rapid loading due to debris impacts requires structural properties be considered in assessing the associated loads whereas debris damming loads are generally considered in a quasi-static manner. In assessing the hazard associated with both impact and damming loading conditions, methodologies must be developed to consider the likelihood of the load occurring and the magnitude of that load. The primary objective of this thesis was to develop a probabilistic framework for assessing debris hazards in extreme coastal flooding events. To achieve this objective, the components of the framework were split into three general categories: debris transport, debris damming, and debris impact. Several physical experimental studies were performed to address each of these components, representing the most comprehensive assessment of debris hazards in extreme flooding events to date. Debris transport was addressed to estimate the likelihood of debris loading occurring on a structure. The studies presented herein examine the different parameters that must be considered in assessing the motion of debris with the flow. The studies showed that the initial configuration of the debris and hydrodynamic conditions were critical in determining the motion of the debris. The stochastic properties of the debris motion were also assessed. It was shown that the lateral displacement of the debris could be approximated by a Gaussian distribution and the debris velocity by a Kumaraswamy (1980) distribution. The study of debris impact was further used to develop the current models used in estimating the impact force. The rigid body impact model was compared to models where the structural response was considered. The analysis showed that the effective stiffness model proposed by Haehnel and Daly (2004) was best suited to provide a conservative estimation of the impact force. Additionally, the impact geometry was taken into consideration examining the influence of various parameters on the impact force. Furthermore, debris damming was examined for the first time in transient loading conditions. This particular study examined the influence of the transient wave condition on the debris dam formation as well as the influence of different debris geometries. The influence of the debris dam geometry was correlated to increases in loading and overtopping conditions at structures. The assessment of debris hazards is critical in the development of accurate design conditions. The probabilistic framework presented within this thesis is expected to provide a basis for estimating debris hazards and inform future studies in the development of hazard assessment models.
8

An investigation of the hazard associated with the alluvial fans on the Kaikoura Coast, South Island, New Zealand : a thesis submitted to the Victoria University of Wellington in fulfilment of the requirements for the degree of Master of Science (Honours) in Physical Geography /

Baylis, Erin Julia. January 2009 (has links)
Thesis (M.Sc.(Hons.))--Victoria University of Wellington, 2009. / Includes bibliographical references.
9

Evaluace přírodních ohrožení glaciálního jezera Imja, Nepál / Evaluation of natural hazards of glacial Lake, Nepal

Kroczek, Tomáš January 2019 (has links)
Current dynamic of global climate change is the trigger of new natural processes such as glacial lake outburst floods. One example is lake Imja located in the hinterland of Mt. Everest. Outburst of lake Imja would have undoubtedly negative impact on financial and cultural climate of attached area. This diploma thesis is focusing on the various factors and its imapct on the stability of moraine. The main aim of this thesis is to evaluate possibility of impact of rockfall into the lake, to monitor the development of its expansion in comparison with growing temperatures in last 60 years and also to assess the development of morphology of moraine containing dead ice. The results of the thesis indicate accelerating expansion of the lake at the expense of the Imja and Lhotse Shar glaciers, for which the rising means of temperatures of the months in the warm half of the year are particularly important. The results also show that there is no risk of producing wave after impact of rockfall into the lake, as the lateral moraines are sufficiently high to protect the lake. The crucial factor for the stability of the moraine dam is the melting of dead ice in its core, where new and new thermokarst lakes are forming on the surface of the moraine and a seepage through the moraine in its southwestern part has also...
10

Disaster risk reduction in the emirate of Abu Dhabi, United Arab Emirates : effects of natural and non-natural disasters over business continuity and sustainability / La prévention des risques dans l'Emirat d'Abu Dhabi, Emirats Arabes Unis : Impacts des catastrophes naturelles et non-naturelles sur les activités économiques et le développement durable

Al Marzooqi, Ahmed 28 September 2017 (has links)
Les catastrophes sont les produits d'une étroite relation entre les hommes et la nature. Le développement économique et social contribue à accroitre fortement la vulnérabilité aux catastrophes. Au-delà des motivations qui sont les siennes, les êtres humains ont élaboré des méthodes pour minimiser les effets désastreux de cette relation. De ce fait, étudier les risques associés aux catastrophes naturelles et non-naturelles permet de trouver des méthodes adaptées au suivi et à la gestion des risques tant concernant les facteurs naturels que les facteurs non-naturels. Cette recherche a pour but d'analyser la manière avec laquelle les processus de gestion des risques de catastrophes ont été mis en place dans l'émirat d'Abu Dhabi, aux Emirats Arabes Unis, par les différentes institutions responsables, qu'elles soient publiques ou privées. La vulnérabilité des Emirats Arabes Unis aux catastrophes s'accroit avec l'importance du développement des activités industrielles dans la période actuelle. De plus, les désastres liés à des mouvements tectoniques et aux phénomènes climatiques sont devenus très fréquents dans le pays. Au cours des années actuelles, différents types de catastrophes ont affecté la population des Emirats Arabes Unis et impacté les ressources des agences intergouvernementales qui sont chargés de la gestion des situations d'urgence en cas de catastrophes. L'étude permet de tirer différentes conclusions sur le fonctionnement du système de prévention et de gestion des risques dans l'émirats d'Abu Dhabi et aux Emirats Arabes Unis, mettant en avant les difficultés rencontrées pour la mise en place de réponses parfaitement adaptées aux problèmes rencontrés. Différentes recommandations sont enfin élaborées pour aller plus loin dans la réflexion sur la réduction et la gestion des risques naturels et non-naturels et sur l'élaboration de mesures adéquates. Il apparait alors que les procédures d'urgence mises en place à l'échelle nationale, mais aussi régionale, celle du Conseil de Coopération du Golfe, sont les facteurs essentiels de la réduction ou au contraire de l'accentuation de l'impact des catastrophes dans le territoire étudié. / Disasters are produced by a vigorous mankind interaction with nature. Social and economic development are major contributors to increasing disasters' vulnerability, Regardless of its various motivators, human beings have sought methods to minimize its devastating effects. Therefore, studying risks associated to natural and non-natural disasters provides means that could be utilized in the forecasting and management of risks on both natural and non-natural sides. This research aims to analyze how disaster risk management process has been built in the emirate of Abu Dhabi, United Arab Emirate, by the different stakeholders in charge whether on public or private actors. The UAE vulnerability to disasters is increasing with the huge development industrial activities taking place at the present. Furthermore, tectonic and weather related disasters are becoming very common in the UAE. Different types of disasters affect the UAE population and stretch the government and inter- agency resources as they all respond to the emergencies. The study came across many conclusions in regards to UAE continuous system of risk assessment and risk management. Many recommendations are listed for further investigation and implementation
Finally, the national and regional emergency procedures are key factors to mitigate or increase disasters' impact on regions

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