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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.
121

Numerical Simulation of Three-Dimensional Tsunami Generation by Subaerial Landslides

Kim, Gyeongbo 1978- 14 March 2013 (has links)
Tsunamis are one of the most catastrophic natural events impacting coastal regions often generated by undersea earthquakes. Nevertheless, in enclosed basins, i.e., fjords, reservoirs and lakes, subaerial or submarine landslides can initiate devastating tsunamis with similar consequences. Although a subaerial or submarine landslide that impinges into a large water body can generate a tsunami, subaerial landslides are much more efficient tsunami generators than its counterpart. In this study we aim to integrate laboratory scale experiments of tsunami generation by subaerial landslide with numerical models. The work focuses on the numerical validation of two three-dimensional Navier-Stokes (3D-NS) models, FLOW-3D and our developed model TSUNAMI3D. The models are validated based on previous large scale laboratory experiments performed by a tsunami research team lead by Dr. Hermann Fritz, Georgia Institute of Technology. Three large scale landslide scenarios were selected from the set of laboratory experiments, namely, fjord like, headland and far field coastline. These scenarios showed that complex wave fields can be generated by subaerial landslides. The correct definition and evolution of the wave field are key to accurate modeling the ensuing tsunami and its effect in coastal regions. In this study, comparisons are performed between numerical results and laboratory experiments. Methodology and key parameters for soil rheology are defined for model validations. Results of the models are expected to be under the allowable errors indicated by the National Tsunami Hazard Mitigation Program (NTHMP), National Oceanic and Atmospheric Administration (NOAA) guidelines for validation of tsunami numerical models. The ultimate goal of this research is to obtain better tsunami calculation tools for real-world application of 3-D models for landslide tsunamis, which are necessary for the construction of inundation maps in the Gulf of Mexico and the Caribbean regions.
122

Evaluation du risque tsunamique sur le littoral atlantique marocain / Evaluation tsunami risk

Mellas, Samira 03 December 2012 (has links)
Ce travail a pour objectif d’évaluer le risque de tsunami sur le littoral atlantique marocain au moyen d’une approche intégrée, menée sur la base de scénarios de risque, multiscalaires, combinant de la modélisation numérique de l’alea, une évaluation spatiotemporelle des enjeux, et des critères de vulnérabilité physique et humaine. L’étude s’articule en deux phases. Une première phase consiste à évaluer à l’échelle régionale, l’exposition du littoral atlantique marocain au risque de tsunami, en développant une démarche méthodologique de mesure de l’exposition au risque de tsunami basée sur une cartographie intégrant des paramètres d’aléa issus de la modélisation numérique d’un tsunami similaire à celui de 1755 et des bases de données régionales sur l’occupation du sol. Elle aboutit à un jeu de géo-indicateurs de risques agrégés sur plusieurs mailles territoriales (communale et mailles de 5 km de côté) qui permet de dresser une analyse comparative de ce risque à l’échelle du Maroc. Une seconde phase porte sur le risque de pertes humaines en cas de tsunami majeur sur la ville d’El Jadida, exprimé au moyen de géo-indices de risque. La vulnérabilité humaine y est exprimée par une probabilité de décès. Ces probabilités sont données par des matrices fondées sur les données de la submersion marine issues de la modélisation numérique et des critères de vulnérabilité déterminés au moyen de courbes d’endommagement empiriques. Les indices de risque obtenus intègrent la variabilité spatio-temporelle de la répartition de la population au pas horaire pour deux saisons. [etc.] / This work aim to assess the risk of tsunami along the Moroccan Atlantic coast. The approach is based on the risk scenario which combines the hazard numerical modelling, spatio-temporal, stakes and criteria of the physical and human vulnerability. This study consists firstly in assessing the exposure of the Moroccan Atlantic coast to tsunami risk at the regional scale. The approach based on coupling the numerical modeling of hazard of tsunami similar to 1755 and regional land use database. It provide a set of geo-risk indicators aggregated in several meshes on the ground (municipal grid square with side of 5km), make possible to draw a comparative analysis of the risk across Morocco. Secondly it involves the risk of loss of life in case of major tsunami at the city of El Jadida, expressed in terms of geo-risk indices. Human vulnerability is expressed by a probability of loss of life. These probabilities are given by matrices based on data from marine submersion numerical modeling and vulnerability criteria determined through empirical curves damage. Risk indices obtained include the spatio-temporal distribution of the population, in the hourly step for two seasons. [etc.]
123

Analyse probabiliste et multi-données de la source de grands séismes / Probabilistic and multi data analysis of large earthquakes source physics

Bletery, Quentin 27 November 2015 (has links)
Les séismes sont le résultat de glissements rapides le long de failles actives chargées en contraintes par le mouvement des plaques tectoniques. Il est aujourd'hui établi, au moins pour les grands séismes, que la distribution de ce glissement rapide le long des failles pendant les séismes est hétérogène. Imager la complexité de ces distributions de glissement constitue un enjeu majeur de la sismologie en raison des implications potentielles dans la compréhension de la genèse des séismes et la possibilité associée de mieux anticiper le risque sismique et les tsunamis. Pour améliorer l'imagerie de ces distributions de glissement co-sismique, trois axes peuvent être suivis: augmenter les contraintes sur les modèles en incluant plus d'observations dans les inversions, améliorer la modélisation physique du problème direct et progresser dans le formalisme de résolution du problème inverse. Dans ce travail de thèse, nous explorons ces trois axes à travers l'étude de deux séismes majeurs: les séisme de Tohoku-Oki (Mw 9.0) et de Sumatra-Andaman (Mw 9.1-9.3) survenus en 2011 et 2004, respectivement. / Earthquakes are the results of rapid slip on active faults loaded in stress by the tectonic plates motion. It is now establish - at least for large earthquakes - that the distribution of this rapid slip along the rupturing faults is heterogeneous. Imaging the complexity of such slip distributions is one the main challenges in seismology because of the potential implications on understanding earthquake genesis and the associated possibility to better anticipate devastating shaking and tsunami. To improve the imaging of such co-seismic slip distributions, three axes may be followed: increase the constraints on the source models by including more observations into the inversions, improve the physical modeling of the forward problem and improve the formalism to solve the inverse problem. In this PhD thesis, we explore these three axes by studying two recent major earthquakes: the Tohoku-Oki (Mw 9.0) and Sumatra-Andaman (Mw 9.1-9.3) earthquakes, which occured in 2011 and 2004 respectively.
124

Tsunami disaster response: A case analysis of the information society in Thailand.

Aswalap, Supaluk Joy 12 1900 (has links)
The December 2004 Indian Ocean Tsunami wrecked thousands of lives, homes, and livelihoods - losses that could have been avoided with timely and better information. A resource such as information is needed at a fundamental level much like water, food, medicine, or shelter. This dissertation examines the development of the Thai information society, in terms of the share of information workforce and the level of diffusion of information and communication technologies (ICT), as well as, the role of the Thai information society in response to the tsunami disaster. The study combined the historical and political economy analyses in explaining factors influencing the growth of information workforce and the development of ICT in Thailand. Interviews conducted in 2007-08 revealed the Thai information society responded to the 2004 Tsunami - the first global internet-mediated natural disaster - in two areas: on-site assistance in collecting and recording identification information of tsunami disaster victims and on-line dissemination of disaster relief information. The effectiveness of ICT institutions in providing the tsunami disaster relief efforts and increasing the development of the information society were assessed using statistical procedures analyzing the perceptions of the Internet-based survey respondents. The disaster effects on survey respondents were also assessed. The study's findings include: (1) the Thai information sector development pattern confirmed a key difference between development patterns of information sectors in developed and developing countries, (2) the increasing number of Thai information workers was due more to the expansion of government than the expansion in the manufacturing and service sectors during the 1997-98 Asian financial crisis, (3) Thailand's expansion of ICT infrastructure was influenced not only on the basis of economic profitability but also by political desirability, and (4) volunteers were crucial in humanitarian aid and disaster relief.
125

Impacts géomorphiques de l'éruption du Samalas en 1257 le long du détroit d'Alas, Nusa Tenggara Ouest, Indonésie / Geomorphic impacts of the 1257 CE eruption of Samalas along the Alas strait, West Nusa Tenggara, Indonesia

Mutaqin, Bachtiar Wahyu 11 December 2018 (has links)
En tant qu'événement parmi les plus puissants de l'histoire éruptive récente de Lombok, les matériaux volcaniques expulsés par le volcan Samalas en 1257 couvrent toute l'île de Lombok et sont largement répandus dans sa partie est. Près de 800 ans après l'éruption, l'impact géomorphologique de cette éruption sur l'île reste inconnu, alors que ses conséquences climatiques et sociétales globales sont désomais mieux comprises. Une combinaison des informations stratigraphiques, des topographies actuelles, des mesures géophysiques, des sources écrites locales, analyse de laboratoire et informatique ont été utilisées pour obtenir des informations détaillées sur les impacts géomorphologiques de l'éruption du volcan Samalas sur la zone côtière le long du détroit d' Alas, Nusa Tenggara Ouest, Indonésie. Cette étude fournit de nouvelles informations relatives à l'impact géomorphologique d'une éruption volcanique majeure dans des zones côtières, dans ce cas-ci, dans la partie est de Lombok, ainsi que sur la côte ouest de Sumbawa. En premier lieu, les résultats de l'étude montrent que le paysage de la partie est de Lombok est encore évolué jusqu'à présent. Le volume de matière volcanique de l'éruption des Samalas reste à environ 14% du volume initial. Deuxièmement, la découverte de Babad Suwung fournit une description supplémentaire de l'éruption des Samalas sur l'île de Sumbawa et pourraient être la plus ancienne observation visuelle de déferlantes pyroclastiques après celles de Pline Ie Jeune en 79 pour le Vésuve. Enfin, l'éruption du volcan Samalas en 1257 a prouvé avoir déclenché un tsunami mineur qui a frappé l'île de Belang, sur la côte ouest de Sumbawa. / As the most powerful event in Lombok’s recent eruptive history, volcanic materials thatwere expelled by the Samalas volcano in 1257 CE covered the entire of Lombok Islandand are widespread in its eastern part. Almost 800 years after the eruption, the geomorphological impact of this eruption on the island of Lombok remains unknown,whereas its overall climatic and societal consequences are now better understood. Acombination of stratigraphic information, present-day topography, geophysical measurement with two-dimensional resistivity profiling technique, local written sources,as well as laboratory and computational analysis, were used to obtain detailed information concerning geomorphic impacts of the 1257 CE eruption of Samalas volcano on the coastal area along the Alas Strait in West Nusa Tenggara Province, Indonesia. This study provides new information related to the geomorphic impact of amajor eruption volcanic in coastal areas, in this case, on the eastern part of Lombok and the western coast of Sumbawa. In the first place, the study result shows that since the 1257 CE eruption, the landscape on the eastern part of Lombok is still evolved untilthe present time. The volume of the 1257 CE volcanic material remains about 14% from the initial volume. Secondly, the discovery of Babad Suwung provides additional explanation of Samalas eruption and may become the oldest visual observation of pyroclastic surges and volcanic fallout, following those by Pliny the Younger in 79 CE. Finally, the 1257 CE eruption of Samalas volcano has proven triggered a minor tsunami that hit Belang Island, on the west coast of Sumbawa.
126

Modelling of tsunami generated by the motion of a rigid block along a horizontal boundary

Whittaker, Colin Nicholas January 2014 (has links)
Tsunami are a very dangerous natural hazard, as highlighted in recent years by the Indian Ocean Tsunami of 2004 and the Japan Tsunami of 2011. In the last decade, tsunami have claimed hundreds of thousands of lives, and caused billions of dollars in damage around the world. The hazard posed to coastal communities by tsunami is expected to increase in the future, due to population growth, intensification of coastal development and sea level rise due to climate change. Tsunami may be generated by a number of different source mechanisms. One such source mechanism is a submarine landslide, which can occur in a number of marine environments containing significant sediment accumulation on a sloping seafloor. The high amplitudes and rapid celerities of landslide-generated tsunami make them very dangerous to communities in the vicinity of the landslide, although these waves do not possess the potential for transoceanic devastation. The objectives of this research project are to carry out a series of two-dimensional physical experiments investigating the waves generated by a rigid block landslide moving along a horizontal boundary. The use of a horizontal boundary has the advantage that waves propagating in the offshore and onshore directions may be measured (unlike previous studies using sloping boundaries). The landslide motion is provided by a mechanical system, allowing testing of a broad range of motion, and isolation of the wavemaking properties of different phases of landslide motion. Experiments are carried out in a 14.66 m long flume, with width 0.25 m and working depth 0.50 m. A false floor installed in the flume provides the sliding surface for the landslide motion, and houses the mechanical system. A series of preliminary particle tracking velocimetry experiments confirm the ability of the mechanical system to achieve its velocity targets to within 5% or better, depending on the parameters of the landslide motion. Full spatial and temporal resolution of the wave field is achieved using a laser-induced fluorescence technique to identify the air-water interface to sub-pixel accuracy. The measurements obtained using laser-induced fluorescence are validated against measurements from a resistance wave gauge, with sub-millimetre agreement. In an additional experiment, the particle tracking velocimetry technique provides measurements of the subsurface velocity field. The landslide motion during all experiments consists of an initial period of constant acceleration, followed by a period of constant velocity, followed by a deceleration to rest (at the same rate as the initial acceleration). The landslide acceleration generates two dispersive packets of waves, travelling in the offshore and onshore directions. The offshore-propagating wave packet contains a leading crest and the onshore-propagating wave packet contains a leading trough, with both waves approaching the shallow water limit. A free surface depression forms above the landslide during its constant-velocity motion, and its amplitude may be predicted to within approximately 20% using standard hydraulic theory (considering a frame of reference moving with the landslide). The offshore-propagating waves passing over the landslide cause the amplitude of this depression to fluctuate over time. The deceleration of the landslide generates two additional packets of waves with the opposite polarity to the waves generated by the landslide acceleration. The full spatial and temporal resolution of the generated wave field allows the calculation of the potential energy within the wave field. Additionally, the energy (and mass) within the onshore- and offshore-propagating wave packets may be estimated by calculating these quantities within the onshore and offshore regions of the experimental domain. The wave packets generated by the initial landslide acceleration transport positive mass in the offshore direction, and negative mass in the onshore direction. This mass transport is balanced by the waves generated during the deceleration of the landslide. The nondimensional landslide acceleration, landslide Froude number and submergence depth are varied during the physical experiments. The landslide Froude number has the greatest effect on the behaviour of the generated wave field. At low Froude numbers, the wave field is dominated by the waves generated by the acceleration and deceleration of the landslide. As the Froude number increases, the onshore-propagating waves become negligible in amplitude compared to the offshore-propagating waves. Additionally, the free surface depression increases in amplitude and a group of short-wavelength waves become trapped behind the landslide. These waves exhibit highly nonlinear behaviour at landslide Froude numbers greater than 0.5. The simple experimental geometry allows comparison between the measured wave fields with the predictions of three mathematical models. Two inviscid-irrotational models, differing in their treatment of the bottom boundary condition, provide comparisons over the entire parameter space. These models under-predict the amplitudes of the generated waves, and fail to correctly predict the ongoing interaction between the landslide and the offshore-propagating waves. The inclusion of bottom boundary nonlinearity improves the predictions of the amplitude of the leading waves, and the potential energy within the wave field. However, both of the inviscid models do not predict the extent of wave trapping behaviour behind the landslide observed in the experiments. A viscous model, formulated in the DNS solver Gerris, improves the predictions of wave trapping (and amplitude in general) in one experiment. Although the model still under-predicts the amplitudes of the generated waves, it correctly predicts the amplification of the waves behind the landslide during its constant-velocity motion. The failure of the inviscid models to predict the amplitudes of these waves can be mostly attributed to the linearised free surface condition used by both models. The presence of the turbulent wake may also have a secondary effect on these predictions. An extension of the linear inviscid-irrotational model to three dimensions allows the effect of the landslide width on the amplitudes of the generated waves to be determined. As the width increases, the behaviour of the waves approaches the two-dimensional limiting case.
127

Numerical Modeling of Tsunami-induced Hydrodynamic Forces on Free-standing Structures Using the SPH Method

St-Germain, Philippe 23 November 2012 (has links)
Tsunamis are among the most terrifying and complex physical phenomena potentially affecting almost all coastal regions of the Earth. Tsunami waves propagate in the ocean over thousands of kilometres away from their generating source at considerable speeds. Among several other tsunamis that occurred during the past decade, the 2004 Indian Ocean Tsunami and the 2011 Tohoku Tsunami in Japan, considered to be the deadliest and costliest natural disasters in the history of mankind, respectively, have hit wide stretches of densely populated coastal areas. During these major events, severe destruction of inland structures resulted from the action of extreme hydrodynamic forces induced by tsunami flooding. Subsequent field surveys in which researchers from the University of Ottawa participated ultimately revealed that, in contrast to seismic forces, such hydrodynamic forces are not taken into proper consideration when designing buildings for tsunami prone areas. In view of these limitations, a novel interdisciplinary hydraulic-structural engineering research program was initiated at the University of Ottawa, in cooperation with the Canadian Hydraulic Centre of the National Research Council, to help develop guidelines for the sound design of nearshore structures located in such areas. The present study aims to simulate the physical laboratory experiments performed within the aforementioned research program using a single-phase three-dimensional weakly compressible Smoothed Particle Hydrodynamics (SPH) numerical model. These experiments consist in the violent impact of rapidly advancing tsunami-like hydraulic bores with individual slender structural elements. Such bores are emulated based on the classic dam-break problem. The quantitatively compared measurements include the time-history of the net base horizontal force and of the pressure distribution acting on columns of square and circular cross-sections, as well as flow characteristics such as bore-front velocity and water surface elevation. Good agreement was obtained. Results show that the magnitude and duration of the impulsive force at initial bore impact depend on the degree of entrapped air in the bore-front. The latter was found to increase considerably if the bed of the experimental flume is covered with a thin water layer of even just a few millimetres. In order to avoid large fluctuations in the pressure field and to obtain accurate simulations of the hydrodynamic forces, a Riemann solver-based formulation of the SPH method is utilized. However, this formulation induces excessive numerical diffusion, as sudden and large water surface deformations, such as splashing at initial bore impact, are less accurately reproduced. To investigate this particular issue, the small-scale physical experiment of Kleefsman et al. (2005) is also considered and modeled. Lastly, taking full advantage of the validated numerical model to better understand the underlying flow dynamics, the influence of the experimental test geometry and of the bed condition (i.e. dry vs. wet) is investigated. Numerical results show that when a bore propagates over a wet bed, its front is both deeper and steeper and it also has a lower velocity compared to when it propagates over a dry bed. These differences significantly affect the pressure distributions and resulting hydrodynamic forces acting on impacted structures.
128

Tsunami amplification phenomena / Phénomènes d'amplification des tsunamis

Stefanakis, Themistoklis 30 September 2013 (has links)
Cette thèse est divisée en quatre parties. Dans la première, je vais présenter notre travail sur le run-up des vagues longues et sur les phénomènes d’amplification par résonance. Grâce à des simulations numériques basées sur les équations en eau peu profonde non-linéaires, nous montrons que dans le cas des vagues monochromatiques d’incidence normale sur une plage inclinée, une amplification résonante du run-up se produit lorsque la longueur de la vague d’entrée est 5.2 fois plus grande que la longueur de la plage. Nous montrons également que cette amplification résonante de run-up peut être observée à partir de plusieurs profils de vagues. Cependant, l’amplification résonante du run-up n’est pas limitée aux plages inclinées infinies. En faisant varier le profil bathymétrique, la résonance est également présente dans le cas de bathymétries linéaires par morceaux et pour des bathymétries réalistes. Dans la deuxième partie, je présente une nouvelle solution analytique pour étudier la propagation des tsunamis générés par une source non ponctuelle sur une profondeur constante en utilisant la théorie des vagues en eau peu profonde linéaires. La solution, qui repose sur la séparation des variables et sur une double transformée de Fourier dans l’espace, est exacte, facile à mettre en œuvre et permet l’étude d’ondes de formes réalistes comme les ondes en forme de N (N–waves). Dans la troisième partie, j'étudie l’effet de protubérances localisées sur la génération de vagues longues. Même lorsque le déplacement final est connu grâce à l’analyse sismique, le plancher océanique qui se déforme peut avoir du relief comme des montagnes et des failles. On étudie analytiquement l’effet de la bathymétrie sur la génération des vagues de surface, en résolvant les équations en eau peu profonde linéaires avec for. Nous constatons que quand la hauteur du rebord augmente, le piégeage partiel de la vague permet de réduire la hauteur des vagues dans le champ lointain, tout en l’amplifiant au-dessus du rebord. Je vais aussi présenter brièvement une solution de la même équation forcée au-dessus d’un cône. Enfin, dans la dernière partie, nous verrons si les petites îles peuvent protéger les côtes proches de tsunamis comme il est largement admis par les communautés locales. Des découvertes récentes sur le tsunami des îles Mentawai en 2010 montrent un run-up amplifié sur les zones côtières derrière de petites îles, par rapport au run-up sur les lieux adjacents, qui ne sont pas influencés par la présence des îles. Nous allons étudier les conditions de cette amplification du run-up en résolvant numériquement les équations en eau peu profonde non-linaires. Le dispositif expérimental est régi par cinq paramètres physiques. L’objectif est double: Trouver l’amplification maximale du run-up avec un nombre minimum de simulations. Nous présentons un plan d’expériences actif, récemment mis au point et basé sur les processus Gaussiens, qui réduit considérablement le coût de calcul. Après exécution de deux cents simulations, nous constatons que dans aucun des cas considérés l’île n’offre une protection à la zone côtière derrière elle. Au contraire, nous avons mesuré une amplification du run-up sur la plage derrière elle par rapport à une position latérale sur la plage non directement affectée par la présence de l’île. Cette amplification a atteint un facteur maximal de 1.7. Ainsi, les petites îles à proximité du territoire continental agissent comme des amplificateurs des vagues longues dans la région directement derrière elles et non comme des obstacles naturels comme il était communément admis jusqu’ici. / This thesis is divided in four parts. In the first one I will present our work on long wave run-up and some resonant amplification phenomena. With the use of numerical simulations for the nonlinear shallow water equations, we show that in the case of monochromatic waves normally incident on a plane beach, resonant run-up amplification occurs when the incoming wavelength is 5.2 times larger the beach length. We also show that this resonant run-up amplification can be observed for several wave profiles such as bichromatic, polychromatic and cnoidal. However, resonant run-up amplification is not restricted to infinitely sloping beaches. We varied the bathymetric profile, and we saw that resonance is present in the case of piecewise linear and real bathymetries. In the second part I will present a new analytical solution to study the propagation of tsunamis from a finite strip source over constant depth using linear shallow-water wave theory. The solution, which is based on separation of variables and a double Fourier transform in space, is exact, easy to implement and allows the study of realistic waveforms such as N-waves. In the third part I will explore the effect of localized bathymetric features on long wave generation. Even when the final displacement is known from seismic analysis, the deforming seafloor includes relief features such as mounts and trenches. We investigate analytically the effect of bathymetry on the surface wave generation, by solving the forced linear shallow water equation. Our model for bathymetry consists of a cylindrical sill on a flat bottom, to help understand the effect of seamounts on tsunami generation. We derive the same solution by applying both the Laplace and the Fourier transforms in time. We find that as the sill height increases, partial wave trapping reduces the wave height in the far field, while amplifying it above the sill. Finally, in the last part I will try to explore whether small islands can protect nearby coasts from tsunamis as it is widely believed by local communities. Recent findings for the 2010 Mentawai Islands tsunami show amplified run-up on coastal areas behind small islands, compared with the run-up on adjacent locations, not influenced by the presence of the islands. We will investigate the conditions for this run-up amplification by numerically solving the nonlinear shallow water equations. Our bathymetric setup consists of a conical island sitting on a flat bed in front of a plane beach and we send normally incident single waves. The experimental setup is governed by five physical parameters. The objective is twofold: Find the maximum run-up amplification with the least number of simulations. Given that our input space is five-dimensional and a normal grid approach would be prohibitively computationally expensive, we present a recently developed active experimental design strategy, based on Gaussian Processes, which significantly reduces the computational cost. After running two hundred simulations, we find that in none of the cases considered the island did offer protection to the coastal area behind it. On the contrary, we have measured run-up amplification on the beach behind it compared to a lateral location on the beach, not directly affected by the presence of the island, which reached a maximum factor of 1.7. Thus, small islands in the vicinity of the mainland will act as amplifiers of long wave severity at the region directly behind them and not as natural barriers as it was commonly believed so far.
129

A systematic review of health problemsfollowing tsunamis

Toufani, Tina January 2019 (has links)
Asystematic review of health problems following tsunamis Introduction: Tsunamis are sudden onset disasters with substantial impact on human health. Toidentify the relationship between tsunamis and health problems, the evidence must besystematically reviewed. Through this, health care response can be planned accordingly. Aim: To identify the health problems following tsunamis in order to guide medical response.Methods and materials: Four databases (Medline, Global Health, Web of Science CoreCollection and Embase) were searched using an inclusive search strategy in September 2018.The inclusion criteria were published, peer-reviewed articles on morbidity with data frommedical health facilities following tsunamis, where a control or comparison group was used toanalyze the tsunami outcome. Studies on mental health problems were excluded. The studieswere analyzed through narrative synthesis. Results: Eleven articles were included in the review. There was an increase in non-traumaticconditions reported in the immediate aftermath of tsunamis. Long-term health problems on thetsunami-affected population were seen up to three years after a tsunami. There is a lack of highqualityarticles on health problems after tsunamis. Conclusions: Medical response should prepare for trauma and non-trauma care shortly after atsunami and expect an increase in certain health problems several years post-tsunami. Existing,high-quality research is limited, and this review could not capture all tsunami-related healthproblems. Future studies that identify available evidence on health care needs after tsunamisshould consider using scoping reviews to cover a broader base of literature.
130

Churning the water after the wave: water components of housing reconstruction in post-tsunami south India

Juran, Luke Robert 01 December 2012 (has links)
This dissertation provides an authoritative account of reconstruction in the water sector after the 2004 Indian Ocean tsunami in coastal, deltaic South India. In particular, this study examines 14 newly constructed housing settlements in the adjacent study areas of Nagapattinam District, Tamil Nadu, and Karaikal District, Puducherry. There is currently a paucity of literature dedicated to water components of reconstruction. Thus, this study expands the discourse and posits water elements of post-disaster processes as unique and therefore deserving of increased scholarly attention. The study is informed by a multi-methods approach and a geographical perspective. The methodologies include, inter alia, qualitative and quantitative survey instruments; key informant interviews; focus group discussions; the employment of primary documents; and environmental analyses through bacteriological and chemical water quality testing. Geographically, data, information, and actions are perceived as the coalescence of localized socio-cultural, politico-economic, and environmental fabrics. This approach to viewing circumstances is imperative for dissecting the outcomes of reconstruction processes in a specific context, and consequently for understanding problems, identifying solutions, and gauging the appropriateness of particular configurations in place-based systems. This dissertation critiques the models utilized for reconstruction in the two study areas. The scales of inquiry are demographically and geo-physically similar, yet differ in political organization. It is argued that Nagapattinam executed a model of reconstruction founded on collaborative governance, while Karaikal exercised a single agency approach. Thus, various governmental agencies were responsible for specific reconstruction activities in Nagapattinam, whereas a single agency was responsible for all activities in Karaikal. In general, the latter approach, which was less layered, produced comparatively better outcomes. Moreover, both jurisdictions implemented 'hard' paths for water management and operationalized panoptic and revenue-based methods of reconstruction, albeit inefficiently. Numerous shortcomings in reconstruction outcomes were uncovered (e.g., water quality, quantity, and pressure), as were an array of organic coping mechanisms established by affectees in order to surmount such inadequacies. To that end, it is contended that: the coping mechanisms fail to remedy the condition; much of the waterscape is beyond the control of the subjects; and the governments are ultimately deficient in responding to the needs of their citizens. The post-tsunami waterscapes are also analyzed quantitatively through the development of a contextualized, multi-scalar Water Poverty Index (WPI). The WPI is deployed with three distinct weighing schemes and reveals that, on the whole, the sites situated in Karaikal generally perform better than those in Nagapattinam. Interestingly enough, the sites located in rural Nagapattinam outperform their urban counterparts. This case--primarily a product of different water treatment processes--challenges conventional rural-urban dichotomies. Given the occurrence of poor water quality, an investigation of boiling as a method of household water treatment (HWT) surfaces several barriers to and caveats of its adoption. Data indicate that boiling is less effective than could be; thus, it is argued that boiling may not be the optimal strategy for HWT. Lastly, advised by the corpus of data, this dissertation presents a novel framework for managing water components of post-disaster reconstruction. The framework identifies common project failures, can be harnessed independently or alongside existing instruments, and possesses diagnostic, management, and evaluative potential.

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