Dissertations / Theses: 'Coastal event'

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Shah-Hosseini, Majid. "Geomorphic evolution and coastal hazards along the Iranian coast of Makran." Thesis, Aix-Marseille, 2014. http://www.theses.fr/2014AIXM3010.

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Cette thèse a deux objectifs principaux: (i) la reconstruction de l'évolution des plaines côtières autour des baies de Chabahar et de Pozm et (ii) L'évaluation des risques côtiers (tsunamis et tempêtes extrêmes) par l'étude des dépôts de haute énergie. Vastes plaines côtières et paleo-rivages protégées par des terrasses marines soulevées sont présents autour des baies de Chabahar et Pozm. Nous avons mise en évidence des changements du niveau marin relatif le long de quatre profils. L'architecture interne des paleo-rivages a été imagée en utilisant le géoradar (GPR). Des analyses sédimentologiques et stratigraphiques des séquences côtières ont été examinées par carottages et tranchées. Les paleo-rivages sont datées entre 4800 et 270 ans BP à des distances respectives de 5 km et de 670 m du rivage actuel. La position spatiale des paléo-rivages montre une chute du niveau relatif de la mer de 15 m au cours des 4800 derniers années. Nous insistons aussi sur le rôle de contrôle des structures géologiques. Les dépôts d'événements (tsunami et tempêtes) ont été étudiés en contexte de côte meuble par Les sédiments sableux et coquilliers d'origine marine, et sur les côtes rocheuses par les dépôt des blocs déplacés. Nous avons appliqué des modèles hydrologiques pour évaluer et comparer la hauteur des vagues et la distance d'inondation. Nos résultats montrent qu'aucun événement de tempête, connu ou potentiel, n'est capable de transporter les blocs observés. Des vagues de tsunamis de l'ordre de 4 m de hauteur sont suffisantes pour transporter les blocs. La côte de Makran a enregistré des indices de paléo-tsunamis probablement générés par de grands séismes dans la zone de subduction
In this thesis we have two main goals: (i) to reconstruct the Holocene coastal evolution and relative sea-level changes using strandplains around the Chabahar and Pozm bays; and (ii) to evaluate coastal hazards (tsunami and extreme storms) along the Iranian coast of Makran using high-energy deposits. Since the mid-Holocene, the shoreline rimming the bays of Chabahar and Pozm has prograded ~5 km and formed extensive strandplains. We documented relative sea-level changes along four coast-normal profiles. Internal architecture of strandplain imaged using Ground Penetrating Radar (GPR). The sedimentology and stratigraphy of the coastal sequence were studied by coring and trenching. The highest paleo-coastline is located about 5 km inland and stands approximately 15 m above present sea level. Paleo-shorelines date back between 4800 and 270 years BP at respective distances of 5 km to 670 m from the active shoreline. The spatial position of the palaeo-coastlines demonstrates a fall in local sea level of around 15 m during the last ~4800 years. Event deposits attesting to high-energy waves have been studied in low-lying coast by study of Over-washed sandy and shelly marine sediment and on the rocky shore by study of displaced boulder deposits. We applied hydrologic models to estimate the height and inundation distance of exceptional waves. Our results demonstrate that no known or probable storm is capable of detaching and transporting the boulders. Tsunami waves 4 m in height are enough to transport the boulders. We conclude the Makran coast has archived evidence of palaeo-tsunami events generated in the Makran subduction zone

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Narwich, Charles Bryan. "Event Stratigraphy Based on Geochemical Anomalies within a Mixed-Sediment Backbarrier Sequence, Southern New Jersey." Master's thesis, Temple University Libraries, 2012. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/194335.

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Geology
M.S.
Detection of large-magnitude coastal events, especially in wave-dominated retrograding barrier settings, has traditionally relied upon lithological evidence, such as distinct overwash sand layers within the muddy backbarrier sequences. In tide-dominated environments, unconformities in marsh stratigraphy have been interpreted as rapid drowning or erosion events caused by large storms. In transitional mixed-energy backbarrier environments, however, clearly identifiable event horizons are rare, due to unfavorable conditions for peat formation or to a lack of overwash. To address these challenges, the present study utilized X-ray fluorescence (XRF), magnetic susceptibility (MS), and X-ray diffraction (XRD) techniques to identify anomalies within 4-to-7-m-thick sequences recovered from Sewell Point, Cape May, New Jersey. In these cores, at least five peaks were identified that exhibit up to three-to-four-fold increase in Fe (up to 6.2%) and Ti (up to 0.5%) concentrations and a substantial increase in MS values (> 200 μSI). The sand fraction at these intervals exceeds 40% and is represented by moderately well-sorted, negatively-skewed, fine-grained sand (2.7 φ). Fe, Ti, and MS are positively cross correlated due to the relatively high content of sand-sized heavy minerals such as magnetite, rutile, ilmenite and biotite, as well as phlogopite and muscovite mica. These minerals were also identified using a Rigaku Dmax/B X-ray diffraction device. Seven radiocarbon-dated in situ samples of intertidal gastropods and the few available rhizomes indicate that the Sewell Point sequence accumulated over the past 900-1,000 years, at an average sedimentation rate greater than 4.5 mm/yr, which is consistent with its proximity to a historically active tidal inlet. Lithological anomalies at Sewell Point are interpreted as the signatures of episodic large-magnitude sediment fluxes into the paleo-lagoon. The calibrated ages of organic remains (mollusks and rhizomes) constrain chronology and allow interpretation of these stratigraphic layers as event horizons with historical storms of 1594, 1743 and 1821, along with pre-historic storms in the 11th-13th centuries. This research indicates that geochemically diagnostic intervals offer an effective tool for detection of event horizons and their regional correlation in mixed-sediment backbarrier settings.
Temple University--Theses

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Larson, Rebekka Amie. "High-Resolution Event Stratigraphy of mm-Scale Laminated Sediments from Coastal Salt Ponds: St. John, US Virgin Islands." Scholar Commons, 2011. http://scholarcommons.usf.edu/etd/3196.

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A multi-proxy approach is utilized on mm- to cm-scale laminated sediment records in coastal salt ponds on St. John, U.S. Virgin Islands to characterize the sediments, identify their sources and depositional processes/events (heavy rainfall, tropical cyclones, tsunamis). Historical records are combined with high-resolution geochronology (short-lived radioisotopes, 210Pb, 137Cs, 7Be) and scanning elemental techniques (XRF and LA-ICP-MS) to link depositional events to how they are manifested in the sedimentary record. Volcanic rocks are the terrigenous sediment source and the sedimentary signature of terrigenous sediment in the geologic record consists of higher amounts of Al, Fe, Ti, Co, and Si, and is associated with terrigenous runoff due to rainfall events. A minimum threshold value of >2.0 mm per day (minimum to erode and transport terrigenous sediment downslope) of rainfall has been determined for the study area. The frequency of heavy rainfall events that exceed the threshold of >2.0 mm per day is significantly correlated to the amount of terrigenous sediment accumulation of the terrigenous indictor element Al measured by scanning LA-ICP-MS. There is a robust sedimentary record of terrigenous sediment runoff that is a function of the frequency of heavy rainfall events (exceed threshold). Variability in the sedimentary record reflects changes between periods of "wet" increased frequency of heavy rainfall events and "dry" decreased frequency of heavy rainfall events. Tropical cyclones and tsunamis can cause marine overwash into salt ponds leading to deposition of marine sediments. Elemental scans for Ca and Sr and overwash indicator elements are complicated by grain size effects of LA-ICP-MS techniques, as well the difficulty in differentiating between tropical cyclone overwash deposits and tsunami deposits. By defining the sedimentary signature for depositional events , geologic records can be interpreted to provide insight into the natural variability of these processes throughout geologic time for comparisons to the more recent anthropogenic time period. This study provides a framework that can be applied to other coastal environments on high-relief tropical islands, to compare local records, and provide information on regional processes controlling rainfall variability in tropical latitudes.

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Alexander, Shavonne A., Walter R. Brinkley, Jordan M. Cohen, Thomas M. Roberts, Paul Beery, Joseph Bubulka, Matt C. Kenfield, and Johnny M. Quilenderino. "Influence of foreign humanitarian assistance/disaster relief in a coastal nation." Thesis, Monterey, California. Naval Postgraduate School, 2011. http://hdl.handle.net/10945/7074.

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Further distribution of all or part of this report is subject to the Distribution Statement appearing on the front cover.
One of the global security challenges the United States faces is disaster coupled with political instability. The U.S. Military‘s ability to rapidly respond to disasters enhances regional and global security and stability. Foreign Humanitarian Assistance and Disaster Relief (FHA/DR), increasingly a mission that relies on a significant military component, focuses on the provision of goods and services such as health care, supplies necessary for survival, and infrastructure repair, with the goal of reducing the immediate human suffering. The disaster in this project‘s scenario is catastrophic flooding that occurs in one of Africa‘s most populated and wealthiest countries that threatens the stability and development of West Africa. This project, employing a systems engineering methodology, focuses on the 60 days after the disaster and the requirements to provide this assistance in the form of goods and services. Many system-of-systems architectures were developed to investigate the effectiveness of utilizing a Seabase for the primary delivery of aid. Two simulation tools, SimKit, and STELLA, were used to model and examine these architectures with the former addressing the delivery and throughput concerns while the latter focused on the satisfaction of the population and the limitation of criminal activity. Based on the results of modeling, the team provided recommendations relative to the most effective architectures in influencing the population of this coastal area as well as accomplishing the FHA/DR mission.

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Hickey, Rachel. "Evaluation of Endocrine Disrupting Chemicals in the Florida Coastal Pelagic Fish Complex Following the Deepwater Horizon Oil Spill Event." NSUWorks, 2015. http://nsuworks.nova.edu/occ_stuetd/44.

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Following the BP Deepwater Horizon oil spill event, there was a critical need to assess the effects of the oil and dispersant chemicals on the coastal pelagic fish complex in the Gulf of Mexico and the Florida Straits. The objective of this study was to determine if spilled crude oil and dispersant chemicals have posed an ecological risk to the coastal pelagic fish complex through the detection of vitellogenesis. Crude oil containing polycyclic aromatic hydrocarbons (PAHs), dispersant chemicals and other estrogen-mimicking compounds are suspected to induce vitellogenin production in male and immature female fish, normally only produced by sexually mature females. Blood plasma and surface mucus were collected from wild-caught adult and juvenile males and females from as many representative coastal pelagic species as possible (including yellowfin tuna Thunnus albacares and swordfish Xiphias gladius). To create a control for this experiment, crevalle jacks (Caranx hippos) and lookdowns (Selene vomer) were injected with estradiol-17β (10 μg/g body weight) into the peritoneal cavity to induce vitellogenesis, regardless of sex or reproductive stage. The mucus and blood plasma of each injected fish was collected 7 to 11 days post-injection. Mucus and blood plasma samples of wild-caught and experimentally-injected fishes were separated using sodium dodecyl sulphate-polyacrylamide gel electrophoresis, stained with a phosphoprotein specific fluorescent dye (Pro-Q Diamond®), and visualized through ultraviolet transillumination. Vitellogenin was visibly detectable in the mucus collected from the control-injected fish, suggesting a disruption in the endocrine system as a result of estrogen exposure (estradiol-17β). However, there were no elevated levels of vitellogenin detected in any wild-caught fish mucus or blood plasma samples, indicating no vitellogenesis. From this, we infer that there has been no detectable endocrine disruption to the sampled coastal pelagic fish complex in the Gulf of Mexico two years after the start of the spill.

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CUTRONEO, LAURA. "Use of microseismic data to monitor significant sea wave heights in support of marine weather forecasting and coastal protection." Doctoral thesis, Università degli studi di Genova, 2022. http://hdl.handle.net/11567/1076418.

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The focus of the Ph.D. project was the implementation of a network for monitoring significant sea wave heights (Hs) along the Ligurian coasts (north-western Mediterranean Sea), in order to provide near-real time data to weather forecasters and sea users (vessel captains, pilots, Coast Guard, Port Authorities and yachtsmen). The project was divided into a part dedicated to the use of microseismic data, interfaced with data derived from modelling hindcasts and from the wave buoy of Capo Mele, for the determination of Hs, and a part dedicated to the Interreg Italy-France Maritime 2014-2020 SINAPSI "Assistance to navigation for safe access to ports” Project, which involves the installation of instruments for measuring weather and sea parameters along the coasts of the Ligurian Sea. The first phase of the Ph.D. project involved the study and updating of a mathematical procedure for the estimation of Hs from the microseismic data recorded by the network of seismic stations along the Ligurian arch. The procedure exploited the existing relationship between sea wave heights and microseismic signal and included the use of hindcast data to calibration steps and data from the Capo Mele wave buoy to verify the reliability of the estimated Hs data. In October 2018, an extreme sea storm hit the Ligurian coast with waves characterised by Hs greater than 6 m; these wave heights were not matched by an equivalent energy in the microseismic signal, which therefore led to an underestimation of the Hs estimated by the procedure. It was therefore necessary to investigate the extreme event of 2018, which led to the evidence of a lack in the energy of the microseismic signal and the need for a data compensation, which was possible thanks to the use of weather data (wind speed and atmospheric pressure) that were included in an additional element to the estimation procedure. The second phase of the Ph.D. project therefore involved verifying the reliability of the data estimated by the procedure, which led to the evidence of a generic underestimation of Hs. This led to the study of a first modification of the procedure and to the consequent monitoring of its validity on a large time scale. The monitoring of the reliability of the estimated data will be continued after the end of the Ph.D., as well as the updating/refinement of the procedure. The Ph.D. project involved the participation in the SINAPSI Project, which started in April 2019, in all its components, from the management to the implementation of the monitoring network, also including the communication and dissemination of the project activities to the stakeholders. The Ph.D. has achieved the improvement of the Hs estimation procedure. The research activities will continue beyond the Ph.D. natural end to implement the results with data from a radar antenna system that will be installed in the Genoa area in the framework of the SINAPSI Project.

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Perkowski, Matthew Paul. "An analysis of the gypsy moth event monitor modified forest vegetation simulator and the stand damage model using empirical long-term measurement plot data from the Appalachian hardwood and the Atlantic Coastal Plain mixed pine-hardwood regions." Morgantown, W. Va. : [West Virginia University Libraries], 2008. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=5856.

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Thesis (M.S.)--West Virginia University, 2008.
Title from document title page. Document formatted into pages; contains ix, 103 p. : ill. (some col.), col. maps. Includes abstract. Includes bibliographical references (p. 77-79).

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Noyer, Mégane. "Développement d'indicateurs microbiens de multipollutions en Méditerranée : vers un outil d'évaluation de la qualité des eaux douces Particle-attached riverine bacteriome shifts in a pollutant-resistant and pathogenic community during a mediterranean extreme storm event Evolution of the particle-attached riverine archaeome compared to the bacteriome as a result of multipollution following a mediterranean extreme event." Thesis, Perpignan, 2020. http://www.theses.fr/2020PERP0027.

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Les écosystèmes d’eau douce sont très vulnérables face aux perturbations anthropiques. Ils peuvent en effet subir de multiples pollutions via entre autres le lessivage des sols des bassins versants mais aussi la remobilisation des sédiments des lits des rivières et des réseaux d’assainissement, phénomènes accentués lors des épisodes pluvieux, particulièrement intenses et fréquents dans les régions au climat méditerranéen. Lors d’un épisode méditerranéen étudié précédemment, il a été démontré que des déversements de mélanges de polluants se produisaient, coïncidant avec le pic de débit et du débordement des déversoirs d’orage (DDO) qui l’ont précédée. Au cours de cette thèse, nous avons pu vérifier que ces multipollutions sont récurrentes, se produisant à chaque DDO et pic de débit lors de deux autres crues. Nous avons donc émis l’hypothèse que les communautés microbiennes fluviatiles, qui constituent le seul compartiment biologique capable de dégrader les polluants, pourraient être largement impactées par ces multipollutions récurrentes en méditerranée. Cette thèse visait ainsi à déterminer l'évolution du microbiome fluviatile au cours d’événements pluvieux extrêmes, et ce, à travers la modélisation statistique combinant des données de séquençage haut débit à une large panoplie de paramètres environnementaux. Les résultats obtenus démontrent une relation significative entre les multipollutions et l’apport de microorganismes liés à la matière fécale, aux milieux urbains et résistants aux polluants et/ou pathogènes. Ces microorganismes exogènes pourraient affecter fortement les communautés résidentes. Compte tenu de la réaction rapide du microbiome fluviatile face aux multipollutions, nous avons également mis en évidence des microorganismes clés de stress multiple, qui pourraient servir comme nouveaux biomarqueurs à incorporer dans un outil de détection de multipollutions pour le suivi de la qualité des eaux
Freshwater ecosystems are highly vulnerable to anthropogenic disturbances. Indeed, they can be subject to multiple forms of pollution via, among other things, the leaching of soil from catchment basins but also the remobilisation of sediment from river beds and sewerage networks, phenomena that are accentuated during rainy episodes, which are particularly intense and frequent in regions with a Mediterranean climate. In a Mediterranean event studied previously, it was shown that discharges of pollutant mixtures occurred, coinciding with the water discharge peak and combined sewer overflows (CSO) that preceded it. During this thesis, we were able to verify that these multipollutions are recurrent, occurring at each CSO and water discharge peak along two other floods. We hypothesised that fluvial microbial communities, which constitute the only biological compartment able to degraded pollutants, could be largely impacted by these recurrent multipollutions in Mediterranean. This thesis aimed to determine the impact of pollutant mixtures on the evolution of the fluvial microbiome during extreme rainfall events via statistical modelling coupling high throughput sequencing data to a wide range of environmental parameters. Results showed a significant relationship between multipollutions events at CSOs and water discharge peak and the appearance of microorganisms linked to faecal matter, urban environments and resistant to pollutants and/or pathogens, which could strongly affect riverine resident communities. Given the rapid response of the fluvial microbiome to multi-pollutants, we were able to identify key multi-stress microorganisms, that could be used as new biomarkers to be incorporated into a multi-pollutant detection tool for water quality monitoring

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Kortekaas, Stella. "Tsunamis, storms and earthquakes : distinguishing coastal flooding events." Thesis, Coventry University, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.491429.

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Rehak, Katrin, Manfred Strecker, and Helmut Echtler. "DEM supported tectonic geomorphology : the Coastal Cordillera of the South-Central Chilean active margin ; [Poster]." Universität Potsdam, 2006. http://www.uni-potsdam.de/imaf/events/ge_work0602.html.

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Fluvial systems are one of the major features shaping a landscape. They adjust to the prevailing tectonic and climatic setting and therefore are very sensitive markers of changes in these systems. If their response to tectonic and climatic forcing is quantified and if the climatic signal is excluded, it is possible to derive a local deformation history.
Here, we investigate fluvial terraces and erosional surfaces in the southern Chilean forearc to assess a long-term geomorphic and hence tectonic evolution. Remote sensing and field studies of the Nahuelbuta Range show that the long-term deformation of the Chilean forearc is manifested by breaks in topography, sequences of differentially uplifted marine, alluvial and strath terraces as well as tectonically modified river courses and drainage basins.
We used SRTM-90-data as basic elevation information for extracting and delineating drainage networks. We calculated hypsometric curves as an indicator for basin uplift, stream-length gradient indices to identify stream segments with anomalous slopes, and longitudinal river profiles as well as DS-plots to identify knickpoints and other anomalies. In addition, we investigated topography with elevation-slope graphs, profiles, and DEMs to reveal erosional surfaces.
During the first field trip we already measured palaeoflow directions, performed pebble counting and sampled the fluvial terraces in order to apply cosmogenic nuclide dating (¹⁰Be, ²⁶Al) as well as provenance analyses.
Our preliminary analysis of the Coastal Cordillera indicates a clear segmentation between the northern and southern parts of the Nahuelbuta Range. The Lanalhue Fault, a NW-SE striking fault zone oblique to the plate boundary, defines the segment boundary. Furthermore, we find a complex drainage re-organisation including a drainage reversal and wind gap on the divide between the Tirúa and Pellahuén basins east of the town Tirúa. The coastal basins lost most of their Andean sediment supply areas that existed in Tertiary and in part during early Pleistocene time. Between the Bío-Bío and Imperial rivers no Andean river is recently capable to traverse the Coastal Cordillera, suggesting ongoing Quaternary uplift of the entire range.
From the spatial distribution of geomorphic surfaces in this region two uplift signals may be derived: (1) a long-term differential uplift process, active since the Miocene and possibly caused by underplating of subducted trench sediments, (2) a younger, local uplift affecting only the northern part of the Nahuelbuta Range that may be caused by the interaction of the forearc with the subduction of the Mocha Fracture Zone at the latitude of the Arauco peninsula. Our approach thus provides results in our attempt to decipher the characteristics of forearc development of active convergent margins using long-term geomorphic indicators. Furthermore, it is expected that our ongoing assessment will constrain repeatedly active zones of deformation.

Interdisziplinäres Zentrum für Musterdynamik und Angewandte Fernerkundung
Workshop vom 9. - 10. Februar 2006

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Stolle, Jacob. "Debris Hazard Assessment in Extreme Flooding Events." Thesis, Université d'Ottawa / University of Ottawa, 2019. http://hdl.handle.net/10393/39621.

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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.

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SOLE, FRANCESCO MARIA. "Valutazione della vulnerabilità delle coste della Sardegna a fenomeni di erosione ed inondazione dovuti all'impatto degli eventi estremi meteo-marini." Doctoral thesis, Università degli Studi di Cagliari, 2016. http://hdl.handle.net/11584/266637.

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The main goal of this work is to provide a regional assessment of the coastal vulnerability of Sardinian sandy beaches to storm impacts. To do this we have assessed the geomorphic coastal vulnerability taking into account the intensity of storm induced hazards and the adaptation capacity of the system. The methodology aplied allows to calculate quantitatively -in a separate manner- the erosion and inundation hazards induced by the storms associated to a given probability of occurrence. The practical application of this method is to provide information that allows stakeholders to manage resource allocation and mitigate consequences. This framework has been developed by covering the following steps:(i). Define forcing conditions for the Sardinian coast using a storm classification method; to obtain this we have divided the Sardinian coast in 4 different sectors. For each sector storm events have been defined from hindcast wave data obtained for the period between 1979-2012. (ii) Find out the induced beach response to each storm class measured by the quantification of the flooding and erosion hazards. In each sector sandy beaches have been characterized in terms of their slope, height, widht and grain size. (iii) Estimation of a coastal vulnerability index formulated in terms of these two intermediate variables by means of a linear function that ranges from a minimum value of 0 (optimum state) to a maximum of 1 (failure state), defining 5 qualitative categories (Very Low, Low,. Medium, High, Very High). (iv) Assessment and mapping of the coastal vulnerability index along different sectors of the island. In terms of prospective analysis we have built a projected timeline of beach hazard based on existing storm data fitted into an extreme probability function. Once the probability of occurrence of the flooding and erosion hazards has been assessed and a risk level defined by the stakeholders, the spatial distribution of vulnerabilities associated to selected probability level will permit to "robustly" compare areas along the coast to identify the most endangered zones.

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Wadey, Matthew P. "Understanding defence failures and coastal flood events : a case study approach." Thesis, University of Southampton, 2013. https://eprints.soton.ac.uk/359740/.

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Extreme sea level events are a current global threat, whilst sea-level rise (SLR) and climate change over the 21st century will increase the frequency and severity of flooding in most coastal regions. Numerical model simulations can help to understand and predict coastal floods (e.g. flood mapping and forecasting) but in comparison to flood sources (waves and water levels) coastal flood pathways (defence failures and inundation) are presently less integrated within these models. This thesis develops and demonstrates a methodology to rapidly simulate and understand the consequences of coastal flood events, with an emphasis upon regions where the risks of flooding are not well understood and could change quickly with SLR. The Solent on the south coast of England is the case study, and is prone to frequent flooding. This region is currently differentiated from the UK east and west coasts by experiencing smaller storm surges, and is characterised by undefended sections of shoreline and small floodplains. Within the Solent is Portsmouth, a city of national flood significance (only London and Hull contain more people considered at risk of coastal flooding in the UK). However, life threatening floods have not occurred in living memory. An integrated modelling approach is developed, coupling loads and defence failures with two-dimensional simulations of floodplain inundation. Observations collated from a real storm surge and flood event are shown to generate a validation data set, which indicates that this model can predict floodplain water levels to a good level of accuracy, whilst highlighting implications of such data collection. Solent-wide analysis includes simulations of hypothetical coastal flood events based upon scenarios that cover the full range of coastal loadings (realistic waves and water levels) and defence failures (overflow, outflanking, overtopping and breaching). More detailed case-studies are also applied at two sites within the region (including Portsmouth). This analysis generates peak flood water depths and an overview of impacts across this spectrum of possible floods. This research improves the existing knowledge of coastal flooding in the case study, and highlights a number of generic concepts that should be applied to others. For example the combination of flood simulation methods with real flood event analysis is essential for optimising the interpretation of model outputs whilst supporting inferences about flood consequences associated with extreme loading events (including how these may change with SLR). Simple methods estimated that >24,000 properties are within a 1 in 200 year flood event outline; and incorporating defence failures, flood dynamics, validation and detailed case studies substantially refine the assessment of places likely to experience damages. Breach defence failures generate the worst flood impacts, although in the Solent this failure mechanism is presently less of a threat than outflanking, overflow and wave overtopping. The modelling system includes easily interpreted outputs, whilst being computationally fast; therefore with potential applications including supporting land-use and defence planning, and real-time flood forecasting and warning.

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Hepworth, Daniel Ary. "Response of a Partially Mixed Coastal Plain Estuary to Storm Events." W&M ScholarWorks, 1988. https://scholarworks.wm.edu/etd/1539617584.

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Pavel, Md Tanvir. "Three Essays on Managing Extreme Weather Events and Climatic Shocks in Developing and Developed Countries." FIU Digital Commons, 2018. https://digitalcommons.fiu.edu/etd/3797.

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Climate change and extreme weather events are affecting the environment, and people’s livelihood in both developing and developed countries. Agriculture, forestry, fishing, livestock, water resources, human health, terrestrial ecosystems, biodiversity, and coastal zones are among the major sectors impacted by these shocks. The challenge of adaptation is particularly acute in the developing countries, as poverty and resource constraints limit their capacity to act. Bangladesh fits in this category, and thus I use data from Bangladesh to analyze the adaptation process in the first and second chapter of my dissertation. In the first chapter, I investigate whether transient shocks (flood, cyclone) or permanent shocks (e.g., river erosion that leads to permanent loss of lands) have more influence on interregional migration. Findings of the study suggest that the households prefer to move to the nearest city when the environmental shock is temporary, whereas they tend to relocate over a greater distance when the environmental shock is more permanent in nature. In the second chapter, I investigate the feasibility of a set of adaptation measures to cope with hydro-climatic shocks (e.g. floods, drought, cyclones, tidal waves) and epidemic shocks (emergence or re-emergence of infectious diseases on livestock and poultry) in the agricultural sector in Bangladesh. Findings suggest that a decrease in agricultural income due to climatic and/or epidemic shocks is likely to induce households to adapt more. Developed countries are also vulnerable to extreme weather events and climatic shocks. In 2017, United States was hit by three consecutive hurricanes: Harvey, Irma, and Maria. Given the rising exposure and the increasing need to manage coastal vulnerability, the third essay focusses on understanding household preferences for financing adaptation activities in the U. S. and analyzes which mechanism, i.e., state or federal adaptation fund approach, is better suited to managing exposure to such types of natural disaster in the future.

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Saeck, Emily A. "Nutrient Dynamics of Coastal Phytoplankton: The Role of Episodic Flow Events and Chronic Sewage Discharges." Thesis, Griffith University, 2012. http://hdl.handle.net/10072/367866.

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Nutrient enrichment of coastal zones can lead to longer phytoplankton bloom seasons, shifts in phytoplankton community composition and a higher frequency of harmful algal bloom events (HABs). Predicting the effect of nutrient enrichment on any given coastal system is challenging, as the response is mediated by the physical and biological characteristics of the system and the way in which nutrients are delivered to the system. For example, in tropical and sub-tropical regions, the majority of annual nutrient loads are delivered via episodic high-flow events during the wet season. These events stimulate phytoplankton growth and are known to represent an important driver of coastal productivity. However, in populated coastal settings other nutrient inputs from point sources, such as sewage treatment plants (STP), are typically delivered as a relatively constant discharge. While chronic STP nutrient loading may be relatively low compared to flow event inputs, their continuous delivery throughout the year may represent a significant source of nutrients for phytoplankton growth, particularly during the dry seasons. These different sources of nutrients, and the spatial and temporal characteristics of their delivery to receiving waters, likely influence the responses of phytoplankton communities.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Environment
Science, Environment, Engineering and Technology
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17

Trubilowicz, Joel William. "Hydrometeorology and streamflow response during rain-on-snow events in a coastal mountain region." Thesis, University of British Columbia, 2016. http://hdl.handle.net/2429/58191.

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Rain-on-snow, in which rainfall occurs upon a previously existing snowpack, complicates runoff response to rain events. In some situations the snowpack absorbs rainfall; in others, runoff is enhanced by significant snowmelt. Rain-on-snow has generated major floods around the world, particularly in coastal, mountainous regions such as southwestern British Columbia, where the rugged topography can cause rapid and varying transitions between rainfall and snowfall within the same watershed, and warm, subtropical storms known as atmospheric rivers can deliver large quantities of precipitation. This thesis sought to further the understanding of rain-on-snow at the regional scale, including its role in runoff response to a wide spectrum of rain-on-snow events. Tools were developed and assessed to help achieve this goal and for use by others. First, the hydrologic utility of output from a regional weather reanalysis model was tested. Results showed air temperature and vapour pressure were likely to be useful, whereas other variables were not accurate enough to be of use. Air temperature, in particular, showed potential ability for more accurate specification of temperature gradients for hydrologic forecasting of rain-on-snow runoff. An analysis of rain-on-snow events across five automated snow pillow sites over 10 years illustrated the importance of understanding the amount of rainfall occurring at high elevations during rain-on-snow, and the relatively consistent enhancement of water available for runoff (WAR) by 25-30% due to snowmelt during large rain-on-snow events. For smaller events, a range of antecedent and meteorological factors influenced WAR generation, particularly the antecedent liquid water content of the snowpack. A probabilistic method for infilling cloud obscured pixels in optical remotely sensed snow cover imagery showed strong performance compared to more standard methods, and illustrated spatial changes in snow cover during the largest flood event within the analysis period. This method was developed to maximize information gain from satellite snowcover imagery while minimizing the transfer of disinformation. Finally, high elevation rainfall during atmospheric river events was found to be the dominant predictor of runoff response in six study catchments in the region. Antecedent snowcover provided only minimal increases in the ability to predict runoff during these events compared to rainfall alone.
Arts, Faculty of
Geography, Department of
Graduate

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18

Sobotka, Molly. "Legacy sediments in streams - effects on nutrient partitioning during simulated re-suspension events." VCU Scholars Compass, 2011. http://scholarscompass.vcu.edu/etd/2564.

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Anthropogenic inputs of nutrients and sediment are a widespread problem in U.S. streams causing localized impairment and contributing to eutrophication of coastal habitats. Sediments and dissolved nutrients interact through diverse processes including ion exchange, sorption and biotic assimilation by particle-bound bacteria. This study examined the effects of sediment re-suspension on nutrient partitioning in lab microcosms using fine benthic matter collected from two Virginia Coastal Plain streams. Kimages Creek was recently restored following dam removal and was characterized by large deposits of legacy sediments. Courthouse Creek was characterized by sandy substrates typical of Coastal Plain streams. Sediment characteristics differed between the two sites and were influenced by discharge. Net nutrient release rates were similar between streams though reactivity of Courthouse Creek sediments was greater than that of Kimages Creek. Equilibrium Phosphate Concentrations calculated for each site show that fine sediments at Kimages Creek have resulted in higher phosphorus retention potential.

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19

Diggins, Jennifer. "Slippery fish, material words : the substance of subsistence in coastal Sierra Leone." Thesis, University of Sussex, 2014. http://sro.sussex.ac.uk/id/eprint/51443/.

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This thesis is based on eighteen months' fieldwork in Tissana: a bustling multi-ethnic fishing town on Sierra Leone's southern coast. It tells the story of the successive waves of young migrants who, for several decades, have been arriving on the coast from rural areas seeking an alternative to the indentured labour conditions of a farming economy still shaped by the legacy of domestic slavery. Set against the backdrop of a rapidly changing post‐war economy, and in an ecological context in which fish stocks are in treacherous decline, I explore the intersection between people's everyday struggles for economic survival and their taken-for-granted knowledge of the substance of the world within which those fragile livelihoods play out. In a region in which we have come to correlate ‘memory' with the collective scars of slavery and civil war, Tissana's older residents look back with nostalgia and remember the youthful energy, conspicuous consumption and seemingly easy ‘freedom' of their town's early boom years. In some respects, the pattern is familiar from accounts of resource rushes all across Africa: the convergence of large numbers of young strangers in an unfamiliar landscape far from the authority of village elders opened up a space in which a new kind of moral economy emerged. However, within just a few decades of its initial boom, the fluidity of Sierra Leone's fishing economy is already under intense pressure. Fish stocks have suffered a noticeable decline and, as catches become smaller and more erratic, people find themselves drawn once more into networks of dependency and reciprocity that offer their only viable hope of material security. A constant tension animating everyday life in Tissana is how people are able to work, through the strategic deployment of material gifts, to nurture the relationships that they rely upon for their subsistence, whilst simultaneously attempting to protect themselves from becoming entangled in other, less appealing social bonds. At its core, then, this is a work about the materiality of human relationships; of social bonds formed and lived under conditions of such stark economic uncertainty that, very often, ‘love' and ‘livelihoods' are difficult to disaggregate — and even more difficult to trust. Here relationships often have a peculiarly fleshy, ethnographically observable aspect. One can go a long way towards mapping the town's fluctuating networks of friendship, love, debt, and obligation simply by watching the gifts of fish exchanging hands on the wharf. The town also raises a quite particular set of problems for an anthropologist interested in the materiality of social life. I explore how the lived experience of poverty, and the anxiety of stretched livelihoods are entangled with quotidian discussions of blessings, swears, initiation societies, and ‘fetish' medicines: elements of social life that we might intuitively gloss as ‘ritual', but that are, in fact, integral to the everyday economic order. Here, my work builds on a long literature in Sierra Leonean ethnography. Anthropologists working in this region have often revealed how their interlocutors do not draw any sharp distinction between ‘material' and ‘immaterial' elements of the physical environment and the agencies that inhabit it (Ferme 2001; Tonkin 1979; Bellman 1984). My contribution to this literature is to explore how such apparently abstruse questions of im/materiality become relevant in people's lives through economic practice: through the everyday decisions people make, and the work they invest, in fishing, trading, and gift-exchange.

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Small, David. "Beaufort coast wind climatology and case study of a high wind event." Thesis, McGill University, 2009. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=66951.

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Tuktoyaktuk, a community along the Beaufort coast in the western Canadian Arctic, experiences serious coastal erosion during periods of strong and persistent northwesterly winds during the late summer season when the sea ice coverage reaches its annual minimum. The prevalence of strong northwesterly winds along the Beaufort coast has often been linked to the passage of powerful storms. In this study, a climatology of late summer winds at Tuktoyaktuk is compiled that links the observed wind regime to the orography of the Brooks Range. The climatology and a detailed case study of an extreme wind event indicate that an anticyclone over the Chukchi or western Beaufort Seas is conducive for cold air damming events north of the Brooks Range that alter the pressure gradient in a direction favorable for strong northwesterly geostrophic winds over Tuktoyaktuk to be mixed to the surface in a neutrally stratified atmosphere.
Tuktoyaktuk, une communauté sur la côte de Beaufort à l'ouest de l'arctique canadien, est aux prises à de graves épisodes d'érosion côtière à la fin de l'été, lorsque la couverture glacière est à son minimum et que soufflent de persistants et forts vents du nord-ouest. La prévalence de forts vents du nord-ouest le long de la côte de Beaufort a souvent été lié au passage de puissantes tempêtes. Dans cette étude, une climatologie des épisodes de vent de fin d'été est établie et mise en lien avec avec l'orographie de la chaîne de montagnes Brooks. La climatologie ainsi qu'une étude de cas détaillée d'un épisode de vents de force extrême indiquent qu'un anticyclone au dessus de la mer de Chukchi ou la mer de Beaufort conduit à un blocage d'air froid au nord de la chaîne Brooks qui modifie le gradient de pression dans une direction favorable à un mélange des forts vents géostrophiques nord-ouest au dessus de Tuktoyaktuk jusqu'à la surface dans une atmosphère stratifiée à stabilité neutre.

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Mullins, Ruth Louise. "Characterizing marine mammal stranding events along the Texas coast." Texas A&M University, 2008. http://hdl.handle.net/1969.1/86047.

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The Texas Marine Mammal Stranding Network (TMMSN) is a valuable data resource for the marine mammal community. Limitations of funding and personnel severely impact the ability of the Network to maintain impeccable databases. This research constructed an application to address database complications and focused on investigating the species identification, temporal and spatial trends for stranding events along the Texas coast. From 1980 to 2004, Tursiops truncatus accounted for approximately 80% of all stranding events. The remainder was 20 additional whale and dolphin species known to reside in the Gulf of Mexico. Tursiops truncatus strand along the entire coastline and are the only species stranding in the bays. All other species stranding are most dense along the southern coastline. The temporal scales of events revealed no linear patterns from 1980 to 2004. A unique cyclic fluctuation occurred from 1992 to 1998, including the highest yearly counts and one isolated mortality event in Port Aransas. Attempts to forecast stranding events beyond 2004 were inconclusive due to multiple factors influencing a stranding event. A bimodal seasonal trend was evident, with events peaking in the spring and fall months. Density distributions by decade isolated three frequent stranding areas: Sabine-Galveston-Brazoria counties, Galveston Shipping Channel, and Corpus Christi Shipping Channel. The final aspect analyzed spatial elaboration of events by creating six location values to describe the Texas coastline. Each event was assigned from the geographical location and the orientation of an event along the coastline. Analysis revealed the segregation of Tursiops truncatus in the bays and confirmed earlier results of density distributions. Examining the locations by time revealed a specific incident connected to a mortality event in 1992, accounting for 59% of the stranding events. Location categories were compared to the TMMSN stranding regions and the regions experienced different location frequencies. This study demonstrated how to construct a stronger database and the necessity for database accuracy. Study conclusions demonstrated the need to better isolate and research factors responsible for event distributions in time and space along the Texas coast to forecast the magnitude and location of stranding events to better aid the TMMSN response efforts.

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Albuquerque, Miguel da Guia. "Análise espaço-temporal das causas da variabilidade da linha de costa e erosão na praia do Hermenegildo, RS." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2013. http://hdl.handle.net/10183/72241.

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Na atual discussão do processo de mudanças climáticas, e seus efeitos nas zonas costeiras, o presente estudo tem como objetivo ampliar o entendimento dos fatores responsáveis pelo processo erosivo estabelecido na praia do Hermenegildo, entre os anos de 1947 e 2012, através da associação de dados oceanográficos que levam a intensificação desse processo, e dados geomorfológicos tradicionais. A partir de dados de linha de costa, obtidos através de imagens de satélite, fotografias aéreas, de diferentes épocas, e dados de GPS RTK coletados in situ, foi possível caracterizar o comportamento da linha de costa da praia do Hermenegildo em micro e mesoescala. Dados de TSM, direção e intensidade dos ventos e altura de ondas, obtidos da NOAA, também foram incorporados no estudo. Ao longo de 65 anos, a taxa de retração média da linha de costa foi de 1,68 m/ano, com os maiores picos erosivos registrados entre os anos de 1996 a 2000 (6,29 m/ano) e 2005 a 2006 (5,25 m/ano). Os intervalos com as maiores taxas de recuo são coincidentes com os períodos de ocorrência de forte El Niño e anomalias na TSM. Em anos onde esses eventos são coincidentes, em mesma intensidade, foram registradas as maiores perdas por erosão. Um comparativo feito entre os dados de TSM e retração média da linha de costa apresentaram uma correlação de 80%, num cenário onde os ventos provenientes do quadrante SW são os mais significativos. Quando comparados os dados de TSM e nível médio do mar local (obtidos por modelagem), esses não apresentam correlação significativa. Contudo, quando analisados e comparados separadamente, os dados variam coincidentemente para o mesmo intervalo temporal de forma que, quando se identificou variações na TSM, observou-se também uma variação no nível. O conhecimento do comportamento da linha de costa é fundamental para fins de planejamento e ordenamento do litoral. Dessa forma, a partir do conjunto de dados, foi efetuada uma previsão da posição futura da linha de costa para os anos de 2022, 2032 e 2100, tendo como base o ano de 2012. Estas apresentaram um recuo de 8,18 m, 22,29 m e 151,57 m, respectivamente. De posse dessas informações, um mapa de probabilidades ao processo erosivo foi gerado destacando que, o setor norte do balneário é o mais suscetível à erosão. O produto cartográfico obtido, o qual contempla informações de diferentes escalas, poderá servir como uma ferramenta importante aos gestores costeiros municipais. No que diz respeito ao estabelecimento de possíveis soluções para amenizar ou mitigar a problemática da erosão, o mapa de probabilidades à erosão dará suporte ao processo de expansão do balneário, à medida que os gestores terão mapeadas as áreas de maior e menor probabilidade ao processo erosivo.
In the context of the current discussion of climate change and its effects along the coast al zones, this study aims to broaden the understanding about the responsible factors for the well established coastal erosion at Hermenegildo beach, between the years 1947 and 2012, throughout the association of oceanographic data that may have lead to its intensification, and conventional geomorphological data. Using shoreline position data, through satellite imagery, air photographs of various periods combined with GPS RTK data collected in situ, it was possible to characterize shoreline behavior at micro and medium scale. TSM, wind strength and direction as well as wave height data from NOAA, have also been incorporated to this study. Along 65 years, mean shoreline recession has been of 1.68 m/yr, with highest erosion rates registered between 1996 and 2000 (6.29 m/yr) and between 2005 and 2006 (5.25 m/yr). The highest shoreline recession values coincide with El Niño periods and with TSM anomalies. Throughout the years when these events coincided and had the same intensity, the highest erosion rates were registered. A comparison between TSM data and mean shoreline recession demonstrated a positive correlation of 80%, in a scenario where SW winds predominate. Conversely, when TSM and mean local sea level (modeled), no significant correlation was observed. Nonetheless, when compared and analyzed separately, data varied coincidently for the same time interval, that is when variations in TSM occurred, mean sea level also varied. Understanding shoreline behavior is essential for coastal planning and development. This way, using the available data it was possible to predict future shoreline position for the years 2022, 2032 and 2100, using the 2012 shoreline position as a starting point. Resulting future shoreline positions are 8.18 m, 22.29 m and 151.57 m, respectively. Based on this information, a probabilistic map of erosion risk was prepared highlighting that the northern sector of Hermenegildo is more susceptible to erosion. The resulting cartographic product, which comprises information at various scales, may be used as an important tool for local coastal managers. Regarding the establishment of possible solutions in order to mitigate the erosion problem, the erosion probability map will give support to broaden urbanization along the beach, since the coastal managers will know which area are at higher or lower risk of erosion.

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Chan, Yuen-man, and 陳苑雯. "Field and laboratory studies of E. coli decay rate at a coastal beach with reference to storm events." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B4598864X.

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Tran, Hoa Thi. "Integration of Geospatial Technologies in Monitoring Drought Events in a Coastal Area of Vietnam (Case study: Binh Thuan Province)." Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/95471.

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Drought is a climatic event regarding prolonged "drier than normal" conditions. Precipitation deficits, crop-moisture stress, soil-water unbalance, sudden stream flow cut-offs and low carrying capacity of ecosystems are responses to drought. Drought can occur in humid to arid climates, however, drought is more severe in arid and semi-arid areas due to the fact that in those distinctive areas, water resources are extremely limited and restricted. Additionally, local ecologies and ecosystems in arid regions are very fragile. Once a water competition occurs, critical services of ecosystems such as pure water, recreation, and land productivity will be threatened. This research focuses on prolonged drought events that have been occurring more frequently in a coastal province of South Central Vietnam – named Binh Thuan. The study area is distinctive because its climate is characterized as one of the driest provinces in Vietnam. Annual rainfall in the North and near the coast of the province is less than 800 mm per year. During 6 months of dry season, there is almost no rain, or less than 50 mm. Due to precipitation deficits and high surface temperatures in recent years, meteorological droughts have occurred more frequently, and lasted longer, thereby stressing water resources for vegetation, wildlife, households, and industry. The occurrence of prolonged droughts has constrained economic activities in the coastal areas, especially agriculture and aquaculture. Furthermore, a long duration of dry conditions coupled with unsustainable land management (such as overgrazing), "drought-sensitive" soils in areas with sand and barren lands may introduce and accelerate risks of desertification processes (land productivity deterioration and unable to recover). This research uses geospatial technologies to monitor drought severity and drought impacts on land use and land cover. Chapter 1 is a brief introduction and literature review of the drought context in Binh Thuan Province to place the research questions and objectives in content. Chapter 2 discusses the occurrence of meteorological droughts in Binh Thuan Province, then proposes climatic indices able to monitor this type of drought. Chapter 3 focuses on explaining and assessing uneven dry conditions that stressed vegetation health in the study area. This chapter investigates spatiotemporal distributions and frequencies of prolonged agricultural droughts using remotely sensed data and anomalies of precipitation distribution. Results indicate that coastal areas in the North of Binh Thuan are subject to severe droughts. Chapter 4 assesses human impacts on land management and practices in the study area during drought periods. Results show that in recent years (2010 to present), local governments and residents have implemented strategies to prevent sand dominance and to adapt to water shortages during dry seasons, such as vegetative cover, crop rotation with drought-tolerant plants and wind breaks. Accuracy was assessed using field data collected in the summer of 2016, in conjunction with Google Earth imagery. In summary, this dissertation enhances understanding of drought events and impacts in Binh Thuan Province by considering different types of drought - meteorological and agricultural drought, and interactions of drought and human impacts upon land management and land practices during dry periods. Furthermore, findings and results of this research have demonstrated the effectiveness of remotely sensed datasets, and other geospatial technologies, such as geographic information systems, in modeling drought severity and in examining efforts and drought-adaptive practices of local residents. This work is a valuable foundation on which further studies can build to support policy development to protect and reserve soil-land productivity in Binh Thuan and other coastal regions of Vietnam affected by prolonged droughts.
Doctor of Philosophy
Drought is a temporal climatic event with "drier than normal" conditions. While drought can occur in any climates, it can be more extreme in arid and semi-arid areas where annual rainfall and water resources are limited. Depending on types of drought, its presences and impacts may differ: (1) meteorological drought relates to a decrease of average rainfall/snowfall may resulting in moisture stress, (2) hydrological drought leads to a reduction of streamflow and groundwater, and (3) agricultural drought influences soil-water-crop balance or vegetation health. Prolonged drought – abnormally long duration of dry conditions, coupled with unsustainable management in water and land practice may cause losses of land productivity, promote soil erosion, and result in sand dominance in coastal areas. These land degradation processes can lead to "a desert-like condition" in impacted areas. This research concerns drought and its impacts in a coastal province in South central Vietnam, Binh Thuan. The study area is distinctive because its climate is characterized as one of the driest provinces in Vietnam. Annual rainfall in the North and near the coast is less than 800 mm per year, and during the 6 months of the dry season, there is almost no rain, or less than 50 mm. Due to precipitation deficits and high surface temperatures in recent years, meteorological droughts have occurred more frequently and lasted longer, stressing water resources for vegetation, wildlife, households, and industry. Additionally, unsustainable land management, such as overgrazing, coupled with movements of sand and barren lands from the coast inland, have accelerated the risks of land degradation. This research applies an integration of geospatial technologies for monitoring drought severity and impacts on land management and illustrates how local people have adapted to droughts.

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Robert, Marie. "A study of El Ninõ events along the British Columbia coast /." Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=55527.

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The El Nino phenomenon has a major impact over wide regions of the Pacific and possibly all over the world. The purpose of this thesis was to study its effects, specifically along the coast of British Columbia. An analysis of sea-surface temperature, sea-surface salinity and sea-level height was made with respect to El Nino events. Based on the results of that analysis, a model was developed. The model uses Kelvin wave dynamics, and can be used to predict the approximate time and magnitude of the sea-surface temperature anomaly created by an El Nino event. This prediction can be useful for fishermen because the anomaly of temperature has a major effect on the distribution pattern of fish. In conclusion, an analysis of water temperature and salinity anomalies as a function of depth as well as offshore distance was made.

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Sambo, Beatrice <1995&gt. "Building the resilience of coastal systems to extreme events: the case of the Metropolitan City of Venice and its lagoon." Master's Degree Thesis, Università Ca' Foscari Venezia, 2020. http://hdl.handle.net/10579/16973.

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The significant increases in magnitude and frequency of climate related extreme events are placing considerable economic, logistical, and at times social strains upon coastal systems. Within the BRIDGE project, a scenario-informed multicriteria methodology was designed to integrate qualitative (i.e. local stakeholders’ preferences) and quantitative information (i.e. climate change projections) in a unique framework supporting the enhancement of coastal systems resilience to extreme events. Different group of local stakeholders (e.g. local authorities, civil protection agencies, SMEs, NGOs) were involved to identify critical functions (i.e. coastal systems and processes that are likely to be affected by extreme events) and propose risk management initiatives/measures that can be strategic to enhance overall system resilience under the future climate scenarios, and that they wish to consider for prioritization. Most representative scenarios describing main climatic threats (e.g. storm surges, floods, heatwaves, drought) that could affect coastal areas of interests were selected and represented based on projections of Regional Climate Models for medium term period (e.g. 2021–2050). Multicriteria Decision Analysis (MCDA) was finally used to compare the initiatives and to select the optimal ones across different scenarios, using the set of critical functions and local stakeholders’ perspectives as the basis for the ranking. The methodology was tested in the Metropolitan City of Venice to assess the resilience of proposed risk management projects against the impacts of climate change scenarios envisioned for the area.

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Freel, R. E. "The characteristics and geomorphological impact of 20th century extreme storm-surge events on a coastal dune site of Atlantic North Ireland." Thesis, Queen's University Belfast, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.411226.

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The vulnerability of north Ireland’s Atlantic coastline is assessed for the first time based on Irish tide-gauge records. This study attempts to identify the response of a coastal dune system to extreme coastal forcing in the past, in order to understand how coastal dunes may respond in the future under global warming conditions. Decadal-scale change in foredune presence and loss has been observed at Five Fingers Strand, north Ireland. It appears that these changes are not conditioned by variation in sea level per se, but rather by extreme forcing that occurs in surge and wave climates generated by severe coastal storms. A storm ‘training set’ has been developed by which to identify the synoptic conditions required to promote extreme surge elevations. This training set also enables hindcasting of the wave climate associated with such events. Coastal sensitivity has been addressed through thresholds in storm activity leading to foredune loss in terms of the joint occurrence of a number of controlling storm variables. Results suggest that coastal sensitivity is primarily a function of extreme surge intersecting a high water (tidal) elevation, with surge primarily a function of central pressure and storm trajectory. These thresholds are further conditioned by antecedent beach morphology. The periods between these dune-stripping events appear to be characterised by foredune re-building. Therefore, while the disappearance of foredunes may operate on a decadal scale, the trigger may be a single storm operating on a (sub-) daily scale. The role of the North Atlantic Oscillation in extreme coastal forcing is tentative in that it appears to influence aggregate storm activity at a quasi-decadal scale rather than at individual storm level.

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Mazas, Franck. "Evènements météo-océaniques extrêmes." Thesis, Paris Est, 2017. http://www.theses.fr/2017PESC1148/document.

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Cette thèse sur travaux vise à rassembler et unifier les travaux réalisés sur le sujet des évènements météo-océaniques extrêmes depuis 2009, dans le cadre de mon travail à SOGREAH, devenu depuis ARTELIA. À mesure que progressaient ces travaux, un thème central a progressivement apparu : la notion d'évènement, tel qu'une tempête. Ce concept fournit un cadre robuste et pertinent, en particulier dans le cas des extrêmes multivariés (par exemple, la probabilité d'occurrence conjointe des vagues et des niveaux marins), ainsi qu'une meilleure compréhension de la notion de période de retour, très utilisée dans le domaine de l'ingénierie.Les principaux résultats des travaux réalisés au cours de la décennie écoulée sont les suivants :- mise à jour de la méthodologie de détermination des houles ou vents extrêmes :- développement et justification d'un cadre en deux étapes pour la modélisation sup-seuil des extrêmes univariés (méthode du renouvellement), introduisant la notion d'évènement et la séparation des seuils physique et statistique,- proposition d'outils pratiques pour le choix du seuil statistique,- introduction de la méthode du bootstrap paramétrique pour le calcul des intervalles de confiance,- identification d'un comportement problématique de l'Estimateur du Maximum de Vraisemblance et proposition d'une solution : utilisation de distributions à trois paramètres avec l'estimateur des L-moments,- application du cadre POT (Peaks-Over-Threshold) à la Méthode des Probabilités Jointes (JPM) pour la détermination des niveaux marins extrêmes :- distinction entre les valeurs séquentielles et les pics des évènements à l'aide d'indices extrémaux pour les surcotes et les niveaux marins,- construction d'un modèle mixte pour la distribution des surcotes,- raffinements pour le traitement de la dépendance marée-surcote,- application du cadre POT-JPM pour l'analyse conjointe des hauteurs de vagues et des niveaux marins :- proposition d'une procédure alternative d'échantillonnage,- analyse séparée de la marée et de la surcote dans le but de modéliser la dépendance entre la hauteur de vagues et la surcote ; avec incorporation dans la distribution conjointe de la hauteur de vagues et du niveau marin à l'aide d'une opération de convolution 2D1D,- utilisation de copules des valeurs extrêmes,- présentation améliorée du chi-plot,- introduction d'une nouvelle classification pour les analyses multivariées :- Type A : un phénomène unique décrit par différentes grandeurs physiques qui ne sont pas du même type,- Type B : un phénomène fait de différentes composantes, décrits par des grandeurs physiques du même type d'un composant à l'autre,- Type C : plusieurs phénomènes décrits par des grandeurs physiques qui ne sont pas du même type,- interprétation de la signification des évènements multivariés :- lien avec l'échantillonnage,- lien avec les différentes définitions de la période de retour,- dans le cas bivarié : transformation d'une distribution conjointe de variables descriptives de l'évènement vers la distribution des couples de variables séquentielles,- génération de graphes de srotie alternatifs tels que les contours d'iso-densité pour les couples de variables séquentielles,- un package R dédié, artextreme, pour l'implémentation des méthodes ci-dessus
This PhD on published works aims at unifying the works carried out on the topic of extreme metocean events since 2009, while working for SOGREAH then ARTELIA.As these works went along, a leading theme progressively appeared: the notion of event, such as a storm. This concept provides a sound and relevant framework in particular in the case of multivariate extremes (such as joint probabilities of waves and sea levels), as well as a better understanding of the notion of return period, much used for design in the field of engineering.The main results of the works carried out in the last decade are as follows:- updating of the methodology for determining extreme wave heights or wind speeds:- development and justification of a two-step framework for extreme univariate over-threshold modelling introducing the concept of event and the separation of the physical and statistical thresholds,- proposal of practical tools for choosing the statistical threshold,- introduction of the parametric bootstrap approach for computing confidence intervals,- identification of a problematic issue in the behaviour of the Maximum Likelihood Estimator and proposal of a solution: use of 3-parameter distributions along with the L-moments estimator,- application of the POT framework to the Joint Probability Method for determining extreme sea levels:- distinction between sequential values and event peaks through extremal indexes for surge and sea level,- construction of a mixture model for the surge distribution,- refinements for handling tide-surge dependence,- application of the POT-JPM framework for the joint analysis of wave height and sea level:- proposal of an alternative sampling procedure,- separate analysis of tide and surge in order to model the dependence between wave height and surge to be incorporated in the joint distribution of wave height and sea level thanks to a 2D1D convolution operation,- use of extreme-value copulas,- improved presentation of the chi-plot,- introduction of a new classification for multivariate analyses:- Type A: a single phenomenon described by different physical quantities that are not of the same kind,- Type B: a phenomenon made of different components, described by physical quantities of the same kind between one component and another,- Type C: several phenomena described by physical quantities that are not of the same kind,- interpretation of the meaning of multivariate events:- link with the sampling procedure,- link with the different definitions of the return period,- in the bivariate case: transformation of the joint distribution of event-describing variables into the joint distribution of sequential pairs,- generation of alternative output plots such as contours of density for sequential pairs;- a dedicated R package, artextreme, for implementing the methodologies presented above

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Acheampong, Henrietta. "Destination Branding : Focusing on Events Contribution on an Urban Level." Thesis, Södertörns högskola, Turismvetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-43683.

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Today´s tourism sector is one of the fastest-growing sectors in the world and that has greatly influenced destinations. The recent development in the use of events to build, reinforce, and increase destination branding has received huge recognition. This paper examines the engagement of public and private stakeholders in creating or buildingthe brand of Cape Coast as a destination. It is important to have all various stakeholders to understand the vision towards a common goal. This is because to build destination branding thebrand needs to replicate the authenticity of the identity of the destination which in turn willassist in differentiating its goods and services from other competitors. Destination branding is seen as an important strategic tool for tourist destination since it underlines the huge significantcontributor to the economic development and market opportunities. Cape Coast city is known for its attractions which is visited by both international and domestic tourists. The aim of this research is to explore how stakeholders can contribute in creating CapeCoast´s destination brand by using events. To achieve this aim, this research uses a qualitativemethod in the form of telephone interviews, which were conducted with representatives of thetourism sector in Cape Coast, Ghana. The collected data were analysed by using content analysis. The findings proved that there is a lack of continuity from the government, that thereis inadequate brand communication among various stakeholders. Furthermore, this researchbrought to light that there is a need for product diversification and inadequate infrastructure in Cape Coast.The overall research openly gives an insight concerning the importance of destination branding, roles of stakeholders, events contribution to brand identity, diversification of products, communication platforms, and challenges of branding a destination in Cape Coast.

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James, Carl S. "Evaluation of COAMPS performance forecasting along coast wind events during a frontal passage." Thesis, Monterey, California. Naval Postgraduate School, 2005. http://hdl.handle.net/10945/2281.

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Approved for public release, distribution is unlimited
Performance of high resolution mesoscale models has been in a continuous state of refinement since their inception. Mesoscale models have become quite skillful in forecasting synoptic scale events such as mid-latitude cyclones. However, atmospheric forcing becomes a much more complicated process when faced with the challenge of forecasting near topography along the coastline. Phenomena such as gap flows, blocked flow winds and low level stratification become important to predictability at these scales. The problem is further complicated by the dynamics of a frontal passage event. The skill of mesoscale models in predicting these winds is not as well developed. This study examines several forecasts by the Coupled Ocean Atmospheric Mesoscale Prediction System (COAMPS) during frontal passage events for the Winter of 2003-2004. An attempt is made to characterize the predictability of the wind speed and direction both before and after frontal passage along the California coast. Synoptic forcing during this time is strong due to the effects of the mid-latitude cyclones propagate across the Pacific. The study's results indicate that the wind field predictability is subject to several consistent errors associated with the passage of fronts over topography. These errors arise due to difficulty in the model capturing weak thermal advection events and topographic wind funneling. The deficiencies in model representation of topography contributes to these errors.
Lieutenant, United States Navy

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James, Carl Sim. "Evaluation of COAMPS Forecasting performance of along coast wind events during frontal passages /." Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2005. http://library.nps.navy.mil/uhtbin/hyperion/05Mar%5FJames.pdf.

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Thesis (M.S. in Meteorology and Physical Oceanography)--Naval Postgraduate School, March 2005.
Thesis Advisor(s): Wendell A Nuss. Includes bibliographical references (p. 61-62). Also available online.

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Biccard, Aiden. "Fast food : the transport of particulate organic matter over an upwelling event on the west coast of southern Africa." Bachelor's thesis, University of Cape Town, 2007. http://hdl.handle.net/11427/25931.

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Differences in transport, composition and supply of particulate organic matter (POM), as a food source for coastal consumers, were investigated between an exposed headland (Cape Columbine) and a sheltered bay (Elandsbaai) in the southern Benguela. Physical data, in agreement with previous studies, showed that Cape Columbine is situated within an upwelling center and Elandsbaai within an upwelling shadow. Three distinct oceanographic conditions, upwelling, relaxation and downwelling, were discemable from wind, current and temperature data at each site. Upwelling was most prevalent at Cape Columbine in contrast to relaxation at Elandsbaai. Significant differences (P < 0.00001) in chlorophyll a concentration, quantities of organic carbon and % kelp-derived carbon were found between the two sites. In addition, significant differences (P < 0.0001) in chlorophyll a concentration, quantities of organic carbon and % kelp-derived carbon were found between the different oceanographic conditions: upwelling, relaxation and downwelling. A significant interaction (P < 0.00001) for % kelp-derived carbon was found between site and oceanographic conditions. Tests within study sites revealed significantly higher chlorophyll a concentrations in the euphotic zone, as expected. Furthermore, chlorophyll a concentrations showed a significant decrease with distance offshore at Elandsbaai. Percentage contribution of kelp-derived carbon (max = 36%) to POM was lower than predicted and surprisingly lower than values reported in previous works (77%). No stratification of kelp-derived matter or organic carbon was observed in the water column at both sites. It is likely that sampling stations were too shallow i.e. water column was well mixed as a results of nearshore turbulence. In terms of food supply to coastal consumers, upwelling episodes at Cape Columbine resulted in significantly high import of kelp matter into the nearshore water column. In contrast, phytoplankton, constituted the primary food source for both sites during relaxation and downwelling episodes. It is clear that different oceanographic conditions between an exposed headland and a sheltered bay have profound implications regarding the transport, composition and supply of POM, as a source of food to coastal communities.

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Gagliardi, Marcelo Henrique. "Análise de Riscos Costeiros a Eventos Atmosféricos Extremos no Litoral Sul do Estado de São Paulo - Estudo de caso na região da Desembocadura de Cananéia." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/21/21136/tde-09042014-183047/.

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O atual estudo visa cooperar na compreensão dos efeitos da passagem de tempestades extremas sobre os sistemas litorâneos através do estudo de caso na Desembocadura de Cananéia, localizada na Ilha Comprida - SP. O trabalho contou com campanhas de campo para levantamento de dados topográficos e coletas de sedimentos, análises das condições ambientais atuantes durante o período dos campos, determinação da evolução da linha de costa através da análise de fotos aéreas e imagens de satélite e simulações numéricas para caracterizar o regime de ondas atuante na região. Foram produzidos mapas temáticos para representar as cotas de inundação associadas a ocorrência de marés meteorológicas .Os resultados indicaram que a ação das ondas de tempestade se da principalmente por meio do transporte onshore-offshore nas escalas temporais diária e mensal. A evolução da linha de costa obtida apontou para maior eficiência das correntes de deriva litorânea na escala decadal. A comparação entre os resultados topográficos/volumétricos e da evolução da linha de costa evidenciam uma tendência erosiva nas adjacências do Pontal de Fora associada à incidência de eventos atmosféricos extremos para o período entre 2001 e início de 2012. Os resultados das determinações das cotas de inundação apontam que os maiores impactos locais associados às mudanças climáticas serão provenientes das alterações na frequência de ocorrência e intensidade das tempestades
The current study aims to cooperate in the knowledge about the effects of the occurrence of extreme storms on coastal systems through the case study of the Desembocadura de Cananéia, located on Ilha Comprida - SP. The work included campaigns of field survey to collect topographic data and sediment samples, analysis of environmental conditions during the period of surveys, determination of the shoreline evolution through analysis of aerial photos and satellite images and numerical simulations to characterize the wave regime present in the region. Thematic maps were produced to represent the flood hazard associated with the occurrence of storm surges. Results indicated that the action of storm waves occurs primarily by means of the onshore-offshore transport on daily and monthly time scales. The evolution of the shoreline obtained pointed to greater efficiency of longshore currents on the decadal scale. The comparison between the topographic/volumetric results and the evolution of the coastline shows an erosive trend in the vicinity of the Pontal de Fora associated with the incidence of extreme weather events for the period between 2001 and early 2012. The results of the determinations of flood hazard areas points out that the major local impacts related to the global climate changes will come from variations in the frequency of occurrence and intensity of storms

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Bronikowski, Jason Lee. "Sedimentary environments and processes in a shallow, Gulf Coast Estuary-Lavaca Bay, Texas." Texas A&M University, 2004. http://hdl.handle.net/1969.1/1098.

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Sedimentation rates in sediment cores from Lavaca Bay have been high within the last 1-2 decays within the central portion of the bay, with small fluctuations from river input. Lavaca Bay is a broad, flat, and shallow (<3 m) microtidal estuary within the upper Matagorda Bay system. Marine derived sediment enters the system from Matagorda Bay, while two major rivers (Lavaca & Navidad) supply the majority of terrestrially derived sediment. With continuous sediment supply the bay showed no bathymetric change until the introduction of the shipping channel. Processes that potentially lead to sediment transport and resuspension within the bay include wind driven wave resuspension, storm surges, wind driven blowouts, and river flooding. These processes were assessed using X-radiographs, grain size profiles, and 210Pb and 137Cs geochronology of sediment diver cores. In six cores the upper 10 cm of the seabed has been physically mixed, where as the rest showed a continuous sediment accumulation rate between 0.84-1.22 cm/yr. Sidescan sonar and subbottom chirp sonar data coupled with sedimentological core and grab samples were used to map the location and delineate the sedimentary facies within the estuarine system in depths >1 m. Five sedimentary facies were identified in Lavaca Bay and adjacent bays, they are: 1) estuarine mud; 2) fluvial sand; 3) beach sand; 4) bay mouth sand; and 5) oyster biofacies. Of the five facies, Lavaca Bay consists primarily of estuarine mud (68%). Pre-Hurricane and post-Hurricane Claudette cores were obtained to observe the impact to the sedimentary processes. The north and south Lavaca Bay were eroded by 10 cm and 2-3 cm, respectively. Cox Bay and Keller Bay saw a net deposition of 2-3 cm.

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Perriquet, Marie. "Characterization of the hydrodynamics and saltwater wedge variations in a coastal karst aquifer in response to tide and precipitation events (Bell Harbour catchment, Co. Clare, Ireland)." Thesis, Montpellier 2, 2014. http://www.theses.fr/2014MON20042/document.

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La côte ouest irlandaise située dans les comtés de Clare et Galway est depuis récemment affectée par une augmentation de la fréquence des inondations et une montée du niveau marin. L'impact de ces changements climatiques se fait particulièrement ressentir au niveau des aquifères karstiques côtiers de ces régions, tel que le bassin karstique de Bell Harbour (~50 km²) sélectionné dans le cadre de ce projet: le positionnement d'un biseau salé dans cet aquifère est clairement dû à l'interaction entre sa recharge liée aux événements pluvieux et la forte influence de la marée. Des données (niveaux d'eau et conductivités spécifiques) ont été collectées à l'aide de sondes, à deux sources côtières, six forages, trois lacs et au milieu de la baie durant des périodes prolongées. Trois types d'environnement hydrodynamiques (conduits, fissures et matrices) ont été définis pour chacun des six forages en comparant deux méthodes qui se sont avérées cohérentes entre-elles. Les variations des conductivités spécifiques combinées à la chimie des eaux des six forages et de lacs ont permis d'évaluer l'étendue du biseau salé dans l'aquifère en fonction de la recharge de l'aquifère et des cycles de marée haute/basse et vives eaux/basses eaux: l'étendue du biseau salé dépend des propriétés hydrodynamiques de l'aquifère mais aussi de l'influence relative de la recharge et de la marée sur les niveaux piézométriques, induisant chacun des comportements opposés. Ainsi, la compétition entre la recharge et la marée contrôle l'intrusion d'eau de mer dans l'aquifère, ce qui explique les changements spatio-temporels du biseau salé dans l'aquifère. Les fortes amplitudes de marée semblent être le moteur des brèves intrusions salines dans l'aquifère proche de la rive alors que la position du niveau piézométrique semble influencer l'intensité de cette augmentation de la salinité. La recharge karstique de la région est suffisamment importante tout au long de l'année pour que le biseau salé ne s'étende pas plus loin qu'un kilomètre de la rive. La diminution des précipitations durant l'été (~10 %) ainsi que l'augmentation du niveau marin prévues pour les prochaines décennies, contribueront certainement à une intrusion plus importante du biseau salé dans l'aquifère
Low-lying coastal areas in the west of Ireland, such as the Galway and Clare coasts, have seen recent increases in flooding frequencies coupled with overall increases in sea level. The impacts of these changes are most strongly felt in coastal karst catchments and this study focuses on one such area, the Bell Harbour catchment (~50 km²), where there is a clear interaction between rainfall inputs and tidal influences, to create a terrestrial salt water wedge. Data (specific conductivity and water levels) have been collected at two coastal springs, six boreholes, three lakes, and from discrete locations in the middle of the bay, using dedicated loggers over extended periods. Two approaches that provided consistent results were used to explain the different hydrodynamic behaviours identified in the boreholes (conduits, fissures and matrix flows). Specific conductivity variations and water chemistry measured inland allowed for assessment of the spatial extent of the saltwater wedge into the aquifer as a function of both karst recharge and tidal movements at high/low and neap/spring tidal cycles. The extent of the saltwater wedge depends on the intrinsic properties of the aquifer but also on the relative influence of the recharge and the tide on groundwater levels, which induce opposite behaviours. This dynamic between recharge and the tide thus controls the seawater inputs, hence explaining temporal and spatial changes in the saltwater wedge in this coastal karst aquifer. Strong tidal amplitudes seems to be the motor of sudden saltwater intrusion observed in the aquifer near the shore while the relative elevation of the groundwater appears to influence the intensity of the salinity increase. The magnitude of annual recharge in the area is high enough to limit saltwater intrusion to no more than about one kilometre inland from the shore. Given the anticipated decreases in summer precipitation (~10 percent), coupled with anticipated sea level rises, the extent of the saltwater wedge into the aquifer is likely to increase in coming decades

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Keck, Jennifer R. "Changes in Coral Populations on the Northwest Coast of Roatan, Honduras, Subsequent to the 1998 Coral Bleaching Event and Hurricane Mitch." NSUWorks, 2004. http://nsuworks.nova.edu/occ_stuetd/280.

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Long term monitoring of coral reefs on the northwest coast of Roatán, Honduras, has documented significant changes in coral cover over a seven-year period. Twenty photographic quadrats were permanently installed at approximately 12 m depth at each of three study sites located on the northwest coast of Roatán. Photographs were taken at six or twelve month intervals from 1996 through 2003. This observation period included a massive bleaching event which began in late-September of 1998, and Hurricane Mitch which struck in October of the same year. A measurement of projected surface area (PSA, cm2) was used to estimate total coral coverage. Changes in colony number, percent cover, species diversity and recruitment of all scleractinian corals were monitored within the quadrats. During the seven-year period, living coral cover decreased significantly from 30-34% to 17-20%. This represents net losses ranging between 32% and 50%. The greatest loss occurred in the year following the bleaching event and Hurricane Mitch and was largely due to the decline of the dominant reef building species Montastrea annularis, M. faveolata, and M. franksi. These three species accounted for 56% of total hard coral cover in 1996 and only 32% at the conclusion of the observation period. A sharp reduction in the total number of living colonies in the quadrats was observed with 217 of the 532 original colonies (41%) suffering complete mortality. While 117 coral recruits were identified during this period, recruitment mortality was high (40%) with only two cases of the massive frame building Montastrea species recruiting into the photostations. A combination of at least three factors have contributed to changes in the benthic community observed during this investigation: (1) the massive coral bleaching event in the fall of 1998 which disproportionately affected Montastrea spp.; (2) a category 5 hurricane; and (3) increased anthropogenic stress in the form of sedimentation and nutrient enrichment as the result of new and unregulated development.

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Van, der Borch van Verwolde Emile. "Characteristics of extreme wave events and the correlation between atmospheric conditions along the South African coast." Master's thesis, University of Cape Town, 2004. http://hdl.handle.net/11427/11055.

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Includes bibliographical references (leaves 69-72).
Characteristics of extreme wave events along the coast of South Africa were researched through a dataset obtained by CSIR wave recording network at four locations. The locations from west to east are Slangkop, FA-Platform (Agulhas bank), East London and Richards Bay. The longest dataset available was the 25-year dataset at Slangkop measured by accelerometer wave buoys. In the subsequent years the wave recording network along the South African coast was expanded to six locations at present.

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Alharbi, Mohammad Mosaed Eid Alahmadi. "Analysis of extreme precipitation events over the eastern Red Sea coast for recent and future climate conditions." Thesis, University of Birmingham, 2018. http://etheses.bham.ac.uk//id/eprint/8603/.

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The investigation of extreme precipitation events over the western coast of Saudi Arabia is necessary to estimate their potential impact on both socioeconomic activities and the regional environment. The current study aims at understanding the atmospheric dynamics leading to extreme precipitation, to improve weather forecasting in the target region and the development of long-term adaptation policies. Preliminary results reveal that extreme precipitation events in this region occur during the wet season (Nov–Jan). The synoptic mechanisms of these events are a function of the complex interaction between tropical, subtropical and middle-latitude dynamics. The synoptic dynamic processes were identified by a subjective study of the highest 30 extreme events. In addition, the weather circulation patterns (WCPs) of all extreme events were classified objectively by means of an empirical orthogonal function (EOF) analysis based on the mean sea level pressure. WCPs were linked with synoptic dynamic processes and teleconnected with large-scale climate variability modes. Furthermore, WCPs, precipitation and data regarding other atmospheric variables from different regional climate models were used to investigate future changes in extreme precipitation events under climate change. The most important weather circulation patterns, which are associated with extreme precipitation events, were identified. The possibility of extreme precipitation events increases with great uncertainty.

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Oltmanns, Marilena. "Strong wind events across Greenland's coast and their influence on the ice sheet, sea ice and ocean." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/98825.

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Thesis: Ph. D., Joint Program in Physical Oceanography (Massachusetts Institute of Technology, Department of Earth, Atmospheric, and Planetary Sciences; and the Woods Hole Oceanographic Institution), 2012.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 129-143).
In winter, Greenland's coastline adjacent to the subpolar North Atlantic and Nordic Seas is characterized by a large land-sea temperature contrast. Therefore, winds across the coast advect air across a horizontal temperature gradient and can result in significant surface heat fluxes both over the ice sheet (during onshore winds) and over the ocean (during offshore winds). Despite their importance, these winds have not been investigated in detail, and this thesis includes the first comprehensive study of their characteristics, dynamics and impacts. Using an atmospheric reanalysis, observations from local weather stations, and remote sensing data, it is suggested that high-speed wind events across the coast are triggered by the superposition of an upper level potential vorticity anomaly on a stationary topographic Rossby wave over Greenland, and that they intensify through baroclinic instability. Onshore winds across Greenland's coast can result in increased melting, and offshore winds drive large heat losses over major ocean convection sites. Strong offshore winds across the southeast coast are unique over Greenland, because the flow is funneled from the vast ice sheet inland into the narrow valley of Ammassalik at the coast, where it can reach hurricane intensity. In this region, the cold air, which formed over the northern ice sheet, is suddenly released during intense downslope wind events and spills over the Irminger Sea where the cold and strong winds can drive heat fluxes of up to 1000 W m-2, with potential implications for deep water formation. Moreover, the winds advect sea ice away from the coast and out of a major glacial fjord. Simulations of these wind events in Ammassalik with the atmospheric Weather Research and Forecast Model show that mountain wave dynamics contribute to the acceleration of the downslope flow. In order to capture these dynamics, a high model resolution with a detailed topography is needed. The effects of using a different resolution locally in the valley extend far downstream over the Irminger Sea, which has implications for the evolution and distribution of the heat fluxes.
by Marilena Oltmanns.
Ph. D.

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Ireton, Greg S. "Classification of summertime West Coast fog and stratus events and the development of fog and stratus forecast techniques." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2001. http://handle.dtic.mil/100.2/ADA397067.

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Thesis (M.S. in Meteorology and Physical Oceanography)--Naval Postgraduate School, Sept. 2001.
Thesis advisor: Nuss, Wendell. "September 2001." Includes bibliographical references (p. 125-129). Also Available in print.

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Ramulifho, Aluwani Elijah. "Variability and characterizations of wind events over the Cape Columbine region along the west coast of South Africa." Master's thesis, University of Cape Town, 2012. http://hdl.handle.net/11427/9810.

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Includes bibliographical references.
Wind data over Cape Columbine is investigated over a 38 year long time series to determine whether there are noticeable changes or variability through time. The long period dataset is collected using an Automatic Weather Station. Diurnal and seasonal to annual characterizations of wind together with occurrences of related events are established. Other linkages with synoptic to near-global (e.g., ENSO) scale circulations are investigated by examining relationships with other meteorological variables. This is achieved by complimenting long term data series with data from the new technologically advanced Automatic Weather Station (AWS). From the new AWS, several relationships and connections between different atmospheric variables were developed. These include the relationship between Air Temperature and Humidity, Wind Speed and Atmospheric Pressure, and Wind Direction and Rainfall. The AWS is able to monitor the passage of synoptic (e.g., cold fronts) and mesoscale (e.g., coastal low) weather systems. Passages of cold fronts over time could easily be detected by utilizing all the different variables as recorded by the AWS (Air Temperature, Wind Speed and Direction, Relative Humidity, Atmospheric Pressure and Rainfall). The most significant atmospheric system that passed over Cape Columbine over the 2009/10 summer was a deep low pressure system, where a significant amount of rainfall, atmospheric pressure depression and drop in temperature were witnessed. There were 17 upwelling events during this six months study period. Several of them were short-lived at 4 to 6 day durations, and the longest upwelling event occurred on the 24th December 2009 and lasted until January 14th 2010. An investigation into the variability in characteristics and behavior of wind signals at Cape Columbine was conducted. The study investigated wind behavior for the period 1957 to 1995 with data collected from a point source Automatic Weather Station. Apart from the characteristics of wind over time period, linkages with large scale circulations, frequency and duration of these wind events occurrences were studied. These were achieved by partitioning the study period into different time scales; namely, the diurnal, seasonal, inter-annual and the decadal. On the diurnal time scale, a strong variability in wind strength over the course of each day due to the land/sea breeze existed. Seasonally, the wind regime in Cape Columbine was found to be driven by the latitudinal shifting of the semi-permanent South Atlantic Anticyclone. However, there are pre-dominant southerly winds throughout the year. The long record showed the possible influence of ENSO and the Benguela Niño on interannual and decadal variations in the winds at Cape Columbine.

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Burgess, Peter Mark. "A quantitative forward modelling analysis of the controls on passive rift-margin stratigraphy." Thesis, University of Oxford, 1994. http://ora.ox.ac.uk/objects/uuid:1249833d-ef11-4327-bdbd-5d0c40faa29e.

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A quantitative forward model has been developed to investigate the controls on the deposition, erosion, and preservation of passive rift margin stratigraphy. The model includes thermal subsidence, variable absolute sealevel, flexural isostasy, subaerial and submarine deposition on fluvial and marine equilibrium profiles, and the facility to vary sediment supply through time. Results from the quantitative model can be used to reproduce elements of the sequence stratigraphic depositional model. Conducting sensitivity tests demonstrates that variables such as sediment supply and fluvial profile behaviour are likely to be of equal importance to thermal subsidence and eustasy in passive margin stratigraphy. Sensitivity tests with the quantitative model also demonstrate the problems associated with attempting to use a discretised stratigraphic model to investigate unforced cyclicty resulting from complex interactions in stratigraphic systems. Although the model appears capable of producing such unforced cyclical behaviour, this cyclicity is shown to be due to a numerical instability within the model which occurs with certain initial conditions and assumptions. The applicability of the model to observed stratigraphy is tested by comparing specific model output to patterns of stratigraphy from the North American Atlantic margin. The results from this test demonstrate that although the model is in many respects simplistic when compared to the complexities of natural systems, it is nevertheless capable of reproducing some of the basic elements of the observed stratigraphic patterns.

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Fredline, Elizabeth. "Host Community Reactions to Major Sporting Events: The Gold Coast Indy and the Australian Formula One Grand Prix in Melbourne." Thesis, Griffith University, 2000. http://hdl.handle.net/10072/366728.

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It is a widely held and not unfounded belief, that major events stimulate the local economy and 'showcase' the region to the world, potentially promoting future tourism and business activity. This is one of the major reasons that there is increasing private and public sector support for events based economic development strategies. There are other important positive impacts that are often associated with the staging of events, many of which may directly benefit the local population, including the development of facilities and infrastructure, entertainment and social opportunities, and a sense of pride brought about by playing host to a major event. However, it is also clear that there are outcomes of staging an event that have a negative impact on the local population. Any event attracting large numbers of visitors to a relatively small area is likely to create some problems with noise, traffic, crowding and disruption. There are also likely to be other costs specific to the event or its implementation. While some of the costs and benefits of an event may affect the whole community, others tend to impact on certain subgroups of the population. For example, residents who are involved in tourism may receive a direct economic benefit, and those who have a particular interest in the theme of the event socially and psychologically benefit, to the extent that they are entertained by it. Similarly, some subgroups are more affected than others by the negative impacts, particularly those living (or conducting their routine activities) closest to the event's focal point. The issue of the relative costs and benefits is therefore compounded by concerns about distributive justice. This dissertation examines the ways in which local residents react to the staging of a major sporting event within their community. Two case studies, involving the Formula One Grand Prix in Melbourne and the Gold Coast Indy Car Race, were examined within a framework that combined aspects of traditional methods of investigating host community perceptions of tourism with social representations theory. Social representations are the ways in which people perceive various phenomena in the world around them. By identifying these different 'patterns' of perceptions, and profiling the subgroups of the community who hold them, it is possible to gain a better understanding of both the tangible and intangible impacts of events, and how they differentially affect the quality of life of local residents. Through a combination of quantitative and qualitative methods, five different ways of perceiving the impacts of these events were examined. The five levels can be regarded as points along a continuum, ranging from extremely negative to very positive. The largest group identified, in the middle of the continuum, demonstrated ambivalence in terms of their views on the impact of the event on their quality of life. However, given that they perceived a slightly positive overall community impact, and were largely in favour of the continuation of the event, they can be regarded as being more similar to the positive groups. In profiling the residents who held each of the representations identified, it was found that the most negative group was generally comprised of those residents whose routine activity space regularly included the focal points of the respective events. Very few members of this group had any financial involvement in tourism, and almost all of them were totally disinterested in motor racing. At the other end of the continuum, in the most positive group, very high levels of interest in motor sport were observed, and more than half of this group worked in tourism or at least perceived some boost to levels of trade in their industry because of the event. The ambivalent group was characterised by low levels of contact with the areas around the respective tracks. They generally lived a long distance away and rarely travelled to the region. The investigation of the spatial variation in the perception of event impacts was supplemented through a Geographic Information Systems Analysis, which mapped the perceptions of a number of impacts across the two cities. Finally, an examination of qualitative data, collected via open-ended questions presented to each respondent, provided greater depth of understanding of the basis for differing social representations. It also provided insight into the most salient issues that residents consider when contemplating the impact of an event.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Tourism and Hotel Management
Griffith Business School
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Cooke, Melanie. "The synoptic- and planetary-scale environments associated with significant 1000-hPa geostrophic wind events along the Beaufort Sea coast." Thesis, McGill University, 2010. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=86997.

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The substantial interannual variability and the observed warming trend of the Beaufort Sea region are important motivators for the study of regional climate and weather there. In an attempt to further our understanding of strong wind events, which can drive sea ice dynamics and storm surges, their characteristic environments at the synoptic and planetary scales are defined and analysed using global reanalysis data. A dependency on an enhanced or suppressed Aleutian low is found. This produces either a strong southeasterly or northwesterly 1000-hPa geostrophic wind event. The characteristic mid-tropospheric patterns for these two distinct event types show similarities to the positive and negative Pacific/North American teleconnection patterns, but their correlations have yet to be assessed.
L'étude du climat régional et du météorologie du Mer Beaufort est motivée par son variabilité interannuelle important et par la réchauffement qui y est observée. En essayant de comprendre les évenements à vents forts, qui peuvent forcer les dynamiques du glace marine et les ondes tempêtes, leurs environnements caractéristiques aux échelles synoptiques et planétaires sont définies et analysées en utilisant la donnée globale réanalysée. Une dépendance sur une dépression Aleutienne augmentée ou diminuée est trouvée. Ca produit un évenement à vents géostrophiques forts à 1000-hPa soit du soud-est soit du nord-ouest. La modèle caractéristique du mi-troposphère pour ces deux types d'évenements distincts démontrent des similarités aux modèles Pacifique/Nord-Américain positive et negative, mais leurs corrélations ont besoin d'être évaluées.

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Bovy, Kristine M. "Effects of human hunting, climate change and tectonic events on waterbirds along the Pacific Northwest coast during the late Holocene /." Thesis, Connect to this title online; UW restricted, 2005. http://hdl.handle.net/1773/6548.

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González, Hunt Ricardo M. "Boom-to-bust. The scallop (Argopecten purpuratus) fishery in the Pisco-Paracas region, southern Peruvian coast." Pontificia Universidad Católica del Perú. Centro de Investigación en Geografía Aplicada, 2013. http://repositorio.pucp.edu.pe/index/handle/123456789/119750.

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This paper examines scallop (Argopecten purpuratus) booms experienced in the Pisco-Paracas Region of southern Peru, triggered by the 1982-1983 and the 1997-1998 mega-El Niño Southern Oscillation (ENSO) events.The quiet fishing ports have been transformed by these booms, which have attracted outside stakeholders transforming the local society. Government institutions in their role as resource managers and environmental stewards have attempted to control access to a region that until recently contained the only marine protected area of Peru.This situation has led to rapid growth in the scallop industry, the overexploitation and depletion of the shellfish, creating a sustainability crisis. Furthermore, this paper examines contradictions and relationships across local, regional, national, and international scales.
Este trabajo examina los ciclos de expansión (boom) de la explotación de la concha de abanico (Argopecten purpuratus) observados en la región Pisco-Paracas del sur del Perú, resultantes de los fenómenos El Niño de 1982-1983 y 1997-1998.Los apacibles puertos de pesca han sido transformados por estos booms productivos que han atraído actores externos y han generado un impacto en la sociedad local. Las instituciones gubernamentales, en su papel de administradores de recursos y protectores del medio ambiente, han tratado de controlar el acceso a una región que hasta hace poco contenía la única área marina protegida del Perú.Esta situación ha producido un rápido crecimiento de la industria de la concha de abanico, su sobreexplotación y el agotamiento de dicho recurso, y ha producido una crisis de sostenibilidad. Asimismo, este trabajo examina las contradicciones y las relaciones entre las escalas local, regional, nacional e internacional.

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Engel, Max [Verfasser], Helmut [Akademischer Betreuer] Brückner, Frank [Akademischer Betreuer] Schäbitz, and Christophe [Akademischer Betreuer] Morhange. "The chronology of prehistoric high-energy wave events (tropical cyclones, tsunamis) in the southern Caribbean and their impact on coastal geo-ecosystems : a case study from Bonaire (Leeward Antilles) / Max Engel. Gutachter: Helmut Brückner ; Frank Schäbitz ; Christophe Morhange." Köln : Universitäts- und Stadtbibliothek Köln, 2012. http://d-nb.info/1038227496/34.

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Swanepoel, Lehahn Searle. "Positioning in Somali narratives in the Saldanha bay municipality area on the west coast of South Africa." Thesis, Stellenbosch : Stellenbosch University, 2011. http://hdl.handle.net/10019.1/17879.

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Thesis (MPhil )--Stellenbosch University, 2011.
ENGLISH ABSTRACT: This study is interested in discourses of displacement in which migrants articulate the experience of seeking improved life chances in a community considerably removed from their place of origin. Not only physical and environmental distance, but also distance related to cultural, linguistic and religious differences distinguish the (im)migrants from the local indigenous population, which is already a culturally and linguistically diverse community. This study investigates how histories of displacement and experiences of alienation or integration may be discursively managed among a group of young Somali males aged between 15 and 35 who entered South Africa in their late teens or early twenties. Specifically, this thesis considers how young Somali men who relocated to a rural Western Cape town and make a living through trading, present themselves in English-language narratives elicited during informal interviews. The study was conducted in Vredenburg, the administrative centre and economic hub of the Saldanha Bay Municipal area on the West Coast of South Africa. The data for the study was collected by means of audio recorded interviews. To supplement this data and gain more perspective on the situatedness of the discourses, the researcher further relied on field notes as well as additional informal conversations with the participants. The data was collected over a period of five months in 2007. To analyse the data, the researcher draws on the theoretical frameworks of Labov's structural analysis of narratives and Wodak and Reisigl's (2001) discourse-historical approach, and Bamberg's (1997) narrative constructivist perspective. The research aims to determine (i) how the narrators construct themselves in their narratives, and (ii) how speakers position themselves towards the content of their narratives, and towards their actual and imagined audiences. This study shows that displacement brings about new contexts characterised by uncertainty, conflict and inequalities, and this influences the way narrators orient themselves. The Somali narrators, in interviews conducted in English with a community outsider, position themselves as displaced and marginalised. During their narratives, the participants used several linguistic strategies to present themselves in various ways to actual or imagined audiences, which lead to negative otherpresentation and positive self-presentation and construction of in-group and out-group membership.
AFRIKAANSE OPSOMMING: Hierdie studie fokus op diskoerse van ontworteling waarin migrante hul ervaring verwoord van ’n soeke na beter lewensgeleenthede in ’n gemeenskap ver verwyderd van hul plek van herkoms. Buiten vir die fisiese en omgewingsafstand, is daar ook afstand daargestel deur kulturele, linguistiese en godsdiensverskille, wat die (im)migrante onderskei van die plaaslike bevolking – op sigself ’n kultureel en linguisties diverse gemeenskap. Hierdie studie doen ondersoek na hoe geskiedenisverhale oor ontworteling en ervarings van vervreemding of integrasie diskursief bestuur kan word binne ’n groep jong Somaliese mans van 15 tot 35 jaar wat Suid-Afrika in hul laat tienerjare of vroeë twintigerjare binnegekom het. Die tesis fokus spesifiek op hoe jong Somaliese mans wat na ’n plattelandse Wes-Kaapse dorp migreer het en ’n handelsbestaan voer, hulself voorstel in Engelstalige narratiewe wat ontlok is tydens informele onderhoude. Die studie is gedoen in Vredenburg, die administratiewe en ekonomiese kern van die Saldanhabaai Munisipale Area aan die Weskus van Suid-Afrika. Die data vir die studie is ingesamel deur middel van klankopnames van onderhoude. Ten einde dié data aan te vul en meer perspektief te verkry ten opsigte van die plasing van die diskoerse, het die navorser verder gesteun op veldnotas sowel as bykomende informele gesprekke met die deelnemers. Die data is oor ’n tydperk van vyf maande in 2007 versamel. In die ontleding van die data maak die navorser gebruik van die teoretiese raamwerke van Labov se strukturele analise van narratiewe en Wodak en Reisigl (2001) se diskoers-historiese benadering, asook Bamberg (1997) se narratief-konstruktivistiese perspektief. Die navorsing het ten doel om vas te stel (i) hoe die vertellers hulself in hul narratiewe konstrueer, en (ii) hoe sprekers hulself posisioneer ten opsigte van die inhoud van hul narratiewe en ten opsigte van hul werklike en denkbeeldige gehore. Hierdie studie toon dat ontworteling nuwe kontekste skep wat gekenmerk word deur onsekerheid, konflik en ongelykhede en ’n invloed het op die wyse waarop vertellers hulself orienteer. Tydens onderhoude met ’n gemeenskapsbuitestaander, uitgevoer in Engels, posisioneer die Somaliese vertellers hulself as ontwortel en gemarginaliseer. In hul narratiewe gebruik hulle verskeie linguistiese strategieë om hulself op verskillende maniere voor te stel aan werklike en denkbeeldige gehore wat lei tot ’n negatiewe voorstelling van die Ander, ’n positiewe voorstelling van die Self en die daarstelling van binne- en buite-groep lidmaatskap.

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Suliman, Tammam [Verfasser], Uta [Gutachter] Berger, der Maaten-Theunissen Mareike [Gutachter] van, and Wael [Gutachter] Ali. "Understanding the dynamics of even-aged stands of Brutia pine (Pinus brutia Ten.) in the coastal region of Syria based on a distance-independent individual-tree growth model / Tammam Suliman ; Gutachter: Uta Berger, Mareike van der Maaten-Theunissen, Wael Ali." Dresden : Technische Universität Dresden, 2020. http://d-nb.info/1227833695/34.

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Alsarawi, Noura. "Design of Low Impact Development and Green Infrastructure at Flood Prone Areas in the City of Miami Beach, FLORIDA, USA." FIU Digital Commons, 2018. https://digitalcommons.fiu.edu/etd/3739.

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This thesis investigates the effectiveness of Low Impact Development Infrastructure (LIDI) and Green Infrastructure (GI) in reducing flooding resulting from heavy rainfall events and sea-level rise, and in improving stormwater quality in the City of Miami Beach (CMB). InfoSWMM was used to simulate the 5, 10, and 100-year, 24-hour storm events, total suspended solids (TSS), biochemical oxygen demand (BOD), and chemical oxygen demand (COD) loadings, and in evaluating the potential of selected LIDI and GI solutions in North Shore neighborhood. Post-development results revealed a decrease of 48%, 46%, and 39% in runoff, a decrease of 57%, 60%, and 62% in TSS, a decrease of 82%, 82%, and 84% in BOD, and a decrease of 69%, 69%, and 70% in COD loadings. SWMM 5.1 was also used to simulate the king tide effect in a cross section in Indian Creek Drive. The proposed design simulations successfully demonstrated the potential to control flooding, showing that innovative technologies offer the city opportunities to cope with climate impacts. This study should be most helpful to the CMB to support its management of flooding under any adaptation scenarios that may possibly result from climate changes. Flooding could be again caused as a result of changes in inland flooding from precipitation patterns or from sea-level rise or both.

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Dissertations / Theses on the topic 'Coastal event'

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