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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
321

The development and evaluation of a maturity assessment tool for Church Resource Ministries

Strawsburg, Brent L. January 1999 (has links)
Thesis (D. Min.)--Dallas Theological Seminary, 1999. / Appendix A-D not numbered. Includes abstract. Includes bibliographical references (leaves 218-232).
322

Developing a biblical leadership and church government structure for Oceanside Community Church

Rowland, Charles Ross. January 2005 (has links)
Thesis (D. Min.)--Mid-America Baptist Theological Seminary, 2005. / Abstract. Includes bibliographical references (leaves 187-199).
323

Modélisation des évolutions à long terme du trait de côte et de l'érosion côtière / Modeling long term shoreline evolution and coastal erosion

Tran, Hai Yen 20 September 2018 (has links)
Cette recherche porte sur des modélisation des évolutions à long terme du trait de côtes, dans laquelle on propose un modèle qui combine à la fois une contribution des processus cross-shore et celle de processus longshore pour améliorer les capacités prédictives. Le modèle cross-shore de Splinter et al. (2014) est ré-implémenté dans un but de comparaison avec le modèle combiné. Nous présentons un modèle longshore simple basé sur une approche "one-line" moyenne dans le temps. L’analyse de ce modèle longshore donne l’orientation de la plage d’équilibre par rapport à l’orientation de l’onde incidente. Il révèle également qu’une partie de la variabilité saisonnière des positions du trait de côte est due au transport par la dérive littorale. Par conséquent, la contribution longshore du modèle combiné améliore les capacités prédictives. Les prédictions du modèle sont confrontées à des mesures des positions du trait de côte de différents types de plages, comme celles de Truc Vert, en France et des plages en baie avec courbure de Narrabeen, en Australie et de Nha Trang, au Vietnam.Cette thèse offre deux nouvelles contributions précieuses. Le premier est un modèle longshore simple et l’orientation de la plage d’équilibre. Le second est un modèle combiné de long-shore et cross-shore. / This research focuses on the long-term shoreline evolution modeling, in which a combined model comprising the shoreline change due to longshore drift in a cross-shore shoreline model is proposed to improve the predictive skills of the long-term shoreline response. The cross-shore shoreline model of cite{splinter2014} is re-implemented for a purpose of comprehensive comparison with the combined model. A simplified longshore shoreline model is developed on the basis of the one-line type approach. The analysis of this longshore model yields the equilibrium beach orientation in relation to the incident wave orientation. It also reveals that part of seasonal shoreline position variability is due to the longshore transport. Therefore, the presence of the longshore model in the combined model clearly improves the model skills. The shoreline evolution models are calibrated with data from different beach types, such as a straight open beach shoreline of Truc Vert, France and embayed beach shoreline of Narrabeen, Australia and Nha Trang, Vietnam.This thesis gives two valuable contributions. The first one is a simplified longshore model and the equilibrium beach orientation. The second one is a combined longshore cross-shore phenomenological model.
324

Identificação de áreas de sedimentos compatíveis na Plataforma Continental interna para recuperação de praias entre as cidades de Niterói e Macaé– RJ

Oliveira, Julio Fernandes de January 2012 (has links)
A faixa urbanizada da orla na costa sul – oriental e leste do Estado do Rio de Janeiro sofre constantemente com a destruição de calçadões, ruas, muros e casas em eventos oceanográficos extremos. Essas construções, na maior parte dos casos estão localizadas muito próximas ao limite com a praia, dentro da faixa de não edificação prevista no Projeto Orla do Ministério do Meio Ambiente. A região apresenta forte crescimento populacional com principais atividades econômicas associadas à exploração de petróleo nas cidades de Macaé e Rio das Ostras, ao turismo da Região dos Lagos, além do centro urbano de Niterói já consolidado. A identificação de jazidas de material semelhante ao original para recuperação de praias como opção de mitigação, representa uma alternativa para manter a função de proteção exercida pelas mesmas e de seu uso para o lazer. Nesse sentido, este estudo tem como objetivo analisar a compatibilidade de sedimentos superficiais da plataforma continental interna com as areias de praias urbanas, situadas entre as cidades de Niterói e Macaé – RJ, através da comparação de parâmetros estatísticos da distribuição granulométrica das areias desses dois ambientes. Para a caracterização sedimentar das praias alvo, foram coletadas amostras da face praial de 16 praias situadas nos principais núcleos urbanos deste segmento do litoral fluminense. Os dados granulométricos dos sedimentos superficiais da antepraia e plataforma continental interna entre Niterói e Macaé são secundários, de campanhas oceanográficas pretéritas. Tais dados foram filtrados e digitalizados, somando um total de aproximadamente 1200 pontos de coleta que vão desde a barra leste da Baia da Guanabara até a Restinga de Jurubatiba. Onze áreas granulometricamente compatível com as diferentes praias da região de estudo foram identificadas próximo à isóbata de -20 m ao largo da costa de Niterói e Maricá, de Cabo Frio e Búzios e entre Rio das Ostras e Macaé, representando potenciais estoques de sedimento para utilização em projetos de recuperação dessas praias. / The urbanized coastline of east and south-east littoral of the state of Rio de Janeiro suffers constantly with the destruction of houses, walls and streets in extreme oceanographic events. These constructions, in most cases are located very close to the limit with the beach, inside of the range of no building suggest by Projeto Orla – Ministry of Environment. This region has strong population growth with major economic activities associated with oil exploration in the city of Macae and Rio das Ostras, industry of tourism in Lakes Region and the urban center of Niteroi already consolidated. The identification of sand deposits with similar granulometric characteristics to the native material to nourishment project as a mitigation option, represented an alternative to maintain the protective function of the beach and use for recreation. The objective of this study is analyze the compatibility of surface sediments of the inner continental shelf and sands of urban beaches, located between the cities of Niteroi and Macae – RJ, through of comparison the statistical parameters of size distribution of the sands of these two environments. For the characterization of sedimentary beaches were sampled from the beach face of 16 beaches located in the major urban centers of this segment of the coastline of Rio de Janeiro’s state. The granulometric data of surface sediments of the inner continental shelf between Niteroi an Macae are secondary from preterits oceanographic campaigns. These datas were filtered and digitized with a total of approximately 1200 collection points ranging from east bar of Guanabara Bay to the Restinga de Jurubatiba. Eleven areas granulometrically compatible with the different beaches were identified near the -20 meters isobaths near the coast of Niteroi and Marica, Cabo Frio and Buzios and between Rio das Ostras and Macae, representing a potential borrow areas for use in nourishment projects in this region.
325

Historic Preservation of Pacific Northwest Beach Houses: A Study of Beach Houses along Tillamook County's Coast / Study of Beach Houses along Tillamook County's Coast

Donovan-Boyd, Adrienne K. 06 1900 (has links)
xiii, 207 p. : ill. (some col.), maps. A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. / Preserving Pacific Northwest historic beach houses in coastal communities can often be a daunting task due to the complexities that arise when combining preservation, planning, development, and climatic hardships. Using Tillamook County's coastline as the study area, this thesis explores the historical development of Tillamook County's structures and the current barriers that exist when trying to preserve them. Historical discussions include the development of transportation routes, recreational amenities, and the evolution of coastal construction materials, along with historic local and regional planning decisions that helped shaped towns along Tillamook County's coastline. Following this historical discussion, current preservation challenges will be discussed as well as the recommendations for preserving and maintaining vernacular coastal beach houses of the Pacific Northwest. / Committee in Charge: Leland Roth, Chair; Donald Peting
326

Uso e ocupação do solo o futuro da Praia de Iracema / Use and occupation of the land the future of the Beach of the Future

Abreu Júnior, Pedro Itamar de January 2005 (has links)
ABREU JÚNIOR, Pedro Itamar de. Uso e ocupação do solo o futuro da Praia de Iracema. 2005. 238 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Pró-Reitoria de Pesquisa e Pós-Graduação, Programa Regional de Pós-Graduação em Desenvolvimento e Meio Ambiente - PRODEMA, Fortaleza-CE, 2005 / Submitted by Nádja Goes (nmoraissoares@gmail.com) on 2016-04-08T15:00:35Z No. of bitstreams: 1 2005_dis_piabreujúnior.pdf: 5432876 bytes, checksum: f384837b7d648e174af9c036ece663bd (MD5) / Approved for entry into archive by Nádja Goes(nmoraissoares@gmail.com) on 2016-04-08T15:00:54Z (GMT) No. of bitstreams: 1 2005_dis_piabreujúnior.pdf: 5432876 bytes, checksum: f384837b7d648e174af9c036ece663bd (MD5) / Made available in DSpace on 2016-04-08T15:00:54Z (GMT). No. of bitstreams: 1 2005_dis_piabreujúnior.pdf: 5432876 bytes, checksum: f384837b7d648e174af9c036ece663bd (MD5) Previous issue date: 2005 / This work investigates land use and occupation alone the 6km of Future beach, at the east seaside of Fortaleza-Ceará, limited by the sea (Atlantic ocean), at one side; the road Trajano de Medeiros, the road Ismael Pordéus and the estuary of Cocó river, at Caça e Pesca beach.In this work we tried an historical account of the place as an attempt to better understand its present situation, aiming at amusing the reasons why the neighbor suburbs show much denser standards of land use and occupation than the Future beach. Interviews were made with the main agents within the area, from the irregular users to hotel owners. By making use of research concerning published news on local newspapers, it was possible to get data covering the last 40 years of the seaside place, as there is very few available literature or academic work related to it. The search for an interdisciplinary approach has adapted throughout this work, using systematic methodology, basically as the work, using the systemic methodology, basically as an attempt to get answers to natural environmental impacts, and use the dialectic methodology in order to formulate hypothesis to human environmental impacts, which together are determinant to the actual pattern of land use an occupation at Future beach. This research also aims to provide means for understanding of the area under study as well as being useful as tool for others to work with, where as all particular characteristics of the place can be taken into account and the notion of sustainable development be always sought. This research was made possible with the support of the national council for research and development (CNpq) and the Federal University of Ceará / O presente trabalho investiga o Uso e Ocupação do Solo nos 6 km da Praia do Futuro, no litoral leste de Fortaleza-Ceará, limitada pelo recorte entre a faixa de praia, a rua Trajano de Medeiros, a rua Ismael Pordéus e o estuário do rio Cocó, na praia do Caça e Pesca. Neste trabalho buscou-se um resgate histórico do local como tentativa de melhor compreensão da situação presente, objetivando analisar os motivos dos bairros contíguos à área de estudo apresentarem um padrão quanto aos Usos e Ocupações do Solo mais intensos em comparação com os da Praia do Futuro. Foram feitas entrevistas com os agentes principais da área, desde os ocupantes irregulares das dunas, até proprietários de hotéis. Utilizando-se em uma maior intensidade de pesquisas hemerográficas, foi possível obter dados elucidativos dos últimos 40 anos dessa faixa de praia do litoral Cearense, já que pouco material é disponível na literatura ou trabalhos acadêmicos. A busca da interdisciplinaridade permeou todo o trabalho, utilizando-se de uma metodologia sistêmica, basicamente como tentativa de obter respostas aos impactos ambientais naturais e a utilização da metodologia dialética como tentativa de propiciar formulações de hipóteses para os impactos ambientais antrópicos, que juntas são determinantes para a atual prática do Uso e Ocupação do Solo na Praia do Futuro. Essa pesquisa objetiva propiciar caminhos para o entendimento da área em questão e servir de instrumento outros para trabalhos técnicos, onde leve-se em conta todas as peculiaridades do local e a noção do Desenvolvimento Sustentável seja sempre buscada. Esta pesquisa teve apoio financeiro do Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPQ) e apoio técnico da Universidade Federal do Ceará.
327

Áreas potenciais à exploração de granulados marinhos siliciclásticos para a recuperação artificial de praias na plataforma continental interna adjacente ao Porto do Recife-PE

Andrade, Carla Danielle Pereira de January 2013 (has links)
O mapeamento da Plataforma Continental Interna visando localização, qualificação e quantificação das reservas de material litoclásticos marinho possui poucos trabalhos relacionados. O Estado de Pernambuco sofre com erosões ao longo de todo seu litoral, e principalmente junto às cidades de Recife e Olinda. Assim, este estudo contribui tanto para o conhecimento da sedimentologia da plataforma continental interna adjacente ao Porto do Recife e à Praia dos Milagres em Olinda, quanto para a execução de futuras intervenções na recuperação das praias da região. Portanto, com objetivo de identificar áreas com concentrações de granulados litoclásticos marinhos compatíveis com especificações necessárias à regeneração de praias, foram analisadas 36 amostras, que foram coletadas ao longo de seis perfis equidistantes em 1 km, perpendiculares à linha de costa na plataforma interna do Porto do Recife. Em laboratório foram realizadas análises granulométricas e o estudo composicional de todas as amostras. Os resultados granulométricos mostram a predominância de sedimentos mal selecionados, ocorrendo classes variadas de tamanho entre seixo pequeno (8 mm) e lama (< que 0,062 mm), com predominância da fração areia grossa. A análise composicional revelou uma hegemonia de carbonatos marinhos. Os dados obtidos apresentam uma redução do suprimento sedimentar terrígeno local. Também de acordo com os resultados obtidos no presente estudo, a plataforma continental interna adjacente ao Porto do Recife e à praia dos Milagres em Olinda-PE, é essencialmente recoberta por areias biogênicas mal selecionadas, oriundas da morte e fragmentação dos organismos componentes dos recifes coralíneos e algálicos que ocorrem na plataforma continental interna. Dessa forma, esta área não possui material siliciclástico suficiente para ser utilizado na exploração mineral para recuperação artificial de praias no Estado de Pernambuco. / There are few studies that map the Internal Continental Platform referring to localization, qualification and quantification of reserves of litoclastic marine material. The Brazilian state Pernambuco suffers from erosions along the whole coast and particularly in areas close to the cities of Recife and Olinda. This study offers new knowledge about the sedimentology of the internal continental platform adjacent to the harbor of Recife and the Beach Milagres in Olinda. Furthermore, it points out measures that can be used to recover regional beaches. Along 6 profiles with a distance of 1km and perpendicular to the coast line at the internal platform of the harbor of Recife, 36 samples were collected and analyzed. Thus, areas with concentrations of litoclastic marine aggregates with the necessary characteristics for the recovery of the beaches were identified. A laboratory was used for granulometry and a compositional study of all samples. The granulometric results show mainly badly selected sediments. There are different sizes from small pebbles (8 mm) to mud (< than 0,062 mm), predominantly coarse sand fraction. The compositional analysis reveals hegemony of marine carbonates. Thus the obtained data indicates a reduction of local terrigenous sedimentary supply. This is probably due to the fact that the selected area is undergoing an initial transgressive process. Also in accordance with the obtained results of this study, the internal continental platform adjacent to the harbor of Recife and the Beach Milagres in Olinda, Pernambuco, is mainly covered by badly selected biogenic sand which has its origin in the death and fragmentation of components of the coral reef of the internal continental platform. As a result the area is not indicated to mineral exploration for the artificial recovery of the beaches in the state of Pernambuco.
328

A barreira costeira holocênica e suas relações com a morfodinâmica praial no Estado do Rio Grande do Sul, Brasil

Reichow, Camila January 2018 (has links)
A análise dos parâmetros morfométricos publicados buscou relacionar o comportamento morfodinâmico praial com o da barreira costeira holocênica no estado do Rio Grande do Sul (RS), para estabelecer de que maneira estes ambientes estão relacionados. Foram analisados os dados de 31 praias, de Torres ao Chuí, possibilitando uma revisão e reavaliação dos estágios morfodinâmicos, com a compartimentação destes locais em cinco grupos, baseados em sua morfodinâmica e mobilidade praial. O grupo 1 é composto pelas praias intermediárias de mobilidade moderada à alta, que estão em sua maioria localizadas no litoral médio do RS correspondente a barreira agradacional, com alto desenvolvimento de campos de dunas transgressivas e dunas frontais, e estão também associadas às praias com característica retrogradante da barreira, porção sul da barreira agradacional. O grupo 2 compõe as praias dissipativas, com estágio intermediário ocorrendo de maneira secundária, de moderada à alta mobilidade, associadas a barreira progradante do litoral norte. Este setor apesar de apresentar alto potencial de transporte sedimentar por ventos e por ondas não apresenta campos de dunas bem desenvolvidos, onde o aporte sedimentar favorece a progradação costeira. O grupo 3 é formado por praias intermediárias de baixa mobilidade, associadas à porção norte da barreira agradacional e às praias do litoral sul que representam a transição entre a barreira progradante e retrogradante. No litoral médio a associação da baixa mobilidade praial com a alta capacidade de transporte e disponibilidade sedimentar, resultante do transporte sedimentar pelo vento no sentido continental, permitiu o desenvolvimento de grandes campos de dunas transgressivos e de dunas frontais. O grupo 4 é constituído por praias dissipativas e secundariamente intermediárias, de baixa mobilidade, da barreira progradante do litoral sul, que não desenvolveu vastos campos de dunas, semelhante ao que ocorre na barreira progradante ao norte. O grupo 5 é formado por duas praias diferenciadas, onde o estágio intermediário predomina e o refletivo ocorre eventualmente no verão, e estão localizadas em barreiras retrogradantes. As praias dissipativas são responsáveis por remobilizar o maior volume sedimentar da antepraia ao ambiente praial, onde integra o processo de progradação costeira. A porção da barreira agradacional, responsável pelas maiores dunas frontais, apresenta a menor mobilidade, sendo que conforme sua mobilidade é aumentada em direção ao sul, os maiores campos de dunas transgressivas ocorrem. Os estágios intermediários possuem energia suficiente para transportar sedimentos da antepraia para a praia, enquanto que a formação ou não das dunas é influenciada pelo potencial de transporte do vento NE e pela orientação da linha de costa com relação a este vento. As barreiras retrogradantes estão associadas a estágios intermediários de mobilidade variável, sendo que os dois focos erosivos do estado estão associados à alta mobilidade, o qual deixa estes ambientes susceptíveis aos episódios de erosão durante a passagem de eventos de tempestades. Assim, o caráter erosivo da barreira pode estar associado tanto com a energia de ondas, quanto com uma antepraia irregular e um déficit sedimentar, que acarreta em variações na morfodinâmica praial. / The analysis of the morphometric parameters of the published works about beach morphodynamics in the State of Rio Grande do Sul had the objective to relate the morphodynamic behavior of the beach with the holocene coastal barrier, in order to establish how these environments are related. The data of 31 beaches were analyzed, allowing a review and reevaluation of the morphodynamic stages, with the compartmentalization of these sites in five groups, based on their morphodynamics and beach mobility. Group 1 is composed of intermediate beaches with moderate to high mobility, which are located in the middle coast corresponding to the aggradational barrier, with high development of transgressive dunes and foredunes, and, associated too with the beaches with retrogradational characteristics of the barrier. Group 2 consists of dissipative beaches, with intermediate stage occurring in a secondary way, being these from moderate to high mobility, associated with the progradational barrier of the north coast. This sector, despite to present a high potential for sediment transport by winds and waves, does not have well development dunefields, where the sediment budget supports coastal progradation. Group 3 is formed by intermediate beaches of low mobility, associated with the northern portion of the aggradational barrier and the beaches of the south coast that represent the transition between the prograded and retrograded barrier. In the middle coast, the association of low beach mobility with high transport capacity and sedimentary availability, and the resulting of the sedimentary transport by wind onshore, allowed the development of large transgressive dunefields and foredunes. Group 4 consists of dissipative and secondarily intermediate beaches, with low mobility, of the progradational barrier of the south coast, which, similar to what occurs in the progradational barrier of the north, did not develop largest dune fields. Group 5 is formed by two beaches with peculiar characteristics, where the intermediate stage predominates and the reflective occurs eventually in the summer, associated with the retrograded barrier. The dissipative beaches are responsible for remobilizing highs sediments volumes of the shoreface and provide to the beach environment, where, in this case, it is converted into coastal progradation. The portion of the aggradational barrier responsible for the largest frontal dunes presents the smaller mobility, and as its mobility is increased towards the south, the largest transgressive dunefields in the state occurs. The intermediate stages have enough energy to carry sediments from the shoreface to the beach, while the formation of the dunes is influenced by the transport potential of the NE wind and by the orientation of the coastline in relation to this wind. Retrograded barriers are associated to intermediary stages of variable mobility, and the two erosive hotspots of the state are associated with high mobility, which turns these environments susceptible to erosion episodes during the passing of storm events. Thus, the erosive character of the barrier may be associated with both wave energy and an irregular shoreface and a negative sediment budget, which leads to variations in beach morphodynamics.
329

Geomorfologia e arquitetura deposicional de uma planície de cordões litorâneos lacustre, litoral norte do RS - Brasil

Bitencourt, Volney Junior Borges January 2015 (has links)
Cordões litorâneos regressivos arenosos do tipo praia (beach ridge) e do tipo duna frontal (foredune ridge) são feições morfológicas comuns em costas deposicionais com abundância de sedimento. No presente estudo, a morfologia superficial, estratigrafia e a origem de uma planície de cordões ocorrentes na Lagoa dos Quadros, litoral norte do Rio Grande do Sul, são investigadas. Abordagens em superfície através de análises de fotografia aéreas, análises de imagens de satélite e altimetria de detalhe, em junção com dados em subsuperfície oriundos de perfilagens geofísica com uso de GPR e dados sedimentológicos provenientes de testemunhos de sondagens rasos proporcionaram elucidar as fáceis que compõem a arquitetura deposicional, bem como especificar as características geométricas superficiais dos cordões. Datações por 14C permitiram estimar o estágio do início do desenvolvimento da planície de cordões, e a modelagem de ondas e análise de ventos propiciaram inferir as condições fluidodinâmicas envolvidas em sua gênese. A planície de cordões é composta por cordões de praia e cordões de duna frontal, ou seja, uma barreira complexa. Esses cordões são o resultado do desenvolvimento de uma sequência regressiva sobre uma fácies basal de fundo (lagunar). Essa sequência regressiva é composta por depósitos de antepraia, de pós-praia/face de praia, dunas frontais e depósitos de leque de sobrelavagem. A fácies basal de fundo lagunar registra a fase de agradação e progradação da fácies de fundo lagunar do sistema lacustre, ocorrida entre 7047 ± 197 ka e 6230 ± 122 ka. A planície é composta por 20 cordões contínuos e semi-contínuos, de baixa amplitude e espaçados de 5 a 50 m. A migração de campos de dunas transgressivos da barreira de Curumim para dentro da lagoa (entre 7,1 e 5,5 ka) podem ter sido uma importante fonte de areia para a formação da planície de cordões litorâneos regressivos da margem NE da Lagoa dos Quadros. / Beach ridges and foredune ridges are morphological elements largely present in depositional coasts with abundant sediment supply. In this study, the morphology, the stratigraphy and genesis of a strandplain (sand ridge plain) developed at the Quadros lagoon, northern littoral of Rio Grande do Sul, are studied. Photographic surveys, analysis of satellite imagery and topographic surveying plus geophysical data collected with GPR and sedimentological data from drill holes allowed elucidate the facies that make up the depositional architecture and specify the surface geometric characteristics of the ridges. Was possible to estimate the stage of development of the strandplain by 14C dating, and the modeling of waves and analysis of winds pattern have led to infer the fluid dynamic conditions involved in its genesis. The strandplain comprises beach ridges and foredune ridges, which makes a complex barrier. These ridges are results of a regressive sequence developed on a lagoon bottom basal facies. The regressive sequence comprises deposits of shoreface, deposits of beachface/ backshore, foredunes and washover fan. The lagoon bottom basal facies records the aggradation and progradation phases of the lagoon bottom facies of the lagoon system occurred between 7047 ± 197 ka and 6230 ± 122 ka. The strandplain comprises 20 continuous and semi-continuous ridges, low amplitude and spaced 5-50 m. The migration of transgressive dune fields of Curumim barrier to inside the lagoon (between 7.1 and 5.5 ka) may have been an important source of sand to form the strandplain of NE margin of Quadros Lagoon.
330

Rip Current Formation and Beach Safety Implications for Several U.S. Atlantic Coast Beach Areas

Fallon, Kathleen Michelle 15 May 2017 (has links)
This dissertation combines seemingly different studies, which work together to describe the physical characteristics of rip current development and associated social implications at several locations. These fast-moving, concentrated flows of water travel offshore and can be found on any beach with sufficient wave action. Any event of increased wave steepness will erode a large quantity of sediment from the beach. The material deposited offshore eventually makes its way back; during this process, ocean water becomes trapped behind a shore-attached bar resulting in a ridge-and-runnel. These formations are seen at East Hampton, where rip-like currents form as concentrated water drains from the runnel through a breach in the ridge. Camera images from 2010-2016 captured ridge-and-runnel formations and the ensuing currents. These newly described rips behave similarly to bar-gaps; however, they are not directly related to wave action. Coastal scientists consider rip currents to be the number one hazard at most beaches. In Palm Beach County, two traditional rip types were studied: bar-gap and structurally-controlled. Lifeguard incident reports from 2011-2016 were used to correlate wind speeds and wave heights to rip related rescues at three beaches. This research was undertaken in an effort to determine under what conditions most beachgoers become caught in this hazard. Rip currents were seen to be the most dangerous to bathers on days with moderate wind and wave activity. The same beach states that lead to the strongest rips also tend to keep beachgoers from entering the ocean. A social survey at Miami Beach, from 2011 to 2012, quantified beachgoer’s rip knowledge and their recognition of hazards. A significant portion of the respondents showed insufficient knowledge, which indicated they are at-risk of being caught or drowning in a rip current. Frequent exposure to the beach, maturation, and residency were identified as the main contributors to one’s literacy whereas education was the only variable that influenced a beachgoer’s visual recognition of hazard. The information gathered by these surveys can aid in creating better rip current awareness campaigns targeted to demographics that were determined as the most at-risk. An understanding of the physical and social science of rip currents can mitigate the impact of these beach hazards.

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