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Comprehensive sediment budgets are compiled for a series of pocket shingle beaches in West Dorset backed by massive soft cliffs that degrade in a rapid and complex manner. Studies involve the identification and quantification of sediment (primarily shingle) inputs, transfers, storage and outputs within terrestrial and marine subsystem components. Results are unified within budget and flow models and applied to tackle questions of coastal evolution and management. Research involved mapping and sampling of the ground forming materials in terms of their beach forming potential. Cliff landsliding and recession are analysed using comparisons of historical maps, aerial photos and documentary evidence. A method of quantifying the release, throughput and supply to the beaches of various sediment grades from the eroding cliffs is presented. The volumes and types of sediment at the beach and in the inshore zone are investigated by various profile, intertidal, and offshore surveys. Detailed sampling and sediment analysis of the beaches is undertaken to elucidate beach drift and for attrition assessments through comparisons with cliff inputs. Shingle tracing experiments using aluminium tracers are conducted to study transport and sorting at two contrasting sites over a full spectrum of wave energy conditions. Validated littoral drift volumes and original wave power relationships are developed. Information is compiled to produce budget models for the main beaches. Complex long established links are demonstrated between eroding cliff sources and the shingle beaches that they supply. Chesil Beach is identified as the ultimate shingle sink suggesting that it is not entirely a product of the Holocene transgression as often envisioned, but a component of a Lyme Bay process system and open periodically to inputs of shingle from the west. Adverse impacts arising from various human interventions are highlighted using the models.

Displacement has continuously plagued communities for as long as society has existed. The refugee in response to climate change creates a relatively new facet in approaching relocation of a community due to circumstances that negate self-infliction and are product of irreversible external factors. As the coastal periphery of our nation continues to sink at nauseating rates, with it takes homes, green space, agriculture, and economic practices. In addition to a drastic alteration in the way of life, an emotional phenomenon of place attachment becomes dramatically exposed as mother nature strips a community of their native geography. Though proposals to relocate can be beneficial in the mere sense of avoiding the inevitable, the need to preserve a familiar landscape creates a set of design issues of architectural mimicry placed in differing context than its original intent. Structure is designed according to contextual parameters that aim to make ease of living and circulation. One must be aware of the nostalgia built form and its competition with a new set of parameters. Especially when reliance on urbanized economical growth and networking is introduced. This thesis takes a critical look at the approach and practicality of displacement and relocation, its relationship to the new breed of global climate change refugees, and its overall necessity in an age of vast technological advances. Architectural intervention will be investigated at the root of the problem rather than by proposition of dislocating geography based culture. In order to prevent further urbanization issues in respect to sprawl and social integration, what would it take, or start to look like, to keep a population at heir original disappearing settlement? The Isle de Jean Charles and the Biloxi-Chitimacha-Choctaw tribe will act as the specific case study in developing a resilient and sustainable architectural catalyst. / 0 / SPK / specialcollections@tulane.edu

FundaÃÃo de Amparo à Pesquisa do Estado do Cearà / O trabalho analisou a vulnerabilidade costeira em funÃÃo das alteraÃÃes morfosedimentares e dos galgamentos oceÃnicos (overtopping) impulsionados pelos eventos de alta energia (ressacas do mar) ocorridos na Praia dos DiÃrios (Fortaleza, CearÃ, Brasil). O litoral de Fortaleza à sazonalmente afetado por ressacas do mar que induzem rÃpidas mudanÃas na morfologia praial e provoca a destruiÃÃo do patrimÃnio edificado a retaguarda das praias, caso observado na Ãrea estudada, em que as ondas galgam a estrutura urbana limÃtrofe e atingem a avenida principal. Assim, à necessÃrio monitorar com alta frequÃncia os processos naturais que induzem alteraÃÃes no ambiente praial e provocam danos fiscos as estruturas urbanas. Desse modo, o mÃtodo de anÃlise consistiu na delimitaÃÃo de um transecto de aproximadamente 100 m de largura por 85 m de comprimento, onde os perfis de praia foram distribuÃdos com a equidistÃncia de 10 m, totalizando 11 perfis monitorados. AlÃm disso, foram avaliados os parÃmetros oceanogrÃficos â ondas (Hs, Tp, direÃÃo), marÃs (amplitude) e ventos (velocidade e direÃÃo). Essas variÃveis sÃo importantes para o cÃlculo de alcance mÃximo das ondas de ressaca do mar (run-up), bem como na determinaÃÃo do parÃmetro de Dean (Ω) e o parÃmetro de variaÃÃo relativa da marà (RTR) que foram utilizados na descriÃÃo da morfodinÃmica praial. Associado a esses procedimentos tambÃm foram coletadas amostras de sedimentos em situaÃÃes hidrodinÃmicas distintas. Para efeito de anÃlise comparativa foram utilizados resultados de 5 (cinco) experimentos de campo realizados em perÃodo de baixa e alta energia (com ondas de ressaca). Em condiÃÃes de baixa energia, a praia apresentou maior volume sedimentar resultando no desenvolvimento da berma e no incremento da declividade da face praial pela aÃÃo direta de ondas do tipo sea. Em alta energia, ondas do tipo swell atuaram na suavizaÃÃo da morfologia praial. A dinÃmica sedimentar na Praia dos DiÃrios nÃo apresentou considerÃveis alteraÃÃes ao longo dos perÃodos de alta e baixa energia. Tal fato està associado à baixa disponibilidade de material sedimentar grosso que fica retido ao largo do litoral. Os galgamentos provocaram danos na infraestrutura costeira e configurou a formaÃÃo de uma planÃcie lavada, potencializando a vulnerabilidade da Ãrea a inundaÃÃo. O conhecimento cientÃfico dos impactos das ressacas do mar e dos seus processos associados se mostrou como uma importante ferramenta para o manejo e o gerenciamento de litorais turÃsticos urbanos. / O trabalho analisou a vulnerabilidade Costeira los funcao das alteraÃÃes morfosedimentares e dos galgamentos OCEANICOS (galgamento) impulsionados Pelos eventos de Alta Energia (ressacas do Mar) ocorridos na Praia dos DiÃrios (Fortaleza, CearÃ, Brasil). O litoral de Fortaleza E sazonalmente afetado POR ressacas do Mar that induzem RÃpidas MudanÃas na Morfologia praial e provoca a DestruiÃÃo do PatrimÃnio edificado um DAS retaguarda Praias, Caso observado na Ãrea ESTUDADA, in that como Ondas galgam a Estrutura urbana limitrofe e atingem a Avenida Principal . ASSIM, E necessary monitorar com Alta FrequÃncia OS Processos Naturais that induzem alteraÃÃes no Ambiente praial e provocam Danos Fiscos como Estruturas Urbanas. Desse modo, o MÃtodo de AnÃlise consistiu na delimitaÃÃo de hum transecto de 100 m de Approssimato Largura POR 85 m de comprimento, Onde OS Perfis de praia were DistribuÃdos com uma equidistÃncia de 10 m, totalizando 11 Perfis monitorados. Disso de AlÃm, were avaliados OS ParÃmetros oceanogrÃficos - Ondas (Hs, Tp, DireÃÃo), MarÃs (amplitude) e ventos (Velocidade e DireÃÃo). Essas variÃveis SÃo IMPORTANTES Para O CÃlculo de Alcance MÃximo das Ondas de ressaca do Mar (run-up), Bem Como na determinaÃÃo do parametro de Dean (Ω) EO parametro de variaÃÃo Relativa da Marà (RTR) that were utilizados na DESCRIÃÃO da morfodinÃmica praial. Associado a sos Procedimentos also were coletadas Amostras de sedimentos los situations hidrodinÃmicas distintas. Para Efeito de AnÃlise Comparativa were utilizados Resultados de 5 (Cinco) Experimentos de Campo Realizados los PerÃodo de Baixa e Alta Energia (com Ondas de ressaca). Em condiÃÃes de Baixa Energia, a praia apresentou Maior volume de sedimentar resultando no Desenvolvimento da berma e sem incremento da declividade da cara praial Pela AÃÃo Direta de Ondas do mar Tipo. Em Alta Energia, Ondas do Tipo inchar atuaram na suavizaÃÃo da Morfologia praial. A DinÃmica sedimentar na Praia dos DiÃrios de: NÃo apresentou considerÃveis alteraÃÃes AO Longo dos periodos de Alta e Baixa Energia. Tal Fato ESTA Associado à Baixa disponibilidade de material de sedimentar Grosso that FICA retido ao Largo do Litoral. Os galgamentos provocaram Danos na Infraestrutura Costeira e configurou uma FormaÃÃo de Uma planÃcie Lavada, potencializando a vulnerabilidade da Ãrea de inundaÃÃo. O Conhecimento CientÃfico dos Impactos das ressacas do Mar e dos SEUS Processos Associados se mostrou Como Uma Importante Ferramenta Para O Manejo EO gerenciamento de litorais TurÃsticos Urbanos.

Delivery of sediment to beach-dune complexes along the northern California coast, as elsewhere, is controlled by littoral and aeolian processes governed largely by oceanic and meteorological conditions such as wind speed and direction, wave characteristics and water level fluctuations. Furthermore, patterns of sediment deposition on foredunes are controlled by the zonation, density and physical structure of dominant vegetation assemblages. This study explores the link between varying oceanic, meteorological and ecological patterns and coastal foredune morphodynamics at a site within the Humboldt Bay National Wildlife Refuge (HBNWR) near Arcata, CA, to provide coastal managers a local context of foredune erosion and accretion. At a site within the HBNWR a 75-year north to south alongshore gradient in foredune response was observed during the study period. Foredunes in the north experience seaward progradation (up to +0.51 m a-1) and greater sediment volumes then southern foredunes, characterized by foredune retreat (up to -0.49 m a-1) and larger erosive feature areas. Seasonal signatures of a previously observed bi-directional littoral drift partially inform the interpretation of an alongshore gradient in foredune position. In the summer, wind and wave directions were out of the NNW, combined with north to south littoral drift and significant sediment input into the northern beaches. During the winter, the dominant drift direction was from the south to the north, accompanied by large waves, high water levels and beach erosion. Following a comprehensive morpho-ecological model of foredune evolution (Hesp, 1988; 2002), greater foredune volumes, dense vegetation and seaward progradation are indicative of stage 1 foredunes. Transitioning to the south, lower vegetation densities and seaward retreat support a classification of stage 3 developed foredunes, characterized by shorter, more hummocky morphologies. Meteorological patterns and disturbance to vegetation concurrently influence foredune response and recovery to erosive wind, wave and water level events. As such, seasonal to interannual patterns of foredune morphodynamics may be altered following periods of both environmental and human induced vegetation disturbance (i.e., seasonal phenology, dynamic restoration). At a section of foredune in the northern HBNWR, a dynamic restoration project was implemented with the first stages of vegetation removal occurring in August, 2015. In a year following vegetation disturbance through preliminary stages of restoration an annual sediment budget examination indicates net accretion on the foredune (+0.54 m3 m-2) while net erosion occurred on the beach (-0.38 m3 m-2). At smaller seasonal scales site-wide erosion occurred in the winter due to high-water and wave run-up recorded during intense storms. Summer monitoring reveals site-wide accretion due to beach rebuilding, heightened aeolian activity and an increase in vegetation cover. As such, seasonal sediment budgets that influence longer-term patterns of foredune development may be primarily controlled by the amount of sediment available on the beach for aeolian transport and secondarily by localized presence/absence of vegetation. Results of this study provide insight into the impact of continued coastal disturbance on foredune morphodynamics, around which a framework for future vegetation management projects may be implemented. / Graduate

Sandy beaches are vulnerable to extreme erosion during large storms, as well as gradual erosion processes over months and years. Without monitoring and adaptation strategies, erosion can put people, homes, and other infrastructure at risk. To effectively manage beach resources and respond to erosion hazards, coastal managers must have a reliable means of surveying the beach to monitor erosion and accretion. These elevation surveys typically incorporate traditional ground-based surveying methods or lidar surveys flown from large, fixed-wing aircraft. While both strategies are effective, advancements in photogrammetric technology offers a new solution for topographic surveying: Structure from Motion (SfM). Using a set of overlapping aerial photographs, the SfM workflow can generate accurate topographic surveys, and promises to provide a fast, inexpensive, and reliable method for routine beach surveying. Unmanned aerial vehicles (UAVs) are often successfully employed for SfM surveys but can be limited by poor weather ad government regulations, which can make flying difficult or impossible. To circumvent these limitations, a digital camera can be attached to a tall pole on a mobile platform to obtain aerial imagery, avoiding the restrictions of UAV flight. This thesis compares these two techniques of image acquisition for routine beach monitoring. Three surveys were conducted at monthly intervals on a beach on the central South Carolina coast, using both UAV and pole photogrammetry. While both methods use the same software and photogrammetric workflow, the UAV produced better results with far fewer processing artifacts compared to pole photogrammetry. / Master of Science / Beach environments are vulnerable to extreme erosion, especially in the face of sea level rise and large storms like hurricanes. Monitoring erosion is a crucial part of a coastal management strategy, to mitigate risk to coastal hazards like extreme erosion, storm surge, and flooding. Erosion monitoring usually involves repeated elevation surveys to determine how much sand is being lost from the beach, and where that sand is being eroded away. Within the past decade, Structure from Motion (SfM) photogrammetry, the process of deriving ground elevation maps from multiple overlapping aerial photographs, has become a common technique for repeated elevation surveys. Unmanned aerial vehicles (UAVs) are often used to gather aerial imagery for SfM elevation surveys but are limited by poor weather conditions and government flight regulations, both of which can prohibit flight. However, similar aerial photographs can be taken with a camera mounted atop a tall pole, which can be used in wider range of weather conditions and without government regulations, providing an alternative when UAV flight is not an option. This study compares these two platforms for routine beach erosion monitoring surveys, evaluating them based on performance, cost, and feasibility. The UAV system is found to be fast, affordable, and effective, while the pole photogrammetry system is heavily affected by the slow speed of surveying and processing errors that make it unusable without significant improvement.

A technique to extract the shoreline from optical satellite images has been developed, evaluated and applied to the case study site of Progreso, Yucatán, México. This site was chosen as it is frequently subject to hurricanes, shows shoreline erosion and has a paucity of coastal data. The area under investigation is an 8 km length of shoreline that faces north into the Gulf of México. A novel method to extract satellite-derived shorelines (SDS) was developed ensuring the maximum contrast between sea and land. The SDS was validated using quasisimultaneous in situ shoreline measurements from one day in two different years (2008 and 2010). The in situ shoreline measurements recorded the instantaneous shorewards extent of the wave run-up when walking along the beach. The validation of SDS revealed that the SDS locates consistently seawards of the in situ shoreline, explained by: a) the water depth that an optical satellite image requires to identify a pixel either as sea or land, and b) the shorewards extent of the wave run-up. At Progreso, the overall distance between SDS and in situ shoreline is 5.6 m on average and standard deviation of 1.37 m (in the horizontal) over 8 km of shoreline. For an accurate location of the mean SDS, estimation of the shorewards extent of the wave run-up, tidal level and inter-tidal beach slope were required. In situ measurements regarding the beach profile, shoreline location and water levels were taken into consideration to achieve this. The shoreline change observed over a 6.5 year period allowed the estimation of intraannual and inter-annual shoreline changes and progressive changes in the shoreline location. The intra-annual shoreline change revealed seasonality in the shoreline position. The shoreline position from late winter (March 20, 2004) was landwards (approx. 5 to 9 m) in relation to the earlier winter shoreline position (November 11, 2003). The assessed SDSs from the hurricane season (June to November) are at the landwards envelope limit during the year, between -30 to 15 m in relation to the estimated mean SDS. The largest landward movement (100 m) is related to Hurricane Ivan, detected 13 days after the hurricane passed by Yucatán. The inter-annual shoreline change highlighted that an approximate length of 6 km of shoreline is retreating at a rate between -2.4 and -1.2 m per year. Such estimates of shoreline change would not be possible using other available coastal information at this site. The results of this research show that optical satellite images can be used to study shoreline change over large spatial scales (> 5 km), as well as in short (< 1 yr) and long (> 5 yrs) temporal scales.

Submitted by Irene Nascimento (irene.kessia@ufpe.br) on 2016-09-14T19:25:48Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação Athos Farias Menezes 2016.pdf: 6385036 bytes, checksum: a2522df55623cf13d58d7d17b4302fb7 (MD5) / Made available in DSpace on 2016-09-14T19:25:48Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação Athos Farias Menezes 2016.pdf: 6385036 bytes, checksum: a2522df55623cf13d58d7d17b4302fb7 (MD5) Previous issue date: 2016-03-23 / Facepe / A erosão costeira é um fenômeno natural encontrado em diversos ambientes litorâneos em todo o mundo. No entanto a ocupação antrópica desordenada pode potencializar o processo erosivo, como é o caso do litoral do estado de Pernambuco, onde 43,8% da população está localizada no ambiente litorâneo que se estende ao longo de 13 municípios. Observando esta problemática, o presente trabalho foi desenvolvido com o intuito de avaliara vulnerabilidade à erosão costeira através do processamento de imagens de satélite de alta resolução e sistemas de informações geográficas (SIG),a partir de indicadores ambientais e antrópicos. A presente pesquisa foi dividida em três etapas, a primeira visa caracterizar a vulnerabilidade à erosão costeira em escala local nas praias de Piedade (município de Jaboatão dos Guararapes) e Paiva (município do Cabo de Santo Agostinho), ressaltando as diferentes características atribuídas as mesmas. Na primeira praia destacou-se a intensa urbanização, com mais de 60% de interferência antrópica nos setores avaliados, enquanto a segunda se demonstrou conter um bom desenvolvimento de áreas vegetais preservadas mais de 55% do total analisado. Na segunda etapa, foi mostrado o uso dos geoindicadores em escala regional para todo o litoral pernambucano, destacando cenários de intensa vulnerabilidade nas cidades do núcleo metropolitano, enquanto em praias de baixa presença antrópica, como no setor sul, foram destacados baixos índices de vulnerabilidade, enquanto no setor norte foram atribuídos valores moderados. Na terceira etapa deste trabalho trabalho foi apresentado a utilização da interpretação de imagens de alta resolução espacial e métodos automáticos e semiautomáticos na identificação dos geoindicadores na Praia do Forte Orange (município da Ilha de Itamaracá) evidenciando feições sedimentares oriundas do Canal de Santa Cruz, mas com a presença de feições erosivas. De forma geral este trabalho visualiza destacar a importância de métodos alternativos na identificação de áreas com potenciais erosivos, a partir de dados orbitais que acarretarão em uma otimização do tempo para na tomada de decisões públicas acerca dos ambientes litorâneos. / The coastal erosion is a natural phenomenon found in many coastal environments worldwide. One of the causes of unorganized human occupation near coastal areas is erosion. An example of erosion caused by anthropogenic activities is found in the coastal areas of Pernambuco State, Brazil, where 43.8% of the state population live nearthe state’s coastal environments, extending over 13 cities. The current study is divided in three chapters and focuses on the coastal beaches vulnerability evaluation and identification of the vulnerability of coastal erosion caused by anthropogenic and environmental factors, using tools as high resolution satellite images and geographic information systems. First part aims to characterize the vulnerability of beaches to coastal erosion in a local scale.The areas of study are Piedade (city of Jaboatão dos Guararapes) and Paiva beaches (city of Cabo de Santo Agostinho) in Pernambuco State, Brazil, with geomorphological and dynamic characteristics variablity. Piedade beach has intensive urbanization, indicating more than 60% of anthropogenic interference in all evaluated sectors, while Paiya beachis covered by vegetation approximately 55% of total area. In second part, several geoindicators were analyzed in a regional scale along the Pernambuco’s coastline. Different scenarios of high vulnerability were examined in the cities of the metropolitan area, on beaches of low and high anthropogenic activities. The first results, showed low indication of vulnerability at the southen sectorcompared to the northen sector which showed moderate risk of erosion. Finally, in section three,high resolution satellite images were used to identify geoindicators by automaticand semi-automatic approaches in order to identify erosional features. In this chapter the study the Forte Orange beach (city of Ilha de Itamaraca) highlighting sedimentary features of the Canal de Santa Cruz and the presence of erosional features. This research highlights the importance of alternative identification methods for areas under potential erosion risk. The proposed methods in this study are very efficient and can produce accurate and fast results, which can be valuable to the public, environmental agencies, porotection and decision makers of coastal environments.

Storms have been impacting coastal morphodynamics directly due to its intensifying effects over the years. Climate change has caused an exponential impact on storms and therefore morphodynamic changes in the coasts. A specific land that has constantly been threatened is Dauphin Island, a barrier island in Alabama. Over time, it has experienced a total land loss of 100 ft of shoreline over the past of 3 decades and an overall 16% land loss of the island due to the intensifying effects of storms due to a changing climate. In this study, we use Hurricane Ivan as an example. In order to analyze the effects of a future scenario we incorporate the effects of sea level rise. Therefore, we compare three different scenarios of Hurricane Ivan including its current scenario in 2004, current scenario with sea level and future scenario with sea level. Increases in storm surge include wind speed, minimum central pressure and translation speed. These are all factors affecting the breaching in the barrier island. We aim to show how climate change can intensify the effects of hurricanes and impact coastal erosion by comparing a future climate with current climate. We use Hurricane Ivan in Dauphin Island as a case study.

Louisiana’s wetlands are losing land in response to sea level changes, anthropogenic influences and natural marine processes. Historical satellite image analysis reveals that between 2005 and 2015, fifteen tidal creeks in Barataria Bay, Louisiana eroded at the rate of 1.80 m/yr (± 1.98 m), and the open water area behind these creeks enlarged at the rate of 530.00 m2/yr (± 204.80 m2). This research revealed that selected tidal creeks within the estuary have cross-sectional areas larger (2639% larger) than established ocean-inlet equilibrium models would predict. This work suggests that tidal prism to tidal creek cross-sectional area relationships in Barataria Bay are most strongly shaped by creek exposure to waves and secondarily by tide range and currents. A trend of increased inlet erosion rates due to large fetch distances is evident, but impacts from storm driven subtidal variations also play an important role.