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Texas A&M University
1.
Cox, Nicholas Carroll.
The Influence of Nearshore Bars on Infragravity Energy at the Shoreline.
Degree: MS, Civil Engineering, 2012, Texas A&M University
URL: http://hdl.handle.net/1969.1/ETD-TAMU-2011-12-10398
► Bathymetric features such as nearshore sandbars can alter local nearshore hydrodynamic processes such as the production of infragravity energy. These bathymetric features may act to…
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▼ Bathymetric features such as nearshore
sandbars can alter local nearshore hydrodynamic processes such as the production of infragravity energy. These bathymetric features may act to reduce or increase the amount of infragravity energy that reaches the shoreline. To determine the influence of the bathymetric features on infragravity energy, the numerical nearshore processes model XBeach was used to simulate infragravity energy at the shoreline. Numerical simulations were completed for three types of bathymetric scenarios: continuous alongshore bar, bar-rip, and no-bar.
The presence of the bar reduces the amount of infragravity energy at the shoreline when compared with the no-bar scenario. This reduction was characterized by modifying an empirical parameterization for significant infragravity swash developed by Stockdon et al. (2006) for barred beaches. Results show that the amount of infragravity energy in the form of swash is dependent on the bar height and depth, in addition to the offshore wave height and wavelength.
The bar-rip bathymetry produces significant alongshore variation in infragravity energy. The alongshore variations may be due to refracted wave energy or the production of an edge wave by the rip. The magnitude of infragravity energy in the alongshore direction is found to be correlated with the surf zone width. Finally, erosion for the bar-rip scenario is studied qualitatively. The shape of the shoreline is modified during storm events, and is found to take the shape of the alongshore distribution of infragravity energy.
Since infragravity swash influences beach erosion, results of this research may be used as part of an erosion vulnerability scale. Such information on erosion vulnerability is important for the design of coastal protection systems and the protection of coastal communities.
Advisors/Committee Members: Irish, Jennifer (advisor), Kaihatu, James (advisor), Weiss, Robert (committee member).
Subjects/Keywords: Coastal Engineering; Bars; Sandbars; Infragravity; Runup; Swash
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APA (6th Edition):
Cox, N. C. (2012). The Influence of Nearshore Bars on Infragravity Energy at the Shoreline. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2011-12-10398
Chicago Manual of Style (16th Edition):
Cox, Nicholas Carroll. “The Influence of Nearshore Bars on Infragravity Energy at the Shoreline.” 2012. Masters Thesis, Texas A&M University. Accessed January 25, 2021.
http://hdl.handle.net/1969.1/ETD-TAMU-2011-12-10398.
MLA Handbook (7th Edition):
Cox, Nicholas Carroll. “The Influence of Nearshore Bars on Infragravity Energy at the Shoreline.” 2012. Web. 25 Jan 2021.
Vancouver:
Cox NC. The Influence of Nearshore Bars on Infragravity Energy at the Shoreline. [Internet] [Masters thesis]. Texas A&M University; 2012. [cited 2021 Jan 25].
Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2011-12-10398.
Council of Science Editors:
Cox NC. The Influence of Nearshore Bars on Infragravity Energy at the Shoreline. [Masters Thesis]. Texas A&M University; 2012. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2011-12-10398

Delft University of Technology
2.
Kemp, L. (author).
The evolution of sandbars along the Colorado River downstream of the Glen Canyon Dam.
Degree: 2010, Delft University of Technology
URL: http://resolver.tudelft.nl/uuid:0a522b7b-82dc-4aa4-933f-dbe8ec434df9
► The Colorado River in the Grand Canyon area has a lot of sandbars but they are eroding. Since the building of the Glen Canyon Dam…
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▼ The Colorado River in the Grand Canyon area has a lot of sandbars but they are eroding. Since the building of the Glen Canyon Dam and the Hoover Dam in the 1960s, sediment is trapped in the upstream lake. The inflow of water is clear, cold and nearly sediment free. The only noticeable remaining inflow of sediment in the Colorado River is by two tributaries which merge with the Colorado River. This sediment is mostly transported as bed load in downstream direction during normal flow conditions, and does not contribute to sandbar building. The erosion of sandbars has been researched by the United States Geological Survey for decades. Large field experiments are part of this research. The fourth experiment was the high-flow experiment of 2008. During the high-flow experiment of 2008 a dam release of 42000 cfs (1134 m3/s) was bypassed through the dam for 60 hours. The high velocities would bring sediment from the riverbed in suspension. The sediment is then deposited in low-velocity areas. The main question in this research is whether it is possible with a specified dam release, to create sandbars and how they can remain stable on the long term. To answer this question the software program Delft3D is used for the simulation of the sandbar creation. For the long term stability of the bars an image transformation was executed, and for the short term stability the geotechnical program PLAXIS was used. For the situation in the Willie Taylor and Eminence pools a dam release can be determined so sandbars will be created and remain stable for the long term. Sandbars can be created during a high discharge under sediment enriched conditions. The erosion of the sandbars can be set to a minimum when the drawdown of the water level takes 5 days, so the sandbars are almost fully drained. However, implications of erosion at other parts of the sandbar (other than the banks) should be considered using the Delft3D model. The daily fluctuations should be set to a minimum especially in the first period after the flood.
Hydraulic Engineering
Civil Engineering and Geosciences
Advisors/Committee Members: De Vriend, H.J. (mentor), Sloff, C.J. (mentor), Mosselman, E. (mentor), Uijttewaal, W.S.J. (mentor), Van Prooijen, B.C. (mentor).
Subjects/Keywords: Delft3D; PLAXIS; sandbars
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
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APA (6th Edition):
Kemp, L. (. (2010). The evolution of sandbars along the Colorado River downstream of the Glen Canyon Dam. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:0a522b7b-82dc-4aa4-933f-dbe8ec434df9
Chicago Manual of Style (16th Edition):
Kemp, L (author). “The evolution of sandbars along the Colorado River downstream of the Glen Canyon Dam.” 2010. Masters Thesis, Delft University of Technology. Accessed January 25, 2021.
http://resolver.tudelft.nl/uuid:0a522b7b-82dc-4aa4-933f-dbe8ec434df9.
MLA Handbook (7th Edition):
Kemp, L (author). “The evolution of sandbars along the Colorado River downstream of the Glen Canyon Dam.” 2010. Web. 25 Jan 2021.
Vancouver:
Kemp L(. The evolution of sandbars along the Colorado River downstream of the Glen Canyon Dam. [Internet] [Masters thesis]. Delft University of Technology; 2010. [cited 2021 Jan 25].
Available from: http://resolver.tudelft.nl/uuid:0a522b7b-82dc-4aa4-933f-dbe8ec434df9.
Council of Science Editors:
Kemp L(. The evolution of sandbars along the Colorado River downstream of the Glen Canyon Dam. [Masters Thesis]. Delft University of Technology; 2010. Available from: http://resolver.tudelft.nl/uuid:0a522b7b-82dc-4aa4-933f-dbe8ec434df9

Delft University of Technology
3.
Loozen, M.M. (author).
Relation between vegetation and sandbar dynamics in the Colorado River.
Degree: 2017, Delft University of Technology
URL: http://resolver.tudelft.nl/uuid:cefeca02-2518-479a-b047-f3ef1cef8e00
► The Colorado River with a total length of 2330 km is located in the Southwest of North America, originating from the Rocky Mountains and flowing…
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▼ The Colorado River with a total length of 2330 km is located in the Southwest of North America, originating from the Rocky Mountains and flowing into the Gulf of California. In 1963 the Glen Canyon Dam was built to generate hydropower. The construction of the dam caused several significant changes in the river system. One of these changes is the expansion of the riparian vegetation. Because of its magnitude and importance as a natural water carrier, the Colorado River has been studied extensively for decades. One can argue that the
sandbars in the Colorado River are well mapped and its dynamics are well understood. Additionally, the species of riparian vegetation, the location of growth as well as the dimension of vegetation changes are extensively mapped. However, the influence of the aforementioned riparian vegetation expansion on the sandbar dynamics is poorly understood. It is crucial to shed light on this correlation as the dynamics of the system indicate the course of action and determine the possible activities in the area. The main research objective is to gain better understanding on the correlation between vegetation expansion and sandbar dynamics. Two different methods are used to explain the phenomenon; an analysis of data concerning vegetation and geo-morphology is performed and also a detailed hydraulic and geo-morphodynamic model is created. Seven locations in the Colorado River are selected for the data analysis in the period between 2002 and 2013. Of each location different features are visualized and linked including the geo-morphology of the sandbar and the adjacent channel, the geometry and hydraulics of the channel and finally the vegetation coverage on the
sandbars. As a result of this data analysis a clear relation was found between flood cycles and changes in sandbar volume. Moreover, a clear relation between change in sandbar volume and changes in vegetation coverage was observed. Lastly, a clear relation between the location of vegetation and the bed level changes was found. Finally, several methods in order to improve the analytical results are mentioned. The sandbar selected for modelling purposes is a reattachment bar in the Colorado River, overgrown with a significant amount of vegetation which has expanded remarkably over the years. The flow module of the DELFT3D suite is used. The Baptist model assumptions are used for the representation of vegetation. The parameters determined in the Baptist model are derived from field measurements on arrowweed. The flow features that are affected by the expansion of the riparian vegetation are, among others, the characteristic of the primary and secondary eddy, the deflection on the main stream, the location on the reattachment point and the velocity of the flow in the vegetated areas. Inarguably, the above mentioned changes heavily alter the geomorphology of the system. These changes in geomorphology, on its turn, are likely to influence vegetation succession and even the hydraulics. This lastly mentioned feedback, however, has not been thoroughly…
Advisors/Committee Members: Uijttewaal, W.S.J. (mentor), Sloff, C.J. (mentor), Mueller, E. (mentor), Vargas Luna, A. (mentor).
Subjects/Keywords: Sandbars; Colorado River; Riparian vegetation; Eddies; Numerical modelling
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Loozen, M. M. (. (2017). Relation between vegetation and sandbar dynamics in the Colorado River. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:cefeca02-2518-479a-b047-f3ef1cef8e00
Chicago Manual of Style (16th Edition):
Loozen, M M (author). “Relation between vegetation and sandbar dynamics in the Colorado River.” 2017. Masters Thesis, Delft University of Technology. Accessed January 25, 2021.
http://resolver.tudelft.nl/uuid:cefeca02-2518-479a-b047-f3ef1cef8e00.
MLA Handbook (7th Edition):
Loozen, M M (author). “Relation between vegetation and sandbar dynamics in the Colorado River.” 2017. Web. 25 Jan 2021.
Vancouver:
Loozen MM(. Relation between vegetation and sandbar dynamics in the Colorado River. [Internet] [Masters thesis]. Delft University of Technology; 2017. [cited 2021 Jan 25].
Available from: http://resolver.tudelft.nl/uuid:cefeca02-2518-479a-b047-f3ef1cef8e00.
Council of Science Editors:
Loozen MM(. Relation between vegetation and sandbar dynamics in the Colorado River. [Masters Thesis]. Delft University of Technology; 2017. Available from: http://resolver.tudelft.nl/uuid:cefeca02-2518-479a-b047-f3ef1cef8e00
4.
Barroso, Cassia Pianca.
Dinâmica de bancos e pontais arenosos associados à desembocadura do estuário de Caravelas, BA.
Degree: Mestrado, Oceanografia Química e Geológica, 2009, University of São Paulo
URL: http://www.teses.usp.br/teses/disponiveis/21/21133/tde-30042010-103318/
;
► As desembocaduras são ambientes altamente dinâmicos com suas feições sedimentares representando a complexa interação entre as correntes de maré, descarga fluvial, ondas e a batimetria…
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▼ As desembocaduras são ambientes altamente dinâmicos com suas feições sedimentares representando a complexa interação entre as correntes de maré, descarga fluvial, ondas e a batimetria local. Essas feições arenosas possuem uma forte influência na troca sedimentar das regiões costeiras, afetando a estabilidade das regiões adjacentes como as praias e os sistemas estuarinos. O objetivo do presente trabalho é entender a relativa influência dos principais processos que controlam a evolução morfológica dos bancos arenosos e dos pontais arenosos associados a desembocadura do sistema estuarino do rio Caravelas. Este sistema é formado por diversos canais meandrantes conectados com o oceano através de duas desembocaduras, e está localizado em frente ao parcel de Abrolhos no sul da Bahia. Baseado na coleta de dados de duas campanhas de 16 dias no sistema estuarino, o modelo numérico MIKE21-FM (DHI Water \\& Environment) foi aplicado e validado a fim de avaliar quantitativamente os processos que controlam o sistema. Os módulos hidrodinâmico, propagação de ondas e de transporte de sedimentos do modelo numérico foram utilizados neste estudo. O modelo inclui a retroalimentação das mudanças morfológicas nos cálculos da hidrodinâmica, ondas e transporte de sedimentos. Os experimentos numéricos têm como objetivo avaliar a importância relativa das forçantes físicas no ambiente. Foram elaborados dez experimentos numéricos incluindo condições energéticas extremas, alta energia (alta altura de ondas, descargas e maré de sizígia) e baixa energia (pequena altura de ondas, descarga e maré de quadratura) para um intervalo de direções de ondas; e dois períodos adicionais que incluem as condições medidas na coleta de dados (Período 2008 e Período 2007). Imagens de satélites LANDSAT e CBERS também foram utilizadas para observação das mudanças morfológicas do pontal arenoso e da linha de costa adjacente ao longo dos últimos anos. Os resultados para a calibração e validação do modelo numérico aplicado demostraram que na região de interesse e na plataforma interna o modelo consegue reproduzir o padrão da hidrodinâmica de forma adequada. Os resultados mostraram que a morfodinâmica local é controlada pela interação dos principais processos físicos, entretanto a importância relativa de cada um varia ao longo das diferentes regiões do sistema. A morfologia do canal principal e o transporte de sedimentos são controlados pelos fluxos de maré. Os bancos arenosos são também controlados pela maré, porém as correntes geradas por ondas atuando sobre estes bancos, geram um transporte de sedimentos em direção à costa. O pontal arenoso Ilha do Pontal do Sul é influenciado pelas ondas e pela maré. O mecanismo de transporte de sedimentos no pontal deve-se principalmente a corrente de deriva litorânea gerada pelas ondas e a maneira como os sedimentos são depositados e transportados ao longo do pontal deve-se aos fluxos de maré. Pelas imagens de satélites, observou-se que ao longo dos anos, o pontal apresentou uma acresção em seu comprimento, um afinamento da largura…
Advisors/Committee Members: Siegle, Eduardo.
Subjects/Keywords: bancos arenosos; caravelas; caravelas; desembocadura; inlet; MIKE21; MIKE21; Pontais arenosos; sandbars; Sandspits
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Barroso, C. P. (2009). Dinâmica de bancos e pontais arenosos associados à desembocadura do estuário de Caravelas, BA. (Masters Thesis). University of São Paulo. Retrieved from http://www.teses.usp.br/teses/disponiveis/21/21133/tde-30042010-103318/ ;
Chicago Manual of Style (16th Edition):
Barroso, Cassia Pianca. “Dinâmica de bancos e pontais arenosos associados à desembocadura do estuário de Caravelas, BA.” 2009. Masters Thesis, University of São Paulo. Accessed January 25, 2021.
http://www.teses.usp.br/teses/disponiveis/21/21133/tde-30042010-103318/ ;.
MLA Handbook (7th Edition):
Barroso, Cassia Pianca. “Dinâmica de bancos e pontais arenosos associados à desembocadura do estuário de Caravelas, BA.” 2009. Web. 25 Jan 2021.
Vancouver:
Barroso CP. Dinâmica de bancos e pontais arenosos associados à desembocadura do estuário de Caravelas, BA. [Internet] [Masters thesis]. University of São Paulo; 2009. [cited 2021 Jan 25].
Available from: http://www.teses.usp.br/teses/disponiveis/21/21133/tde-30042010-103318/ ;.
Council of Science Editors:
Barroso CP. Dinâmica de bancos e pontais arenosos associados à desembocadura do estuário de Caravelas, BA. [Masters Thesis]. University of São Paulo; 2009. Available from: http://www.teses.usp.br/teses/disponiveis/21/21133/tde-30042010-103318/ ;
5.
Angnuureng, Donatus Bapentire.
Shoreline response to multi-scale oceanic forcing from video imagery : Réponse de shoreline à forçage océanique multi-échelle à partir d’images vidéo.
Degree: Docteur es, Physique de l'environnement, 2016, Bordeaux
URL: http://www.theses.fr/2016BORD0094
► Le but de cette étude était de développer une méthodologie pour évaluer la résilience des littoraux aux évènements de tempêtes, à des échelles de temps…
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▼ Le but de cette étude était de développer une méthodologie pour évaluer la résilience des littoraux aux évènements de tempêtes, à des échelles de temps différentes pour une plage située à une latitude moyenne (Biscarrosse, France). Un site pilote des tropiques, la plage de Jamestown (Ghana), non soumis aux tempêtes, a également été analysé. 6 ans (2007-2012) de données sur la position du trait de côte,obtenues quotidiennement par imagerie vidéo, ainsi que les prévisions hydrodynamiques (ECMWF EraInterim) ont été analysées. Le climat de vagues est dominé par les tempêtes (Hs> 5% de seuil de dépassement) et leurs fluctuations saisonnières; 75% des tempêtes se produisent en hiver, et plus de 60tempêtes ont été identifiées au cours de la période d'étude. Une régression multiple, montre qu’alors que les intensités des tempêtes actuelle et précédente ont un rôle majeur sur l'impact de la tempête, la marée et les barres sableuses jouent un rôle majeur sur la récupération de plage. La position moyenne du trait de côte calculée sur la période de récupération post-tempête montre que la plage de Biscarrosse se reconstruit rapidement (9 jours) après un évènement isolé et que les séries de tempêtes (clusters) ont un effet cumulatif diminué. Les résultats indiquent que le récurrence individuelle des tempêtes est clé. Si l'intervalle entre deux tempêtes est faible par rapport à la période de récupération, la plage devient plus résistante aux tempêtes suivantes; par conséquent, la première tempête d’une série a un impact plus important que les suivantes. Le trait de côte répond, par ordre décroissant, aux évènements saisonniers,à la fréquence des tempête et aux d’échelle annuelle. La méthode EOF montre de bonnes capacité à séparer la dynamique « uniforme » et « non-uniforme » du littoral et décrit différentes variabilités temporelles: les échelles saisonnières et à court terme dominent, respectivement, la première EOF (2D)et le second mode (3D). Le littoral de Jamestown a été étudié comme base d’un projet pilote entre 2013-2014. Les fluctuations du niveau de l'eau jouent un rôle prédominant sur l’évolution de la position du trait de côte. Les vagues et les estimations des marées obtenues par l’exploitation d’images vidéo sont corrélées avec les données de prévisions. Cette étude pionnière montre que cette technique peut être généralisée à toute l’Afrique de l'Ouest en tenant compte des multiples diversités et de la variabilité du climat régional, à travers un réseau d'observations.
The aim of this study was to develop a methodology to statistically assess the shorelineresilience to storms at different time scales for a storm-dominated mid-latitude beach(Biscarrosse, France). On a pilot base, storm-free tropical Jamestown beach (Ghana) was alsoanalysed. 6-years (2007-2012) of continuous video-derived shoreline data and hindcastedhydrodynamics were analysed. Wave climate is dominated by storms (Hs>5% exceedancelimit) and their seasonal fluctuations; 75% of storms occur in winter with more than 60identified storms during the study…
Advisors/Committee Members: Sénéchal, Nadia (thesis director), Almar, Rafael (thesis director), Castelle, Bruno (thesis director), Appeaning-Addo, Kwasi (thesis director).
Subjects/Keywords: Littoral; Tempêtes; Récupération de plage; Marées; Barres sableuses; Shoreline; Storms; Beach recovery; Tides; Sandbars
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Angnuureng, D. B. (2016). Shoreline response to multi-scale oceanic forcing from video imagery : Réponse de shoreline à forçage océanique multi-échelle à partir d’images vidéo. (Doctoral Dissertation). Bordeaux. Retrieved from http://www.theses.fr/2016BORD0094
Chicago Manual of Style (16th Edition):
Angnuureng, Donatus Bapentire. “Shoreline response to multi-scale oceanic forcing from video imagery : Réponse de shoreline à forçage océanique multi-échelle à partir d’images vidéo.” 2016. Doctoral Dissertation, Bordeaux. Accessed January 25, 2021.
http://www.theses.fr/2016BORD0094.
MLA Handbook (7th Edition):
Angnuureng, Donatus Bapentire. “Shoreline response to multi-scale oceanic forcing from video imagery : Réponse de shoreline à forçage océanique multi-échelle à partir d’images vidéo.” 2016. Web. 25 Jan 2021.
Vancouver:
Angnuureng DB. Shoreline response to multi-scale oceanic forcing from video imagery : Réponse de shoreline à forçage océanique multi-échelle à partir d’images vidéo. [Internet] [Doctoral dissertation]. Bordeaux; 2016. [cited 2021 Jan 25].
Available from: http://www.theses.fr/2016BORD0094.
Council of Science Editors:
Angnuureng DB. Shoreline response to multi-scale oceanic forcing from video imagery : Réponse de shoreline à forçage océanique multi-échelle à partir d’images vidéo. [Doctoral Dissertation]. Bordeaux; 2016. Available from: http://www.theses.fr/2016BORD0094

Delft University of Technology
6.
Athanasiou, Panagiotis (author).
Understanding the interactions between crescentic bars, human interventions and coastline dynamics at the East coast of South Korea.
Degree: 2017, Delft University of Technology
URL: http://resolver.tudelft.nl/uuid:e1d7356f-dad6-4839-8279-a818642c4a4a
► Crescentic sandbars are a commonly observed nearshore feature in coastal zones that strongly influence the surfzone circulations and are connected with the occurrence of rip…
(more)
▼ Crescentic
sandbars are a commonly observed nearshore feature in coastal zones that strongly influence the surfzone circulations and are connected with the occurrence of rip currents. Furthermore, their spatial characteristics have been associated with the shoreline position in the form of shoreline perturbations, indicating morphological coupling between them and in turn affecting the beach width. As changes in the beach width affect coastal infrastructure and user functions such as recreation, understanding the bar dynamics is crucial for coastal zone management. The present work intends to improve this understanding by means of a case study at Anmok beach located at the South Korean East coast. Data analysis is used to estimate the long-term changes of the sandbar characteristics in time, under the influence of the ambient environmental conditions and human interventions. Additionally, this study investigates how to account for these features in modelling frameworks. Available in-situ bathymetric surveys and high resolution aerial photographs are complemented with freely available satellite images in order to extract an estimate of the horizontal position of the sandbar crest line at Anmok beach. The introduction of satellite imagery observations dramatically increases both temporal coverage and frequency of the dataset resulting in 27 years of bar observations. The sandbar characteristics are found to change mainly in response to high wave energy events, while the initial sandbar position seems to be an important factor e.g. the closer the sandbar to the shore the more prone to changes it is. Furthermore, the results indicate that the alongshore migration of the sandbar features and the alongshore component of the wave energy flux show an agreement between their long-term (5-10 years) trends. This highlights the potential of the alongshore wave generated current to migrate the sandbar patterns in the alongshore direction. Moreover, the magnitude of the crescentic length and amplitude in an area 600-700m away from the port decreased after its construction. The use of coastline models that assume alongshore uniform bathymetry can be questioned in cases of pronounced alongshore morphological variability. To this end, the impact of the alongshore variability of the sandbar on net annual sediment transports is investigated with the process based morel Delft3D for a selection of schematized bathymetries, created based on the natural variability of the sandbar at Anmok. It appears that for the symmetrical shaped crescentic
sandbars, which are mostly present at Anmok beach, the influence of the alongshore variability on the net sediment transports is not large (~10%). The shoreline response to different sandbar configurations is investigated by computing alongshore incoming and outgoing sand volumes in cells specified close to the shoreline. It is found that the cross-shore distance between the sandbar and the shoreline is critical for the intensity of the erosion and accretion patterns formed at the coastline.…
Advisors/Committee Members: Reniers, Ad (mentor), Ranasinghe, R. (graduation committee), de Schipper, Matthieu (graduation committee), de Vries, Sierd (graduation committee), Tonnon, PK (graduation committee), de Boer, WP (graduation committee), Delft University of Technology (degree granting institution).
Subjects/Keywords: Satellite Imagery; Crescentic Sandbars; Nearshore morphology; Delft3D; Human interventions; Sediment transport; Coastline position; Empirical models
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Athanasiou, P. (. (2017). Understanding the interactions between crescentic bars, human interventions and coastline dynamics at the East coast of South Korea. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:e1d7356f-dad6-4839-8279-a818642c4a4a
Chicago Manual of Style (16th Edition):
Athanasiou, Panagiotis (author). “Understanding the interactions between crescentic bars, human interventions and coastline dynamics at the East coast of South Korea.” 2017. Masters Thesis, Delft University of Technology. Accessed January 25, 2021.
http://resolver.tudelft.nl/uuid:e1d7356f-dad6-4839-8279-a818642c4a4a.
MLA Handbook (7th Edition):
Athanasiou, Panagiotis (author). “Understanding the interactions between crescentic bars, human interventions and coastline dynamics at the East coast of South Korea.” 2017. Web. 25 Jan 2021.
Vancouver:
Athanasiou P(. Understanding the interactions between crescentic bars, human interventions and coastline dynamics at the East coast of South Korea. [Internet] [Masters thesis]. Delft University of Technology; 2017. [cited 2021 Jan 25].
Available from: http://resolver.tudelft.nl/uuid:e1d7356f-dad6-4839-8279-a818642c4a4a.
Council of Science Editors:
Athanasiou P(. Understanding the interactions between crescentic bars, human interventions and coastline dynamics at the East coast of South Korea. [Masters Thesis]. Delft University of Technology; 2017. Available from: http://resolver.tudelft.nl/uuid:e1d7356f-dad6-4839-8279-a818642c4a4a

Delft University of Technology
7.
Spaans, Lennard (author).
Cross-shore morphodynamics of intertidal bars: A conceptual model, empirical evidence and numerical modelling.
Degree: 2019, Delft University of Technology
URL: http://resolver.tudelft.nl/uuid:7f0fe44f-4f8a-44b7-9bbd-23043e1a8e68
► The beach recovery process determines the resilience of a sandy coast and is an important aspect of the coastal safety. Sediment stored underwater due to…
(more)
▼ The beach recovery process determines the resilience of a sandy coast and is an important aspect of the coastal safety. Sediment stored underwater due to storms is transported onshore by the migration of subtidal and intertidal bars under mild wave conditions. The intertidal zone is an im-portant interface, connecting the marine and aeolian zone and facilitating the transition of hydro-dynamic to aeolian sediment transport. The aim of this study is to investigate the cross-shore mor-phodynamics of intertidal sandbars. The dominant cross-shore sediment transport processes can mainly be divided into surf zone and swash zone processes. The surf zone processes are primarily determined by the balance of wave nonlinearities, undertow and infra-gravity waves. In the swash zone, the cross-shore sediment transport is determined by the balance between the turbulent uprush and the gravity induced backwash. A recent terrestrial laser scanning (TLS) measuring campaign conducted at Kijkduin, the Nether-lands, provided new insight in the intertidal bar behavior. The results of one cross section are ana-lyzed. In a period of 6 weeks, two distinctive intertidal bars formed, grew and migrated onshore during mild wave conditions and eventually eroded again during a storm. Within 5 days, the upper intertidal bar migrated onshore over a distance of 25m and grew with a height of 0.3m, attributed to swash zone processes. Onshore sediment transport fluxes reached values of nearly 2 m3 per meter width in one tidal cycle. The findings are compared with two XBeach models (surf beat model and hydrostatic swash model) which are used to reproduce the observed morphological behavior of the upper intertidal bar. Both models partly reproduce the onshore migration but show deviating results regarding the final growth of the intertidal bar. In contrast to the surf beat model, the morphological changes in the hydrostatic swash model are primarily induced by swash zone processes, which is comparable to the processes in the TLS measurements. Finally, a conceptual model is developed in which four intertidal bar regimes are classified based on the tidal water level. The distinction determines the dominant cross-shore processes for the for-mation, migration, growth and destruction of intertidal bars. The model shows that the swash zone processes are dominant for the onshore migration and growth of intertidal bars in the overwash regime, while the surf zone processes are dominant in the submersion regime. The findings presented in this study provide a better understanding of the intertidal bar behavior. Although the XBeach models did not reproduce the observed behavior completely, there are some pronounced similarities. Further research is required to increase the knowledge of intertidal bar behavior at a variety of sandy coasts and to improve the performance of rocesses-based models like XBeach.
Civil Engineering | Hydraulic Engineering
Advisors/Committee Members: Vos, Sander (mentor), Reniers, Ad (graduation committee), de Vries, Sierd (graduation committee), McCall, Robert (graduation committee), Delft University of Technology (degree granting institution).
Subjects/Keywords: intertidal sandbars; cross-shore sediment transport; conceptual model; terrestrial laser scanning; XBeach
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
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APA (6th Edition):
Spaans, L. (. (2019). Cross-shore morphodynamics of intertidal bars: A conceptual model, empirical evidence and numerical modelling. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:7f0fe44f-4f8a-44b7-9bbd-23043e1a8e68
Chicago Manual of Style (16th Edition):
Spaans, Lennard (author). “Cross-shore morphodynamics of intertidal bars: A conceptual model, empirical evidence and numerical modelling.” 2019. Masters Thesis, Delft University of Technology. Accessed January 25, 2021.
http://resolver.tudelft.nl/uuid:7f0fe44f-4f8a-44b7-9bbd-23043e1a8e68.
MLA Handbook (7th Edition):
Spaans, Lennard (author). “Cross-shore morphodynamics of intertidal bars: A conceptual model, empirical evidence and numerical modelling.” 2019. Web. 25 Jan 2021.
Vancouver:
Spaans L(. Cross-shore morphodynamics of intertidal bars: A conceptual model, empirical evidence and numerical modelling. [Internet] [Masters thesis]. Delft University of Technology; 2019. [cited 2021 Jan 25].
Available from: http://resolver.tudelft.nl/uuid:7f0fe44f-4f8a-44b7-9bbd-23043e1a8e68.
Council of Science Editors:
Spaans L(. Cross-shore morphodynamics of intertidal bars: A conceptual model, empirical evidence and numerical modelling. [Masters Thesis]. Delft University of Technology; 2019. Available from: http://resolver.tudelft.nl/uuid:7f0fe44f-4f8a-44b7-9bbd-23043e1a8e68
8.
Di Leonardo, Diana R.
Regional scale sandbar variability : observations from the U.S. Pacific Northwest.
Degree: MS, Geology, 2012, Oregon State University
URL: http://hdl.handle.net/1957/36079
► Understanding sandbar dynamics and variability is integral to developing a predictive capacity for nearshore flows, sediment transport, morphological change, and ultimately for determining coastline exposure…
(more)
▼ Understanding sandbar dynamics and variability is integral to developing a predictive
capacity for nearshore flows, sediment transport, morphological change, and
ultimately for determining coastline exposure to damaging storm waves. Along the
high-energy U.S. Pacific Northwest (PNW) coast,
sandbars typically dominate the
bathymetry of the active zone. Here we report on a nearshore bathymetric data set that
covers an exceptionally long stretch of coast and crosses several littoral cell
boundaries. Our study area stretches from Point Grenville, Washington to Cascade
Head, Oregon, including 8 littoral cells and approximately 250 km in the alongshore.
We describe and quantify the morphological variability of
sandbars in the PNW over
large spatial scales as well as attempt to explain the inter-littoral cell variability via
trends and variability in environmental parameters. From 560 bathymetric profiles
(~1000 km of measurements) we have extracted over 500 distinct subtidal
sandbars.
The bar zone extends to over 1km from the shoreline in the northern part of the study
area, but only to about 600m in the southern part. Maximum bar crest depths are
typically 7m below MLLW. Bar heights range from a step in the cross-shore profile to
over 3m from crest to trough. The northernmost littoral cells typically have two or
more bars per cross-shore profile whereas the littoral cells in the southern part of our
study area have only one bar. The mean depths of the bars, however, are much more
consistent across littoral cells. The mean depths remain consistent even while the
upper shoreface slope significantly increases from north to south, requiring that the
maximum bar distance from the shoreline decreases from north to south. This regional
gradient in upper shoreface slope is likely a response, at least in part, to a general
coarsening trend in the sediment from north to south and hence linked to variations in
regional geology.
Advisors/Committee Members: Ruggiero, Peter (advisor), Holman, Robert (committee member).
Subjects/Keywords: sandbars; Sand bars – Washington (State) – Pacific Coast
…Introduction
Nearshore sandbars are found in the active zone of sandy coastlines
worldwide, often… …classification systems to
characterize the longshore variability of sandbars (Wright and Short… …Northwest (PNW). Sandbars
dominate the nearshore active zone of the PNW coast (… …variability of sandbars at much
larger spatial scales than has been previously attempted. The PNW… …objectives are to (1) quantify
the spatial variation of sandbars over approximately 250km…
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Di Leonardo, D. R. (2012). Regional scale sandbar variability : observations from the U.S. Pacific Northwest. (Masters Thesis). Oregon State University. Retrieved from http://hdl.handle.net/1957/36079
Chicago Manual of Style (16th Edition):
Di Leonardo, Diana R. “Regional scale sandbar variability : observations from the U.S. Pacific Northwest.” 2012. Masters Thesis, Oregon State University. Accessed January 25, 2021.
http://hdl.handle.net/1957/36079.
MLA Handbook (7th Edition):
Di Leonardo, Diana R. “Regional scale sandbar variability : observations from the U.S. Pacific Northwest.” 2012. Web. 25 Jan 2021.
Vancouver:
Di Leonardo DR. Regional scale sandbar variability : observations from the U.S. Pacific Northwest. [Internet] [Masters thesis]. Oregon State University; 2012. [cited 2021 Jan 25].
Available from: http://hdl.handle.net/1957/36079.
Council of Science Editors:
Di Leonardo DR. Regional scale sandbar variability : observations from the U.S. Pacific Northwest. [Masters Thesis]. Oregon State University; 2012. Available from: http://hdl.handle.net/1957/36079

Delft University of Technology
9.
Smit, M.W.J.
Formation and evolution of nearshore sandbars.
Degree: 2010, Delft University of Technology
URL: http://resolver.tudelft.nl/uuid:8dd0f37e-bbcc-472c-8326-b829a1517e13
;
urn:NBN:nl:ui:24-uuid:8dd0f37e-bbcc-472c-8326-b829a1517e13
;
urn:NBN:nl:ui:24-uuid:8dd0f37e-bbcc-472c-8326-b829a1517e13
;
http://resolver.tudelft.nl/uuid:8dd0f37e-bbcc-472c-8326-b829a1517e13
► The aim of this study is to understand whether hydrodynamic processes or geometrical characteristics play a dominant role in the response of the nearshore sandbar…
(more)
▼ The aim of this study is to understand whether hydrodynamic processes or geometrical characteristics play a dominant role in the response of the nearshore sandbar system to hydrodynamic conditions. To that end a depth-averaged (2DH) process-based model has been used to compute the morphological evolution of nearshore
sandbars. The morphological evolution was computed for an initially alongshore uniform beach profile with two bars with an alongshore length of 7 km, forced with constant hydrodynamic conditions over a period of two weeks. The computations aimed to investigate the evolution of the system. It was found that an identical initial cross-shore profile responds distinctly different to different constant hydrodynamic conditions, showing the role of the hydrodynamic conditions. The length scales of the bars (corresponding to rip channel distances) increased with increasing alongshore velocities and increasing depths of the bar crests. The length scales ranged from 300-700 m for the inner and 600-2000 m for the outer bar. The response time of the system was in the order of days and depends linearly on the local wave height, the alongshore current, the steepness of the bar and inversely on the active volume of the bar. Bars with a smaller volume were found to respond quicker. To speed up the morphological computations, the initial alongshore uniform bathymetries were perturbed with a random seed in the order of cm. Different seedings resulted in different locations of the evolving features, while maintaining the length scales corresponding to the forcing condition. The role of the antecedent morphology was further investigated with computations with an increasing level of initial morphological variability. A high level of variability is for example formed by deep rip channels. With deeply imprinted bathymetrical patterns, the resulting hydrodynamical patterns prohibited the evolution of new patterns. This prohibited the adaptation toward length scales that would match the concurrent forcing conditions if the initial bathymetry would have been alongshore uniform. Only if the level of variability is small (smaller than O 0.5 m), the patterns adjusted toward the expected length scales. This was found for both evolutions with increasing as well as decreasing energy levels. This explains why observed nearshore bar patterns rarely match the concurrent conditions. The antecedent level of variability is often high, which inhibits complete adaptation. Further, the forcing conditions rarely persist for periods of time that are long enough for a system to evolve towards the corresponding length scales even if the initial variability would have been minimal. A hindcast was performed of an observed morphological evolution at Palm Beach, New South Wales, Australia, during a ten day period including a storm event. Palm Beach is a pocket beach of about 2 km length. During the event, the wave energy increased from moderate to storm levels, subsequently decreasing again to moderate conditions. The observed morphological variability…
Advisors/Committee Members: Stive, M.J.F., Reniers, A.J.H.M..
Subjects/Keywords: nearshore sandbars; morphological model; rip channel; pattern; morphologial process
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Smit, M. W. J. (2010). Formation and evolution of nearshore sandbars. (Doctoral Dissertation). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:8dd0f37e-bbcc-472c-8326-b829a1517e13 ; urn:NBN:nl:ui:24-uuid:8dd0f37e-bbcc-472c-8326-b829a1517e13 ; urn:NBN:nl:ui:24-uuid:8dd0f37e-bbcc-472c-8326-b829a1517e13 ; http://resolver.tudelft.nl/uuid:8dd0f37e-bbcc-472c-8326-b829a1517e13
Chicago Manual of Style (16th Edition):
Smit, M W J. “Formation and evolution of nearshore sandbars.” 2010. Doctoral Dissertation, Delft University of Technology. Accessed January 25, 2021.
http://resolver.tudelft.nl/uuid:8dd0f37e-bbcc-472c-8326-b829a1517e13 ; urn:NBN:nl:ui:24-uuid:8dd0f37e-bbcc-472c-8326-b829a1517e13 ; urn:NBN:nl:ui:24-uuid:8dd0f37e-bbcc-472c-8326-b829a1517e13 ; http://resolver.tudelft.nl/uuid:8dd0f37e-bbcc-472c-8326-b829a1517e13.
MLA Handbook (7th Edition):
Smit, M W J. “Formation and evolution of nearshore sandbars.” 2010. Web. 25 Jan 2021.
Vancouver:
Smit MWJ. Formation and evolution of nearshore sandbars. [Internet] [Doctoral dissertation]. Delft University of Technology; 2010. [cited 2021 Jan 25].
Available from: http://resolver.tudelft.nl/uuid:8dd0f37e-bbcc-472c-8326-b829a1517e13 ; urn:NBN:nl:ui:24-uuid:8dd0f37e-bbcc-472c-8326-b829a1517e13 ; urn:NBN:nl:ui:24-uuid:8dd0f37e-bbcc-472c-8326-b829a1517e13 ; http://resolver.tudelft.nl/uuid:8dd0f37e-bbcc-472c-8326-b829a1517e13.
Council of Science Editors:
Smit MWJ. Formation and evolution of nearshore sandbars. [Doctoral Dissertation]. Delft University of Technology; 2010. Available from: http://resolver.tudelft.nl/uuid:8dd0f37e-bbcc-472c-8326-b829a1517e13 ; urn:NBN:nl:ui:24-uuid:8dd0f37e-bbcc-472c-8326-b829a1517e13 ; urn:NBN:nl:ui:24-uuid:8dd0f37e-bbcc-472c-8326-b829a1517e13 ; http://resolver.tudelft.nl/uuid:8dd0f37e-bbcc-472c-8326-b829a1517e13

Massey University
10.
Shand, Roger Duncan.
Offshore migration of coastal sand-bars at Wanganui, New Zealand.
Degree: PhD, Geography, 2000, Massey University
URL: http://hdl.handle.net/10179/2163
► Net offshore bar migration (NOM) refers to the systematic seaward migration of coastal sand-bars across the surf zone. These bars form near the shore-line and…
(more)
▼ Net offshore bar migration (NOM) refers to the systematic seaward migration of coastal sand-bars across the surf zone. These bars form near the shore-line and disappear in the outer surf zone. NOM behaviour is repetitive and has been described as cyclic. Over the past decade NOM has been recognised on the North Carolina coast, the Dutch coast and by the author on the west coast of the New Zealand North Island. The aim of this project is to elaborate on the behaviour and causative processes of NOM. The New Zealand data used in this study comprise a 6.3 year bar-crest record from an approximately six kilometre long field site at Wanganui. These data were collected using aerial and terrestrial photography and supplemented with ground surveys. Image processing techniques were developed for photographic data abstraction and analysis. Published data from the other 'global' NOM sites were analysed and compared after data compatibility procedures had been developed and applied. The NOM cycles were quantified using parameters for NOM width (cross-shore migration distance), duration and rate, together with return period. The global NOM sites are characterised by multiple sand-bars, the predominance of sea waves and a narrow band of storm strength wind and wave conditions. The longer-term (average cyclic) parameter values for the global data-set were as follows: NOM width ranged between 195 and 930 m; duration ranged between 1.2 and 13 years; NOM rate ranged between 35 and 196 m/yr, and NOM return period varied between 1.2 and 14.4 years. NOM characteristics for the global sites were found to be correlated with cross-shore slope, coastal orientation and extreme wave height. The Wanganui bar-crest data were also analysed for shorter-term (within-cycle) bar behaviour. Cross-shore bar migrations had a bimodal frequency distribution. The group of larger migrations, termed 'episodic seaward jumps', significantly influenced the characteristics of individual NOM cycles. Episodic seaward jumps appear to be preceded by the degeneration of the adjacent seaward bar. Longshore non-synchronous variation in NOM characteristics were found to be mainly related to 'bar switching' (longshore bar realignment). Based on the above results, a conceptual morphodynamic model for NOM was formulated. The model incorporates three main components: a drive mechanism; a morphodynamic modification mechanism; and a timing mechanism. Net offshore bar migration is a significant mode of morphological behaviour within the surf zone. Its influence upon other aspects of coastal geomorphology such as shoreline change, and its relationship with existing 'beach-state' based models, require further investigation.
Subjects/Keywords: Sandbar migration;
Net offshore bar migration;
New Zealand sandbars
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Shand, R. D. (2000). Offshore migration of coastal sand-bars at Wanganui, New Zealand. (Doctoral Dissertation). Massey University. Retrieved from http://hdl.handle.net/10179/2163
Chicago Manual of Style (16th Edition):
Shand, Roger Duncan. “Offshore migration of coastal sand-bars at Wanganui, New Zealand.” 2000. Doctoral Dissertation, Massey University. Accessed January 25, 2021.
http://hdl.handle.net/10179/2163.
MLA Handbook (7th Edition):
Shand, Roger Duncan. “Offshore migration of coastal sand-bars at Wanganui, New Zealand.” 2000. Web. 25 Jan 2021.
Vancouver:
Shand RD. Offshore migration of coastal sand-bars at Wanganui, New Zealand. [Internet] [Doctoral dissertation]. Massey University; 2000. [cited 2021 Jan 25].
Available from: http://hdl.handle.net/10179/2163.
Council of Science Editors:
Shand RD. Offshore migration of coastal sand-bars at Wanganui, New Zealand. [Doctoral Dissertation]. Massey University; 2000. Available from: http://hdl.handle.net/10179/2163

Delft University of Technology
11.
van Luit, Bas (author).
Understanding the influence of beach morphology on the alongshore variance in wave run-up on an intermediate reflective beach, considering bars and cusps.
Degree: 2017, Delft University of Technology
URL: http://resolver.tudelft.nl/uuid:6fa08b75-71bb-4126-9df4-07a682105596
► The topic which is considered in this thesis is: understanding the influence of beach morphology on the alongshore variance in wave run-up on an intermediate…
(more)
▼ The topic which is considered in this thesis is: understanding the influence of beach morphology on the alongshore variance in wave run-up on an intermediate reflective beach, considering bars and cusps. The focus of this thesis is laid inside the swash zone, in which the water motion is present of waves that run up and run down on a beach. Energy from wave run-up could deliver erosion to the beach. It is relevant to know what the magnitude is of run-up during extreme events, in order to protect the beach. Several studies are done to wave run-up. There are relations which specify run-up, however, the alongshore variability is not studied in detail and less knowledge is available about this topic. At Anmok beach in South-Korea an intermediate reflective beach is present containing beach cusps and crescentic
sandbars. A rhythmic bar and beach state contains the most complex morphology, furthermore the morphology changes a lot within intermediate beaches (Wright and Short [1]). The characteristics of this beach are used to perform an analysis to the influence of cusp and bar morphology on alongshore variation in wave run-up. Run-up is composed of setup and swash. Setup is the super elevation of the mean water level, swash is ‘’a time-varying location of the intersection between the ocean and the beach’’ according to Stockdon, Holman [2]. Swash can be decomposed into two parts, incident band swash and infragravity band swash. Swash and setup depend on beach slope, deep-water wave height and the deep water period[2]. To analyse the alongshore variability multiple bathymetries have been generated on which 500 waves are modelled for 60 different wave condition. First of all a reference case is modelled with a uniform bathymetry. Secondly beach cusps are used as input with different length scales and at last a beach cusp with crescentic sandbar is used. The length scales of the cusps are 452, 300 and 100 metres. The bathymetries are idealized bathymetries with the characteristics of Anmok beach. The run-up and components are calculated and an analysis is done to the magnitude of run-up and the standard deviation along the beach. The magnitude of run-up is lower for a cusp system compared with the reference situation and even lower for the cusp bar system. Furthermore there are no large differences in magnitude of run-up between different cusp lengths. A larger alongshore variance is observed when a cusp (bar) system is present. A cusp system of 452 metres contains larger run-up at the horn compared with the embayment, this holds for large and small wave heights. The difference is 18% and 8.4% respectively. However, when a cusp bar system is present less alongshore variability is visible and an opposite behaviour is visible for small wave heights. In this case the same pattern can be seen for large wave heights. A difference of 3.68% is seen when the horn is compared with the embayment. However, for small wave heights the run-up is 10.5% smaller at a horn compared with an embayment. A…
Advisors/Committee Members: Reniers, Ad (graduation committee), Hofland, Bas (graduation committee), McCall, Robert (mentor), Delft University of Technology (degree granting institution).
Subjects/Keywords: Beach cusps; Crescentic Sandbars; rhytmic bar and beach state; alongshore variance; runup; swash; infragravity band swash; incident band swash; setup; intermediate reflective beach
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
van Luit, B. (. (2017). Understanding the influence of beach morphology on the alongshore variance in wave run-up on an intermediate reflective beach, considering bars and cusps. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:6fa08b75-71bb-4126-9df4-07a682105596
Chicago Manual of Style (16th Edition):
van Luit, Bas (author). “Understanding the influence of beach morphology on the alongshore variance in wave run-up on an intermediate reflective beach, considering bars and cusps.” 2017. Masters Thesis, Delft University of Technology. Accessed January 25, 2021.
http://resolver.tudelft.nl/uuid:6fa08b75-71bb-4126-9df4-07a682105596.
MLA Handbook (7th Edition):
van Luit, Bas (author). “Understanding the influence of beach morphology on the alongshore variance in wave run-up on an intermediate reflective beach, considering bars and cusps.” 2017. Web. 25 Jan 2021.
Vancouver:
van Luit B(. Understanding the influence of beach morphology on the alongshore variance in wave run-up on an intermediate reflective beach, considering bars and cusps. [Internet] [Masters thesis]. Delft University of Technology; 2017. [cited 2021 Jan 25].
Available from: http://resolver.tudelft.nl/uuid:6fa08b75-71bb-4126-9df4-07a682105596.
Council of Science Editors:
van Luit B(. Understanding the influence of beach morphology on the alongshore variance in wave run-up on an intermediate reflective beach, considering bars and cusps. [Masters Thesis]. Delft University of Technology; 2017. Available from: http://resolver.tudelft.nl/uuid:6fa08b75-71bb-4126-9df4-07a682105596

University of Florida
12.
Absalonsen, Luciano.
Sand Bar Behavior Observations and Modeling.
Degree: PhD, Coastal and Oceanographic Engineering - Civil and Coastal Engineering, 2012, University of Florida
URL: https://ufdc.ufl.edu/UFE0044626
► The relation between the number of sand bars in thenearshore zone and the forcing wave conditions was evaluated using observationsand numerical modeling at Walton and…
(more)
▼ The relation between the number of sand bars in thenearshore zone and the forcing wave conditions was evaluated using observationsand numerical modeling at Walton and Volusia Counties, in the State of Florida.The decadal behavior of the number of bars was well represented using a simplequantitative model that correlates the wave forcing and number of bars. The Dean and Profile non-dimensional parameters, used to determine the number of bars inequilibrium with the wave forcing, presented the best correlation between modeland observations, indicating that wave and sediment characteristics areimportant to predict the number of bars in the nearshore zone. The modelsucceeded in representing the rapid increase in the number of bars during majorstorms or hurricanes and the slower decrease in number of bars during calmperiods. The breakpoint theory used in the short term model capturedthe relationship between the inner and outer bars, where the outer bar tends tobe more linear, since only high waves are able to effectively transportsediments into greater depths. The inner bar morphology is more threedimensional where alongshore differences are more evident. The offshoremigration or increase in the outer bar depth was observed to be the trigger forthe inner bar formation. The short term model represented the number of
sandbars when the surveys were conducted close to periods of high energy when thesand bars were formed or migrated to the position and depth according to thewave forcing that generated the system with multiple bars. It was also observedthat the inner and outer bars are interconnected systems with multiple bars andthe study of this system has to be conducted including all bars at the sametime. ( en )
Advisors/Committee Members: Dean, Robert G (committee chair), Thieke, Robert J (committee member), Sheremet, Alexandru (committee member), Adams, Peter Nelson (committee member), Walton, Todd (committee member).
Subjects/Keywords: Beaches; Counties; Hurricanes; Littoral zones; Modeling; Sandbars; Sediment transport; Sediments; Wave energy; Waves; bar – modeling – observation – sand – sediment – transport; Volusia County ( local )
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Absalonsen, L. (2012). Sand Bar Behavior Observations and Modeling. (Doctoral Dissertation). University of Florida. Retrieved from https://ufdc.ufl.edu/UFE0044626
Chicago Manual of Style (16th Edition):
Absalonsen, Luciano. “Sand Bar Behavior Observations and Modeling.” 2012. Doctoral Dissertation, University of Florida. Accessed January 25, 2021.
https://ufdc.ufl.edu/UFE0044626.
MLA Handbook (7th Edition):
Absalonsen, Luciano. “Sand Bar Behavior Observations and Modeling.” 2012. Web. 25 Jan 2021.
Vancouver:
Absalonsen L. Sand Bar Behavior Observations and Modeling. [Internet] [Doctoral dissertation]. University of Florida; 2012. [cited 2021 Jan 25].
Available from: https://ufdc.ufl.edu/UFE0044626.
Council of Science Editors:
Absalonsen L. Sand Bar Behavior Observations and Modeling. [Doctoral Dissertation]. University of Florida; 2012. Available from: https://ufdc.ufl.edu/UFE0044626
13.
Bouvier, Clément.
Barres d’avant-côte et trait de côte : dynamique, couplage et effets induits par la mise en place d’un atténuateur de houle : Sandbars and shoreline dynamics associated with the implementation of a submerged breakwater.
Degree: Docteur es, Physique de l'environnement, 2019, Bordeaux
URL: http://www.theses.fr/2019BORD0088
► Ces dernières années, de nouvelles stratégies ciblant un accompagnement de la mobilité du trait de côte plutôt que sa fixation ont vu le jour. Parmi…
(more)
▼ Ces dernières années, de nouvelles stratégies ciblant un accompagnement de la mobilité du trait de côte plutôt que sa fixation ont vu le jour. Parmi celles-ci, les ouvrages atténuateur de houle visent à protéger la côte en dissipant l’énergie des vagues par déferlement bathymétrique, tout en restant invisibles depuis la plage. Leur utilisation a toutefois eu des effets contrastés et les processus hydro-sédimentaires induits par ces structures restent mal connus. L’objectif général de ce travail est de mieux comprendre les effets de ces atténuateurs de houle sur la morphodynamique littorale, notamment sur des sites où l’évolution de l’avant-côte est complexe et dynamique. L’observation des effets induits par un atténuateur de houle installé au lido de Sète (Golfe du Lion), sur la dynamique littorale est réalisée via un dispositif vidéo qui permet de caractériser l’évolution morphologique du système. En s’appuyant sur une méthode automatique de correction des images développée dans le cadre de cette thèse, l’estimation de la bathymétrie par inversion de la célérité des vagues et ses erreurs associées sont évaluées pour la première fois en Méditerranée. Les observations montrent que l’atténuateur de houle impacte de manière importante la morphologie et la dynamique des barres sableuses pré-littorales et révèlent que l’élargissement de la plage résulte principalement de son couplage avec la nouvelle forme de barre plus linéaire. Le modèle morphodynamique 2DBeach est ensuite implémenté sur Sète et sur un second site atelier en Australie où un récif artificiel de taille et de forme différente a été mis en place. Les simulations réalisées permettent de déterminer les circulations induites par ces ouvrages ainsi que les évolutions sédimentaires associées. Enfin, ce travail met en lumière les différents processus physiques contrôlant l’influence d’un atténuateur de houle sur les évolutions morphologiques des barres sableuses pré-littorales et du trait de côte, et renforce des connaissances essentielles à la gestion durable des plages sableuses.
In recent years, traditional coastal defense strategy has become increasingly unpopular as it is costly and lastingly scars the landscape with sometimes limited effectiveness or even adverse impact. Mimicking natural reefs, submerged breakwaters aims to protect the coast, decreasing wave energy through wave breaking offshore with the advantage of remaining invisible from the beach. The general objective of this work is to better understand the different morphodynamic processes that interact in the presence of these structures, especially for complex beach morphology with highly dynamic sandbars. The observation of the effects induced by a submerged breakwater deployed at the Lido of Sète (Gulf of Lions) on the morphological response is performed using a video monitoring system. Based on an automatic method for image correction developed in this thesis, a video-derived depth inversion algorithm was tested to infer nearshore bathymetry from remotely-sensed wave parameters. Our…
Advisors/Committee Members: Castelle, Bruno (thesis director), Balouin, Yann (thesis director).
Subjects/Keywords: Atténuateur de houle; Barres d’avant côte; Trait de côte; Imagerie vidéo; Inversion bathymétrique; Modèle morphodynamique; Submerged breakwater; Sandbars; Shoreline; Video imagery; Bathymetric inversion; Morphodynamic model
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Bouvier, C. (2019). Barres d’avant-côte et trait de côte : dynamique, couplage et effets induits par la mise en place d’un atténuateur de houle : Sandbars and shoreline dynamics associated with the implementation of a submerged breakwater. (Doctoral Dissertation). Bordeaux. Retrieved from http://www.theses.fr/2019BORD0088
Chicago Manual of Style (16th Edition):
Bouvier, Clément. “Barres d’avant-côte et trait de côte : dynamique, couplage et effets induits par la mise en place d’un atténuateur de houle : Sandbars and shoreline dynamics associated with the implementation of a submerged breakwater.” 2019. Doctoral Dissertation, Bordeaux. Accessed January 25, 2021.
http://www.theses.fr/2019BORD0088.
MLA Handbook (7th Edition):
Bouvier, Clément. “Barres d’avant-côte et trait de côte : dynamique, couplage et effets induits par la mise en place d’un atténuateur de houle : Sandbars and shoreline dynamics associated with the implementation of a submerged breakwater.” 2019. Web. 25 Jan 2021.
Vancouver:
Bouvier C. Barres d’avant-côte et trait de côte : dynamique, couplage et effets induits par la mise en place d’un atténuateur de houle : Sandbars and shoreline dynamics associated with the implementation of a submerged breakwater. [Internet] [Doctoral dissertation]. Bordeaux; 2019. [cited 2021 Jan 25].
Available from: http://www.theses.fr/2019BORD0088.
Council of Science Editors:
Bouvier C. Barres d’avant-côte et trait de côte : dynamique, couplage et effets induits par la mise en place d’un atténuateur de houle : Sandbars and shoreline dynamics associated with the implementation of a submerged breakwater. [Doctoral Dissertation]. Bordeaux; 2019. Available from: http://www.theses.fr/2019BORD0088
14.
Rutten, J.
Sandbar behaviour along a man-made curved coast.
Degree: 2018, University Utrecht
URL: https://dspace.library.uu.nl/handle/1874/364789
;
URN:NBN:NL:UI:10-1874-364789
;
1874/364789
;
urn:isbn:9789062665075
;
URN:NBN:NL:UI:10-1874-364789
;
https://dspace.library.uu.nl/handle/1874/364789
► Sandbars, submerged ridges of sand roughly parallel to the shoreline, change continuously under time-varying wave conditions. Sandbars migrate onshore and offshore, and meanwhile crescentic patterns…
(more)
▼ Sandbars, submerged ridges of sand roughly parallel to the shoreline, change continuously under time-varying wave conditions.
Sandbars migrate onshore and offshore, and meanwhile crescentic patterns may develop or get destructed. So far, most studies have been based on
sandbars at straight coasts. Curved coasts impose an alongshore variability in coastline orientation and consequently in the local wave conditions, which in turn may affect bar behaviour. Further insight in the effects of coastline curvature on bar behaviour is highly relevant with the increasing trend of constructing concentrated, km-scale nourishments that locally alter the orientation of the coastline. The aim of this thesis is to improve the understanding of sandbar behaviour along the curved coast of the dynamic, km-scale Sand Engine nourishment (The Netherlands) at daily to seasonal timescales. Accuracies of morphologic data were assessed first. Hereto, bed elevations zb were inverted from X-band radar and optical video with two algorithms differing in wavenumber-frequency retrieval, i.e. a FFT method and a cross-spectral method, respectively. Validation with in situmeasurements shows a systematic bias in bed elevation, i.e. too deep at small depths and too shallow at larger depths. A 2.3 m bias by the radar-FFT approachfor shallow depths (zb⩾−6 m) may relate to an inhomogeneous wave field in the 960x960 m analysis tiles. Next to bed elevation accuracies, accuracies were determined of breaker lines in time-averaged, low-tide video images that approximate the position of the sandbar. Consistent with earlier studies, an O(10 m) accuracy was found. To quantify sandbar behaviour, breaker lines were extracted from a 2.4-year data set of daily, low-tide video images, and their cross-shore position and rate of patterning were determined for a box north and west of the Sand Engine’s tip. Both the northern and western side show a seasonal signal of onshore and offshore migration. The northern side differs from the western side in the shape of the bar, the depth of the bar crest and the alongshore wavelength of the patterns. Besides, timing differences in the formation and destruction of patterns, as well as coupling to patterns in the shoreline, are found between both sides. Those geometric and timing differences seem to relate to alongshore differences in wave characteristics imposed by the curved coast, i.e. breaker wave height and local wave angle, respectively. How a curved coast, through local differences in the wave angle and the resulting flow field, contributes to alongshore variability in crescentic pattern formation was systematically explored with a non-linear morphodynamic model. The alongshore positioning and growth rate of patterns are shown to vary with the local breaker angle. Increasingly oblique angles lower the growth rates as the alongshore currents intensify and wave heights reduce with refraction. Growth rates are higher at strongly curved coasts where the wave climate is low oblique. This implies that rip currents, associated with…
Advisors/Committee Members: Ruessink, Gerben, Price, Timothy.
Subjects/Keywords: Sandbars; km-scale nourishment; pattern formation; curved coast; rip currents; depth-inversion
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Rutten, J. (2018). Sandbar behaviour along a man-made curved coast. (Doctoral Dissertation). University Utrecht. Retrieved from https://dspace.library.uu.nl/handle/1874/364789 ; URN:NBN:NL:UI:10-1874-364789 ; 1874/364789 ; urn:isbn:9789062665075 ; URN:NBN:NL:UI:10-1874-364789 ; https://dspace.library.uu.nl/handle/1874/364789
Chicago Manual of Style (16th Edition):
Rutten, J. “Sandbar behaviour along a man-made curved coast.” 2018. Doctoral Dissertation, University Utrecht. Accessed January 25, 2021.
https://dspace.library.uu.nl/handle/1874/364789 ; URN:NBN:NL:UI:10-1874-364789 ; 1874/364789 ; urn:isbn:9789062665075 ; URN:NBN:NL:UI:10-1874-364789 ; https://dspace.library.uu.nl/handle/1874/364789.
MLA Handbook (7th Edition):
Rutten, J. “Sandbar behaviour along a man-made curved coast.” 2018. Web. 25 Jan 2021.
Vancouver:
Rutten J. Sandbar behaviour along a man-made curved coast. [Internet] [Doctoral dissertation]. University Utrecht; 2018. [cited 2021 Jan 25].
Available from: https://dspace.library.uu.nl/handle/1874/364789 ; URN:NBN:NL:UI:10-1874-364789 ; 1874/364789 ; urn:isbn:9789062665075 ; URN:NBN:NL:UI:10-1874-364789 ; https://dspace.library.uu.nl/handle/1874/364789.
Council of Science Editors:
Rutten J. Sandbar behaviour along a man-made curved coast. [Doctoral Dissertation]. University Utrecht; 2018. Available from: https://dspace.library.uu.nl/handle/1874/364789 ; URN:NBN:NL:UI:10-1874-364789 ; 1874/364789 ; urn:isbn:9789062665075 ; URN:NBN:NL:UI:10-1874-364789 ; https://dspace.library.uu.nl/handle/1874/364789

University of Florida
15.
Piercy, Andrew.
Reproduction of the Sandbar Shark, carcharhinus Plumbeus, in the Western North Atlantic Ocean and Gulf of Mexico.
Degree: PhD, Fisheries and Aquatic Sciences - Forest Resources and Conservation, 2009, University of Florida
URL: https://ufdc.ufl.edu/UFE0024745
► The reproduction of the sandbar shark, Carcharhinus plumbeus, in the western North Atlantic Ocean and Gulf of Mexico was examined. Specimens were collected through fishery-dependent…
(more)
▼ The reproduction of the sandbar shark, Carcharhinus plumbeus, in the western North Atlantic Ocean and Gulf of Mexico was examined. Specimens were collected through fishery-dependent and ?independent sampling programs. Morphological measurements of the sharks and reproductive organs were taken. Indices of maturity were constructed using measurements of gonads, genital ducts, and claspers. Sharks were shown to mature between 140 and 160 cm fork length. Gonadosomatic indices and variation in genital duct condition were used to determine seasonal trends in reproduction of mature sharks. Sandbar sharks have discrete seasonal reproductive cycles: males produce sperm from January to May with a peak in May and females develop eggs from January to May with ovulation occurring in June. Females were shown to exhibit a greater than two year reproductive cycle. Embryonic development was assessed through measurements of weights and lengths of uterine contents. Gestation was 12 months, from July to the following June, with parturition in late June. Trends in embryonic and maternal relative conditions were noted. Embryos from larger female sharks exhibited less variation in relative condition. Demographic analysis was used to determine the magnitude of effect that variations in reproductive parameters can have on population growth. Variation in age of maturity and seasonality of reproduction were shown to have small effects on intrinsic population growth. Survival of juvenile age classes was shown to have the greatest impact on population growth. ( en )
Advisors/Committee Members: Murie, Debra J. (committee chair), Allen, Micheal S. (committee member), St. Mary, Colette M. (committee member).
Subjects/Keywords: Embryos; Female animals; Fisheries; Gulfs; Mortality; Oceans; Population growth; Sandbars; Sharks; Spermatozoa; demography, elasmobranch, fish, reproduction, sandbar, shark; Atlantic Ocean ( local )
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Piercy, A. (2009). Reproduction of the Sandbar Shark, carcharhinus Plumbeus, in the Western North Atlantic Ocean and Gulf of Mexico. (Doctoral Dissertation). University of Florida. Retrieved from https://ufdc.ufl.edu/UFE0024745
Chicago Manual of Style (16th Edition):
Piercy, Andrew. “Reproduction of the Sandbar Shark, carcharhinus Plumbeus, in the Western North Atlantic Ocean and Gulf of Mexico.” 2009. Doctoral Dissertation, University of Florida. Accessed January 25, 2021.
https://ufdc.ufl.edu/UFE0024745.
MLA Handbook (7th Edition):
Piercy, Andrew. “Reproduction of the Sandbar Shark, carcharhinus Plumbeus, in the Western North Atlantic Ocean and Gulf of Mexico.” 2009. Web. 25 Jan 2021.
Vancouver:
Piercy A. Reproduction of the Sandbar Shark, carcharhinus Plumbeus, in the Western North Atlantic Ocean and Gulf of Mexico. [Internet] [Doctoral dissertation]. University of Florida; 2009. [cited 2021 Jan 25].
Available from: https://ufdc.ufl.edu/UFE0024745.
Council of Science Editors:
Piercy A. Reproduction of the Sandbar Shark, carcharhinus Plumbeus, in the Western North Atlantic Ocean and Gulf of Mexico. [Doctoral Dissertation]. University of Florida; 2009. Available from: https://ufdc.ufl.edu/UFE0024745
16.
Backiel, Bogumila.
Mapping Sandbars in the Connecticut River Watershed through Aerial Images for Floodplain Conservation.
Degree: University of Massachusetts
URL: https://scholarworks.umass.edu/masters_theses_2/597
► Active geomorphic features of rivers like sandbars provide habitat for endangered and threatened riparian plant and animal species. However, human development has altered flow…
(more)
▼ Active geomorphic features of rivers like
sandbars provide habitat for endangered and threatened riparian plant and animal species. However, human development has altered flow and sediment regimes, thus impairing formation of
sandbars and islands. Large scale mapping of the fluvial geomorphology in river ecosystems like the Connecticut River is are necessary to understand the dynamics of these features and preserve habitat. Orthophotographs from 2012 from United States Department of Agriculture's Farm Service Agency (FSA), National Agriculture Imagery Program (NAIP) were used to develop a model in ArcGIS Pro to identify fluvial geomorphic features in the Connecticut River and 12 of its major tributaries. This multi-stage image classification model identifies and ranks pixels of proximity and similar color to identify and map
sandbars and islands. Locations of
sandbars distribution were mapped and analyzed for each river. In the majority of rivers, sandbar area per reach decreases downstream. For the mainstem, sandbar area decreased towards the mouth but with three increases of
sandbars due to meandering and major tributary confluences of the White and Deerfield rivers. Dams tend to decrease
sandbars downstream but the effect of dams is context specific.
Sandbars are stored upstream of the impoundment on the Black River as expected,
sandbars appear downstream of a dam on the mainstem if a tributary confluence is present. Conservation of high sandbar area reaches and naturally eroding stream banks are necessary for preservation of endangered species. This spatial model for sandbar mapping can be applied in other river ecosystems across the region.
Advisors/Committee Members: Keith H Nislow, Christian O Marks.
Subjects/Keywords: Connecticut River; sandbars; GIS; fluvial geomorphology; floodplains; dams; Ecology and Evolutionary Biology; Environmental Sciences
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Backiel, B. (n.d.). Mapping Sandbars in the Connecticut River Watershed through Aerial Images for Floodplain Conservation. (Thesis). University of Massachusetts. Retrieved from https://scholarworks.umass.edu/masters_theses_2/597
Note: this citation may be lacking information needed for this citation format:
No year of publication.
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Backiel, Bogumila. “Mapping Sandbars in the Connecticut River Watershed through Aerial Images for Floodplain Conservation.” Thesis, University of Massachusetts. Accessed January 25, 2021.
https://scholarworks.umass.edu/masters_theses_2/597.
Note: this citation may be lacking information needed for this citation format:
No year of publication.
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Backiel, Bogumila. “Mapping Sandbars in the Connecticut River Watershed through Aerial Images for Floodplain Conservation.” Web. 25 Jan 2021.
Note: this citation may be lacking information needed for this citation format:
No year of publication.
Vancouver:
Backiel B. Mapping Sandbars in the Connecticut River Watershed through Aerial Images for Floodplain Conservation. [Internet] [Thesis]. University of Massachusetts; [cited 2021 Jan 25].
Available from: https://scholarworks.umass.edu/masters_theses_2/597.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
No year of publication.
Council of Science Editors:
Backiel B. Mapping Sandbars in the Connecticut River Watershed through Aerial Images for Floodplain Conservation. [Thesis]. University of Massachusetts; Available from: https://scholarworks.umass.edu/masters_theses_2/597
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
No year of publication.
17.
Blossier, B. (author).
The reset of a subtidal bar during an energetic event: Application to Le Truc Vert beach case (France).
Degree: 2011, Delft University of Technology
URL: http://resolver.tudelft.nl/uuid:5199c56b-b9a1-445b-9f4d-a107aa010ea6
► A large number of beach morphologies across the world exhibits nearshore sandbars with complex 3D patterns. During large storms, these shapes disappear and the bars…
(more)
▼ A large number of beach morphologies across the world exhibits nearshore sandbars with complex 3D patterns. During large storms, these shapes disappear and the bars get to a certain extent alongshore uniform. This phenomenon is called a reset. Numerous studies have been conducted on the development of the bar shapes (3D) or on the cross-shore migration of sandbars (2D). The present work attends to determine the relevant processes involved in the reset of the three dimensional bars and to describe the relative influence of each of these processes. To perform this study, data collected during the ECORS campaign at Le Truc Vert (France) in 2008 are analysed. In addition, a numerical approach is performed using a new research Delft3D model forced by the Xbeach wave generator to investigate the processes involved in a reset-event. The effects of the hydrodynamic external conditions on the currents in the surfzone are investigated. Then the reset is studied in details in order to understand the role of the different processes taken into account by the numerical model. The significant role of the longshore currents induced by oblique wave incidence is clearly assessed. In addition, the long wave orbital velocities as well as the mean flow related to the short wave forcing control the stirring of sediments and influence the time scale of the reset-event.
Coastal Engineering
Hydraulic Engineering
Civil Engineering and Geosciences
Advisors/Committee Members: Brière, C. (mentor), Stive, M.J.F. (mentor), Walstra, D.J. (mentor), Zijlema, M. (mentor), Van Ormondt, M. (mentor), Reniers, A.J.H.M. (mentor), Roelvink, J.A. (mentor).
Subjects/Keywords: nearshore sandbars; reset; Xbeach; Delft3D; infragravity waves; subtidal bar; process-based modelling; nearshore sediment transport; bar migration; storm; Truc Vert
…Importance of nearshore sandbars
Nearshore sandbars are commonly observed in nature and remarkably… …forced behaviour of sandbars enabled first the elaboration of classifications of so-called… …the structure and
the regularity of nearshore sandbars. In 1993, Masselink and Short… …evolution of sandbars. The morphology can either be
forced by the external conditions or forces… …reached. Especially, there has
been little research on the reset of sandbars and the knowledge…
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Blossier, B. (. (2011). The reset of a subtidal bar during an energetic event: Application to Le Truc Vert beach case (France). (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:5199c56b-b9a1-445b-9f4d-a107aa010ea6
Chicago Manual of Style (16th Edition):
Blossier, B (author). “The reset of a subtidal bar during an energetic event: Application to Le Truc Vert beach case (France).” 2011. Masters Thesis, Delft University of Technology. Accessed January 25, 2021.
http://resolver.tudelft.nl/uuid:5199c56b-b9a1-445b-9f4d-a107aa010ea6.
MLA Handbook (7th Edition):
Blossier, B (author). “The reset of a subtidal bar during an energetic event: Application to Le Truc Vert beach case (France).” 2011. Web. 25 Jan 2021.
Vancouver:
Blossier B(. The reset of a subtidal bar during an energetic event: Application to Le Truc Vert beach case (France). [Internet] [Masters thesis]. Delft University of Technology; 2011. [cited 2021 Jan 25].
Available from: http://resolver.tudelft.nl/uuid:5199c56b-b9a1-445b-9f4d-a107aa010ea6.
Council of Science Editors:
Blossier B(. The reset of a subtidal bar during an energetic event: Application to Le Truc Vert beach case (France). [Masters Thesis]. Delft University of Technology; 2011. Available from: http://resolver.tudelft.nl/uuid:5199c56b-b9a1-445b-9f4d-a107aa010ea6

Delft University of Technology
18.
Walstra, D.J.R.
On the anatomy of nearshore sandbars: A systematic exposition of inter-annual sandbar dynamics.
Degree: 2016, Delft University of Technology
URL: http://resolver.tudelft.nl/uuid:3f86bf04-c6af-486f-b972-bd228d84ebed
;
urn:NBN:nl:ui:24-uuid:3f86bf04-c6af-486f-b972-bd228d84ebed
;
3f86bf04-c6af-486f-b972-bd228d84ebed
;
10.4233/uuid:3f86bf04-c6af-486f-b972-bd228d84ebed
;
urn:isbn:978-94-6186-647-9
;
urn:NBN:nl:ui:24-uuid:3f86bf04-c6af-486f-b972-bd228d84ebed
;
http://resolver.tudelft.nl/uuid:3f86bf04-c6af-486f-b972-bd228d84ebed
► Nearshore sandbars have a lifetime of many years, during which they exhibit cyclic, offshore directed behaviour with strong alongshore coherence. A bar is generated near…
(more)
▼ Nearshore
sandbars have a lifetime of many years, during which they exhibit cyclic, offshore directed behaviour with strong alongshore coherence. A bar is generated near the shoreline and grows in height and width while migrating offshore, before finally decaying at the seaward limit of the surf zone. It may take 10 to 15 years for a bar to exhibit this cycle. Four to five bars may occur simultaneously within a cross-shore bed profile. Alongshore variations in cross-shore bar position and bar amplitude are commonly observed. A strong or abrupt alongshore variability is referred to as a bar switch. At large spatial scales, the inter-annual bar dynamics may vary considerably across sites with very similar environmental settings. In particular, the bar cycle return period (T
r, i.e. the duration between two successive bar decay events) may differ by a factor of three to four. This type of change in T
r appears to be always present in time and is characterized as a persistent bar switch. At smaller (kilometer) scales, bar switches typically occur in areas with similar T
r-values on both sides of a bar switch and occasionally disappear when the bars re-attach. These are characterized as non-persistent bar switches. The assimilation of shoreface nourishments into the coastal system involves a strong interaction with the pre-existing sandbar system. Typically the placement of a shoreface nourishment just seaward of an outer bar reverses the bar cycle temporalily, inducing a landward migration of the bar system. The shoreface nourishment becomes absorbed in the coastal system as the new outer bar. At the distal ends of the shoreface nourishment bar switches often manifest, owing to a distinct difference in the bar migration cycle phase that is induced. Given the importance of the bar-nourishment interaction, an improved understanding of the nearshore bar dynamics is expected to improve the efficacy of shoreface nourishments. Furthermore, the long-term evolution of the nearshore barred profiles is generally considered indicative of the quality of the modelling for the response of the entire nearshore coastal system. Therefore, the ability to perform reliable and robust a-priori, long-term predictions has broad societal relevance in view of anticipated adverse impacts of climate change and sea level rise on the stability of coasts worldwide. Until now the anatomy of the nearshore
sandbars has primarily been studied using field data. Although these studies have provided insight into how the geometric bar parameters respond to the external forcings, no comprehensive conceptual framework is available that explains the full life cycle of a sandbar and its associated characteristics. The overarching objective of this study is to elucidate the anatomy of the inter-annual bar morphology using a combined data and model approach. This overarching objective is in turn devolved into three objectives aiming to understand key features of bar morphology and a further objective to enable a comprehensive…
Advisors/Committee Members: Stive, M.J.F., Ruessink, BG, Reniers, A.J.H.M..
Subjects/Keywords: Sandbars; Bar decay; Process based modeling; Unibest-TC; Cyclic bar behavior; Input reduction; Input filtering; Morphodynamic modeling; alongshore variability; bar switching; Noordwijk; Argus; Jarkus; morphodynamic feedback loop; Egmond; inter-annual bar dynamics
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Walstra, D. J. R. (2016). On the anatomy of nearshore sandbars: A systematic exposition of inter-annual sandbar dynamics. (Doctoral Dissertation). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:3f86bf04-c6af-486f-b972-bd228d84ebed ; urn:NBN:nl:ui:24-uuid:3f86bf04-c6af-486f-b972-bd228d84ebed ; 3f86bf04-c6af-486f-b972-bd228d84ebed ; 10.4233/uuid:3f86bf04-c6af-486f-b972-bd228d84ebed ; urn:isbn:978-94-6186-647-9 ; urn:NBN:nl:ui:24-uuid:3f86bf04-c6af-486f-b972-bd228d84ebed ; http://resolver.tudelft.nl/uuid:3f86bf04-c6af-486f-b972-bd228d84ebed
Chicago Manual of Style (16th Edition):
Walstra, D J R. “On the anatomy of nearshore sandbars: A systematic exposition of inter-annual sandbar dynamics.” 2016. Doctoral Dissertation, Delft University of Technology. Accessed January 25, 2021.
http://resolver.tudelft.nl/uuid:3f86bf04-c6af-486f-b972-bd228d84ebed ; urn:NBN:nl:ui:24-uuid:3f86bf04-c6af-486f-b972-bd228d84ebed ; 3f86bf04-c6af-486f-b972-bd228d84ebed ; 10.4233/uuid:3f86bf04-c6af-486f-b972-bd228d84ebed ; urn:isbn:978-94-6186-647-9 ; urn:NBN:nl:ui:24-uuid:3f86bf04-c6af-486f-b972-bd228d84ebed ; http://resolver.tudelft.nl/uuid:3f86bf04-c6af-486f-b972-bd228d84ebed.
MLA Handbook (7th Edition):
Walstra, D J R. “On the anatomy of nearshore sandbars: A systematic exposition of inter-annual sandbar dynamics.” 2016. Web. 25 Jan 2021.
Vancouver:
Walstra DJR. On the anatomy of nearshore sandbars: A systematic exposition of inter-annual sandbar dynamics. [Internet] [Doctoral dissertation]. Delft University of Technology; 2016. [cited 2021 Jan 25].
Available from: http://resolver.tudelft.nl/uuid:3f86bf04-c6af-486f-b972-bd228d84ebed ; urn:NBN:nl:ui:24-uuid:3f86bf04-c6af-486f-b972-bd228d84ebed ; 3f86bf04-c6af-486f-b972-bd228d84ebed ; 10.4233/uuid:3f86bf04-c6af-486f-b972-bd228d84ebed ; urn:isbn:978-94-6186-647-9 ; urn:NBN:nl:ui:24-uuid:3f86bf04-c6af-486f-b972-bd228d84ebed ; http://resolver.tudelft.nl/uuid:3f86bf04-c6af-486f-b972-bd228d84ebed.
Council of Science Editors:
Walstra DJR. On the anatomy of nearshore sandbars: A systematic exposition of inter-annual sandbar dynamics. [Doctoral Dissertation]. Delft University of Technology; 2016. Available from: http://resolver.tudelft.nl/uuid:3f86bf04-c6af-486f-b972-bd228d84ebed ; urn:NBN:nl:ui:24-uuid:3f86bf04-c6af-486f-b972-bd228d84ebed ; 3f86bf04-c6af-486f-b972-bd228d84ebed ; 10.4233/uuid:3f86bf04-c6af-486f-b972-bd228d84ebed ; urn:isbn:978-94-6186-647-9 ; urn:NBN:nl:ui:24-uuid:3f86bf04-c6af-486f-b972-bd228d84ebed ; http://resolver.tudelft.nl/uuid:3f86bf04-c6af-486f-b972-bd228d84ebed
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