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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

<b>L</b><b>I</b><b>DAR-BASED QUANTIFICATION OF INDIANA LAKE MICHIGAN SHORELINE CHANGES</b>

Tasmiah Ahsan (12503458) 18 April 2024 (has links)
<p dir="ltr">Recent high-water levels in Lake Michigan caused extensive shoreline changes along the Indiana coastline. To evaluate recent shoreline changes of the Indiana coastline along Lake Michigan, topographic LiDAR surveys available for the years 2008, 2012, 2013, 2018, 2020, and 2022 were analyzed. This study included LiDAR data of over 400 cross-shore transects, generated at 100 m spacing. Beach profiles were generated to detect the shoreline position and quantify beach width and nearshore volume change. The analysis revealed accretion of both shoreline and beach width from 2008 to 2013 during a low water level period. The beach was rebuilt with a median increased value of 4 m. On the contrary, the shoreline eroded during increasing and high-water periods. Both shoreline and beach width receded with median values of 41 m and 32 m respectively during the period of water level increase from 2013 to 2020. Consequently, the beach profiles lost a median sand volume of 21.6 m<sup>3</sup>/m. Overall, the Indiana shoreline moved with a median of 18 m landward from 2008 to 2022. However, there was a large amount of spatial variability in the shoreline changes. The shoreline movement varied spatially between 63 m recession to 29 m accretion. Similarly, beach profiles showed a loss of median sand volume of 10 m<sup>3</sup>/m. The volume change ranged from 918 m<sup>3</sup>/m loss to 296 m<sup>3</sup>/m accumulation varying spatially along the shoreline. The largest sand loss was experienced at the downdrift of Michigan city harbor near Mt. Baldy. In addition to the spatial variation, the recession also varied slightly with shoreline type. The natural and hardened beaches were mostly recessional. The recession along the hardened shoreline was influenced by the timing of construction and its proximity to inland areas. Buffered beaches, characterized by a swath of vegetation or dunes, experienced the least erosion.</p>
82

Skärvstenshögen i tid och rum : En landskapsanalys av Upplands skärvstenshögars geografiska och kronologiska placeringsmönster. / The Fire-cracked stone heap in time and space : A landscape analysis of the Uppland county’s geographical and chronological placement patterns

Jeppsson, Amanda January 2019 (has links)
Heaps of fire-cracked stone is an archaeological site category frequently found in Sweden. The heaps were constructed by piling a massive amount of deposited fire-cracked stones and occasionally they contain artefacts, for example, grindstones, ceramics or bones from both humans and animals. The heaps are sometimes also constructed with complex inner stone patterns in forms of e.g. circles and spirals. The heaps have been found all over Sweden, but the largest concentration is associated with the county of Uppland, north of Stockholm in eastern Sweden. In general, the structures have been linked chronologically to the Bronze Age (1800 B.C.–500 B.C.), although the heaps might be one of the least understood features of Scandinavian prehistory, as a result of their complex and varying content and spatial location. The remains are thoroughly debated, and the interpretation of them varies, ranging from graves to household indications, from sacral to profane, from piles of waste to markers of claimed land. The interpretations of the fire cracked stone heaps have mainly been made by comparing the contents of the heaps with finds from the surrounding archaeological landscape.                  In this study, the heaps will be analysed by using a landscape perspective by which they will be examined in relation to dynamic high-resolution shoreline reconstructions, vegetation and local topography. By examining the heaps by applying a high-resolution landscape model, suggests that their placement patterns are strongly connected to past shorelines. The analysis has in turn resulted in a non-prejudicial dating method for the heaps. The shoreline model was in the next step tested by a comparison to 118 published 14C-dates associated with fire-cracked stone heaps by using Kernel Density Estimations (KDE). The main result of the study is that the high-resolution shoreline model, in combination with KDE, provides an effective dating method for heaps of fire-cracked stone, which in the extension suggests an alternative motive for the construction of the heaps.
83

AlteraÃÃes no Perfil Natural da Zona Costeira da Cidade de Fortaleza, CearÃ, ao longo do SÃculo XX / AlteraÃÃes no Perfil Natural da Zona Costeira da Cidade de Fortaleza, CearÃ, ao longo do SÃculo XX

Josà Alegnoberto Leite Fechine 26 June 2007 (has links)
FundaÃÃo de Amparo à Pesquisa do Estado do Cearà / O objetivo deste trabalho à analisar as aÃÃes dos processos naturais, relacionados com as mudanÃas sociais impostas à Ãrea costeira de Fortaleza, Nordeste do Brasil, ao longo do sÃculo XX. O estudo està individualizado em duas faixas: Sudeste/ Noroeste (SE/NO) e Leste/Oeste (L/O). A primeira parte da desembocadura do Rio Cocà atà a Ponta do Mucuripe e a segunda da Ponta do Mucuripe atà Foz do Rio CearÃ, perfazendo um total de 23 km. Estas faixas sÃo feiÃÃes dinÃmicas que vÃm sofrendo com o avanÃo e recuo da linha de costa. A sua posiÃÃo no espaÃo geogrÃfico muda constantemente em vÃrias escalas temporais (diÃrias, sazonais, decadais, seculares e milenares). Desta forma, a faixa de praia de Fortaleza à afetada por um nÃmero muito grande de fatores, alguns de origens naturais e intrinsecamente relacionadas à dinÃmica costeira (erosÃo costeira, variaÃÃo relativa do nÃvel do mar, dispersÃo de sedimentos), outros relacionados com as intervenÃÃes humanas na zona costeira (obras de engenharia, drenagens, aterramento de praias, construÃÃo de espigÃes, muros de contenÃÃo). O impacto ambiental e as mudanÃas, naturais e sociais, nestas Ãreas, sÃo bastante considerÃveis. Por essas razÃes, à intenso o avanÃo da linha de costa na faixa SE â NO (Praia do Futuro, CaÃa e Pesca e Serviluz), ocorrendo engorda do perfil praial. Na faixa L/0, um recuo da linha de costa em direÃÃo ao continente (Praia do Meireles, Praia de Iracema, Pirambu, L/O e Barra do CearÃ) vem se intensificando. Estas aÃÃes se deram de forma mais intensa posteriormente à construÃÃo da grande obra o Porto do Mucuripe, na dÃcada de 1940, que veio alterar drasticamente toda a dinÃmica costeira da cidade de Fortaleza, colocando-se como um marco das mudanÃas ambientais da Ãrea ao longo do sÃculo XX / The objective of this dissertation is to present a synthesis of the natural processes related with the social changes of coastal area of Fortaleza city, Northeast of Brazil, along an area of 23 km, during the 20th century. The study area has been individualized in two bands: southeast/northwest and east/west. The first goes from the mouth of Cocà river until the Mucuripe headland and the second, from this point until the estuary of Cearà river. These bands are dynamic features that are suffering with the advance and recession of the shoreline. Its position changes constantly in many scales (daily and seasonal, but associated with centuries and millenniums). In such a way, the beach band of Fortaleza is affected by a very great number of factors, some of natural origins and related to the coastal dynamics (coastal erosion, relative variation of the sea level, dispersion of sediments), others related with human interventions in the coastal zone (workmanships of engineering, drainings, nourishement of beaches, construction of ridges and seawalls). The envirormental impact and the changes, natural and artificial, in these areas, are considerable. For these reasons there is an intense advance of the shoreline in the band southeast/northwest (Futuro beach, CaÃa e Pesca and Serviluz), with progradation of the beach profile. In the band east/west occurs an intense erosion of the shoreline in direction to the continent (Meireles, Iracema, Pirambu, Barra do CearÃ). These processes are more intense after the construction of the Mucuripe harbor, that modified drastically the coastal dynamics of the studied area and its a marker of the environmental chauges in the coast of Fortaleza city during the 20th century
84

Changing Landscapes – A GIS analysis of Neolithic site location and shore displacement in Eastern Central Sweden.

von Hackwitz, Kim, Stenbäck, Niklas January 2013 (has links)
This article is an attempt to put forward the use of new digital techniques and data for understanding prehistoric landscapes. The starting point is that the specific characteristics of the landscape and of the sites included affect the interpretation. One character is the contemporary landscape and its topographies. Ancient landscapes can be successfully recreated digitally using GIS. By applying GIS methodology, a regression equation and new data, we reinvestigated an hypothesis proposed by Welinder in 1978 concerning the acculturation of the Pitted Ware Culture. The results indicate that a reconstruction of the landscape may alter the understanding of the Neolithic land use and the question of the relocation and termination of the Pitted Ware Culture at the end of Middle Neolithic B.
85

A One-line Numerical Model For Shoreline Evolution Under The Interaction Of Wind Waves And Offshore Breakwaters

Artagan, Salih Serkan 01 July 2006 (has links) (PDF)
A numerical model based on one-line theory is developed to evaluate the wind wave driven longshore sediment transport rate and shoreline change. Model performs wave transformation from deep water through the surf zone and computes the breaking parameters. The formula of longshore sediment transport rate used in the numerical model is selected as a result of comparative studies with the similar expressions and the field measurements. Offshore breakwater module of the numerical model is developed to compute the change of shoreline behind single or multiple offshore breakwaters. The validity of the numerical model was confirmed by comparing model results with the shoreline change given within the sheltered zone behind the offshore breakwaters. A series of offshore breakwaters are hypothetically proposed for a case study where a series of groins were constructed whose numerical model results qualitatively matched well with the field measurements. The results of the influences of offshore breakwaters on the shoreline predicted by the model are discussed comparatively with the case study.
86

Shoreline architecture and sequence stratigraphy of Campanian Iles clastic wedge, Piceance Basin, CO : influence of Laramide movements in Western Interior Seaway

Karaman, Ozge 09 November 2012 (has links)
The Campanian Iles Formation of the Mesaverde Group in northwestern Colorado contains a stacked series of some 11 shoreline sequences that form clastic wedges extending east and southeastwards from the Sevier orogenic belt to the Western Interior Seaway. Iles Formation shorelines and their alluvial and coastal plain equivalents (Neslen Formation, Trail and Rusty members of the Ericson Formation) are well exposed from Utah and from southern Wyoming into northwestern Colorado. The Iles Clastic Wedge was examined in the subsurface Piceance Basin and at outcrops in Meeker and south of Rangely, NW Colorado. The clastic wedge contains low-accommodation regressive-transgressive sequences (8-39 m thick) of Loyd Sandstones, Sego Sandstone, Corcoran Member, and Cozzette Member and their updip-equivalent Neslen Formation strata. Facies associations of the sandstone succession indicate storm-wave dominated coasts that transition seaward into offshore/prodelta mudstones with thin-bedded sandstones and extend landward into tidal/fluvial channels and coal-bearing strata; facies associations also indicate interdeltaic coastal embayments with moderate tidal influence. 14, 75-km-long Piceance Basin transects (dip and strike oriented) makes it possible to evaluate coastline variability, and the progressive southeasterly pinchout of the 11 coastline tongues within the larger Iles Clastic Wedge. The thickness and great updip-downdip extent of the Iles stratigraphic sequences (compared to the underlying Blackhawk or overlying Rollins sequences) support previous observations of a low accommodation setting during this time. It has been suggested that this low accommodation was caused by combined effects of embryonic Laramide uplifts and Sevier subsidence across the region. Uplift or greatly reduced subsidence across the Western Interior Seaway would have caused an increase in coastal embayments as well as generally accelerated coastal regressions and transgressions in this 3.3 My interval. / text
87

Numerical Modeling Of Wind Wave Induced Longshore Sediment Transport

Safak, Ilgar 01 July 2006 (has links) (PDF)
In this study, a numerical model is developed to determine shoreline changes due to wind wave induced longshore sediment transport, by solving sediment continuity equation and taking one line theory as a base, in existence of seawalls, groins, T-groins, offshore breakwaters and beach nourishment projects, whose dimensions and locations may be given arbitrarily. The model computes the transformation of deep water wave characteristics up to the surf zone and eventually gives the result of shoreline changes with user-friendly visual outputs. A method of representative wave input as annual average wave characteristics is presented. Compatibility of the currently developed tool is tested by a case study and it is shown that the results, obtained from the model, are in good agreement qualitatively with field measurements. In the scope of this study, input manner of long term annual wave data into model in miscellaneous ways is also discussed.
88

Monitoramento por dgps e an?lise dos processos erosivos da linha de costa na praia de Pirangi do Norte - Parnamirim / RN

Nascimento, Kleiton Cassemiro do 22 December 2009 (has links)
Made available in DSpace on 2014-12-17T15:03:23Z (GMT). No. of bitstreams: 1 KleitonCN_DISSERT.pdf: 3918645 bytes, checksum: fd0ad2d9340e0d6860f2ffe24703f4ce (MD5) Previous issue date: 2009-12-22 / Through out the course of a steady increase in search and recovery of space in the coastal zone, there is also an expanding concern about the erosion processes of this area. The main problem in coastal areas is that urbanization occurs in a disorderly fashion and unsustainable, further aggravating the problems of coastal dynamics. The study area of this work is located on the southern coast of Pirangi do Norte beach to about 20km south of Natal, capital of Rio Grande do Norte in the Parnamirim City. This area has the length of approximately 1km, divided into three sections (Western, Central and Eastern) with a morphology consisting of a tableland at the top, sea cliffs in the West and Central parts and sand dunes in the Eastern section, both vegetated, and a coastal plain on the inferior part associated with the presence of beach rocks. This study aimed to analyze the erosion processes operating in the excerpt of Pirangi do Norte beach and assess the feasibility of their monitoring making use of DGPS (Global Positioning System Differential mode). During the work it was carried out a physical description of the area through photo-interpretation and site survey after measurement of the shoreline in the period between November 2004 and November 2009 and beach profiles between August 2005 and July 2006. The analysis of the results of the annual surveys showed the occurrence of variations of the shoreline along the stretch traveled. Sites are identified in advancement coast from the sea and it was verified in loco the presence of erosion with deposition of materials on the lower part of the coastal bluff, the former position of the shoreline, showing a false notion of advancing it. This leads to the conclusion that the data collected in a survey of the shoreline should always be accompanied by photographic records of the local area and with the highest rate of erosion, thus avoiding the mistake of treating the deposit materials as evidence of progress coast. At the end of the study, after a review of various works to mitigate the erosion in the coastal zone, it is recommended to the area of study the adoption of an artificial feeding of the beach, aiming the minimization of the erosive effects of the tides. Moreover, it is suggested that even the continuity of monitoring, maintenance of existing vegetation and control of the occupation on the edge of sea cliffs / Em meio a um cont?nuo aumento da busca e valoriza??o do espa?o na zona costeira, cresce tamb?m a preocupa??o sobre os processos erosivos caracter?sticos desta ?rea. O maior problema nas zonas litor?neas ? que a urbaniza??o ocorre de forma desordenada e insustent?vel, agravando ainda mais os problemas decorrentes da din?mica costeira. A ?rea de estudo deste trabalho est? localizada no litoral Sul do Estado na praia de Pirangi do Norte, ? aproximadamente 20km ao Sul de Natal, capital do Rio Grande do Norte, no munic?pio de Parnamirim. Essa ?rea possui uma extens?o aproximada de 1km dividida em tr?s trechos (Oeste, Central e Leste) com morfologia formada por tabuleiro costeiro na parte superior, fal?sias nos trechos Oeste e Central e dunas no trecho Leste, ambas vegetadas, e uma plan?cie costeira na parte inferior associada ? presen?a de recifes de arenito. Este trabalho teve o objetivo de analisar os processos erosivos atuantes no trecho da praia de Pirangi do Norte e avaliar a viabilidade do seu monitoramento fazendo uso do DGPS (Sistema de Posicionamento Global em modo Diferencial). Foi realizada durante o trabalho uma caracteriza??o f?sica da ?rea por meio de fotointerpreta??o e vistoria local seguida de levantamentos da linha de costa no per?odo entre novembro de 2004 e novembro de 2009 e perfis de praia entre agosto de 2005 e julho de 2006. A an?lise sobre os resultados dos levantamentos anuais mostrou a ocorr?ncia de varia??es da linha de costa ao longo do trecho percorrido. Em locais identificados em planta como avan?o da costa em rela??o ao mar foi verificado in loco a presen?a de eros?o com dep?sito de materiais sobre o p? da fal?sia, antiga posi??o da linha de costa, dando a no??o de falso avan?o da mesma. Esse fato leva a conclus?o de que os dados coletados em um levantamento da linha de costa devem ser sempre acompanhados por registros fotogr?ficos da ?rea e locais com maior ?ndice de eros?o, evitando, assim, o equ?voco de tratar materiais de dep?sito como indicio de avan?o de costa. Ao final do trabalho, ap?s uma an?lise das diversas obras de mitiga??o dos processos erosivos na zona costeira, recomenda-se para o local de estudo a ado??o da alimenta??o artificial da praia, visando minimizar os efeitos erosivos das mar?s. Al?m disso, sugere-se ainda a continuidade do monitoramento, manuten??o da vegeta??o existente e controle da ocupa??o na borda dos trechos com fal?sias
89

Coastal dynamics and vulnerability to the coastal erosion of the cities Caucaia and Aquiraz, CearÃ. / DinÃmica costeira e vulnerabilidade à erosÃo do litoral dos municÃpios de Caucaia e Aquiraz, CearÃ.

Marisa Ribeiro Moura 15 May 2012 (has links)
FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / The coastal plains are one of the most fragile ecosystems known, however, have the highest rate of use, occupation, urbanization and population density in the world. This fact demonstrates the need to require specific studies in this area so that your planning is done sustainably. Thus, the present thesis held in the coastal municipalities of Caucaia and Aquiraz, CearÃ, located in the metropolitan region of Fortaleza, aimed to analyze the socio-environmental dynamics of the coastal zone, assessing the levels of vulnerability to erosion of the site. The methodology was performed by monitoring the 12 points marked, in which they were made, field work with the realization of profiles transverse, measurements of height, period and direction of waves and sediment samples collected in the beach zone, dunes and frontal dunes to back morphoscopy and analysis granulometric, and survey data such as winds, rainfall, currents, temperature and tidal fluctuations. According to the results given that the coastal area studied had almost entirely, urbanization and occupation by tourist activities, and this in some specific environments have lower intensity due to unattractive and/or speculation has yet to be inserted so active on the beach. The evolution of the urban city of Caucaia occurred more intensely compared to the occupation of Aquiraz, even the latter has a history older than the first city, a fact proven by the characteristics social and economic. In the oceanographic aspects there was tidal amplitudes monthly maximum 3.1 minimum 2,3 m. In Caucaia the wave height ranged from 0,60 m to 2,10 m Aquiraz a variation of 1,5 m and 0,50 m wave predominance of type sea. The morphoscopy identified in dune environments and beach sediments matte and shiny, which demonstrate the existence of interaction between environments underwater and wind transport. As the modal states, the coast of Caucaia characterized by beaches with a tendency to intermediate stages, resulting in certain periods of the year in the reflective beach stages in Iparana and dissipative stages in Pacheco and IcaraÃ. Already in Aquiraz modal stages were also characterized by beaches tend to intermediate stages, only in getting internships reflective stages in Iguape. It was confirmed the retreat of the shoreline around the coastline studied based on the program DSAS 4.2, with rates ranging from -4,10 m/year to 0,35 m/year in Caucaia and -1,4 m/year to -0,25 m/year in Aquiraz. In view of the foregoing it was found that the coast of Caucaia showed average to high vulnerability to erosion taking place as a major problem in the forms of use and occupancy of interaction between environments of the coastal zone, while in Aquiraz was low to high along its entire length, with the most problematic areas of real estate speculation should be preserved. These implications may clarify why the erosion processes are more intense in coastal Caucaia in relation to coastal Aquiraz, mainly because of the position of the coastline, that is, how the elements studied oceanographic reached the coast, in the case, in coastal Caucaia these are much more intenseIt is concluded that, in comparative diagnosis of the two cities through the methodologies, the erosion indicators, the categories and morphodynamics that, the vulnerability to coastal together with conditions receding coast line and reduced sediment supply, is related mainly with the evolution of the occupation, the use and the forms of dynamic coastal area. / As planÃcies litorÃneas sÃo um dos ecossistemas mais frÃgeis conhecidos, que, no entanto, apresentam o maior Ãndice de uso, ocupaÃÃo, urbanizaÃÃo e densidade demogrÃfica em todo o mundo. Tal fato demonstra a necessidade dessa Ãrea requerer estudos especÃficos para que seu ordenamento seja feito de forma sustentÃvel. Dessa forma, a presente tese, realizada no litoral dos municÃpios de Caucaia e Aquiraz, CearÃ, localizados na regiÃo metropolitana de Fortaleza, teve como objetivo analisar a dinÃmica socioambiental da zona costeira, avaliando os Ãndices de vulnerabilidade à erosÃo do local. A metodologia foi realizada por meio do monitoramento de 12 pontos demarcados, nos quais foram feitos, trabalhos de campo com a realizaÃÃo de perfis transversais, mediÃÃes da altura, perÃodo e direÃÃo das ondas e coletas de amostras de sedimentos na faixa praial e campos de dunas mÃveis e frontais para posterior anÃlise granulomÃtrica e morfoscopia e levantamentos de dados como ventos, pluviometria, correntes, temperatura e oscilaÃÃes das marÃs. Nos resultados obtidos conferiu-se que, a zona costeira estudada apresentou em quase sua totalidade, ocupaÃÃo por urbanizaÃÃo e atividades turÃsticas, tendo esta em alguns pontos especÃficos menor intensidade devido possuir ambientes sem atrativos e/ou a especulaÃÃo imobiliÃria ainda nÃo ter se inserido de forma na praia. A evoluÃÃo urbana do municÃpio de Caucaia se deu de forma mais intensa se comparada à ocupaÃÃo de Aquiraz, mesmo esta Ãltima tendo um histÃrico mais antigo que a do primeiro municÃpio, fato comprovado pelas caracterÃsticas sociais e econÃmicas locais. Nos aspectos oceanogrÃficos verificou-se amplitudes de marÃs mensais com mÃximas de 3,1 m e mÃnimas de 2,3 m. Em Caucaia a altura da onda variou de 0,60 m a 2,10 m e em Aquiraz apresentou variaÃÃo de 1,5 m e 0,50 m e predominÃncia de ondas do tipo sea. A morfoscopia identificou nos ambientes dunares e praiais sedimentos foscos e brilhosos, o que constata a existÃncia da interaÃÃo entre ambientes de transportes eÃlicos e subaquÃticos. Conforme os estados modais, o litoral de Caucaia caracterizou-se com praias de tendÃncia a estÃgios intermediÃrios, obtendo em certos perÃodos do ano estÃgios reflexivos na praia de Iparana e estÃgios dissipativos nas praias de Pacheco e IcaraÃ. Jà em Aquiraz os estÃgios modais tambÃm caracterizaram-se por praias de tendÃncia a estÃgios intermediÃrios, obtendo estÃgios reflexivos apenas na praia do Iguape. Confirmou-se o recuo da linha de costa em todo o litoral analisado, com base no programa DSAS 4.2, com taxas entre -4,10 m/ano a 0,35 m/ano em Caucaia e de -1,4 a -0,25 em Aquiraz. Diante do que foi exposto constatou-se que o litoral de Caucaia apresentou vulnerabilidade mÃdia à alta à erosÃo tendo como problema maior no local as formas de uso e ocupaÃÃo dos ambientes de interaÃÃo entre a zona costeira, enquanto que em Aquiraz foi de baixa à alta em toda sua extensÃo, tendo como problemÃtica maior a especulaÃÃo imobiliÃria de Ãreas que deveriam ser preservadas. Tais implicaÃÃes podem esclarecer o porquà dos processos erosivos serem mais intensos no litoral de Caucaia em relaÃÃo ao litoral de Aquiraz, principalmente por causa da posiÃÃo da linha de costa, isto Ã, da forma como os elementos oceanogrÃficos chegam à costa estudada, no caso, no litoral de Caucaia estes sÃo bem mais intensos. Conclui-se que, no diagnÃstico comparativo dos dois municÃpios por meio das metodologias, dos indicadores erosivos e das categorizaÃÃes morfodinÃmicas que a vulnerabilidade costeira, em conjunto com as condiÃÃes de recuo da linha costa e a diminuiÃÃo do suprimento sedimentar, està relacionada, sobretudo, com a evoluÃÃo da ocupaÃÃo, das formas de uso e da dinÃmica costeira da Ãrea.
90

Les conséquences de l'élévation du niveau marin pour le recul du trait de côte / Impacts of sea-level rise for shoreline changes

Le Cozannet, Gonéri 02 December 2016 (has links)
Dans quelle mesure les variations du niveau marin actuelles agissent-elles sur la mobilité du trait de côte? Cette question est difficile en raison du caractère lacunaire des jeux de données côtières disponibles. Cette thèse montre tout d'abord qu'il est possible d'évaluer l'élévation relative du niveau de la mer en combinant l'interférométrie radar satellitaire l'analyse de données géodésiques ponctuelles telles que le GPS. Elle examine ensuite le cas de littoraux ayant fait l'expérience d'une élévation du niveau de la mer sensiblement différente de la moyenne globale lors des 50 dernières années. Dans le cas d'atolls de Polynésie Française, les données disponibles montrent le rôle majeur des vagues saisonnières et cycloniques pour contrôler l'évolution du trait de côte. Dans certains secteurs, les effets des vagues sont suspectés se combiner avec l'élévation du niveau de la mer pour favoriser l'érosion de secteurs abrités. Dans le cas de la base de données côtière européenne Eurosion, environ 17 000 observations côtières sont disponibles et peuvent être analysées par une méthode d'exploration de données basée sur les réseaux Bayésiens. Une partie de la variabilité spatiale de l'évolution du trait de côte s'explique par le fait que les littoraux de Fennoscandie sont majoritairement en accrétion, alors qu'ils sont affectés par une baisse du niveau de la mer liée au rebond post-glaciaire. D'une manière générale, ces résultats suggèrent qu'il est encore trop tôt pour observer des effets érosifs évidents de l'élévation du niveau de la mer d'origine climatique. Une analyse probabiliste de l'équation du bilan sédimentaire côtier montre que si cette équation est vérifiée, les effets de l'élévation du niveau de la mer deviendront perceptibles à partir de la seconde moitié du XXIe siècle si les objectifs de réduction des gaz à effet de serre ne sont pas atteints. Finalement, cette thèse ouvre un champ de recherches dans le domaine des mathématiques appliquées pour l'étude des conséquences du changement climatique et de l'élévation du niveau de la mer dans les zones côtières. / To which extent does present day sea-level rise affect shoreline changes? This question remains largely open due to the lack of knowledge and data regarding coastal hydrosedimentary processes and relative sea-level changes (i.e., including vertical ground motions). This PhD Thesis first addresses the question of measuring relative sea-level changes using a combination of geodetic data, including satellite-radar interferometry and permanent GPS stations. Then, it examines the case of coasts that experienced sea-level changes significantly different from the global average over the last 50 years. In the case of atoll islands of French Polynesia, the available data illustrate the major role of southern, trade and cyclonic waves in controlling shoreline changes. For some sheltered coasts, waves are suspected to combine with sea-level rise to favour shoreline retreat. In the case of the European coastal database Eurosion, about 17 000 coastal observations are available and have been analysed using a Bayesian network. Here, part of the spatial variability of shoreline changes can be explained by the fact that Fennoscandian coasts are not only accreting, but also uplifting due to the post-glacial rebound. Overall, these results suggest that it is still too early to observe obvious effects of climate-induced sea-level rise. A probabilistic analysis of the coastal sedimentary equation shows that under common assumptions on hydrosedimentary processes, sea-level rise impacts for beaches should become observable during the second half of the 21st century, if the efforts to maintain climate warming below the 2 C threshold fail. Finally, this PhD thesis offers opportunities for stimulating future research in the field of mathematics applied to the question of climate change and sea-level rise impacts to coastal zones.

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