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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.
121

Avaliação e impactos da elevação do nível do mar no Porto de Santos (São Paulo, Brasil). / Evaluation and impacts of sea level rising in Santos Harbor (São Paulo, Brazil).

Raphael de Campos Prats 20 September 2017 (has links)
O Porto de Santos está localizado no litoral Paulista, na costa Sudeste do Brasil e é o maior e mais importante porto do país. Desde 1859 vem sofrendo adaptações e modernizações tanto em suas instalações físicas quanto em sua estrutura administrativa. As variáveis com as quais a Engenharia Civil deve lidar podem ser resumidas basicamente aos fenômenos naturais, pois estes determinam como serão projetadas e construídas as estruturas e instalações. Em projetos portuários, diversas características naturais devem ser mensuradas como, por exemplo, ventos, correntes marítimas, incidência de ondas, tipo de solo em que se encontra o porto, as temperaturas médias do local e, sobretudo, o nível do mar. Os mares e oceanos não possuem superfícies estáveis e apresentam cotas que estão em movimentos constantes. Estas variações se dão basicamente por ondas de curto ou longo período. A maré é uma onda de longo período que causa a variação diária do nível do mar. Atualmente é cada vez maior o interesse da comunidade científica pela temática relacionada às variações do nível do mar. Buscando contribuir com o tema, o presente estudo tem como objetivo principal a análise das variações do nível do mar no Porto de Santos ao longo dos últimos 60 anos, utilizando-se de dados coletados nos três marégrafos da região. Foi elaborada a média móvel desta série com a finalidade de detectar alguma variação significativa. A análise dos dados implicou que fossem considerados períodos de 18,61 anos, correspondentes ao intervalo do ciclo de precessão lunar, de modo a eliminar o efeito da variação astronômica no nível do mar. A elevação do nível máximo, médio e mínimo do mar no período de 1953 a 2008, apresentou uma elevação média de 2,5 mm/ano, resultado semelhante a outros estudos. Foram avaliados também o impacto da variação do nível do mar sobre as estruturas portuárias, indicando os efeitos da elevação nas estruturas, nos cais, nos aparelhos de defensa e ancoragem, nos equipamentos de descarga e outros. / Santos Harbor is at São Paulo\'s coast, in Brazil\'s southeast coast and it is the biggest and the most important port of the country. Since 1859 had been suffering adaptations and modernizations in its installations such as in its administrative structure. The variables that Civil Engineering has to deal with can be resumed basically to the natural phenomena because its determines how projected and built the structures will be. In docks projects, several natural characteristics must be measured, as example, winds, ocean currents, waves incidence, kind of soil that supports the harbor\'s structures, the local medium temperatures and, mainly the sea level. The seas and oceans doesn\'t have stables surfaces and shows levels that are in constant movements. These variations are products of short and long period waves. The tide is a long period wave that causes the daily sea level variation. Actually, the interest of the scientific community in sea level variation is increasing. Aiming to contribute with this theme, the present study has as main objective analyzing the sea level variations at Santos Harbor above the last 60 years, using data collected from three tidal gauges in the region. It was applied the moving average of the series to detect some significant variation. The data analysis demanded that the periods of 18,61 years, which corresponds to the interval of the moon precession cycles, was considered to purge the astronomic variation over the sea level. The maximum sea level, average and minimum sea level, in the period of 1953 and 2008 showed an average increase of 2.5 mm/year, which is similar to other studies. It was evaluated the impact of this sea level rise over the port\'s structures, showing the structural effects, over the docks; in the defense and anchorage equipment, unload equipment and others.
122

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.
123

Biodiversity and ecosystem processes in an experimental island system

Andert, Hagen 15 November 2017 (has links)
No description available.
124

A Risk Assessment Analysis : The risk of saltwater intrusion into freshwater wells and the effects of a futuresea level rise on the Baltic Sea island of Öland

Eriksson, Marcus January 2017 (has links)
Freshwater is essential for a functional society and the human well-being. However, it should not be taken for granted. Freshwater aquifers in coastal are subject to current and future risk of becoming saltwater contaminated – reaching a tipping point. Freshwater security on islands is vulnerable. The aim of this empirical study is to identify the effects of a 2-meter sea level rise and the current risk of well salinization at the Baltic Sea island of Öland, Sweden. A Geographical Information System (GIS) was used to conduct a quantitative risk assessment analysis. Natural and physical parameters affect the risk of intrusion into wells including hydrology, geomorphology, and climatology. Anthropogenic causes and climate change also add to the risk of salinization. However, they are not included in the quantitative study. The spatial distribution of the current risk is mapped in this study and can be used as a tool to identify wells at risk. Moreover, a future sea level rise has been visualized and show that 3% of all wells on the island will get directly inundated along with 5% of the total land area. Important land such as urban areas, nature reserves, and animal protection areas will get inundated including the loss of environmental and socio-economic values. A precautionary approach needs to be implemented in future planning since many wells are already at risk of salinization. The complexity of the problem is vast, and this study aims to fill the gaps in literature and previous research in a more multi-criterion way. Nevertheless, the political discussion urgently needs to address the topic and a mitigation and adaptation strategy must be on the agenda.
125

Evaluating the Effects of Sea Level Rise on Sea Turtle Nesting Sites: A Case Study of the Archie Carr National Wildlife Refuge

Ussa, Melissa 29 March 2013 (has links)
The purpose of this thesis was to determine the extent of sea level rise (SLR) impact on sea turtle nesting beach habitat on Archie Carr National Wildlife Refuge (NWR) as well as impacts on management strategies. The Archie Carr NWR is of exceptional importance due to the high density of Loggerhead, Leatherback, and Green sea turtles that nest there in the summer months. GIS data provided by the Archie Carr NWR and various SLR scenarios, provided by both the Intergovernmental Panel on Climate Change (IPCC) as well as leading scholars, were used to determine inundation area loss across the Refuge as well as nearby parcels targeted for possible acquisition. Inundation losses for the six scenarios were calculated to be in the 20-25% range. Approximately 26% of current lower priority parcels are reclassified as high priority when integrating this information. Therefore, a significant revision to future acquisition strategies is recommended.
126

Methods for Coastal Flooding Risk Assessments : An Application in Iceland / Metoder för bedömning av översvämningsrisk från havet : En tillämpning på Island

Jóhannsdóttir, Guðrún Elín January 2019 (has links)
Flood risk increases with rising sea levels and coastal settlements need to adapt to this increasing risk. For that, hazard and risk assessments are an important step. Coastal floods have caused problems in Iceland in the past and are thought to do so in the future as well. Therefore, a coastal flooding risk as- sessment needs to be made for Iceland. A risk assessment is currently in the early steps of preparation and a fitting method needs to be developed. To facilitate the process, an overview of the methods used in neighbouring countries is provided here and the suitability of the methods for Iceland is discussed. Building on these methods, a coastal flood scenario is produced for both present and future conditions as a preliminary hazard assessment for the country. The scenario produced is an upper bound scenario, highly unlikely but still possible. As a result, flooded areas are mapped and areas that need to be studied further in regard to flood hazard and risk are identified. It is shown that hazard estimation can be per- formed for Iceland through scenario production and that scenario results can be used in risk assessments. / De nuvarande klimatförändringar i världen kommer påverka människor på många olika sätt. En av de många saker som förändras är havsnivån. Havsnivån har stigit allt snabbare sedan i början av 1900 talet och kommer nästan säkert att fortsätta stiga i flera århudraden. Förhöjda havsnivåer föl- jer ökad översvämningsrisk som vi måste anpassa oss efter (Church, Clark, et al., 2013). Därför är riskbedömningar, alltså systematiska förfarande för att värdera risk, viktiga så att passande förebyggande åtgärder kan användas för att minska negativa påverkan från havsöversvämningar. En bedömning av översvämningsrisk från havet fattas för Island men för närvarande förbereder Is- ländska Meteorologiska Byrån att genomföra en. En tillämplig method behövs hittas och för att un- derlätta arbetet beskrivas i denna rapport metoder för preliminära bedömningar av översvämningsrisk från några av Islands grannländer; Danmark, Norge, Sverige och Storbrittanien. I huvudsak använder alla dessa länder liknande metoder, även om de har olika fysiska förutsättningar. De använder statis- tiska återkomsttider från mareograf data och informationer om historiska översvämningar för att bedöma faran. Sårbarhet identifieras inom fyra sårbarhets klasser, ofta genom ett index. Till slut sammanställs faro- och sårbarhetskartor för att bedöma risken och utpeka områden med översvämningsrisk. Eftersom Island har inte tillräckligt mycket data för att använda samma metoder som grannländerna, produceras i den här rapporten ett scenario för att värdera översvämningsfaran. Scenariot bygger på idéer från grannländerna och ska vara osannolikt men möjligt. Det är beräknad för både nuvarande och framtida förhållanden. Genom att subtrahera landhöjden från scenario havsnivån är översvämningsdju- pet beräknat. Några områden vart vattnet sannolikt skulle flöda och måste vara grundligt forskade är identiferade. Många påverkande faktorer är inte inkluderade i scenariot och därför anger resultatet inte noggranna översvämningskartor utan grovt överblick över översvämningsfaran. Resultaten ger alltså en idé om vart faran från havsöversvämningar är som störst och i vilka områden framtidiga havsnivåförän- dringar kommer bli som största. De visar också att ett scenario kan användas för farobedömning på Island, som sen kan kombineras med sårbarhetsbedömning via en index för att bedöma översvämn- ingsrisken på samma sätt som i grannländerna.
127

Planning for sea level rise in Sweden : A study regarding how the parliamentary parties relate to climate change adaptation of sea level rise / Planering för havsnivåhöjning i Sverige : En studie angående hur riksdagspartierna arbetar med klimatanpassning av konsekvenser på grund av havsnivåhöjning

Emilia, Eriksson January 2019 (has links)
The consequences due to sea level rise are many, and will affect the environment and societies all around the world. There is uncertainty about how much and how quickly the sea will rise. Despite the uncertainties, society must be adapted to a changing climate. The climate change adaptation work is relatively new in Sweden, and there are still uncertainties about how this work should be carried out, and by whom. This thesis examines to what degree the Swedish parliament parties’ view on how to plan and adapt to sea level rise differ. The study is based on interviews with representatives from a majority of the political parties in the Swedish parliament. The results show that the interviewed representatives all agree that climate change and sea level rise are important issues to work with. The result also shows that the different parties have managed to agree on what they want to achieve, but not how or when it is best to implement adaptation measures towards sea level rise and other climate change-related effects. / Konsekvenserna av havsnivåhöjningar är många och kommer att påverka miljön och samhällen över hela jorden. Det råder osäkerheter om hur mycket och hur snabbt haven kommer höjas. Trots osäkerheterna så måste samhället anpassas till ett förändrat klimat. Klimatanpassningsarbetet är relativt nytt i Sverige och det råder fortfarande oklarheter om hur detta ska genomföras och av vem.   Uppsatsen undersöker i vilken utsträckning de svenska riksdagspartiernas åsikter angående planeringen och anpassningar till havsnivåhöjningen skiljer sig. Studien bygger på intervjuer med representanter från en majoritet av de politiska partierna i riksdagen. Resultaten visar på att de intervjuade representanterna alla håller med om att klimatanpassning är viktigt att arbeta med. Resultaten visar även på att de olika partierna har lyckats enas om vad man vill uppnå, men dock inte på vilket sätt man ska gå till väga eller när det är bäst att implementera åtgärder mot havsnivåhöjning och andra klimatförändringsrelaterade effekter.
128

Impacts of Sea-Level Rise on Urban Properties in Tampa Due to Climate Change

Xie, Weiwei 10 December 2021 (has links) (PDF)
The fast urbanization produces a large and growing population in coastal areas. However, the rise of sea level, one of the most significant impacts of global warming, makes coastal communities much more vulnerable to flooding than before. This Master’s thesis study investigates sea-level rise impacts on parcel-level property in the specific coastal city of Tampa, Florida, USA. An improved sea-level rise model based on satellite altimeter data is first used to predict future sea levels. Based on high-resolution LiDAR digital elevation data and property map, flooded properties are identified to evaluate property damage cost. This empirical analysis provides an in-depth understanding of potential flooding risks for individual properties with detailed spatial information at a fine spatial scale. The spatial and temporal analyses can be potentially used by researchers or governments to mitigate the impact of sea-level rise and make better urban management plans to adapt to climate change.
129

State of the environment and natural resources in Vietnam

Chu, Thi Thu Ha 25 August 2015 (has links)
Vietnam is considered as one of the countries having rich resources from forest and sea, with a high average annual rainfall. However, in view of IWRA, water volume per capita annually in Vietnam is lower than the standard for nations having water resources at average level. Vietnam was recognized by the World Wildlife Fund (WWF) as having three out of more than 200 biological zones of the world. Flora and fauna in Vietnam are very rich and abundant, but due to indiscriminate exploitation, along with weak management, biodiversity levels are significantly reduced. This is also one of the causes of environmental pollution and degradation in Vietnam, besides the impacts from production activities, population migration from rural areas to urban areas, rapid urbanization, climate change and sea level rise, etc. / Tảo đóng vai trò quan trọng trong mạng lưới thức ăn và chu trình sinh địa hóa của thủy vực và chúng chịu sự chi phối của nhiều yếu tố môi trường như ánh sáng, pH, nhiệt độ và dinh dưỡng. Nghiên cứu này trình bày đa dạng thành phần loài và biến động sinh khối thực vật phù du tại hồchứa Hòa Bình từ tháng 3 đến tháng 12 năm 2011. Các mẫu thực vật nổi được thu thập hàng tháng tại 4 điểm. Kết quả đã xác định được 6 lớp tảo chính bao gồm: Vi khuẩn lam, tảo lục, tảo silic, tảo mắt, tảo giáp và tảo lông roi hai rãnh. Nhóm tảo silic và Vi khuẩn lam chiếm ưu thế với độ phong phú tương đối là 61% và 32% tương ứng trong quần xã thực vật nổi. Vi khuẩn lam dạng tập đoàn và dạng sợi (Microcystis aeruginosa, M. wesenberg, Oscillatoria sp. tương ứng) chiếm ưu thế trong quần xã thực vật nổi vào các thời điểm đầu hè và mùa thu (tháng 4 và tháng 9). Tổng mật độ tế bào thực vật nổi dao động từ 84210 đến 100 x106 cell/L. Mật độ thực vật nổi biển động theo mùa với sinh khối tê bào cao vào đầu hè và mùa đông (tháng 4 và tháng 12) và sinh khối tếbào thấp vào các mùa hè và thu (tháng 6 đến tháng 10).
130

Sea-Level Rise and Climate Justice for Native Americans and Indigenous Peoples: An Analysis of the United States' Response and Responsibilities

Swiersz, Sarah 01 January 2020 (has links)
Sea-level rise and inland flooding driven by climate change threaten the health, economic development, and social stability of Native American Tribes and Indigenous Nations. Further, loss of traditional lands threatens the cultural practices and ties to heritage that provide ontological grounding for many Indigenous Peoples. While the Federal Trust Doctrine implies a responsibility for federal policy to aid Tribes by compensating them for impacts of sea-level rise, there is no legislation securing compensation for Indigenous Nations not recognized as Tribes. Due to the incommensurable nature of the damage to Native American and Indigenous communities who lose their lands to sea-level rise, any processes of compensation must transcend relocation measures and monetary transactions. Further, to combat aid programming that perpetuates the social, legal, and cultural disenfranchisement of Native Americans and Indigenous Peoples, legislation for compensation must endorse and empower Tribes’ and Nations’ autonomy by meaningfully including their insights. This study records the perspectives of members of the Seminole and Miccosukee Tribes and Gullah/Geechee Nation on climate change in the Southeastern U.S., specifically, sea-level rise washing out ancestral lands. This study’s ultimate purpose is to understand how Tribe and Nation members perceive the response and responsibility of the U.S. government in these situations. This study also presents a legal/political analysis of climate justice in these contexts, an exploration of Truth and Reconciliation Commissions as a mechanism for climate justice, and culminates in a policy proposal regarding climate justice for Native Americans and Indigenous Peoples.

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