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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.
41

A Decision Support Tool to Assess and Prioritise Project Drawdown Solutions at the Local Level

Lopez Cuadros, Laura, Rustamov, Elshan, Slob, Wietse, Stange, Daniela January 2020 (has links)
This thesis analyses how public decision-makers can rapidly and sustainably decarbonise their regions, considering the challenge that promoting timely decarbonisation represents. The research was divided into three phases and developed using desk studies and interviews with Project Drawdown (PD) experts, Swedish public officials and researchers. In phase one, PD solutions showed a shortcoming in sustainable operationalisation of global decarbonisation solutions. It was found that they alone could not account for sustainability, and that there is dependency on the context of application and on decision-making processes. In phase two, it was found that sustainability could be embedded in decision-making for decarbonisation through decision support. In the Blekinge example case, several challenges were found, for which sustainable decision support was needed. To respond to this challenge, a Decision Support tool (DST) was created, based on multi-criteria decision analysis. This three-step generic tool provides a relevance assessment to prove the suitability of decarbonisation solutions in the given context, a sustainability assessment to address sustainability challenges, and a prioritisation step for strategic decision-making. The tool was validated to be useful by Swedish policymakers and by international experts. This DST has the potential to support policy-making around the world to decarbonise regions rapidly and sustainably.
42

Hantering av extrem nederbörd i Örebro och Göteborg : En jämförande studie / Extreme precipitation management : A comparative study of Örebro and Gothenburg

Leppänen, Elsa, Koistinen, Johanna January 2022 (has links)
Climate changes are causing extreme weather conditions, which is expected to increase. Extreme precipitation is an example of this, which, through flooding, affects humans and buildings. This study aims to investigate how management of extreme precipitation takes place in two Swedish municipalities, the city of Gothenburg and Örebro municipality. Based on a thematic analysis of qualitative interviews with employees in the municipalities and document analysis of the municipalities' strategic planning documents, this study takes shape. The theoretical approach is based on what the existing research considers to be the most successful strategic, practical and organizational approaches. The result of this study shows that there is a need for better knowledge and clearer regulations regarding the management of extreme precipitation. The municipalities have come further in the work with strategic planning than with practical measures. Multifunctional facilities are a priority and, based on the study material, is the most effective way to implement practical measures.
43

DIRECT AIR CAPTURE CONTRIBUTION TO SUSTAINABLE DEVELOPMENT

Snorradóttir, Hólmfrídur January 2022 (has links)
To meet ambitious climate goals, of keeping global warming below 2°C, past emissions need to be removed from the atmosphere with the help of negative emissions technologies (NETs). The transition of energy systems, however, needs to follow the requirements of sustainable development to benefit all three pillars of sustainability, those are the environment, society, and economy. A NET that has gained increased attention from policymakers and businesses in recent years is direct air capture (DAC). The technology is currently on a small scale and faces challenges for scale-up such as energy and water intensity, the unclear requirements of resources and uncertain environmental, social, and economic impacts. The aim of this study was, therefore, to address DAC's impact on the three pillars of sustainability to answer the research question: How does direct air capture influence or connect to the three pillars of sustainable development? Because of the lack of research on DAC in connection with sustainability a qualitative interview approach was chosen where five interviews were conducted with researchers working with DAC. The findings derived from the interviews were separated into the different pillars of sustainability. The finding for the sustainability aspect included the definition of sustainability, various justice aspects and contributions to the SDGs. For the environmental aspect, DAC's carbon footprint and impact on mitigation were highlighted. The economic aspect of DAC showed the need for a clear business model and a supportive carbon mechanism. Lastly, for the social aspect low level of knowledge and the importance of social acceptance were recognized. Concluding, these different aspects influence the pillars of sustainability and need to be considered before further scale-up of DAC.
44

Grain Size Analysis of Late Pleistocene Loess Deposits, Jersey / Kornstorleksanalys av lössjord från övre pleistocen, Jersey

Edlund, Joakim January 2022 (has links)
As the world faces the effects of rapid climate change it is essential that we understand how the Earth’s climate has evolved in recent geological history. The island of Jersey harbours loess deposits which hold clues to recent climate change which have not been extensively studied. In this study, grain size analysis was employed on loess from the site of La Motte in order to shed light on climate change in the region during the last glacial. Several metrics such as the ratio of coarse to fine silt, the rate of deposition and the formation of ancient soils was used to assess the climate conditions during the time of deposition. The results show that the loess of La Motte is coarse compared to typical European loess but similar in grain size distribution to other sites along the English Channel, with relatively high amounts of sand and low amounts of clay. The relative coarseness of the deposits suggests a cold and dry depositional environment as well as proximity to the source of sediment and high wind intensities during the time of deposition. The fraction of coarse silt to fine silt, along with the rate of deposition and the occurrence of soil formation across the stratigraphy indicates that the climate slowly cooled from around 55 000 to 24 000 years ago when a sudden cooling event took place, then warmed until about 16 800 years ago where the climate suddenly cooled again. The timing of these rapid climatic shifts appears to correspond with Heinrich events 1 and 2 when large masses of ice were discharged from continental ice sheets. / Medan världen står inför effekterna av snabba klimatförändringar är det väsentligt att vi förstår hur jordens klimat har utvecklats under den senaste geologiska tiden. Ön Jersey hyser lössavlagringar som håller ledtrådar om den senaste tidens klimatförändringar och som inte studerats har studerats omfattande. I denna studie användes kornstorleksanalys på löss från lokaliteten La Motte med avsikt att utöka kunskapen om klimatförändringar i regionen under den senaste nedisningen. Ett flertal mått så som förhållandet mellan grov och fin silt, depositionshastigheten och bildningen av gamla jordar användes för att bedöma klimatförhållandena under avsättningstiden. Resultatet visar att La Mottes löss är grov jämfört med europeiska lössjordar, men i kornstorleksdistribution lik med andra lokaliteter längs med Engelska kanalen med relativt höga mängder sand och låga mängder lera. Avlagringarnas relativa grovhet tyder på en kall och torr avsättningsmiljö såväl som närhet till sedimentkällan och höga vindstyrkor under avsättningstiden. Förhållandet mellan grov och fin silt, tillsammans med depositionshastigheten och förekomsten av jordbildning genom stratigrafin tyder på att klimatet långsamt kyldes ner från omkring 55 000 år sedan till 24 000 år sedan då en plötslig nedkylning skedde. Klimatet värmdes sedan upp fram till omkring 16 800 år sedan då klimatet plötsligt kyldes ner igen. Tidpunkterna då dessa snabba avkylningar skedde verkar korrespondera med Heinrich-händelserna 1 och 2 då stora ismassor lossades från kontinentala istäcken ut i Nordatlanten.
45

Towards a Sustainable Resource Management : A Broader Systems Approach to Product Design and Waste Management

Singh, Jagdeep January 2013 (has links)
Rapid economic growth, urbanisation and increasing population have caused (materially intensive) resource consumption to increase, and consequently the release of large amounts of waste to the environment. Numerous technological and operational approaches to resource management have been introduced throughout the system of production, consumption and waste management. This thesis concludes that the current, rather isolated, efforts to influence different systems for waste management, waste reduction and resource management are indeed not sufficient from a long-term sustainability perspective. To manage resources and waste sustainably, resource management requires a more systems-oriented approach, which addresses the root causes of the problems. This thesis identifies and discusses different sustainability challenges facing the global waste management system. To address these challenges a broader systems approach to waste management is proposed. The thesis argues that there is a need to recognise the multitudes of perspectives, cross-scale dynamics and actors’ interactions at various levels. The barriers and limitations to a systems-oriented management of waste generation including design, production, consumption and waste management are discussed. The study utilises soft systems methodology (by Checkland (2000)) within which different concepts and methods are utilised to present a worldwide view on resource dynamics and develop a research heuristic for sustainable resource management. The study emphasises the need for a shared vision among various actors across the chain of production and consumption. To assist better planning, the need for improved databases on resource use and wastes is emphasised. / <p>QC 20140211</p>
46

Precipitation variability modulates the terrestrial carbon cycle in Scandinavia / Variation i nederbörd styr den terrestra kolcykeln i Skandinavien

Ek, Ella January 2021 (has links)
Climate variability and the carbon cycle (C-cycle) are tied together in complex feedback loops and due to these complexities there are still knowledge-gaps of this coupling. However, to make accurate predictions of future climate, profound understanding of the C-cycle and climate variability is essential. To gain more knowledge of climate variability, the study aims to identify recurring spatial patterns of the variability of precipitation anomalies over Scandinavia during spring and summer respectively between 1981 to 2014. These patterns will be related to the C-cycle through changes in summer vegetation greenness, measured as normalized difference vegetation index (NDVI). Finally, the correlation between the patterns of precipitation variability in summer and the teleconnection patterns over the North Atlantic will be investigated. The precipitation data was obtained from ERA5 from the European Centre for Medium-Range Weather Forecasts and the patterns of variability were found through empirical orthogonal function (EOF) analysis. The first three EOFs of the spring and the summer precipitation anomalies together explained 73.5 % and 65.5 % of the variance respectively. The patterns of precipitation variability bore apparent similarities when comparing the spring and summer patterns and the Scandes were identified to be important for the precipitation variability in Scandinavia during both seasons. Anomalous events of the spring EOFs indicated that spring precipitation variability had little impact on anomalies of summer NDVI. Contradictory, summer precipitation variability seemed to impact anomalies of summer NDVI in central- and northeastern Scandinavia, thus indicating that summer precipitation variability modulates some of the terrestrial C-cycle in these regions. Correlations were found between a large part of the summer precipitation variability and the Summer North Atlantic Oscillation and the East Atlantic pattern. Hence, there is a possibility these teleconnections have some impact, through the summer precipitation variability, on the terrestrial C-cycle. / Förändringar och variation i klimatet är sammankopplade med kolcykeln genom komplexa återkopplingsmekanismer. På grund av denna komplexitet är kunskapen om kopplingen mellan klimatvariation och kolcykeln fortfarande bristande, men för att möjliggöra precisa prognoser om framtida klimat är det viktigt att ha kunskap om denna koppling. För att få mer kunskap om klimatvariation syftar därför denna studie till att identifiera återkommande strukturer av nederbördsvariation över Skandinavien under vår respektive sommar från 1981 till 2014. Dessa relateras till förändringar i sommarväxtlighetens grönhet, uppmätt som skillnaden i normaliserat vegetationsindex (NDVI). Även korrelationen mellan sommarstrukturerna av nederbördsvariationen och storskaliga atmosfäriska svängningar, s.k. "teleconnections", över Nordatlanten undersöks. Nederbördsdatan erhölls från ERA5 analysdata från Europacentret för Medellånga Väderprognoser och strukturer av nederbördsvariationen identifierades genom empirisk ortogonal funktionsanalys (EOF) av nederbördsavvikelser. De tre första EOF av vår- respektive sommarnederbördsavvikelser förklarade tillsammans 73,5 % respektive 65,5 % av nederbördsvariationen. Strukturerna av nederbördsvariation under vår respektive sommar uppvisade tydliga likheter sinsemellan. Dessutom identifierades Skanderna vara av stor vikt för nederbördsvariationen i Skandinavien under båda årstider. Avvikande år av nederbördsvariation under våren indikerade att sagda nederbördsvariation haft liten påverkan på NDVI-avvikelser under sommaren. Emellertid verkade nederbördsvariationen under sommaren påverkat NDVI-avvikelser under sommaren i centrala och nordöstra Skandinavien. Detta indikerar att nederbördsvariationen under sommaren till viss del styr den terrestra kolcykeln i dessa regioner. För nederbördsvariationen under sommaren fanns korrelation mellan både Nordatlantiska sommaroscillationen och Östatlantiska svängningen. Det finns således en möjlighet att dessa "teleconnections" har en viss påverkan på den terrestra kolcykeln genom nederbördsvariationen under sommaren.
47

Estimating greenhouse gas emission via degassing and modeling temperature profiles in tropical reservoirs.

Wilson, Johan January 2020 (has links)
The aim of this project was to quantify the greenhouse gas (GHG) emissions from the degassing process ofhydroelectrical reservoirs in tropical regions.Reservoirs represent 25 % of the total area of man-made freshwater systems and are a source of GHG emissions tothe atmosphere. There are plans to construct an additional ca 3700 medium and large hydropower dams with theaim to double the current global energy production by hydropower. The majority of these are planned to be constructed in tropical regions. By understanding the processes controlling GHG emissions from these hydropowerreservoirs, the design of new hydropower plants can be developed to minimize the emissions.This project were designed to investigate GHG emissions from the turbines of two reservoirs in Brazil, as partof the larger ”Hydrocarb” project that investigates the total emissions from a number of reservoirs in Brazil. Toestimate the GHG emissions from the degassing process, a sampling campaign in the reservoir Chapeu D’Uvaswas conducted in April 2020 .Water samples from the entire water column at the water inlet, and directly afterthe dam were taken by using a sampling technique that involved a newly developed deep-water sampler. Themethane concentration was then analyzed for each depth of the water column and in the water directly after theoutlet. The results showed that at the deep layers with low oxygen concentration in the water column containedhigh concentrations of methane. These high methane concentrations were also found in the water at the outlet.This method was also planned to be used for the hydropower reservoir Funil, but due to the global COVID-19pandemic the campaigns were canceled. A modeling approach was instead constructed with the aim to modelthe methane concentration at the intake of the water in Funil, and to estimate the degassing as the water passesthe turbines. The first stage of this modeling approach was made within this study, where temperature profiles ofthe reservoir were modeled. The predicted profiles matched the observed temperatures profiles with a root meansquare error of 1.5 ◦C. The study concluded that the method of collecting methane concentrations throughout thefull water profile using the sampler were successful and can be used to examine methane concentration at the levelof the water inlet in reservoirs. The methane emission from the outlet at Chapeu D’Uvas was estimated to below contributing to 1.1 % of the total greenhouse gas emissions from the reservoir. For the modelling of methaneconcentration in water columns, the first part of the method to model daily temperature profiles that can be usedto implement empirical models of oxygen demand and methane production in the model.
48

CLIMATE CHANGE AND THE ELECTRICAL DISTRIBUTION GRIDS OF GOTLAND AND KLINTEHAMN

Brinkhurst, Sean January 2023 (has links)
Climate change represents a critical threat to electrical infrastructure. With reliance on electricity expected to increase in Sweden due to the transition from fossil fuel based energy to greener energy sources, it is important that the reliability of the electrical grid be upheld. This thesis studies the potential climate affected effects of extreme precipitation, annual average temperature change, water pooling after 100/500-year rains, and sea level rise. The RCP scenarios used for extreme precipitation and temperature change are RCP 4.5 and RCP 8.5. These climate effects will be studied in this thesis to understand and determine the extent of the climate effects on the electrical grid of Gotland and Klintehamn. The possible issues on infrastructure that can be exacerbated by these climate effects will be presented. This thesis will use spatial analysis to find results using GIS as a tool. GIS will be used to compare the various climate effects over the electrical grid data. Data was received from various sources, extreme precipitation and temperature change were sourced from SMHI, water pooling, and sea level rise were sourced with permission from Region Gotland. The electrical grid data for both Gotland and Klintehamn was received from GEAB, this data is considered nationally sensitive information therefore the location of this data is not shown. The results generally show that climate change, no matter the scenario presents a threat to the infrastructure. Although it should be noted as well that the scenario will impact the severity of the effects. RCP 8.5 will likely have more of an effect for both extreme precipitation and temperature than RCP 4.5. Water pooling is expected to have a greater effect on the &lt;20kV lines than on the 70kV infrastructure. Finally, sea level rise is expected to have a much greater effect from 2-meter sea level rise over the 1-meter sea level rise. The overarching theme found is that climate change will have impacts over the electrical grid.
49

CLIMATE FINANCE AND UNIVERSAL ENERGY ACCESS: ENERGY JUSTICE IN THE GREEN CLIMATE FUNDS PROJECTS TO PROMOTE ENERGY ACCESS IN AFRICA

Sjölén, Alice January 2023 (has links)
Climate finance is becoming an increasingly important aspect of climate change action, and massive sums are estimated to be required to mitigate further increase in greenhouse gas (GHG) emissions. Mitigation projects supported by climate finance further have the possibility to increase access to modern energy services in countries where these are lacking. Focusing on the Green Climate Fund (GCF) and the fund’s climate finance projects committed to enhancing energy access, this study investigates the complexities related to climate finance projects and what possible justice implications climate finance might result in. The area of focus in the study is the African continent, and the aspect of energy justice, specifically energy access equity. The study uses qualitative document analysis and reflexive thematic analysis along with an energy justice lens and framework, to analyse aspects of energy justice in six approved funding proposals of the GFCs energy generation and access portfolio. The results reveal three major overarching themes of a strong focus on private sector enhancement, where risk management and return on investments are common patterns in the approved funding proposals, site selection criteria that focus on financial viability and market potential, and a strong focus on finding a balance between affordability and profits. Resulting from this is likely to be an enhancement of energy access for the middle and low-income population in Africa, however, the results of the study show that energy justice implications resulting from the planned projects, particularly in terms of energy access equity are likely to arise. The themes found in the documents are likely to result in both distributive and recognition justice implications specifically affecting individuals, households and social groups living in extreme poverty or in areas deemed as undesirable for investments. It further highlights the need to consider already marginalised groups in society and not only financial viability of projects to attract private sector involvement. The study concludes that while private finance is positive in terms of climate finance, a balance between private and public finance is of importance, and increased focus must be put on the fairness and equity of energy access projects supported by climate finance from the Green Climate Fund.
50

Energy-saving impacts of intelligent speed guidance at signalized intersections for different driver behaviors and vehicle powertrains / Energibesparande effekter av intelligent hastighet vägledning vid signaliserade korsningar för olika förarbeteenden och fordonsdrivlinor

Yang, Yuxuan January 2022 (has links)
In order to control the energy consumed by vehicles for crossing signalized intersections, this project designs and tests a speed guidance energy-saving strategy for signalized intersections, taking drivers’ bounded rationality into consideration. This research achieves speed guidance by developing theoretical foundation of speed guidance, dividing scenarios for practise of speed guidance, and calculating optimal trajectories for vehicles. As for influence of bounded rationality, this research categorizes all drivers into three different types: aggressive drivers, normal drivers and conservative drivers. Numerical simulation of this research is focuses on a single intersection, with three traffic saturation level, represented by 346, 519 and 692 vehicles per hour. Considering the foreseeable popularization of electric cars (EV) in the close future, proportion of EV is also taken as a variable, and experiments are carried separately at three milestones of EV proportion: 0%, 30%, and 60%. The findings suggest that aggressive drivers benefit the most from the speed guidance in energy saving, and speed guidance does lest benefit to normal drivers. Both drivers’ bounded rationality and high traffic volume could lead to increase of energy consumption, while providing specifically modified speed guidance is able to achieve satisfying reductions to these effects. With increase of EVs’ proportion in the traffic flow and drop of overall energy consumption, effect of the guidance becomes comparatively worse than the previous non-EV performance of 7% to 11%, while remaining to be effective to cut off overall energy consumption by 5% to 8%. This research is able to improve normal speed guidance with more accurate and practicable guidance information for drivers in current traffic environment.

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