Dissertations / Theses: '040104 Climate Change Processes'

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Chin-Yee, Simon. "Defining climate policy in Africa : Kenya's climate change policy processes." Thesis, University of Manchester, 2018. https://www.research.manchester.ac.uk/portal/en/theses/defining-climate-policy-in-africa-kenyaas-climate-change-policy-processes(3b7440d0-7f08-4e87-b47d-ea4ad0a56d50).html.

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This thesis seeks to investigate what shapes climate change policies in Kenya. Using Peter Haas' concept of usable knowledge, it argues the need to move beyond conventional perspectives on knowledge and power and provides a framework for understanding what knowledge and mechanisms are usable for policy makers. I argue that Kenyan climate policy is shaped by the interaction of knowledge and power across three crucial levels of influence - global, regional and national. As climate change forces us to rethink how we combine economic policies with environmental realities in Africa, each level encompasses distinct policy narratives where critical actors have an impact on national climate change policy. First, I argue that the standards, norms and regulations established by the global climate regime are directly reflected in national climate strategies of African countries, not only in terms of diplomatic moves to adhere to commitments made, but also in respect to benefiting from international mechanisms put in place to aid developing countries. Second, I examine the One Voice, One Africa narrative. This looks at the rise of the African Group of Negotiators within the global climate regime and their ability to influence Kenyan policy. Third, Kenya's climate change policy is shaped by the interaction of economic, political, and environmental constructs in national policy-making. The principle goal of this thesis is to open African environmental scholars and climate change policy analysts to a rigorous and flexible questioning of how climate policy processes operate in the African context.

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A'Bear, Andrew Donald. "Climate change, fungus-invertebrate interactions and ecosystem processes." Thesis, Cardiff University, 2014. http://orca.cf.ac.uk/58513/.

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Saprotrophic fungi are the main agents of primary decomposition and nutrient cycling in woodland ecosystems. Powerful enzymatic capabilities enable then to break down the most recalcitrant components of wood and leaf litter, such as lignin and cellulose. Nutrients are retained by dynamic networks of mycelium, which are vulnerable to grazing by soil invertebrates. The studies reported in this thesis employed laboratory microcosm, mesocosm and field manipulations to further mechanistic understanding of climate change effects on basidiomycete fungal-dominated woodland decomposer community dynamics and ecosystem processes. Increased mycelial growth at elevated temperature can be prevented by collembola grazing in soil microcosms. The strength of this top-down effect varied with fungal palatability, which had a bottom-up effect on collembola populations and their responses to warming. A mesocosm multispecies collembola population was more strongly regulated by the bottom-up effect of inoculation with cord-forming fungi than climate change (warming, in combination with soil wetting or drying). Collembola can graze fungal cords, but thickness and chemical defences make them less palatable than soil microfungi, which are outcompeted by basidiomycete mycelia. In the absence of fungal biomass limitation by collembola, abiotic conditions regulated microbial community functioning. Warming stimulated fungal-mediated wood decomposition, particularly in drier soils. Moisture was the most important determinant of enzyme activity and displayed an interaction with temperature analogous to that for wood decay. Macro-invertebrates, such as woodlice, are better able to exploit nutritious, but thick and defensive, fungal cords. The consequences of macro-invertebrate grazing for fungal-dominated microbial community function were tested in a field manipulation of woodlouse (Oniscus asellus, Isopoda) population densities, predicted to increase due to climate warming. This provides the first evidence for bottom-up effects of fungal palatability on woodlouse populations. Body lipid analysis revealed fungi as a major component of the generalist woodlouse diet. Despite low population densities at the site, altered O. asellus abundance influenced aspects of microbial community functioning. The importance of biotic effects on decomposition may be more heterogeneous than abiotic influences, depending on microbial community dominance and the abundance of key macro-invertebrate taxa.

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André, Karin. "Climate change adaptation processes : Regional and sectoral stakeholder perspectives." Doctoral thesis, Linköpings universitet, Tema vatten i natur och samhälle, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-90500.

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This thesis analyses how societal adaptation processes in public and private sectors at the regional to local level in Sweden are enacted. The thesis pays particular attention to critical factors that constrain or enable adaptation by focussing on: who are the stakeholders, how do different stakeholders perceive their capacity to adapt, and the role of stakeholder interaction in facilitating adaptation processes A combination of two analytical perspectives is used where one is based on key concepts within adaptation literature, and the other draws on boundary crossing and transdisciplinary knowledge production (stakeholders, adaptive capacity, and science-based stakeholder dialogues). The study is conducted within the scope of two overall case studies of local adaptation processes within an urban region, and a land-use based sector, the private forestry sector. The cases are setting the scene for the collection of empirical material which is achieved through qualitative methods, primarily focus groups discussions with local and regional, public and private stakeholders with an interest in, and responsibility for adaptation. The focus groups meetings are organized as a series of meetings to which different participatory techniques are applied. The study also builds on a comprehensive stakeholder mapping. First, the results suggest a systematic method for identifying stakeholders in adaptation research, policy, and planning applicable in both sectors and regions that combines top-down knowledge with experience and knowledge based on bottom-up processes. Second, the analysis of perceived adaptive capacities reveal several facilitating and constraining factors that relates both to the characteristics of climate risks, experience of climate variability and extreme weather events, and responsibility- and decision-making structures. Third, the analysis of the interaction between local experts and scientists show that there is potential for the boundary spanning function of science-based stakeholder dialogues in facilitating adaptation through stimulating questions and sharing different knowledge bases and experiences among the participants. However further attention needs to be taken to the institutional environment and the role of so called anchoring devices that help local experts to contextualise, discus and thus anchor scientific knowledge in their own decision-making context. In conclusion, there are both commonalities between adaptation processes in the two case studies and some marked differences, e.g., regarding the concept of adaptation, what type of adaptation actions that are identified, the perceived opportunities for adaptation and degree of complexity.
Denna avhandling analyserar hur klimatanpassningsprocesser inom privata och offentliga sektorer på regional till lokal nivå i Sverige initieras, utvecklas och genomförs. Avhandlingen ägnar särskild uppmärksamhet åt identifiering av vilka intressenter (”stakeholders”) som är involverade i att underlätta och genomföra anpassning, uppfattningar om anpassningsförmåga samt vilken roll interaktion mellan olika intressenter kan ha för att underlätta anpassning. En kombination av två analytiska perspektiv används som bygger på tidigare forskning om klimatanpassningsprocesser samt transdisciplinär kunskapsproduktion. Studien genomförs inom ramen för två övergripande fallstudier av anpassningsprocesser i en urban region samt den privata skogssektorn. Fallstudierna utgör grunden för insamlingen av det empiriska materialet som bygger på kvalitativa metoder. Den främsta metoden är fokusgruppsdiskussioner med lokala och regionala, privata och offentliga aktörer med intresse av, eller ansvar för klimatanpassning. Fokusgrupperna organiseras som en serie möten där olika deltagandetekniker tillämpas. Studien bygger också på en omfattande intressentkartläggning. I avhandlingen utvecklas och ges förslag på en stegvis metod för att identifiera intressenter för anpassningsprocesser som kan användas inom forskning och praktik. Studien analyserar också hur olika intressentgrupper upplever förmågan att hantera klimatförändringar. Ett antal möjliggörande och begränsande faktorer identifieras så som karaktären på de upplevda klimatriskerna, erfarenhet av klimatvariationer och extrema väderhändelser, samt ansvar- och beslutsstrukturer. Slutligen, analyseras om och i så fall hur interaktionen mellan lokala experter och forskare som deltar i intressantdialoger (”science-based stakeholder dialogues”) kan underlätta anpassning. Resultaten visar att det finns potential genom att deltagarna ges möjlighet att ställa frågor tillvarandra och dela med sig av sina olika kunskapsbaser och erfarenheter, samt utforska olika anpassningsalternativ. Däremot behövs vidare studier för att undersöka betydelsen av det institutionella sammanhanget samt hur olika verktyg (”anchoring devices”) kan bidra när det gäller att förankra och omsätta kunskap om klimatförändringar i olika beslutskontexter. Avslutningsvis visar denna studie på att det finns både likheter och skillnader i hur anpassningsprocesser kommer till uttryck bland de olika aktörsgrupperna inom fallstudierna, t.ex. när det gäller hur begreppet anpassning används, vilken typ av anpassning som identifieras, upplevda möjligheter för anpassning samt graden av komplexitet.

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Hsu, Po-Han. "Communicating climate change in Internet discussion fora : processes and implications." Thesis, University of East Anglia, 2014. https://ueaeprints.uea.ac.uk/48710/.

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Communicating climate change issues in the Internet era requires new strategies that incorporate online communication. The rapid growth of new media and widespread use of the internet has marked everyday lifestyles in modern society. Information on a wide range of social issues, including climate change, is disseminated and debated through online discussions in internet fora. In this research, communication on internet fora and other potential forms of online social interaction are explored, to identify ways to enhance climate change communication on the Internet. The thesis raises three research questions to explore the communication context of internet fora discussion, namely: what are characteristics of the communication process on internet fora? Who is involved in the communication process? What influences do these online communication activities have on users’ everyday activities? The research applies a mixed-methods approach of analysing the usage of Internet fora and the contents of fora communication activities to explore these questions. This includes qualitative reviews of topic-thread discussions to reveal users’ roles in discussions, as well as surveys of fora users. It is argued that with increasing levels of interaction among communicators (people who post or reply to articles in order to express or respond ideas) on internet fora, these communicators are mobilised to join the online discussion process, competing for opinion leadership. The online discussions further contribute to the formation of opinions on climate change, as climate change and related issues are discussed The thesis thereby aims to contribute to the development of effective approaches for opinion formation and climate change communication online, and to encourage individuals to discuss changing behaviour patterns and public engagement of greenhouse gas reduction actions.

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Pardikes, Nicholas A. "Global Change and Trophic Interaction Diversity| Complex Local and Regional Processes." Thesis, University of Nevada, Reno, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10282934.

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The structure and functioning of ecosystems across the globe are rapidly changing due to several components of global environmental change (GEC). My dissertation aims to illustrate how regional and local aspects of GEC impact diverse assemblages of species and species interactions. All organisms are embedded in complex networks of species interactions, and future efforts to predict and mitigate the impacts of GEC on ecological communities will be facilitated by such studies that incorporate a suite of species and species interactions. This study advances our understanding of how GEC will impact ecological communities by investigating two questions about GEC: 1) How will shifts in global climate cycles (e.g., El Nino Southern Oscillation), as a consequence of global warming, impact a diverse assemblage of butterflies that exist across a heterogeneous landscape? 2) What are the consequences of woody plant encroachment on complex, specialized interactions between plants, insect herbivores, and natural enemies (e.g., insect parasitoids)? Furthermore, I helped develop a tool to identify characteristics of ecological communities that are essential for promoting the diversity of trophic interactions. While the loss of species diversity is well recognized, interactions among species are vanishing at an astonishing rate, yet we know little about factors that determine the diversity of interactions within a community. Using data from a long-term butterfly monitoring dataset, I was able to demonstrate the utility of large-scale climate indices (e.g., ENSO) for modeling biotic/abiotic relationships for migratory butterfly species. Next, I used encroaching juniper woodlands in the Intermountain West to uncover that population age structure of dominant tress, such as juniper, can affect plant-insect dynamics and have implications for future control efforts in the expanding woodlands. Additionally, reductions of understory plant diversity, as a consequence of juniper expansion, resulted in significantly lower parasitism rates and parasitoid species diversity. Finally, simulated food webs revealed that species diversity and, to a lesser degree, consumer diet breadth, promote the diversity of trophic interactions. As ecosystems across the globe experience changes and the loss of species diversity continues, these findings offer insight into how GEC will impact species and species interactions.

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Villemain, Stéphane. "Statistical modeling of daily streamflow processes in consideration of climate change." Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=19279.

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Water resource planners need to develop contingency plans to deal with the potential impacts of climate variability and changes in the frequency and magnitude of riverflows. Recently, General Circulation Models (GCMs) have been recognized to be able to represent reasonably well the main features of the global atmospheric circulation for the current climate and could produce details of future climate conditions. This study is concerned with the development of statistical models that could describe accurately the linkage between large-scale GCM simulations and observations of the streamflow process at Eaton, Quebec, Canada. Such a linkage could be used to predict the resulting change of the selected streamflow characteristics from the projected change of climate conditions given by GCMs. These models are based on the application of linear regression methods to link historical streamflow data with climatic predictors at the daily scale as well as on the use of stochastic autoregressive modeling. Results of this numerical application have indicated that the combined regression-autoregressive model with log-normal random noise could provide accurate description of observed statistical daily flow properties at the study site. This model was then used to assess future streamflow conditions from CGCM1 (Coupled Global Climate Model from the Canadian Centre for Climate Modelling and Analysis, version 1) and HadCM3 (Hadley Centre Coupled Model, version 3) outputs for different climate change scenarios.
L'étude des impacts potentiels des changements du climat et de sa variabilité sur les ressources en eau demande de modéliser l'évolution future des débits de rivières. Les Modèles de Circulation Générale (GCMs) sont de récents outils qui fournissent une l'information fiable sur l'évolution future des variables atmosphériques. La présente étude a pour but de développer des modèles statistiques permettant de relier ces variables climatiques aux variables de débit. De tels outils permettraient d'obtenir de l'information sur l'évolution future des débits à partir des simulations GCM. Ces modèles sont fondés sur l'utilisation conjointe à l'échelle journalière de techniques de régression linéaires et de techniques stochastiques autorégressives. En particulier, le modèle combiné régression-autorégression avec une génération aléatoire lognormale de résidus donne des résultats satisfaisants. Ce modèle a été utilisé pour évaluer l'évolution future des conditions de débit en utilisant des scénarios de changement climatique CGCM1 (Modèle couplé climatique global du Centre Canadien de la modélisation et de l'analyse climatique, version 1) et HadCM3 (Modèle couplé du centre Hadley, version 3).

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Cung, Annie. "Statistical modeling of extreme rainfall processes in consideration of climate change." Thesis, McGill University, 2007. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=100788.

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Extreme rainfall events may have catastrophic impacts on the population and infrastructures, therefore it is essential to have accurate knowledge of extreme rainfall characteristics. Moreover, both the scientific community and policymakers have recently shown a growing interest in the potential impacts of climate change on water resources management. Indeed, changes in the intensity and frequency of occurrence of extreme rainfall events may have serious impacts. As such, it is important to understand not only the current patterns of extreme rainfalls but also how they are likely to change in the future.
The objective of the present research is therefore to find the best method for estimating accurately extreme rainfalls for the current time period and future periods in the context of climate change. The analysis of extreme rainfall data from the province of Quebec (Canada) revealed that, according to L-moment ratio diagrams, the data may be well described by the Generalized-Extreme-Value (GEV) distribution. Results also showed that a simple scaling relationship between non-central moments (NCM) and duration can be established and that a scaling method based on NCMs and scaling exponents can be used to generate accurate estimates of extreme rainfalls at Dorval station (Quebec, Canada). Other results demonstrated that the method of NCMs can accurately estimate distribution parameters and can be used to construct accurate Intensity-Duration-Frequency (IDF) curves.
Furthermore, a regional analysis was performed and homogenous regions of weather stations within Quebec were identified. A method for the estimation of missing data at ungauged sites based on regional NCMs was found to yield good estimates.
In addition, the potential impacts of climate change on extreme rainfalls were assessed. Changes in the distribution of annual maximum (AM) precipitations were evaluated using simulations from two Global Climate Models (GCMs) under the A2 greenhouse gas emission scenario: the Coupled Global Climate Model version 2 (CGCM2A2) of the Canadian Centre for Climate Modelling and Analysis, and the Hadley Centre's Model version 3 (HadCM3A2). Simulations from these two models were downscaled spatially using the Statistical DownScaling Model (SDSM). A bias-correction method to adjust the downscaled AM daily precipitations for Dorval station was tested and results showed that after adjustments, the values fit the observed AM daily precipitations well. The analysis of future AM precipitations revealed that, after adjustments, AM precipitations downscaled from CGCM2A2 increase from current to future periods, while AM precipitations downscaled from HadCM3A2 show a mild decrease from current to future periods, for daily and sub-daily scales.

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Liu, Liguang. "Understanding China’s Climate Change Mitigation Policy Development: Structures, Processes and Outcomes." FIU Digital Commons, 2011. http://digitalcommons.fiu.edu/etd/429.

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Climate change is one of the most important and urgent issues of our time. Since 2006, China has overtaken the United States as the world’s largest greenhouse gas (GHG) emitter. China’s role in an international climate change solution has gained increased attention. Although much literature has addressed the functioning, performance, and implications of existing climate change mitigation policies and actions in China, there is insufficient literature that illuminates how the national climate change mitigation policies have been formulated and shaped. This research utilizes the policy network approach to explore China’s climate change mitigation policy making by examining how a variety of government, business, and civil society actors have formed networks to address environmental contexts and influence the policy outcomes and changes. The study is qualitative in nature. Three cases are selected to illustrate structural and interactive features of the specific policy network settings in shaping different policy arrangements and influencing the outcomes in the Chinese context. The three cases include the regulatory evolution of China’s climate change policy making; the country’s involvement in the Clean Development Mechanism (CDM) activity, and China’s exploration of voluntary agreement through adopting the Top-1000 Industrial Energy Conservation Program. The historical analysis of the policy process uses both primary data from interviews and fieldwork, and secondary data from relevant literature. The study finds that the Chinese central government dominates domestic climate change policy making; however, expanded action networks that involve actors at all levels have emerged in correspondence to diverse climate mitigation policy arrangements. The improved openness and accessibility of climate change policy network have contributed to its proactive engagement in promoting mitigation outcomes. In conclusion, the research suggests that the policy network approach provides a useful tool for studying China’s climate change policy making process. The involvement of various types of state and non-state actors has shaped new relations and affected the policy outcomes and changes. In addition, through the cross-case analysis, the study challenges the “fragmented authoritarianism” model and argues that this once-influential model is not appropriate in explaining new development and changes of policy making processes in contemporary China.

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Capell, René. "Modelling dominant runoff processes using tracers and landscape organisation in larger catchments." Thesis, University of Aberdeen, 2011. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=186120.

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This work has contributed to the understanding of dominant runoff generation at the large catchment scale and to the understanding of the relationships between landscape properties and hydrological behaviour. The developed models were used to estimate the climate change impact on the hydrology in the study catchment. A multivariate geochemical tracer survey was carried out in North Esk catchment in north east Scotland. A generic typology was developed using multivariate statistical methods to characterise the hydrochemical tracer response. Upland headwater runoff was dominant downstream in winter and provided significant flows during base flow periods in summer. These insights were complemented by a conjunctive analysis of long-term river flow data and a one year stable isotope survey. Integrative metrics of transit times, hydrometric responses, and catchment characteristics were explored for relationships at the large catchment scale. The evaluation that the associated soils and bedrocks, themselves controlling the flow path distribution, have a strong influence on the integrated hydrological catchment response. The empirically-based understanding of dominant runoff generation processes in the North Esk uplands and lowlands were used in a stepwise rainfall-runoff model development. Tracers were directly incorporated to reduce structural and parameter uncertainty. The integration of tracers helped reduce parameter uncertainty. These tracer-aided models increased confidence for using them to explore the effects of environmental change. Climate change impacts in the catchment where explored by forcing the models with projected climate change forcing from the UK Climate Projections 2009. The results revealed landscape-specific changes in the hydrological response with increased summer drought risk in the lowlands and diminishing snow influence and increased winter floods in the uplands. The spatial integration mediated the extremes observed in the subcatchments.

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Pathack, Beenay M. R. "Modulation of South African summer rainfall by global climatic processes." Doctoral thesis, University of Cape Town, 1993. http://hdl.handle.net/11427/21735.

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Global climatic processes which control the interannual variability of summer rainfall over South Africa are studied. Monthly and seasonal rainfall variations are analysed with respect to fluctuations in sea surface temperature (SST), outgoing longwave radiation (OLR) and tropospheric winds. OLR is used as a proxy for convective intensity and for the identification of areas of sympathy and opposition to convection over South Africa. Wind data (and derived parameters) are employed to explore large- scale tropical dynamical structures. Plausible explanations are offered for the observed associations. A change in sign of the correlation structure from the October/November rainfall regime to the December through March regime is indicative of a shift from downstream advective processes (Atlantic side) to a teleconnection-type of behaviour (Indian Ocean side). Rainfall variations during the late summer months show significant (and negative) links with SST fluctuations within the equatorial/tropical Pacific and Indian Ocean areas and are consistent with results obtained in analyses with respect to OLR fluctuations. December OLR in the Western Equatorial Indian Ocean is associated with a large portion of the variance in late summer rainfall, and points to a possible relation with the evolution of the Indian monsoon. The positive association implies that reduced cloudiness off the eastern coast of equatorial Africa in the spring precedes above normal mid- and late- summer rainfall over South Africa. Vertical mass overturnings are investigated through the velocity potential and derived parameters (the Zonal Circulation and Meridional Circulation Indices). The results suggest that the vertical tropospheric cells are among the important associated components which modulate climate across southern Africa, and that broad scale flows have an impact upon regional circulation cells. Evaluation of the vertical circulations with respect to wet and dry composites reveals that the Walker-type cell which connects a branch over the Indian Ocean gradually forms after November and reaches peak development in February. A slight increase of SST in the Central Equatorial Indian Ocean (CEI) modifies the Walker cell anomaly leading to below normal summer rainfall over South Africa. Additional thermodynamic inputs in the CEI region are conducive to deeper convection, hence elevated outflow signatures are observed in the velocity potential and related fields. It is conjectured that the teleconnections between South Africa, the CEI and the remote Pacific Ocean regulate the depth of moisture influx and convergence over South Africa. Based on the results of this study, it is believed that empirical models could be designed for long-range prediction of summer rainfall anomalies over the central interior of South Africa.

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Asdar, Sarah. "Climate change impact on ecosystems of Prince Edward Islands: role of oceanic mesoscale processes." Doctoral thesis, Faculty of Science, 2019. http://hdl.handle.net/11427/30330.

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The subantarctic Prince Edward Islands (PEIs, 47◦S-38◦E) are classified as isolated and hostile regions, in which the terrestrial and marine ecosystems are relatively simple and extremely sensitive to perturbations. The island’s location, between the Subantarctic Front (SAF) and the Polar Front (PF), bordering the Antarctic Circumpolar Current (ACC) provides an ideal natural laboratory for studying how organisms, ecological processes and ecosystems respond to a changing climate in the Southern Ocean. Recent studies have proposed that climate changes reported at the islands may correspond in time to a southward shift of the ACC and in particular of the SAF. This southward migration in the geographic position of major ocean fronts is likely to coincide with dramatic changes in the distribution of species and total productivity of this region. However, there are other sources of variability in the hydrodynamic conditions around the PEIs: upstream of the islands, at the South West Indian Ridge (SWIR), a region of high eddy kinetic activity produces mesoscale features that directly irrigate the PEIs and may impact their marine environment. Based on satellite altimetry in that region, the positions of the SAF and PF were found to be highly variable at interannual and monthly time scales. They also revealed a significant long-term southward trend which was highlighted at the Southern Ocean scale. The mesoscale activity also showed an interannual and intra-annual variability and a decrease in eddy kinetic energy over 24 years was observed in the region. At a more local scale, we highlighted that the archipelago’s environment was impacted by the mesoscale features produced at the SWIR. The temperature, the mixed layer and velocities recorded between the islands were clearly affected by the eddies passing in the vicinity of the PEIs. Moreover, a large signal dominating the main current time series appeared to be a tidal signal, another important driver of variability of the circulation in between the two islands. On a second hand, an idealised model configuration was designed for the PEIs region to study the mesoscale eddy properties and the physical mechanisms of their formation at the ridge. The Eddy Available Potential Energy revealed a maximum of energy around 800 m depth, confirming the deep reaching characteristic of the eddy originated in the region and suggested the presence of a local energy source at this depth. This eddies activity was shown to be the result of a combination of barotropic and baroclinic instabilities occurring at the ridge. Finally, we investigated on the potential consequences of a southward shift of the SAF in the region of the islands. Because the model was idealised, it allowed us to simulate an SAF southward shift by shifting the initial and boundary conditions. The main result was the clear decrease of mesoscale activity in the region which could potentially impact the ecosystems of the PEIs.

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Lee, Min Young. "Statistical modeling of extreme rainfall processes in the context of climate change." Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=114421.

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The occurrence of extreme storms is a critical consideration in the design and management of a large number of water-resource projects. In current engineering practice, the estimation of extreme rainfalls is accomplished based on statistical frequency analysis of maximum precipitation data. The objective of this frequency analysis is hence to estimate the maximum amount of precipitation falling at a given point for a specified duration and return period. Results of precipitation frequency analysis are often summarized by "intensity-duration-frequency" (IDF) relationships for a given site. However, traditional methods in the development of IDF relations have two major limitations. Firstly, these existing methods were not able to account for the extreme rainfall characteristics over different time scales. Secondly, these traditional methods cannot take into account the potential impacts of climate variability and climate change. Therefore, the main objective of the present study is to propose an improved method for extreme rainfall estimation that could overcome these limitations. The proposed method was based on the scale-invariance GEV distribution and the statistical downscaling procedure to construct the IDF relations in the context of climate change. The Non-Central Moment method was used for the estimation of the three parameters of the GEV. Results of a numerical application using Annual Maximum Precipitation (AMP) data from a network of 14 rain-gauge stations in South Korea has indicated the feasibility and accuracy of the suggested method. In particular, the observed AMP series displayed a simple scaling behaviour. In addition, the linkages between global climate variables given by two Global Climate Models (GCMs) (one from Environment Canada and one from the UK Hadley Centre) and the local extreme rainfall characteristics have been successfully established for predicting the resulting changes of the IDF relations under different climate change scenarios A2, A1B, and B2. It was found that the IDF relations for future periods (2020's, 2050's, and 2080's) showed increasing or decreasing trends depending on the GCM used and the climate scenario considered.
La fréquence des tempêtes extrêmes est un facteur critique dans la conception et gestion d'un grand nombre de projets de ressources en eau. Dans la pratique courante, l'estimation des pluies extrêmes est réalisée en se basant sur l'analyse de fréquence statistique des données de précipitations maximales. L'objectif de cette analyse de la fréquence est donc d'estimer le montant maximal de précipitations qui tombent à un moment donné pendant une durée déterminée, ainsi que la période de retour. Les résultats de l'analyse de la fréquence des précipitations sont souvent résumés par les relations Intensité-Durée-Fréquence (IDF) pour un site donné. Toutefois, les méthodes traditionnelles dans le développement des relations IDF ont deux limites majeures. Tout d'abord, ces méthodes n'ont pas été en mesure de tenir compte des caratéristiques des précipitations extrêmes sur des différentes échelles de temps. Deuxièmement, ces méthodes traditionnelles ne tiennent pas compte des impacts potentiels de la variabilité climatique et du changement climatique. Par conséquent, l'objectif principal de cette présente étude est de proposer une méthode d'estimation des précipitations extrêmes améliorée qui pourrait surmonter ces limitations. La méthode proposée a été basée sur l'échelle d'invariance de distribution GEV et la procédure de réduction d'échelle statistique pour construire des relations IDF dans le contexte du changement climatique. La méthode des moments non-centraux a été utilisée pour l'estimation des trois paramètres de la GEV. Les résultats obtenus par une application numérique des données de Précipitations Maximales Annuelles (PMA) à partir d'un réseau de 14 stations pluviométriques en Corée de Sud ont démontré la faisabilité et la précision de la méthode proposée. La série de PMA observée a particulièrement affiché une propriété d'échelle simple. En outre, les liens entre les variables climatiques globaux donnés par les deux Modèles Climatiques Globaux (MCGs) (un en provenance d'Environnement Canada et l'autre du Centre Hadley du Royaume-Uni) et les caractéristiques des précipitations locaux extrêmes ont été établis avec succès pour prédire les changements qui résultent des relations IDF selon des différents scénarios climatiques - A2, A1B, et B2. Il a été constaté que des relations IDF pour les périodes futures (les années 2020, 2050, et 2080) ont démontré des tendances qui augmentent ou diminuent dépendemment des MCG utilisés et du scénario climatique à l'étude.

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Dowrick, David John. "Laboratory studies of biogeochemical processes in wetlands subject to simulated climate change." Thesis, Bangor University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.262748.

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Bennett, Kelly. "Evolutionary processes generating African biodiversity : a case study on Aedes mosquitoes." Thesis, University of Manchester, 2015. https://www.research.manchester.ac.uk/portal/en/theses/evolutionary-processes-generating-african-biodiversity-a-case-study-on-aedes-mosquitoes(155ae971-cb53-45fc-81f4-50a4db4fe46c).html.

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A central concept in evolutionary biology is to understand how new species arise and are maintained. Studying the temporal and spatial distribution of genealogical lineages provides insight into evolutionary processes which govern diversification while the study of disease vectors has additional implications for human health. Within Africa, medically important Aedes mosquitoes provide an interesting case in which to study evolutionary processes because they are behaviourally and morphologically diverse. These mosquitoes are also inherently dependent of forests and so provide an ideal study organism in which to test the refuge hypothesis of historical climate change, which has been suggested as a pivotal force in species evolution. Before their evolutionary history can be determined, reliable identification of target species is required. In Chapter 3, we have developed a PCR mediated method to distinguish between isomorphic species of the Simpsoni Complex and use this method to provide inferences on ecology and species distributions; findings reveal an east-west difference in the distribution of the yellow fever vector Ae. bromeliae and non-vector Ae. lilii across the African continent, while these species meet in Uganda where they use the same larval habitats. In Chapters 4 and 5 we use a standard phylogeographic approach coupled with Approximate Bayesian Computation to uncover the evolutionary history of Aedes mosquitoes. Analysis reveals common phylogeographic signals within Aedes species which show populations have been subject to historical lineage diversification, admixture and recent demographic structure, in accordance with the refuge hypothesis of climate induced vicariance and secondary contact. Findings suggest that recent climate change throughout the late Pleistocene and early Holocene was important in generating African biodiversity. We find additional differences in the population structure of species between East and West Africa which could reflect more general biodiversity patterns within Africa. As the region connecting East and West African populations, Central Africa could be an important area regarding the diversification of species, including diseases and their vectors. We have identified a putative role for ecological speciation; for example in Chapter 4 we have provided additional evidence that worldwide populations of Ae. aegypti stem from a particularly successful source, indicating these mosquitoes possessed a trait integral for range expansion. In Chapters 4 and 5 we find that historical admixture within Africa characterises populations of Aedes mosquitoes and so may have played a key role in their evolutionary success. Since admixture can combine novel combinations of genetic material and raise adaptive potential, admixture may have been selectively advantageous for Aedes mosquitoes. Similarly, climate related secondary contact is likely to have been an important force for the evolution of other forest dependent species within Africa.

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Mic, Dumitrita Suzana. "Producing Collaborations Through Community-Level Processes of Climate Change and Water Management Planning." FIU Digital Commons, 2015. http://digitalcommons.fiu.edu/etd/2170.

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While much attention has been given to the ways local communities may be impacted by climate change, this dissertation focuses ethnographically on the local agencies decision-making processes, a less-studied aspect of this topic. The primary purpose of this dissertation research is to understand how government agencies in southern Florida integrate climate change into their decision-making processes while dealing with political resistance. This research expands our understanding on the cultural politics of a new kind of environmental change, where national and international climate-change politics is brought into local water politics to illuminate how new and not so new visions about life in the contemporary metropolis collide and collude. Using multiple research methods including ethnographic fieldwork, participant observation, semi-structured interviews, and document research, I analyze the activities of the Miami-Dade County Climate Change Advisory Task Force Committee (MDC-CCATF) as well as the water management practices of the regional water management agency, the South Florida Water Management District (SFWMD). My findings include the following: (1) the Task Force activities have spearheaded Miami’s institutional adaptation to climate change; (2) historic legacies have expanded and complicated decision-making processes at the District; (3) a focus on the certainties of climate-change science allows climate change to persist in politically contentious planning contexts. My dissertation concluded that while planning for potential climate-change impacts can be difficult due to multiple institutional constraints that resource agencies like the District have, scientists and policy-makers have crafted an innovative culture that is particularly visible at sites where science and decision making intersect.

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Barella, Ortiz Anais. "Analysis and modelling of soil moisture and evaporation processes, implications for climate change." Thesis, Paris 6, 2014. http://www.theses.fr/2014PA066115/document.

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Cette thèse étudie l'évaporation et l'humidité du sol, deux paramètres clefs du cycle hydrologique et du système climatique.L'évaporation potentielle (ETP) est un paramètre clef pour les modèles hydrologiques et agronomiques qui décrit les interactions entre la surface et l'atmosphère. Il constitue la base des estimations de l'évaporation réelle. Nous avons évalué, à l'échelle globale et pour le climat actuel ainsi que pour les changements attendus, des estimations de l'ETP basées sur des principes physiques ainsi que des approches empiriques. La méthode d'estimation du flux potentiel conseillée par la Food and Agriculture Organization (FAO) montre une sous évaluation par rapport au schéma de surface, ce qui a pu être relié à certaines hypothèses faites. Ceci implique aussi une sensibilité plus faible au changement climatique de la formulation proposée par la FAO. Nous avons aussi constaté que les méthodes empiriques ne représentent pas correctement l'impact du changement climatique sur l'ETP.L'humidité du sol est analysée du point de vue de la température de brillance en Bande-L (TB). Cette mesure du rayonnement émis par la surface dans une bande spectrale sensible à l'eau dans les premiers centimètres du sol, constitue une des pistes pour l'estimation de l'humidité de surface depuis l'espace. Des mesures de TB ont été comparées, au dessus de la Péninsule Ibérique, à des données simulées par deux schémas de surface. Un bon accord a été trouvé entre les observations et les simulations sur l'évolution temporelle des signaux. Par contre, les structures spatiales peuvent être très différentes au cours de l'automne et l'hiver à cause de cycles annuels très contrastés
This thesis deals with the study of evaporation and soil moisture, t wo main parameters of the hydrological cycle, and thus the climate system. First, potential evaporation (ET P ) is analysed. It is an important input to hydrological and agronomic models, key to describe the interactions between the surface e and the atmosphere, and the basis of most of the estimations of actual evapora tion. Physically-based and empirical methods to estimate ET P are evaluated, at a global scale, under current climate conditions and in a changing climate. The former methods correspond to those implemented in land surface models (LSM) and the Food and Agriculture Organization (F AO) reference evapotranspiration equation. The assumptions made in FAO's method underest imate ET P if compared to LSM methods. They also result in a lower sensitive ty of ET P to climate change. In addition, empirical equations are not able to reproduce the impact of climate change on ET P if compared to that from LSM methods. Soil moisture is the second aim of this thesis. It is treated t hrough the analysis of brightness temperatures (TB). These are a measure of the radiation emitted by the surface , and thus an optimum parameter to use in remote sensing techniques for soi l moisture retrieval. Measured TB from the Soil Moisture and Ocean Salinity (SMOS) mission are compared, over the Iberian Peninsula, to two sets of TB modelled estimates from two LSM. There is a good agreement in the temporal evolution between them. However, discrepancy es are found regarding the spatial structures, which become more evident during fall and winter and are mainly explained by differences in the annual cycle of measured and modelled TB

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Howell, Rachel Angharad. "Promoting lower-carbon lifestyles : the role of personal values, climate change communications and carbon allowances in processes of change." Thesis, University of Edinburgh, 2013. http://hdl.handle.net/1842/9509.

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Climate change is a pressing problem and substantial reductions in the greenhouse gas emissions that cause it are necessary to avert the worst impacts predicted. The UK has targeted an 80% reduction from 1990 emissions levels by 2050. This thesis investigates how to promote behavioural changes that will reduce emissions associated with individuals’ lifestyles, which comprise a significant proportion of the UK total. The thesis begins by appraising whether and how climate change communications, specifically films, can succeed in changing attitudes and behaviour. The impacts on viewers of the film The Age of Stupid were assessed using a fourstage panel survey. Increased concern, motivation to act, and sense of agency felt immediately after seeing the film did not persist, but respondents reported some behavioural changes. The longer-term follow-up suggests that behavioural intentions do not necessarily translate into action, but also revealed issues concerning the reliability of participants’ causal attributions of their behaviour. These and other challenges of conducting longitudinal studies of behavioural change related to climate change communications are discussed. The thesis then uses a model of behavioural change transposed from health psychology to analyse the processes of change employed or depicted by four climate change films, in order to identify more generally the strengths and limitations of films as means to promote mitigation action, and to demonstrate the potential utility of the model in the field of proenvironmental behaviour change. The issue is then considered from the opposite angle, with an examination of what has motivated individuals who have already adopted lower-carbon lifestyles. Qualitative research reveals that protecting ‘the environment’ per se is not the primary value stimulating most interviewees’ action; typically they were more concerned about the impacts of climate change on people in developing countries. Although analysis of a survey instrument showed that biospheric values are important to the participants, they tended to score altruistic values significantly higher. Thus it may not be necessary to promote biospheric values to encourage lower-carbon lifestyles. The final element of the work involved researching the opinions of members of Carbon Rationing Action Groups, seeking to understand what can be learned from their experiences of living with a carbon allowance, and the implications that the findings may have for potential government policies, especially personal carbon trading. The thesis concludes that, given the scale of action required, the difficulties individuals face when considering whether and how to adopt lower-carbon behaviours, and the limited impact of initiatives such as Carbon Rationing Action Groups and The Age of Stupid beyond a relatively small circle of people who tend to exhibit particular traits (such as a preference for frugality), significant UK emissions reductions will necessitate far-reaching legislation that will impact on everyday practices and behaviour.

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Jacob, Ruth E. "PROCESSES RELATED TO HYDRODYNAMIC AND MINERAL TRAPPING FOR THE PURPOSE OF CARBON STORAGE IN DEEP SALINE AQUIFERS." Case Western Reserve University School of Graduate Studies / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=case1450735566.

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Asdar, Sarah. "Climate change impact on ecosystems of Prince Edward Islands : role of oceanic mesoscale processes." Thesis, Brest, 2018. http://www.theses.fr/2018BRES0037/document.

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L’archipel du Prince Édouard est situé dans le Courant Circumpolaire Antarctique, entre le Front Subantarctique (SAF) et le front polaire (PF). Les positions de ces fronts se sont révélées très variables aux échelles interannuelles et mensuelles et ont montré une tendance à long terme à migrer vers le sud dans la région. L'activité tourbillonnaire, observée à la dorsale sud-ouest indienne, en amont de l’archipel, a également affiché une variabilité interannuelle et intra-annuelle ainsi qu’une tendance à la baisse sur ces 24 dernières années. A une échelle plus locale, nous avons souligné que les conditions aux îles sont impactées par ces tourbillons mésoéchelle produits en amont. La marée a également été mise en évidence comme jouant un rôle non négligeable dans la variabilité de la circulation entre les îles. Une configuration idéalisée a été mise en place pour la région afin d’étudier les propriétés des tourbillons et les mécanismes physiques à l’origine de leur formation. L'énergie potentielle tourbillonnaire disponible a révélé un maximum d'énergie aux alentours de 800 m de profondeur, confirmant le caractère « deep-reaching » des tourbillons. Cette activité tourbillonnaire a été montrée comme étant le résultat d'une combinaison d’instabilités barotropes et baroclines. Enfin, nous avons enquêté sur les conséquences potentielles d'une migration vers le sud du SAF dans la région des îles. Le modèle étant idéalisé, il nous a permis de simuler un déplacement vers le sud en déplaçant les conditions initiales ainsi que les conditions aux limites. Le principal résultat a été la nette diminution de l'activité mésoéchelle dans la région, ce qui pourrait avoir un impact sur les écosystèmes de l’archipel du Prince Édouard
The subantarctic Prince Edward Islands lie in the Antarctic Circumpolar Current, between the Subantarctic Front (SAF) and the Polar Front (PF). These fronts positions were found to be highly variable at interannual and monthly time scales and revealed a significant long-term southward trend in the region. The intense mesoscale activity, observed upstream the islands at the South West Indian Ridge, also showed an interannual and intra-annual variability as well a decrease in eddy kinetic energy over 24 years. At a more local scale, we highlighted that the archipelago’s environment was impacted by the mesoscale features produced upstream.Tides appeared to be another important driver of variability of the circulation in between the two islands.An idealised model configuration was designed for the Prince Edward Islands region to study the mesoscale eddy properties and the physical mechanisms of their formation at the ridge. The Eddy Available Potential Energy revealed a maximum of energy around 800 m depth, confirming the deep reaching characteristic of the eddy originated in the region and suggested the presence of a local energy source at this depth. This eddies activity was shown to be the result of a combination of barotropic and baroclinic instabilities occurring at the ridge.Finally, we investigated on the potential consequences of a southward shift of the SAF in the region of the islands.Because the model was idealised, it allowed us to simulate an SAF southward shift by shifting the initial and boundary conditions. The main result was the clear decrease of mesoscale activity in the region which could potentially impact the ecosystems of the Prince Edward Islands

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Centoni, Federico. "Global scale modelling of ozone deposition processes and interaction between surface ozone and climate change." Thesis, University of Edinburgh, 2017. http://hdl.handle.net/1842/25454.

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Atmospheric concentrations of surface ozone (O3) are strongly affected by deposition to the biosphere. Deposition processes are very sensitive to turbulence, temperature, relative humidity and soil moisture deficit and are expected to respond to global climate change, with implications for both air quality (e.g. human health) and ecosystem services (e.g. crop yields). In this PhD study, the global chemistry aerosol model UKCA (United Kingdom Chemistry Aerosol model) dry deposition scheme was thoroughly investigated. Some errors in the existing implementation of the current UKCA stomatal resistance and in-canopy aerodynamic resistance terms for O3 and NOw (NO2, PAN, PPAN, MPAN) were identified and corrected (WES scheme). These model corrections led to a decrease of the total annual dry deposition of -150 Tg(O3) yr-1 (-13%) which brings UKCA more in line with multi-model inter-comparison estimates. This was associated with a large increase of surface O3 concentration over land in the Northern Hemisphere (NH) with values up to 12 ppb (+50%) higher on annual average. Many studies have shown that O3 stomatal uptake by vegetation, which is the pathway leading to damage, accounts for 40-60% of total deposition on average. The remaining non-stomatal deposition flux is to external foliar surfaces, and soil. A more mechanistic non-stomatal dry deposition approach along with a scheme to simulate the effect of moisture on foliar surfaces on the stomatal transport (ZHG scheme) was introduced in UKCA to study the relative contributions of O3 flux occurring to stomatal and non-stomatal pathways at the global scale, and to explore the sensitivity of simulated surface O3 and O3 deposition flux. The ZHG scheme, led to significant changes in the O3 dry deposition velocity (Vd) (+40% in the North Hemisphere over boreal forests and -30% over tropical regions on annual average). The results of this study show that the ZHG scheme significantly changes the partitioning between stomatal and non-stomatal O3 flux. The non-stomatal fraction increased throughout the year and considerably during the cooler season and in spring (with maxima values by up to 60% for C3 grass and by up to 70% for needle leaf trees). The performance of both UKCA dry deposition schemes were compared with measurements, focussing on the diurnal and seasonal variations of the dry deposition velocity terms and the partitioning of O3 fluxes between stomatal and non-stomatal sinks. Overall, both UKCA dry deposition schemes capture the diurnal variations of Vd reasonably well. However, this study highlighted difficulties in comparing large grid (~280 x 390 km at mid-latitudes) averaged modelled values with site and vegetation specific characteristics of the measured exchange processes (~1 km2) and the driving meteorological variables. These differences in scale are a large source of uncertainty in the comparison of measured and modelled O3 Vd. Off-line simulation tests conducted on the non-stomatal deposition component with the ZHG scheme demonstrated the importance of modelling some key environmental and meteorological factors accurately (e.g. relative humidity, friction velocity, leaf area index). This was found to be crucial in order to improve O3 Vd model performance as well as improving the representation of specific vegetation properties. A comparison of the modelled global surface O3 concentration against observations both in the NH and SH revealed that the model performs well in the NH using both schemes, capturing the observed surface O3 cycle and the absolute values. The ZHG scheme led to a reduction of the annual bias (up to -13.5% on average) in the NH monitoring sites considered for this study. This is associated with a decrease in O3 deposition simulated with ZHG (as much as of -20% on annual average). By contrast, the seasonal cycle and absolute values of the observed surface O3 are not well reproduced by the model across the SH monitoring sites used in this study and a larger bias was found using the ZHG scheme (60% on average) compared to WES scheme (47% on average), as a consequence of an increase in O3 deposition (as much as of +20% on annual average) calculated with ZHG. A future climate integration for the 2090s using RCP 8.5 scenario was used to investigate the response of UKCA modelled O3 to climate change. The effect of climate change (by altering only the GHG concentrations predicted with RCP 8.5) on the dry deposition sink of O3 was addressed contrasting the two non-stomatal deposition parameterizations, and ignoring the changes in land-use and anthropogenic emissions. The study showed that O3 Vd over land declines from 2000 to 2100, and most strongly over vegetated areas (up to -24% over S. America, -17% over N. America and -10% over Europe). Climate change led to an increase of surface O3 concentration over land (by up to 20%). Whilst the two schemes behave similarly, and an increase in turbulence has been identified as the main driver, the decrease in land Vd is generally stronger in ZHG. This effect is more important over N. America and Eurasia where ZHG exhibits larger differences in deposition compared to WES as a result of changing climate. The increase in surface O3 over Arctic and Antarctic regions shows the effect that changes in O3 deposition might have on the long-range transport of O3. Finally, the influence of climate change on the partitioning of the O3 deposition flux was examined. This analysis revealed that more O3 is predicted to deposit through stomatal pathways with ZHG over N. America, C. Europe and E. Asia (up to +30%) compared to WES as a result of changing climate. Given that ZHG scheme captures the influence of meteorology and changing climate on surface O3 better than WES, it was concluded that modelled surface O3 using ZHG scheme showed a larger sensitivity to a changing climate than WES. These results imply potentially important effects of climate change on tropospheric O3, degrading air quality through the later decades of this century.

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Hank, Tobias Benedikt. "A Biophysically Based Coupled Model Approach For the Assessment of Canopy Processes Under Climate Change Conditions." Diss., lmu, 2008. http://nbn-resolving.de/urn:nbn:de:bvb:19-87254.

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Di, Bella Contreras José Manuel. "Climate change adaptation, business model innovation and socio-economic assemblages : a relational analysis of adaptive processes." Thesis, King's College London (University of London), 2018. https://kclpure.kcl.ac.uk/portal/en/theses/climate-change-adaptation-business-model-innovation-and-socioeconomic-assemblages(e8a5ad5a-600d-485a-bf69-e76f4ee171e6).html.

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The impacts of climate change will worsen existing problems of insecurity, poverty, inequality and environmental degradation. This multiplier effect requires strategic attention from all social actors. Current climate adaptation research focused on the role of the State and community- and individual-level adaptation, with limited analysis and empirical evidence available on adaptation by the private sector. This thesis addresses this research gap by analysing how medium and large firms respond to interruptions to business routines caused by climate-related impacts by studying the firm and different actors as economic assemblages where resources, innovation and relationships shape adaptation. The different forms of adaptive actions are forcing these assemblages of the firms themselves and their associates (including workers and host communities) to reconfigure their social and economic functions in distinct adaptation trajectories with different emergent properties. Informed by development theory, economic geography and emerging studies in climate adaptation, this thesis proposes a framework to understand individual firms’ adaptive measures framing their adaptive behaviour in relational processes. Climate change adaptation has a temporal dimension, one that requires to understand the past as a given location, to understand the sources of risk and vulnerability have accumulated through historical processes associated with a variety of social and economic factors, such as land tenure rights, uses of technology, governance processes, poverty and knowledge. It also has a temporal dimension that looks into the future, which requires foresight, flexibility and action to build capacities to cope with the impacts of extreme climate events and rapidly changing climate patterns of climate change. A characterisation of adaptive actions provided insights into some of these processes in early adopter firms business structures and mechanisms, which evidenced how firms mobilised resources, expertise, information and local innovation in response to climate stress, suggesting different implications of social well-being along supply chains. The thesis argues that established business configurations are failing to undertake adaptation without creating social trade-offs in these local assemblages, due to a failure to normalise socially oriented adaptive actions into their business model. There is currently an opportunity being missed to take advantage of the social nature of adaptation process to renegotiate more egalitarian relationships between firms and their associates and stakeholders that enhance social well-being and preserve developmental gains. Such negotiations will depend upon recognition of the interdependence between the multitude of actors experiencing climate stress to develop the capabilities necessary for equitable adaptation processes and outcomes under a changing planet. The technical and development approached to leverage the private sector capabilities to contribute to sustainable development, remain largely driven by models and practices that appeal to economic and capitalist views of social life. As climate change presses on social systems, new thresholds begin to be visualised, which present unique challenges for society. The thesis presents technical responses to climate stimuli which seek incremental adjustments to maintain present functions, but in doing so, these practices reveal the limit to adaptation and potential for forced transformation, where power and resources determine adaptation trajectories. A more just and desirable form of transformation is then considered, one based on a common language and co-production of new ideas and practices, which through cooperation and communication can allow for collective adaptation trajectories, beyond technocratic solutions to “the problem of climate change”, but as new spaces to challenge ideas of the private and public.

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Pasanen, Mortensen Marianne. "Anthropogenic impact on predator guilds and ecosystem processes : Apex predator extinctions, land use and climate change." Doctoral thesis, Stockholms universitet, Zoologiska institutionen, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-100720.

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Humans affect ecosystems by changing species compositions, landscape and climate. This thesis aims to increase our understanding of anthropogenic effects on mesopredator abundance due to changes in apex predator status, landscape and climate. I show that in Eurasia the abundance of a mesopredator, the red fox (Vulpes vulpes), is limited top-down by the Eurasian lynx (Lynx lynx) and bottom-up by winter severity. However, where lynx has been eradicated, fox abundance is instead related to bottom-factors such as cropland (paper I, II). Fox abundance was highest when croplands constituted 25% of the landscape (paper II). I also project red fox abundance in Sweden over the past 200 years and in future scenarios in relation to lynx density, land use and climate change. The projected fox abundance was highest in 1920, when lynx was eradicated and the proportion of cropland was 22%. In 2010, when lynx had recolonised, the projected fox abundance was lower than in 1920, but higher than in 1830. Future scenarios indicated that lynx abundance must increase in respond to climate change to keep fox at the same density as today. The results suggest a mesopredator release when lynx was eradicated, boosted by land use and climate change, and that changes in bottom-up factors can modify the relative strength of top-down factors (paper IV). From 1846-1922, lynx, wolverine (Gulo gulo) and grey wolf (Canis lupus) declined in Scandinavia due to persecution; however I show that the change in wolverine abundance was positively related to the changes in lynx and wolf abundance. This indicates that wolverine is subsidized by carrions from lynx and wolf kills rather than limited top-down by them (paper III). This thesis illustrates how mesopredator abundance is determined by a combination of top-down and bottom-up processes, and how anthropogenic impacts not only can change the structures of predator guilds, but also may modify top-down processes through changes in bottom-up factors.

At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Submitted. Paper 3: Submitted. Paper 4: Manuscript.

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Morgan, William Thomas. "Pollution aerosol across Northern Europe : assessing properties, processes and effects on regional climate." Thesis, University of Manchester, 2010. https://www.research.manchester.ac.uk/portal/en/theses/pollution-aerosol-across-northern-europe-assessing-properties-processes-and-effects-on-regional-climate(8c347b7e-baa9-4430-af93-911ad77eef7d).html.

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Atmospheric aerosols are the major component in the shorter-term variability governing the radiative balance of the climate system, particularly on regional scales. However, knowledge of the myriad of properties and processes associated with aerosols is often limited, which results in major uncertainties when assessing their climate effects. One such aspect is the chemical make-up of the atmospheric aerosol burden.Airborne measurements of aerosol properties across Northern Europe are presented here in order to facilitate constraint of the properties, processes and effects of aerosols in this highly populated and industrialised region. An Aerodyne Aerosol Mass Spectrometer (AMS) delivered highly time-resolved measurements of aerosol chemical components, which included organic matter, sulphate, nitrate and ammonium.The chemical composition of the aerosol burden was strongly determined by the dominant meteorological conditions in Northern Europe. Pollution loadings in North- Western Europe were strongly enhanced when air masses originated from Continental Europe. Conversely, much cleaner conditions were associated with air masses from the Atlantic Ocean.Organic matter was found to be ubiquitous across Northern Europe and predominantly secondary in nature, which is consistent with other analyses in polluted regions of the Northern Hemisphere. Furthermore, its concentration was generally comparable to, or exceeded that of, sulphate. Significant chemical processing of the organic aerosol component was observed. Highly oxidised secondary organic aerosol dominated, as the distance from source and photochemical processing increased.Ammonium nitrate was found to be a major component of the aerosol burden in Northern Europe, with peak contributions occurring in North-Western Europe, due to the co-location of its emission precursors (NH3 and NOx) in the region. Ammonium nitrate was found to be the dominant sub-micron chemical constituent during periods associated with enhanced pollution episodes. Its concentration was shown to be modulated by the thermodynamic structure of the lower troposphere, with enhanced concentrations prevalent at the top of the boundary layer. This phenomenon greatly enhanced the radiative impact of the aerosol burden; the increased mass and water uptake by the aerosol significantly amplified the aerosol optical depth in the region.The results presented in this thesis highlight a highly dynamic region, where major changes in emissions have played a significant role in determining the chemical composition of the aerosol burden. As substantial reductions in sulphur dioxide emissions have occurred over the past two decades in Northern Europe, the relative contribution of sulphate aerosols to the regional aerosol burden has decreased. Consequently, it is more pertinent to consider the roles of organic matter and ammonium nitrate, as their influence becomes more pronounced than sulphate on regional and global climate.

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Ackerfors, Linnea, and Amanda Hederén. "Climate Transition in Municipalities : Identifying ways to assess transition processes through indicators." Thesis, Linköpings universitet, Tema Miljöförändring, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-128107.

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Climate change has been recognised as one of the biggest challenges of our time. To prevent further climate change impacts, nations at COP21 further stressed the need to mitigate their greenhouse gas emissions enough to prevent dangerous temperature rise and to adapt societies to become more resilient. Municipals have been found important actors in this transition due to their power to inflict change on a local level. However, there is a lack of methods to assess how transition is made due to the fact that transition is a fairly new approach to managing climate change combined with a lack of completed transitions in municipalities. The purpose of this study is to explore the use of indicators as a method to assess municipal transition processes. Focusing on two Swedish municipalities that have been deemed vulnerable but at the same time apt to combat climate change, this study uses a triangulation of methods that are divided into two phases. The first phase uses a literature review in order to create a scientifically based list of transition indicators. The second phase uses document analyses and interviews in order to test the indicators and analyse transition process on a local level. The study revealed that there are multiple barriers and triggers for transition such as conflicting interests, economic factors, political steering, knowledge building- and awareness and long term perspectives, but that there also exist important tools for municipal transition in the form of networks through multi-level collaborations and plans/objectives. The findings in this study also suggests that the use of indicators as a method to assess transition could be viable, but that it is limited due to its contextual nature and lack of successful transitions to compare with.
Klimatförändringar har ansetts vara en av de viktigaste utmaningarna i vår tid. För att förhindra att vidare skador av klimatförändringarna kom nationer som deltog i COP21 överens om att minska sina växthusgaser tillräckligt mycket för att förhindra farliga temperaturförhöjningar och att anpassa sina samhällen till resilienta enheter. Kommuner anses vara viktiga aktörer i denna omställning då de har makt att påverka förändringar på en lokal nivå. Dock saknas metoder för att bedöma hur omställning utförs då omställning är ett nytt angreppssätt kombinerat med en brist på genomförda omställningar. Syftet med denna uppsats är att utforska användningen av indikatorer som metod för att bedöma omställningsprocesser. Genom att använda en triangulering av metoder som delats upp i två faser fokuserar studien på två svenska kommuner som har fastställts som känsliga inför klimatförändringarna men även att ha förmågan att hantera dem. Den första fasen består av en litteraturstudie som skapade en vetenskaplig grund som berörde en global och nationell nivå. Den andra fasen bestod av en dokumentsanalys och intervjuer för att utforska omställningsprocesser på en lokal nivå. Studien visar på att det finns flera barriärer och drivkrafter för omställning som konkurrerande intressen, ekonomiska faktorer, politisk styrning, kunskaps byggande- och medvetenhet och långsiktighet men även att det fanns verktyg som var viktiga för kommunal omställning som nätverk genom samarbeten på olika nivåer och planer/mål. Slutligen visar även studien på att användningen av indikatorer som metod för att bedömma omställning skulle kunna vara möjligt men att begränsningar finns då metoden dels är kontextberoende men även att det är svårt att göra jämförelser då ingen fullförd omställning har skett.

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Herrault, Joel. "Refuge from Climate Change? : The Principle of Non-Refoulement under the ICCPR and the ECHR in the Context of Climate Change." Thesis, Uppsala universitet, Juridiska institutionen, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-438698.

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In the early 1990s the Intergovernmental Panel on Climate Change predicted that the gravest effects of climate change could be on human migration, as millions would be displaced by coastal erosion, flooding, and drought. Today, this is considered a reality that is coming ever closer. Yet, there are currently no binding international frameworks dedicated to the issue of climate induced migration. In addition, the current regime of international refugee law is woefully inadequate at responding to the issue. Individuals that do not fall under the refugee definition are thus commonly left with the general scope of international human rights law standards, so-called complementary protection. On these premises, this thesis sets out to examine the circumstances under which the non-refoulement principle in international human rights law could be applied in the context of climate change effects and especially slow onset processes, and how the principle could potentially be developed. Principally through examining jurisprudence concerning the International Covenant on Civil and Political Rights and the European Convention on Human Rights, this thesis finds that while there is a possibility for non-refoulement obligations to arise due to the effects of climate change, the precise scope of such protection is unclear. Although case law has emerged and continues to do so, the complex nature of climate induced migration and the undeveloped jurisprudence on this issue leaves important questions unanswered. This thesis finds that there seems to be no obvious response to the question whether climate change is a relevant factor in the legal analysis of non-refoulement claims, and whether it should be. Furthermore, there are great challenges in discerning the required intensity of harm for the threshold to be met and protection to be granted. In addition, this thesis finds that applying the non-refoulement principle in the context of slow onset processes entails several difficulties, particularly concerning the timing and prediction of the harm. It is therefore concluded that, as long as there is no framework dedicated to the issue of climate induced migration, clarity will be much needed in case law as to the scope of non-refoulement obligations in the context of, especially, slow onset processes due to climate change.

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Lloyd, Andrea Heath 1967. "Patterns and Processes of Treeline Forest Response to Late Holocene Climate Change in the Sierra Nevada, California." Diss., The University of Arizona, 1996. http://hdl.handle.net/10150/565561.

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Steentjes, Katharine. "Speak up for change? : understanding the social costs and benefits of confronting environmental disregard." Thesis, University of Exeter, 2014. http://hdl.handle.net/10871/15678.

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In the face of stagnation in efforts to tackle the global increase of greenhouse gas emissions, there is a great need to broaden our understanding of normative processes that maintain and change social norms in relation to environmentally (un)sustainable lifestyles. My research aims to address this gap in the literature by examining the normative processes associated with climate change. More specifically I focused on identifying the interpersonal costs and wider benefits (in terms of social change) associated with the interpersonal confrontation of environmental disregard. Firstly, to establish a meaningful point of comparison for subsequent studies, I compared the normative status of environmental disregard and racial prejudice (Studies 1 & 2). I then moved on to examining perceptions and consequences of interpersonal confrontation of environmental disregard over the course of six studies by placing participants in the position of an observer of an interaction in which the confrontation occurred. The results consistently identified high social costs (reduced feelings of closeness and warmth) associated with confronting environmental disregard (but not racism). The costs of confronting environmental disregard were partly determined by the morality of the issue, the appropriateness of the confrontation, the pre-existing attitude of the observer and the justification used by the confronter for their reaction. My studies also tested different strategies to reduce the social costs for the confronter (such as invoking morality in different ways) and also assessed the consequences of confrontation for changes in perceptions of social norms, climate change attitudes and behavioural tendencies amongst those bearing witness. In relation to the consequences for behavioural tendencies resulting from interpersonal confrontation, the findings suggest that confrontation of environmental disregard encourages pro-environmental action tendencies if a scientific justification for the confrontation is provided. The final chapter of the thesis explores the theoretical and practical implications of these findings in relation to engendering processes of social change.

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Deus, Ernesto José Rodrigues Cardoso. "Distribution and natural establishment of Eucalyptus globulus in the Iberian Peninsula: insights into processes affecting plant establishment." Doctoral thesis, ISA, 2019. http://hdl.handle.net/10400.5/21193.

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Doutoramento em Engenharia Florestal e dos Recursos Naturais - Instituto Superior de Agronomia. Universidade de Lisboa
Eucalypt plantations expanded across many countries and became subject to controversy, particularly about their ecological impacts and invasive potential. The same is true in the Iberian Peninsula (Iberia) regarding Eucalyptus globulus Labill. This thesis is composed by six studies (chapters) tackling poorly explored aspects in these domains, with the following objectives: a) to evaluate potential future dynamics of E. globulus plantations in Iberia according to different climate change scenarios and possible conflicts with high biodiversity areas (Chapter 1); b) to explore the influence of different factors on the natural establishment of E. globulus (Chapters 2-5); c) to perform a review of the literature investigating the natural establishment of eucalypt species (Chapter 6). In Iberia, under both climatic scenarios, the suitable range of E. globulus plantations is expected to shrink and conflicts with high biodiversity areas may aggravate (Chapter 1). A countrywide survey in Portugal to estimate E. globulus recruitment, using Google Street View, showed that recruitment is mostly influenced by climatic variables (annual precipitation and thermal amplitude) and that Google Street View is a cost-efficient alternative to car surveys (Chapter 2). Field surveys in E. globulus plantations in Central Portugal showed abundant recruitment along plantation edges, influenced by local factors such as soil cover and tree age. Wildlings, mostly adult, are spread up to 76 meters from plantations (Chapter 3). A sowing experiment using E. globulus seeds showed that germination and survival was enhanced after harrowing (Chapter 4). A seed predation experiment revealed that E. globulus seeds are highly attractive but they have escaped in many locations (Chapter 5). The literature review retrieved 37 studies, addressing 61 eucalypt species in seven countries. Key factors influencing eucalypt recruitment include fire, propagule pressure and disturbances (Chapter 6)
N/A

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Ndebele, Nontokozo. "South African asset manager perceptions on the integration of climate change risks into equity investment decision-making processes." Master's thesis, University of Cape Town, 2015. http://hdl.handle.net/11427/20120.

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The growing interest responsible investing strategies driven by bodies such as the United Nations Principles for Responsible Investing Initiative has resulted in issues such as climate change and its impact on investment portfolios becoming part of the asset management industry discourse. However, the degree to which these issues are perceived by asset managers to be significant has not been expanded upon extensively in literature. This study was undertaken to evaluate South African asset manager perceptions regarding the integration of climate change risks within equity investment decision-making processes. The study was further aimed at providing an understanding of preferred methods of climate change risk integration, where integration does take place, and the perceived barriers to integration within the South African Asset Management industry. To achieve the above-mentioned aims, an online survey of South African asset managers was conducted. The questions in the survey comprised a combination of open ended and closed ended questions with Likert and ranking scales being used. The data which was both quantitative and qualitative in nature was analysed using descriptive statistics and thematic analysis methods involving the identification of trends.

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Quiroga, Allison. "Carbon Flux and Weathering Processes in Icelandic Glacial-Fed Rivers." TopSCHOLAR®, 2018. https://digitalcommons.wku.edu/theses/2568.

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An investigation into the carbon dynamics and weathering processes occurring in Icelandic glacial-fed streams was conducted during the spring to summer seasonal transition in June of 2017. Four major outlet rives were sampled from the glaciers of Gígjökull, Steinsholtsjökull, Sólheimajökull, and Falljökull. Markarfljót, the major river that Gígjökull, Steinsholtsjökull, and many other glaciers drain into, was also sampled. Longitudinal sampling occurred at all sites to capture downstream trends in the hydrogeochemistry and carbon dynamics. Distinct differences in geochemistry between glacier surface meltwater, sub-glacial waters, pro-glacial lake water, and post-mixed downstream samples were evident in the data. Glacier surface streams were characterized by relatively colder water temperatures, lower specific conductivity, lower total dissolved solids (TDS) and ion concentrations, and more enriched δ13CDIC values than downstream samples. The THINCARB model was used to calculate the total dissolved inorganic carbon (TDIC), excess partial pressure of carbon dioxide (EpCO2), and percent contribution to TDIC by bicarbonate (HCO3), carbonate (CO3), and carbonic acid and dissolved CO2 (H2CO3). All sites showed a slight decreasing trend in DIC and EpCO2 downstream. The calculated CO2 flux ranged from 1.14 × 107 g/yr to 2.80 × 109 g/yr. The DIC flux ranged from 6.81 × 107 g/yr to 8.44 × 109 g/yr. The average carbon within the CO2 fluxing in these rivers accounts for 0.0004% of the annual, global flux of carbon. The δ13C values were the most variable throughout the study and indicate there are multiple sources influencing the river downstream. This study suggests that, despite previous assumptions and estimations, these glacial-fed rivers act as sources of CO2; however, the samples from this study only provide a snapshot into the carbon flux dynamics during the Spring to Summer seasonal transition. In most samples, HCO3 was the dominant species contributing to DIC content within the rivers, suggesting that DIC is being transported to the ocean as HCO3 but sourced to the atmosphere as CO2. By acting as sources of CO2 to the atmosphere, the process of glaciers melting, which drive geochemical processes within the rivers, are contributing to a positive feedback loop with respect to global warming.

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Ajao, Saidat Aderonke. "Decision-making processes of African leaders on climate change : a case study of the succession to the Kyoto-Protocol." Thesis, Durham University, 2013. http://etheses.dur.ac.uk/7358/.

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The research examines the decision-making processes of African Leaders in the context of a common international issue. The Theory of Bounded Rationality is utilised as theoretical framework. More specifically, the research explores how a group of African Leaders come together to make a common decision known as the Common African Position in relation to the succession to the Kyoto Protocol under the United Nations Framework Convention on Climate Change (UNFCCC). The originality of the research is contributed by decision-making processes utilising the Bounded Rationality Theory in the context of climate change. This is taken further by utilising the model in the decision-making processes of African Leaders as limited research has been conducted in this field in Africa. Researchers have argued that whilst extensive research has been undertaken in the US and UK, only a limited amount has been conducted in other regions (Elbanna and Child 2007). Furthermore, Hoskisson, et. al.,. (2000) argues that research on strategy practice in emerging economies such as China, and Latin America has not been matched with other regions such as, Africa and the Middle East. The originality of the research is also presented by the uniqueness of the case study. The study was conducted during the largest ever political gathering of world leaders – The Fifteen Session of the Conference of the Parties and the Fifth Session of the Meeting of the Parties of the UNFCCC (COP15) in Copenhagen, Denmark in December 2009. COP15 comprised 120 Heads of States and Governments and 193 national delegations including Member States of the continent of Africa. The research design was qualitative in nature. The methods for the primary data collection were Semi-structured Interviews, Focus Groups and Participant-Observation. Participants were Heads of Government, Ministers and other leaders, i.e. Secretary Generals, Ambassadors and Directors. Secondary data in the form of books, speeches, articles, newspapers, briefs and other publications were also utilised. The data was analysed using content analysis. The analyses revealed that the decision-making processes commenced two years before COP15. The decision-making processes were definitive, co-ordinated and structured involving a wide number of strategic organisations to the continent of Africa, i.e. the African Union Commission (AUC). The decision-making processes were largely followed by the group of African Leaders prior to and during the initial week of COP15. However, during the High-level Segment the dis-unity amongst African Member States became apparent. Bi-lateral deals with developed nations outside the African Common Position were at play, especially by South Africa and Ethiopia. The final outcome of COP15, the ‘Copenhagen Accord’ further revealed the decision-making processes and decisions made by African Leaders were irrational. Individual country interests were paramount, resulting in a total failure by the African Group to maintain the Common African Position. The findings also revealed that due to the diverse nature of the impact of climate change on different African regions, the implications of a common decision in addressing climate change in the future should be circumvented. Limitations of the study include the high security level during COP15 due to the attendance of world leaders, the immense size of the event in terms of participants, and the large number of meetings, which made it impossible for the researcher to follow all activities that were pertinent to decision-making. The research makes contributions to academia and to practice. Academically, in the field of strategic decision-making and by the use of Bounded Rationality; and the application of the Theory of Bounded Rationality in the context of the decision-making processes of African Leaders is novel in the literature further contributed by the extraordinary United Nations COP15 Conference. Furthermore, the results support the assumptions of Bounded Rationality in decision-making. In the field of practice, it suggests ways in which the decision-making processes of African Leaders in an international setting can be improved as it relates to climate change. The research concludes with recommendations, areas for further research in the field of strategic decision-making and a reflection of the research journey.

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Sarpong, Eunice Adwoa. "Gender and Climate Change Adaptation Strategies in Agriculture: Lessons from Farming Communities in Ejisu Municipality, Ghana." Thesis, Örebro universitet, Institutionen för humaniora, utbildnings- och samhällsvetenskap, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-93720.

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Climate change poses a threat to agriculture. Ghana’s agriculture is mainly dependent on rainfall, this makes subsistence farmers majority of whom are women more vulnerable to the impacts of climate change. That said, the impacts of climate change are felt differently by men and women due to their social assigned roles and responsibilities. This study examined the dimensions along which gender matters in adaptation strategies.The study used a case study approach, the Ejisu municipality in Ghana was selected for the study. To understand the gender narratives and how this affects adaptation strategies 10 farmers, and 2 agriculture extension officers were sampled. An inductive approach was used to analyze the core themes that emerged from the data.The findings of the study show that smallholder farmers in Ejisu municipality are changing their agricultural practices due to the changes in climatic conditions. Female farmers were seen to be less adaptive due to gender norms and challenges with access to productive resources. The common adaptative measures used by both male and female farmers are crop rotation, mixed farming, use of agrochemicals, organic fertilizers, leaving land fallow, delayed planting, and conservative agriculture.The study findings further show there are complexities in gender dimensions in the agricultural process and this affects adaptation strategies. The study recommends raising public awareness on climate change by providing adequate support to train farmers on sustainable adaptation, strengthening institutional capacity to ensure gender-responsive initiatives in agriculture, and create equitable access to resources to enhance adaptive capacities.

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Marshall, Jill. "Lithologic, Climatic, and Biotic vs. Abiotic Controls on Erosion and Landscape Evolution." Thesis, University of Oregon, 2015. http://hdl.handle.net/1794/19291.

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The triumvirate of tectonics, lithology, and climate control landscape evolution. This study quantifies how lithologic variation and climate-mediated changes in ecosystems perturb steady state processes in the unglaciated, soil-mantled Oregon Coast Range (OCR). I first demonstrate that minor grain-scale differences in rock properties in a seemingly uniform sandstone control differences in rock strength, biotic bedrock-to-soil production efficacy, and erosion rates and influence relief at the watershed scale. I then build on sedimentology, paleoecology, and isotopic-derived paleoerosion data I collected from a new 50 ka sediment archive at Little Lake, OR to explore climate controls on soil production and erosion rates 21 ka across the OCR and spanning 50 ky within a single watershed. In Chapter III, I combine a mechanistic frost weathering model with a regional Last Glacial Maximum (LGM) climate reconstruction and paleovegetation data to demonstrate that accelerated frost-driven erosion was pervasive across the OCR during the LGM. My findings provide a new framework to quantify how the late Pleistocene affects modern erosion and soil formation rates in unglaciated environments and implies that most landscapes reside in a transient state. In Chapter IV, I document climate-mediated ecosystem influence on erosion rates over 3 climatic intervals. 10Be-derived erosion rates increase 3x (from 0.6 mm/yr to 0.21 mm/yr) as the OCR transitioned from the open forest-dominated marine isotope stage (MIS) climate interval (50-26 ka) into the periglacial subalpine MIS 2 glacial interval (26-13 ka). Measured erosion rates fell by more than half as the subalpine ecosystem gave way to the modern MIS 1 closed canopy Douglas-fir forest. Coupling paleovegetation-derived climate information with core observations I model frost weathering intensity from ~ 43 ka to 21 ka and establish a correspondence with increasing frost weathering intensity and increasing 10Be-derived erosion rates. Utilizing a transient mixing depth and erosion rate model, I am able to broadly replicate measured erosion rates at Little Lake through time. My findings contradict previous work that suggests climate has only weak control on erosion rates. This dissertation includes previously published and unpublished co-authored material.

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Turner, Jennifer 1979. "Investigating the effects of climate change and sea level rise on the coastal processes of the Beaufort Sea, Yukon Territory." Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=81448.

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High latitude areas have been identified in most GCMs as regions where global warming will appear earliest and be the greatest. Since much of Canada's north is underlain by permafrost, a warming of 3-5°C could cause widespread erosion and thermokarst. The Arctic coastal zone is particularly vulnerable, as it lies at the interface between terrestrial systems dominated by permafrost, and marine systems dominated by sea ice and wave action. This study aims at understanding some mechanisms of arctic coastal erosion, such as thermoerosional niches and block failure. The final goal of this research is to identify the areas of Herschel Island, Yukon Territory, which are likely to experience the greatest magnitude of change in the near future. This information is then coupled with a climate change scenario in order to predict future coastal erosion in the area.

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Haider, Syed Kumail. "Oxygen carrier and reactor development for chemical looping processes and enhanced CO2 recovery." Thesis, Cranfield University, 2016. http://dspace.lib.cranfield.ac.uk/handle/1826/10014.

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This thesis’s main focus is a CO2 capture technology known as chemical looping combustion (CLC). The technology is a novel form of combustion and fuel processing that can be applied to gas, solid and liquid fuels. By using two interconnected fluidised-bed reactors, with a bed material capable of transferring oxygen from air to the fuel, a stream of almost pure CO2 can be produced. This stream is undiluted with nitrogen and is produced without any direct process efficiency loss from the overall combustion process. The heart of the process is the oxygen carrier bed material, which transfers oxygen from an air to fuel reactor for the conversion of the fuel. Oxygen carrier materials and their production should be of low relative cost for use in large-scale systems. The first part of this research centres on development and investigative studies conducted to assess the use of low-cost materials as oxygen carriers and as supports. Mixed-oxide oxygen carriers of modified manganese ore and iron ore were produced by impregnation. While copper (II) oxide supported on alumina cement and CaO have been produced by pelletisation. These oxygen carriers were investigated for their ability to convert gaseous fuels in a lab-scale fluidised bed, and characterised for their mechanical and chemical suitability in the CLC process. The modified ores and pelletised copper-based oxygen carriers’ mechanical properties were enhanced by their production methods and in the case of the modified iron ore, significant oxygen uncoupling was observed. The copper-based oxygen carriers particularly those containing alumina cement showed high conversion rates of gaseous fuels and improved mechanical stability. The second part of this research thesis focuses on the design philosophy, commissioning and operation of a dual-fast bed chemical looping pilot reactor. Based on the operational experience, recommendations for modifications to the CLC system are discussed. In support, a parallel hydrodynamic investigation has been conducted to validate control and operational strategies for the newlydesigned reactor system. It was determined that the two fast bed risers share similar density and pressure profiles. Stable global circulation rate is flexible and could be maintained despite being pneumatically controlled. Reactor-reactor leakage via the loop-seals is sensitive to loop seal bed-height, and inlet fluid velocity but can be maintained as such to ensure no leakage is encountered.

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Shi, Jie. "Integrated modelling of hydrological and hydrodynamic processes, dynamic bacteria decay with climate change and intensive farming in riverine and estuarine water." Thesis, Cardiff University, 2016. http://orca.cf.ac.uk/98617/.

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The water quality deteriorations in river and estuarine waters are a global issue. Particularly, the water quality impairment due to contamination of Faecal Bacteria Indicator, such as E. coli and Faecal Coliform in river channel, estuary bathing and shellfish waters are of special interests due to potential risks to human health. These indicators are important in water quality assessment outlined in both EU Water Framework Directive and US Clear Water Act. The hypothesis of the study is that the global climate change and intensive farming would cause severe deterioration to faecal coliform levels in these water bodies. Approaches to quantify these impacts are carried out with numerically modelling through catchment model Soil and Water Assessment Tool (SWAT) and hydrodynamic model DIVAST with the focus in the coastal catchment of river Frome and Piddle connected to a natural harbour in Dorset, southern England.

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Cusack, Michael. "Physical and chemical processes affecting atmospheric aerosols in the Western Mediterranean regional background." Doctoral thesis, Universitat Autònoma de Barcelona, 2013. http://hdl.handle.net/10803/129553.

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En este trabajo se muestra un estudio detallado de las fuentes de emisión y de los procesos físico-químicos que afectan a los aerosoles atmosféricos en el entorno regional de Montseny, situado en el Mediterráneo Occidental, una región relativamente poco estudiada en cuanto a calidad del aire. En el marco de calidad del aire, el estudio de los aerosoles atmosféricos está siendo de gran y creciente interés en la actualidad debido tanto a los potenciales efectos perjudiciales en la salud derivados de la exposición a estos contaminantes, como a sus efectos en el clima. Se ha llevado a cabo el análisis de una extensa serie temporal (2002-2010) de niveles de PM2.5 (material particulado de diámetro menor de 2.5 µm) y de su composición química, con el objetivo de describir las tendencias y fluctuaciones en las concentraciones, así como de identificar las posibles causas de estas variaciones. El análisis de la tendencia temporal de PM2.5 mostró una disminución estadísticamente significativa, generalizada a lo largo de Europa. Esta tendencia de disminución se atribuye a la eficacia de estrategias de reducción de la contaminación aplicadas por los países miembros de la UE, dado que muchos de los compuestos asociados a actividades antropogénicos, como el sulfato, el carbono orgánico y muchos metales traza, muestran un descenso gradual. Por otro lado, también se demostró que parámetros meteorológicos a escala global, como la Oscilación del Atlántico Norte (NAO), pueden regir las tendencias en las concentraciones de PM a través de Europa. En ciertos países, la recesión económica de los últimos años también parece haber afectado a los niveles de contaminantes antropogénicos. Este trabajo incluye la identificación y caracterización de las variaciones diarias y estacionales, así como de las fuentes de emisión, de PM1 (material particulado de diámetro menor de 1 µm) y de partículas sub-micrónicas. Las principales fuentes de emisión incluyen sulfato secundario, aerosol orgánico secundario, combustión de fuel oil, trafico rodado, quema de biomasa, emisiones industriales y nitrato. La formación de nuevas partículas y su posterior crecimiento se identificó como una fuente importante de partículas ultrafinas (partículas menores de 100 nm de diámetro). Durantes lo meses más cálidos las concentraciones de partículas muestran un aumento debido a que los procesos fotoquímicos de formación de partículas se ven favorecidos, las concentraciones de materia mineral son también más elevadas, hecho asociado a procesos de resuspensión del suelo y a intrusiones Saharianas mas frecuentes, se registran niveles más altos de sulfato y de compuestos procedentes del tráfico marítimo como consecuencia de brisas marinas más pronunciadas, y las condiciones son más propicias para la generación de emisiones biogénicas.. Por otro lado, durante los meses más fríos se describen episodios de contaminación intensos a consecuencia de condiciones anticiclónicas que causan el estancamiento de las masas de aire y la acumulación de contaminantes atmosféricos a través de la región. Estos episodios se caracterizan especialmente por niveles elevados de nitrato. La meteorología local, y específicamente la acción de brisas de mar y montaña, se identifican como un agente que controla el transporte de masas de aire contaminadas desde zonas urbanas a zonas rurales, y que rige la variabilidad diaria de aerosoles atmosféricos. Durante los meses fríos, la formación de nuevas partículas se observa en ausencia de una atmósfera contaminada, siempre que exista suficiente radiación solar y los gases precursores necesarios (acido sulfúrico, vapores orgánicos semi-volátiles). Durante los meses cálidos, la formación de nuevas partículas se observa con mucha más frecuencia debido a una radiación solar más intensa y a concentraciones más elevadas de gases precursores procedentes de emisiones biogénicas, dándose incluso en atmósferas contaminadas. Además, en este trabajo se describe la posibilidad de evaporación de partículas, que parece verse favorecida bajo condiciones de altas temperaturas, intensa radiación solar, baja humedad relativa y de dilución atmosférica.
A detailed study of the physical and chemical processes and sources affecting atmospheric aerosols in Montseny in the Western Mediterranean regional background is presented in this work, a region relatively understudied in Europe in this field. Atmospheric aerosols in the context of air pollution is currently an area of study of great interest owing to the health implications of exposure to airborne contaminants and the effects of aerosols on global climate change. A long-term time series of data (2002-2010) of PM2.5 (particulate matter of diameter less than 2.5 µm) and chemical composition is analysed with the aim to identify the trends and fluctuations in concentrations, and the possible causes for such fluctuations are described. Trend analysis of PM2.5 shows a decreasing trend with statistical significance for levels of PM across Europe. This decreasing trend is attributed to the efficacy of pollution abatement strategies, as many components associated with anthropogenic activities undergo a gradual decrease such as sulphate, organic carbon and trace metals. Furthermore, large scale meteorology such as the North Atlantic Oscillation is also identified as an influencing process affecting PM concentrations across Europe. In certain countries the economic recession of recent years has appeared to further compound these decreasing trends in ambient pollutant levels. The emission sources of both PM1 (particulate matter of diameter less than 1 µm) and sub-micrometre particles are identified and the daily and seasonal variations in the emission sources are described. These sources include secondary sulphate, secondary organic aerosol, fuel oil combustion, traffic and biomass burning, industrial and nitrate. New particle formation and growth is identified as an important source of ultrafine particles (particles of diameter less than 100 nm). Many of these sources undergo a distinct daily and weekly variation and seasonal variation associated with anthropogenic activities and meteorology across the region, with elevated concentrations during the warmer months as a result of enhanced photochemistry, elevated concentrations of crustal material associated with soil resuspension and increased Saharan dust intrusions, elevated levels of sulphate and shipping emissions as a result of pronounced sea breezes, and enhanced biogenic emissions. Intense episodes of pollution are described during the colder months as a result of anticyclonic conditions causing air mass stagnation and the accumulation of pollutants across the region. These episodes are especially characterised by elevated concentrations of nitrate. Local meteorology, specifically the action of mountain and sea breezes, are identified as controlling agents for the transport of polluted air masses from urbanised areas to rural areas, and govern the daily variability of atmospheric aerosols. During the colder months, new particle formation is observed to occur in the absence of a polluted atmosphere, provided solar radiation and the necessary gaseous precursors (sulphuric acid, semi-volatile organic vapours) are available. However, during warmer months, new particle formation is observed to be much more frequent owing to the intensified solar radiation and increased concentrations of gaseous precursors from biogenic emissions, even in polluted atmospheres. This scenario has not been described in many publications for non-urban environments. Furthermore, the possibility of particle evaporation is described, suggesting that gas-to-particle transformations (homogenous nucleation) are reversible, and this process is significantly underreported in literature. Evaporation appears to be favoured under warm temperatures, high solar radiation, low relative humidity and atmospheric dilution.

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Setegn, Shimelis Gebriye. "Modelling Hydrological and Hydrodynamic Processes in Lake Tana Basin, Ethiopia." Doctoral thesis, KTH, Vattendragsteknik, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-12024.

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Lake Tana Basin is of significant importance to Ethiopia concerning water resources aspects and the ecological balance of the area. The growing high demands in utilizing the high potentials of water resource of the Lake to its maximal limit, pictures a disturbing future for the Lake. The objective of this study was to assess the influence of topography, soil, land use and climatic varia-bility on the hydrological and hydrodynamic processes of the Lake Tana Basin. The physically based SWAT model was successfully calibrated and validated for flow and sediment yield. Se-quential uncertainty fitting (SUFI-2), parameter solution (ParaSol) and generalized likelihood un-certainty estimation (GLUE) calibration and uncertainty analysis methods were compared and used for the set-up of the SWAT model. There is a good agreement between the measured and simulated flows and sediment yields. SWAT and GIS based decision support system that uses multi-criteria evaluation (MCE) was used to identify the most vulnerable areas to soil erosion in the basin. The results indicated that 12 to 30.5% of the watershed is high erosion potential. Pro-jected changes in precipitation and temperature in the basin for two seasons were analyzed using outputs from fifteen global climate models (GCMs). A historical-modification procedure was used to downscale large scale outputs from GCM models to watershed-scale climate data. The results showed significant changes in streamflow and other hydrological parameters in the period between 2045-2100. SWAT was combined with a three dimensional hydrodynamic model, GEMSS to investigate the flow structure, stratification, the flushing time, lake water balance and finally the Lake‘s water level response to planned water removal. We have found an alarming and dramatic fall of the water levels in Lake Tana as response to the planned water withdrawal. The combination of the two models can be used as a decision support tools to better understand and manage land and water resources in watersheds and waterbodies. The study showed that the Lake Tana Basin may experience a negative change in water balance in the forthcoming decades due to climate change as well as over abstraction of water resources.
QC 20100720

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Gilbert, Genevieve. "Adaptive capacity, adaptation strategies and migration in the Canadian Prairies during the Dirty Thirties: Lessons for drought-migration processes under future climate change." Thesis, University of Ottawa (Canada), 2009. http://hdl.handle.net/10393/28162.

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This research examines the emergence of migration as a household adaptation strategy to drought in Alberta in the 1930s. Existing research on human migration in response to natural hazards tends to be limited in terms of empirical examples, particularly migration in response to climate stresses. The purpose of this study is to examine the detailed factors that influenced adaptive capacity and adaptation strategies of residents in south-eastern Alberta during the 1930s and to examine migration as one form of adaptation to drought. Data collection involved 37 in-depth semi-structured interviews in south-eastern Alberta and north-western Alberta, a literature review and archival data analysis. This study can help inform our understanding of future household vulnerability to drought in rural Alberta and migration as a potential adaptation strategy to climate change.

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Berauer, Bernd Josef [Verfasser], and Anke [Akademischer Betreuer] Jentsch. "Processes altering species richness, primary production and leaf nutritive quality across European grasslands exposed to climate change / Bernd Josef Berauer ; Betreuer: Anke Jentsch." Bayreuth : Universität Bayreuth, 2021. http://nbn-resolving.de/urn:nbn:de:bvb:703-epub-5781-3.

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Nettley, Amy Jessica. "Visualising change in the Tamar Valley : participatory processes for generating 3D visual tools to communicate sea-level rise." Thesis, University of Exeter, 2013. http://hdl.handle.net/10871/15030.

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This thesis introduces and analyses a unique approach which involved iteratively engaging with stakeholders to generate a film about sea-level rise at a heritage site. The project used fine-scale remote sensing techniques, including airborne and terrestrial laser scanning (TLS), to produce spatially accurate and realistic 3D digital visualisations of projected sea level rise at Cotehele Quay, a site on the River Tamar in Cornwall which is owned and managed by the National Trust. Area residents and stakeholders were involved in a series of focus groups which provided guidance on the integration of the spatial models into a short film. This thesis makes an original contribution to knowledge about how non-scientific audiences understand and interpret visual realism and spatial accuracy when engaged with the process of developing such a tool. Ultimately, the thesis proposes a new kind of visual realism based on this knowledge, known as ‘participatory realism’. The main output of this research was a film, ‘Changing Tides at Cotehele Quay’, which is presently being used by the National Trust as part of their wider communication toolkit. In addition to reflecting on the production of the film, the thesis makes the argument that at present TLS is not being proactively used to engage wider audiences. The research explored how TLS and other spatial data can be used in settings which are more public-facing; the thesis analyses the results of this innovative practice and interrogates the way in which people interacted and responded in the course of their participation.

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Wasserfall, Michiel Nicolaas. "Rain events based hillslope hydrological processes at the Langgewens Experimental Farm, Western Cape, South Africa." Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/80045.

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Thesis (MScAgric)--Stellenbosch University, 2013.
ENGLISH ABSTRACT: Hillslope hydrology represents a complex system with several interacting processes influencing the movement of water through the landscape. The Western Cape area of South Africa is expected to be impacted on by a change in climate and the importance of water management that will increase in the future. Climate, especially precipitation, is the driving factor behind the hydrological system and there are currently no predictions as to what the impact will be on the hydrological conditions. The main objective of the study is to understand the hydrological responses along a hillslope and secondly to determine the effect of climate change on the hydrology by using hydrological models. The studied system is situated on the Langgewens Experimental Farm, north of Malmesbury in the Swartland region of the Western Cape. Six sites in a range of vegetation, land use and expected soil types along a toposequence were investigated. All sites are rain fed areas with natural vegetation, seasonal or long-term shrubs. Through monitoring different components of the hydrological cycle, including rainfall, overland flow, infiltration, soil water content, base flow and water table depth at the different sites, the movement of water through the landscape can be defined. Hillslope hydrological processes at different positions on the hillslope were investigated. The baseline data obtained during this process was used in hydrological modelling for the different positions on the hillslope to determine the accuracy of model predictions. Expected future climatic conditions were emulated in this model to determine the possible effect of a change in climate on the hydrological system. The research confirmed the complex interaction between different processes within the hydrological system. At each point along the toposequence different components of the hydrological cycle contributed on a different scale to the hydrological system. Soil properties were the most significant factor influencing water movement through the landscape, directly impacting infiltration, overland flow, lateral water flow and deep percolation. This resulted in water table fluctuations through the seasons as the contribution of different components towards the hydrological cycle changed. By comparing soil water content measurements through the season with modelled water content levels, accurate hydrological models were created for different measuring points in the landscape. By using forecasted climate data of two different weather generators, accurate estimations of expected soil water content were possible. This indicated that droughts will occur on a regular basis in the future. This research made it possible to understand water movement through the landscape at hillslope level and contributed towards future water management plans by estimating future soil water content levels based on current predictions.
AFRIKAANSE OPSOMMING: Heuwelhang hidrologie omskryf die proses van water beweging deur die landskap en dit word deur verskeie prosesse beinvloed. Onder huidige toestande word verwag dat die Weskaap provinsie van Suid-Afrika warmer en droëer sal word in die toekoms as gevolg van klimaatsverandering. Dit sal die noodsaaklikheid van effektiewe waterbestuur verhoog in die toekoms. Klimaat, en in besonder reënval, is die dryfkrag agter die hidrologiese sisteem en huidiglik is daar geen aanduiding van wat die effek van klimaatsverandering op die hidrologiese sisteem gaan wees nie. Die eerste doel van die studie is om die heuwelhang se hidrologiese sisteem te ontleed en tweedens om die impak van klimaatsverandering op die hidrologiese sisteem te bepaal deur gebruik te maak van hidrologiese modelle. Die studie area is geleë op die Langgewens Proefplaas, noord van Malmesbury in die Swartland distrik van die Weskaap. Ses verskillende posisies is op die heuwelhang geselekteer op grond van posisie in die landskap, plantegroei, landgebruik en verwagte grondvorms. Al die studiepunte ontvang slegs water deur reën en die landgebruik wissel ten opsigte van natuurlike plantegroei, en eenjarige- of meerjarige gewasse wat gevestig is. Deur verskillende komponente van die hidrologiese sisteem te monitor, insluitend reënval, oppervlak afloop, infiltrasie, grond water inhoud, laterale water vloei en die diepte van die watertafel, kan die beweging van water deur die landskap gedefinieër word. Die data wat versamel is gedurende die proses word gebruik om die akkuraatheid van die hidrologiese modelle se resultate te bepaal. Tesame met vooruitgeskatte klimaatdata kan die modelle gebruik word om die impak van klimaatsverandering op grondwater toestande vas te stel. Die navorsing toon die komplekse interaksie tussen verskillende prosesse in die hidrologiese sisteem. By elke punt in die landskap dra verskillende komponente op verskillende skale by tot die hidrologiese sisteem. Grondeienskappe het die meeste invloed op die verskillende komponente van die hidrologiese sisteem en beïnvloed die infiltrasie, oppervlak afloop, laterale water vloei en diep dreinering. Soos die verskillende komponente se bydrae tot die hidrologiese sisteem verander, vind daar fluktuasies in die diepte van die water tafel plaas. Deur die vergelyking van gemete grondwaterinhoud teen hidrologiese model voorspelde grondwaterinhoude, is akkurate hidrologiese modelle opgestel vir verskillende punte in die landskap. Deur gebruik te maak van twee moontlike verwagte klimaat toestande, is gevind dat droogtes op ‘n roetine basis in die toekoms sal voorkom. Die navorsing maak dit moontlik om die beweging van water deur die landskap te verstaan en dra by tot die opstelling van toekomstige waterbestuur planne. Dit word moontlik gemaak deur die vooruitskatting van grondwater inhoude gebasseer op verwagte klimaatsveranderinge en huidige grondwater toestande.
Water Research Commission

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Siriwardana, Chandawimal H. "CHARACTERIZATION OF PALEOCLIMATE AND MARINE PROCESSES ASSOCIATED WITH HOLOCENE SEDIMENTATION ON THE CHUKCHI MARGIN, ARCTIC OCEAN." Kent State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=kent1406718279.

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Oliveira, Diamantino Figueiredo Rodrigues de. "O risco de inundação urbana nas frentes de água de deltas e estuários em cenários de alterações climáticas. A frente ribeirinha de Lisboa." Master's thesis, ISA, 2013. http://hdl.handle.net/10400.5/6118.

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Mestrado em Arquitectura Paisagista - Instituto Superior de Agronomia
The present climate changes constitute one of the main threats to delta and estuary cities. The rise of the mean sea level and the increase of the intensity and frequency of the precipitation extremes are presently raising the flood risk of these territories, jeopardizing their maintenance and future development. The present work focuses on how these climate change processes can raise the risk of the urban drainage flooding events at the cities waterfronts. The relevance of the problem is reinforced by the present incapacity of the urban drainage systems to follow the needed adaptation, forcing the delta and estuary cities to rethink the management of their storm water outflow. Under this view, the main drainage adaptation strategies and measures are analysed, namely in urban planning and design, and on the benefits of the integration of natural processes. To contextualize the addressed problem, the possible drainage flood impacts over the Lisbon riverfront are analysed. The influence of the climate change processes over the current drainage system and the flood risk of this area are shown, demonstrating the need for integration of the drainage problem in the future urban planning.

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Zaragoza, Martín Francisco Javier. "Development and fluid dynamic evaluation of novel circulating fluidised bed elements for low-temperature adsorption based carbon capture processes." Thesis, University of Edinburgh, 2017. http://hdl.handle.net/1842/25482.

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A methodology for the thermodynamic-kinetic evaluation of circulating systems as TSA carbon capture processes is developed and used in the assessment of a novel CFB configuration against a benchmark (co-current riser). The novel CFB features a counter-current adsorber, a counter-current regenerator and a riser, the latter element playing a double role of solids conveyer and co-current adsorber. The advantages sought by using a counter-current adsorber are not only the more efficient gas-solid contact mode with respect co-current, but also a low pressure drop derived from operation at lower gas velocities and hydrostatic head partially supported on the contactor internals. Knowledge of the adsorption equilibrium alone is sufficient to realise the much higher sorbent circulation rates required by co-current configurations –compared to counter-current– to meet the stringent carbon capture specifications of 90% recovery and 95% purity. Higher solids circulation rates imply higher energy requirements for regeneration, and therefore research and development of co-current gas-solid contactors cannot be justified in terms of searching for energy-efficient post-combustion carbon capture processes. Parallel experimental investigation in the operation and fluid dynamics of cold model CFB rigs is carried out with the purposes of: 1) providing information that may impact the process performance and can be fed into the mathematical model used in the theoretical assessment for more realistic evaluation, and 2) determine gas and solids residence time distributions (RTDs), which are used for the estimation of axial dispersion and comparison with published results in similar systems. Gas RTD data is generated using a tracer pulse injection-detection technique, whereas RTD for the solid phase is studied using positron emission particle tracking (PEPT). The PEPT technique proved to be adequate for the identification of flow regimes in the novel design of the counter-current adsorber, featuring inclined orifice trays. At low gas velocities the particles flow straight down through the tray holes, whereas at higher velocities the particles flow down in zig-zag, increasing the residence time of the particles and reducing the particle axial dispersion, both beneficial in terms of separation efficiency.

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Driscoll, Jessica Margit. "Impacts of Climate Change in Snowmelt-Dominated Alpine Catchments: Development and Assessment of Comparative Methods to Quantify the Role of Dynamic Storage and Subsurface Hydrologic Processes." Diss., The University of Arizona, 2015. http://hdl.handle.net/10150/560860.

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Snowmelt-dominated systems are a significant source of water supply for the Western United States. Changes in timing and duration of snowmelt are predicted to continue under climate change; however, the impact this change will have on water resources is not well understood. The ability to compare hydrologic processes across space and time is critical to accurately assess the physical and chemical response of headwater systems to climate change. This dissertation builds upon previous work by using long-term data from two snowmelt dominated catchments to investigate the response of hydrologic processes at different temporal and spatial scales. First, results from an hourly spatially-distributed energy balance snowmelt model were spatially and temporally aggregated to provide daily, catchment-wide snowmelt estimates, which, along with measured discharge and hydrochemical data were used to assess and compare hydrologic processes which occur on an annual scale in two headwater catchments for an eleven year study period. Second, the magnitude and timing of snowmelt, discharge fluxes and hydrochemical data were used to assess and compare inter-annual catchment response in two headwater catchments for an eleven year study period. Third, a pseudoinverse method was developed to compare mineral weathering fluxes in a series of nested sub-catchments over an eleven year study period. Advances from this work include the use of an independently-created energy balance snowmelt model for spatially-distributed hydrologic input for catchment-scale water balance, application of a quantifiable measure of catchment-scale hydrologic flux hysteresis and the development of a method to quantify and compare mineral weathering reactions between source waters across space and time. These methods were utilized to quantify and assess its role of dynamic storage in mitigating climate change response.

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Menke, Valerie [Verfasser], and Gerhard [Akademischer Betreuer] Schmiedl. "Impacts of short-term climate change and anthropogenic activity on marine ecosystem variability and biogeochemical processes in the Gulf of Taranto (central Mediterranean Sea) / Valerie Menke ; Betreuer: Gerhard Schmiedl." Hamburg : Staats- und Universitätsbibliothek Hamburg, 2018. http://d-nb.info/1156462053/34.

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Grimm-Seyfarth, Annegret [Verfasser], Florian [Akademischer Betreuer] Jeltsch, and Klaus [Akademischer Betreuer] Henle. "Effects of climate change on a reptile community in arid Australia : exploring mechanisms and processes in a hot, dry, and mysterious ecosystem / Annegret Grimm-Seyfarth ; Florian Jeltsch, Klaus Henle." Potsdam : Universität Potsdam, 2017. http://d-nb.info/1218403748/34.

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Baca, Kira J. "Environmental Impacts on the Development and Dune Activity of Oxbow Lake along the Southwest Coast of Lake Michigan at Saugatuck, Michigan USA." University of Toledo / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1365161018.

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Dissertations / Theses on the topic '040104 Climate Change Processes'

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