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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
801

A Hitchhiker’s Guide to Climate Change Leadership : An Educational Design Research exploration of a sustainability course at Uppsala University

May, Friederike January 2015 (has links)
Considering the ever-increasing impacts of climate change, the responsibility to take leadership lies with many actors; one of them being universities. The course in “Climate Change Leadership – Power, Politics and Culture” at CEMUS/Uppsala University explores the issue from a participatory perspective where students play a significant role in exploring what climate change leadership means throughout one semester. By using an educational design research approach this paper contributes to the further development of the course by giving a definition for climate change leadership as a theoretical outcome, and suggesting improvements for the course development as a practical outcome. To do so a theoretical analysis of leadership and change theories has been undertaken, as well as an analysis of data collected by current and former students, and course coordinators that have worked with the course before. The given definition and suggestions for the course will be subject to critical scrutiny in the upcoming spring semester and are subject to change depending on their efficacy in contributing to leadership capabilities in students.
802

Agricultural water demand assessment in the Southeast U.S. under climate change

Braneon, Christian V. 08 June 2015 (has links)
This study utilized (a) actual measured agricultural water use along with (b) geostatistical techniques, (c) crop simulation models, and (d) general circulation models (GCMs) to assess irrigation demand and the uncertainty associated with demand projections at spatial scales relevant to water resources management. In the first part of the study, crop production systems in Southwest Georgia are characterized and the crop simulation model error that may be associated with aggregated model inputs is estimated for multiple spatial scales. In the second portion of this study, a methodology is presented for characterizing regional irrigation strategies in the Lower Flint River basin and estimating regional water demand. Regional irrigation strategies are shown to be well represented with the moisture stress threshold (MST) algorithm, metered annual agricultural water use, and crop management data. Crop coefficient approaches applied at the regional scale to estimate agricultural water demand are shown to lack the interannual variability observed with this novel approach. In the third portion of this study, projections of regional agricultural demand under climate change in the Lower Flint River basin are presented. GCMs indicate a range of possible futures that include the possibility of relatively small changes in irrigation demand in the Lower Flint River basin. However, most of the GCMs utilized in this work project significant increases in median water demand towards the end of this century. In particular, results suggest that peak agricultural water demands in July and August may increase significantly. Overall, crop simulation models are shown to be useful tools for representing the intra-annual and interannual variability of regional irrigation demand. The novel approach developed may be applied to other locations in the world as agricultural water metering programs become more common.
803

Environmental Change and Place-Based Identities: Sponge Fishing in Tarpon Springs, Florida

Suver, Michael 01 January 2012 (has links)
Abstract As the environmental consequences of urbanization and climate change become apparent in coastal communities, it has become important to understand how residents of these communities experience and approach their changing environments. This becomes especially significant in places where nature-based livelihoods constitute a major part of the economy. This thesis focuses on the city of Tarpon Springs, located along the Gulf of Mexico in Florida, where sea sponge fishing is an important contributor to the local economy while also being central to place-based tourist and ethnic identities. It seeks to understand how environmental changes in the sea sponge economy will affect the coastal economy of Tarpon Springs. Based on interviews conducted with people closely connected with the sponge fishing economy, including sponge fishers and shops selling sponges, the thesis delves into (i) local perspectives on changing environmental conditions, (ii) how such changes will impact the future of sponge fishing and (iii) the extent to which local governmental support has been sought by sponge fishers and shops. Sponge fishing in Tarpon Springs is connected to its Greek identity so changes in the sponge economy could potentially affect whether tourist experiences which highlight Greek identity linked to sponge fishing continue to be connected to an actual Greek economic presence or reflect nostalgia for a Greek past. The interview responses showed concerns about declining sponge hauls which were connected to more immediate experiences of environmental change and pollution, including red tide events and phosphate runoff. Respondents also reflected on how climate change will exacerbate such environmental issues through rising water temperatures. Respondents viewed Tarpon Springs as a community with a strong Greek identity and sponge shop owners especially seemed to be dependent on links with an active sponge fishing economy to enhance the value of their sponges for tourists. In terms of government support, those involved in the sponge economy had very little interaction with city officials and did not seem keen to enhance such interactions. This thesis thus reveals that the economy of Tarpon Springs continues to be shaped by sponge fishing livelihoods that are directly dependent on nature. However, it seems that concerns related to environmental change remain within the local community and are not being voiced through more public forums, such as through active engagement with local government. The future of Tarpon Springs and its sponge fishing economy therefore remains uncertain, even as local participants in the sponge economy continue to work towards maintaining their unique identity.
804

Growth and Herbivory of the Black Mangrove, <i>Avicennia germinans</i>, Along a Salinity Gradient

Neveu, Danielle 01 January 2013 (has links)
Coastal communities will be most affected by global climate change and are important to study to understand current and future ecological processes. The current model for global climate change predicts a change in rainfall, which will alter the salinity of coastal systems. Given the presence of eutrophication in many coastal waters, it is important to understand the effects that this increase in nutrients, coupled with changes in salinity, will have on these communities. This study was conducted to understand the effect of salinity increase on the growth and herbivory of the black mangrove, Avicennia germinans, in the presence of increased nutrients. Explicitly, the effects of changing salinity (high, medium, and low) were coupled with fertilizer additions of nitrogen, phosphorus, both, or no fertilizer. Nutrient enrichment differentially affected the growth and herbivory of the plants between salinity zones. The medium salinity zone consistently produced the greatest increases in growth and herbivory. Added nutrients did not have an effect on growth in the low salinity zone. However, added nitrogen increased some growth variables in the medium salinity zone and added phosphorus increased some growth variables in the high salinity zone. Phosphorus also increased herbivory. The results point to diverse processes acting along the salinity gradient. There appears to be differential N- and P-limitation along the gradient. Additionally, the growth differences indicate abiotic and biotic limitations across the salinity gradient, with debilitating salinity acting in the high salinity zone and competition acting in the low salinity zone.
805

Beyond the annual book sale : a model for an environmentally sustainable post-weeding process / Model for an environmentally sustainable post-weeding process

Halpern, Rebecca Katharine 15 August 2012 (has links)
Social activism is a foundation in librarianship. As community stewards,librarians regularly develop solutions to complex social issues from discrimination in the workplace to open source academic publishing. Increasingly, one of those issues is climate change. As the reality of climate change becomes more apparent, libraries are faced with their role in supporting healthy communities and environmental sustainability through activities like reducing carbon emissions. There has been much work on how to build greener collections and improve library facilities, but little attention has been paid to the role of weeding—specifically, what happens to deaccessioned materials. The Austin (Texas) Public Library developed an innovative, creative, and long-term model for recycling their core commodity. The Recycled Reads bookstore offers a useful example of how an urban library system recycles weeded print and media materials in such a way that 100 percent of their materials are diverted away from landfills. Through stakeholder buy-in and working closely with community and corporate partners, Austin Public Library's Recycled Reads facility is a model any library system could adopt to address environmentally responsible weeding policies. / text
806

Assessing GCM performance for use in greenhouse gas forced climate change predictions using multivariate empirical orthogonal functions

Picton, Jeffrey 26 November 2012 (has links)
Due to factors such as spatial discretization and the parameterization of certain processes, the presence of bias in models of the Earth's atmosphere is unavoidable. Whether we are selecting a model to explain past phenomenon, forecast weather patterns, or make inferences about the future, the target of any selection process is to minimize the discrepancies between model output and observations. Some discrepancies have a greater effect on the scatter of model predictions though. We exemplify this in the case of CO2 forced warming using multivariate empirical orthogonal functions (EOF), created using an ensemble of plausible parameter configurations of CAM3.1. When subjecting this ensemble to a doubling of atmospheric CO2, some EOFs exhibit significantly higher correlation than others with the resulting increase in mean global surface temperature. Therefore, there are discernible bias patterns that effect its predictive scatter. By targeting these patterns in the model evaluation process, it is plausible to use this information to constrain the resulting range of predictions. We take a first step towards showing this by creating a metric to evaluate model skill based on these EOFs and their correlation to a model's sensitivity to CO2 forcing. Using model output, for which we know the resulting temperature increase, as a surrogate for observations in this metric, the resulting distribution of skill scores indeed agreement in sensitivity to CO2 forcing. / text
807

Future projections of daily precipitation and its extremes in simulations of 21st century climate change

Yin, Lei 15 April 2014 (has links)
The current generation of climate models in the Coupled Model Intercomparison Project Phase 5 (CMIP5) is used to assess the future changes in daily precipitation and its extremes. The simple average of all the models, i.e. the multi-model ensemble mean (MMEM), has been widely used due to its simplicity and better performance than most individual models. Weighting techniques are also proposed to deal with the systematic biases within the models. However, both methods are designed to reduce the uncertainties for the study of climate mean state. They will induce problems when the climate extremes are of interest. We utilize a Bayesian weighting method to investigate the rainfall mean state and perform a probability density function based assessment of daily rainfall extremes. Satellite measurement is used to evaluate the short historical period. The weighting method can be only applied to regions rather than hemispheric scale, and thus three tropical regions including the Amazon, Congo, and Southeast Asia are studied. The method based on the Gamma distribution for daily precipitation is demonstrated to perform much better than the MMEM with respect to the extreme events. A use of the Kolmogorov-Smirnov statistic for the distribution assessment indicates the method is more applicable in three tropical wet regions over land mentioned above. This is consistent with previous studies showing the Gamma distribution is more suitable for daily rainfall in wet regions. Both methods provide consistent results. The three regions display significant changes at the end of the 21st century. The Amazon will be drier, while the Congo will not have large changes in mean rainfall. However, both of the Amazon and Congo will have large rainfall variability, implying more droughts and floods. The Amazon will have 7.5% more little-rain days (defined as > 0.5 mm/d) and 4.5 mm/d larger 95th percentile for 2092-2099, and the Congo will have 2.5% more little-rain days and 1 mm/d larger 95th percentile. Southeast Asia will be dryer in the western part and wetter in the eastern part, which is consistent with the different changes in the 5th percentile. It will also experience heavier rainfall events with much larger increases in the 95th percentile. The future changes, especially the increase in rainfall extremes, are very likely associated with the strengthening of hydrological cycle. / text
808

Atmospheric emissions and air quality impacts of natural gas production from shale formations

Zavala Araiza, Daniel 10 September 2015 (has links)
Natural gas is at the core of the energy supply and security debates; new extraction technologies, such as horizontal drilling and hydraulic fracturing, have expanded natural gas production. As with any energy system, however, natural gas has an environmental footprint and this thesis examines the air quality impacts of natural gas production. Greenhouse gas (GHG), criteria pollutant, and toxic emissions from natural gas production have been subject to a great amount of uncertainty, largely due to limited measurements of emission rates from key sources. This thesis reports direct and indirect measurements of emissions, assessing the spatial and temporal distributions of emissions, as well as the role of very high emitting wells and high emitting sources in determining national emissions. Direct measurements are used to identify, characterize and classify the most important sources of continuous and episodic emissions, and to analyze mitigation opportunities. Methods are proposed and demonstrated for reconciling these direct measurements of emissions from sources with measurements of ambient concentrations. Collectively, the direct source measurements, and analyses of ambient air pollutant measurements in natural gas production regions reported in this work improve the estimation, characterization, and methods for monitoring air quality implications of shale gas production. / text
809

Internal displacementdue to natural disasters : Inclusion of IDPs in Disaster Risk Reduction strategies

Grohe, Christine Lea January 2015 (has links)
The increasing impacts of climate change bear new challenges for the international community. The exacerbation of natural disasters in frequency and scope also confronts the national governments with newly arising problems. Disaster-induced displacement isan increasing phenomenon occurring the last years, which particularly vulnerable regions with a high exposure to national hazards are affected by. The present study addresses the inclusion of disaster IDPs in Disaster Risk Reduction frameworks on international and national level and argues that there is a need to recognize disaster-induced displacement as an increasing issue that should explicitly be addressed and included in policy frameworks on both levels. This was addressed through analyzing international and national key strategies in Disaster-Risk-Reduction. A case comparison of the earthquake in Haiti in 2010 and the yearly recurring floods in Mozambique since 2000 illustrates the implementation of these frameworks in regard to the issue of displacement. Although efforts have been made on both levels to improve the situation of IDPs in the response and recovery phase, it is argued that an inclusion through a community-based approach is needed in all the phases of disaster management to appropriately address the needs of disaster IDPs in the pre-and post-disaster phases.
810

Effects of Educational Attainment on Climate Risk Vulnerability

Striessnig, Erich, Lutz, Wolfgang, Patt, Anthony January 2013 (has links) (PDF)
In the context of still uncertain specific effects of climate change in specific locations, this paper examines whether education significantly increases coping capacity with regard to particular climatic changes, and whether it improves the resilience of people to climate risks in general. Our hypothesis is that investment in universal primary and secondary education around the world is the most effective strategy for preparing to cope with the still uncertain dangers associated with future climate. The empirical evidence presented for a cross-country time series of factors associated with past natural disaster fatalities since 1980 in 125 countries confirms this overriding importance of education in reducing impacts. We also present new projections of populations by age, sex, and level of educational attainment to 2050, thus providing an appropriate tool for anticipating societies' future adaptive capacities based on alternative education scenarios associated with different policies. (authors' abstract)

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