• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 2931
  • 443
  • 243
  • 239
  • 219
  • 85
  • 67
  • 60
  • 50
  • 29
  • 24
  • 20
  • 15
  • 13
  • 12
  • Tagged with
  • 5319
  • 5319
  • 1038
  • 666
  • 491
  • 465
  • 446
  • 424
  • 406
  • 391
  • 387
  • 360
  • 343
  • 330
  • 326
  • 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.
101

A historical perspective on wind data: time, space and vector relationships between ship log data and Cape Royal Astronomical Observatory wind data between 1834 and 1854

Brown, Alexa January 2017 (has links)
This dissertation assesses the extent to which data from the Climatological Database for the World's Oceans (CLIWOC) reflect newly digitized historical wind data captured at the Royal Astronomical Observatory (RAO) in Cape Town, South Africa from 1834-1854. This follows the historical precipitation reconstructions for Southern Africa by Hannaford et al. (2015), using wind data from the CLIWOC database. This project also forms part of a bigger project that is recovering and digitising historical instrumental meteorological data for Southern Africa that have never been analysed before. For Southern Africa, the opportunity to compare historical instrumental data seldom arises due to the paucity of reliable data. However, there is an opportunity to analyse and compare two different wind data sources for a twenty-one year cross over period for south western Africa. Wind, as an indicator of atmospheric conditions, has not been assessed extensively in South African, therefore this project fills an academic gap in historical climatology for the region, and provides newly digitised historical data. Digitisation and pre-processing steps ensure that the RAO dataset is comparable to the CLIWOC dataset. This is done by replicating wind direction and speed measurement conversions and formatting (Garcia-Herrera et al., 2005), and by mirroring the available time steps of data in each dataset (eliminating data were the other dataset has erroneous or missing data). Spatially scattered data recorded over the sea compared to data recorded at a fixed position introduces inherent limitations, error and noise into the data comparison. Therefore, to eliminate as many uncertainties as possible and minimise the noise in the data, the CLIWOC data are refined further by a) a single observation per day, b) separating three regions of differing seasonal synoptic air flow regimes (west coast, south west peninsula and south coast) and c) all analyses based on seasonally grouped data. Temporal, spatial and vector relationships are established for each season using scatter plot graphs and Pearson correlations. The different relationships between the data are derived from corresponding wind data (i.e. data of the same day and time), in each dataset for wind speed and wind direction separately. No significant correlation (all p values>0.05) or signal is evident over time, or as the difference in distance changes. However, seasonality is represented consistently in the wind vector distribution heat maps. Significant findings include the observations of anomalous north westerly winds in summer at the RAO, where the CLIWOC data did not pick up similar data for the corresponding region on the west coast. Historical wind data used herein prove to be reliable by the expected seasonal synoptic flow patterns and characteristics seen in each study region. There is no correlation between the datasets over time and space and the data do not present any clear signals or return events over time. Although corresponding data do not show any correlations, there are typical synoptic flow regimes in each study region which prove that wind data was recorded correctly. Therefore, the datasets are mutually exclusive, but accurate in their intrinsic value. It is only the anomalous summer north westerlies at the RAO which question the reliability of the data, as the same wind regimes were not identifiable in the corresponding CLIWOC data. This anomaly was noted but not studied further. This project highlights the major inconsistencies and limitations in the CLIWOC data. Researchers in the future should use CLIWOC data appropriately to suit the research question and be aware of the inconsistencies that may introduce noise.
102

Ethical consumption among Cape Town students: a qualitative study

McMahon, Molly January 2016 (has links)
Much of current research on ethical consumption biases the North - South relationship of Northern consumers being considered ethical based on their purchasing of items from Southern producers. This establishes the dominant perspective of ethics needing to be expressed toward the distant other and to be based in a specific object, often typified by Fair Trade. These conditions of ethics have led to the assumption that Southern consumers lack ethics in their consumption. Thus this research seeks to expand the current understanding of ethical consumption to include ethics at home and ethics of care, as well as expand the demographic of ethical consumption studies to include Southern consumers. The aim of this research is to add to the developing understanding of Southern ethical consumption through the exploration of ethics in grocery shopping among students. Students from various universities in the Cape Town area were observed while grocery shopping and interviewed about their shopping habits and their thoughts on ethics and values, particularly in terms of consumption and food. Twenty - eight students were interviewed, and of those, 23 were also observed shopping. At the conclusion of this study, it is evident that students, as Southern consumers, do express ethical consideration in their consumption habits. This is based on both perspectives of ethical goods and ethical practices. However, they are more apt to act on the ethics of care at home than on the ethics of care at a distance. The strongest trends among students are thrift, care at home and care for self, as well as a significant draw toward s shopping local and supporting local producers based in their communities and nationally. The implications of this research are that it adds to the literature through its theorization within the Global South, its focus on ethical consumption as a practice instead of solely object - based and the discussion of students as a research demographic. Overall, this study demonstrates how Southern consumers do express ethics in their shopping choices particularly through care at home.
103

Reimagining Climate Change: Visualizing the Future of Sustainability

Unknown Date (has links)
The world’s path to climate change is inevitable. Activists and legislators, all around the world, are actively working to slow down this process or stop changes. Technology is moving toward a sustainable future of renewable energy and resources to lighten the impact that the human population has on the climate. Whether or not these efforts will slow down the changing climate is unknown, but the world’s scientists, engineers, and designers are preparing for any scenario that comes our way. This thesis uses graphic design to visualize the future of humanity adapting to climate change. Topics that are explored include controlled-environment agriculture, vertical farming, sustainable food production, advancements in the medical industry, advancements in transportation, and sustainable energy production. These elements will come together, in my projects, to visualize one possible future of living in Arizona, where living conditions have become inhospitable for life as we know today. / Includes bibliography. / Thesis (M.F.A.)--Florida Atlantic University, 2020. / FAU Electronic Theses and Dissertations Collection
104

Vulnerability of horticulture producers to climate variability and change : the case of Chókwe District, Mozambique

Vilissa, Delfim Julio January 2016 (has links)
Climate change is projected to have continued and globally severe environmental, economic and socioeconomic effects. These effects are forecast to be more severe in the agriculture sector, considering that it is one of the most sensitive industries to climate change. Studies from the Mozambican National Institute for Disaster Management (INGC) suggest that Mozambique is among the countries highly vulnerable to climate change due to its geographical location, in the coastal zone. In addition, the majority of its population is entirely dependent on agriculture activities for food and income. For example, in the Chókwe district, tomato production plays a key role in farmers' livelihood; however, this district is prone to weather variability and climate stresses, affecting the region's agricultural performance and making farmers' livelihood even more precarious. There is indeed limited information on this vulnerability, how farmers cope with the risks as well as their need to manage these stresses. The study conducted includes a survey of 43 farmer households in two villages of Chókwe: Massavasse and Muianga. The study then compares farmers' perceived effects of climate variability with actual climate data observed between 1980 and 2012. Meteorological data was analyzed using R software.
105

Climate change impacts and farmers' responses in Chilanga District, Zambia

Kinkese, Theresa January 2017 (has links)
Climate change and variability are predicted to threaten agricultural production in Southern Africa. For example, Zambia's agriculture remains vulnerable to climate change and variability due to the small-scale farmers' dependence on rain-fed agriculture. Some studies in Zambia have shown the quantitative negative impacts of climate variability on agriculture; however, there is limited knowledge on how farmers perceive the impacts and adapt their agricultural systems. To fill in the knowledge gap mentioned above, the aim of the present study was to evaluate farmers' observations of climate variability impacts and their responses. The study then evaluates the integration of farmers' climate variability observations and adaptation strategies into local district plans. Such integration is deemed critical to ensure agricultural strategies promoted by extension officers are locally relevant and are adopted by the farmers. The study is based on semi-structured interviews and literature review. Thirty-one (31) farmers from Mwembeshi, Chilanga District, Zambia, participated in the study. The findings of the survey indicate that farmers in Mwembeshi are aware of their vulnerability to climate variability impacts. As a result of the observed impacts, they have developed several adaptation strategies. Through this study, extension agents were also interviewed in order find out what adaptation strategies are promoted to the farmers. The findings of the research indicate agricultural extension agents follow national agricultural adaptation strategies (top-down approach). As a result, local agricultural development plans would not specifically integrate/respond to climate variations impacts observed by the farmers. In order to engage local farmer impacts of the climate variability and their adaptation strategies into the local plans, the research suggests a more flexible (or bottom-up) approach to local development planning. Such an approach would allow the integration of local farmer observations of climate variability and their adaptation strategies into district plans. The study also found that extension agents have limited knowledge of climate variability and change, which negatively affects knowledge transfer to farmers on the subject. Therefore, training the extension officers in the subject would most likely increase farmers' knowledge on climate variability and adaptation decision.
106

Environmental concern, knowledge, and the enactment of environmental citizenship in a retail food environment: an investigation into the perceptions and behaviours of Cape Town consumers

Ractliffe, Tamzin Pascoe January 2015 (has links)
Sustainable consumption has long been recognised as essential for the achievement of sustainable development. Whilst early efforts to achieve sustainable consumption focused on using technological innovation and process efficiencies to reduce the resource intensity of products, create new, less toxic, more environmentally friendly products, and/or improve the efficiency of production processes, the inadequacy of production-based approaches alone has been widely accepted. More recent efforts to achieve sustainable consumption have highlighted that a change in the behaviour of individuals is a prerequisite for its achievement. A significant body of research has focusing on trying to understand the determinants of pro-environmental behaviour and specifically the intersection of environmental concern and environmental knowledge in the manifestation in pro-environmental behaviour. The relatively recent concept of environmental citizenship, premised on the existence of concern and knowledge, and rooted in issues of environmental and social justice, has gained traction as an alternative means by which to achieve both sustainable development and sustainable consumption. This dissertation presents research findings from a mixed-method empirical study of the food consumption behaviour of a purposive sample of upper middle income South African retail food consumers. Applying the notion of environmental citizenship, it considers the influence of critical variables widely identified as key to the expression of pro-environmental behaviour, viz. desire to act, knowledge to act, and ability to act. Specifically it considers the relationship between environmental knowledge, environmental concern and pro-environmental behaviour, as well as the barriers and situational factors in the food retail environment which are reported to inhibit the practice of sustainable consumption behaviour. It then considers whether improvements in objective knowledge have an impact on the enactment of environmental citizenship through an increase in pro-environmental behaviour practices. The main conclusion drawn from the findings of this dissertation is that environmental concern and knowledge are positive predictors of pro-environmental behaviour. However, a low incidence of pro-environmental behaviour was evident in the study sample overall. This is most likely as a result of low levels of environmental concern and general lack of objective knowledge although a significant additional barrier could be the lack of a mature market for sustainable food in South Africa. In keeping with international studies, health concerns appear to be both most prevalent and most influential in determining the practice of pro-environmental behaviours. The study also suggests that efforts to increase levels of objective knowledge may have an impact on the practice of sustainable food consumption behaviours.
107

Low carbon energy transitions for informal settlements: a case study of iShack South Africa

Glasser, Zachariah January 2017 (has links)
The majority of informal settlements in South Africa do not have access to reliable, safe, and clean energy. Infrastructural constraints, poor service delivery, the inapt application of policy, and the financial constraints of those living in informal settlements all contribute towards this problem of energy poverty. This dissertation argues that low carbon energy transitions, such as solar home systems, are a viable means for overcoming issues of energy poverty in informal settlements. This dissertation examines the role of urban experimentation in implementing low carbon energy transitions within informal settlements in South Africa, through exploring interactions between policy, technology and justice. The iShack Project (improved Shack) is used as a case study, to identify, analyse, and discuss the ways in which solar home systems have resulted in social and financial changes amongst the residents in Enkanini, Stellenbosch. These relate to changing fuel use patterns, reducing shack fire risk and addressing issues of access and affordability. Multilevel perspective (MLP) and the political ecology approach are the two analytical tools used to discuss the broader conditions that give rise to transitions, as well as providing a more in-depth look at the experiences of those making up the 'social' aspect of socio-technical transitions. These analytical tools informed a series of interviews, which is the primary method through which data was gathered, by highlighting prominent components of agency and power - providing greater understanding of the lived realities of the Enkanini residents. The interviewing process provided an opportunity for residents of Enkanini to voice their opinions on this urban experiment and discuss the impact iShack has had on their lives. Photographs accompany many of the findings in this dissertation and provide a valuable lens through which the lived reality of the Enkanini residents can be more accurately represented. Using the case study of the iShack Project in Enkanini, the findings of this dissertation highlight that policy, technology and justice come to positively reinforce one another in addressing the issue of energy poverty in South Africa. For example, the granting of the Free Basic Electricity (FBE) subsidy to the iShack Project has made it possible for the intermediary to address justice issues, such as the poor being able to access and afford reliable, safe, and clean electricity. Furthermore, iShack's technological innovations, such as "Flash" and the "Flash wallet" have brought about foundational changes in some values, goals, operational procedures and decision-making processes taking place in the community - especially around the notion of monetary savings. This also points to the fact that these technological innovations are physical manifestations of policy itself. The findings show that low carbon energy transitions can be a viable means of overcoming energy poverty in informal settlements and addressing issues of access and affordability for the poor. However, local government plays an important role in being able to adapt local policy in such a way that it creates an enabling environment for an intermediary to be supported or strengthened in this.
108

Sustainable urban agriculture: a sustainable adaptation strategy for the City of Cape Town? : Practices and views on sustainable urban agriculture and climate change in Cape Town

Anaïs, Marie January 2017 (has links)
This work explores the narratives associated with the benefits of sustainable urban agriculture areas in terms of adaptation to climate change in the Cape Town Metropolitan Area, South Africa. Urbanization and climate change are stressing urban areas in developing countries. Therefore, finding a development path towards "sustainable adaptation" remains a critical matter for humanity. Adaptation is sustainable only if it takes into consideration climate risks, while maximizing both social justice and environmental integrity. Urban agriculture is defined in this dissertation as the urban and peri-urban locations where agricultural practices, either the production of crops, livestock, or fish, utilize urban resources for the purpose of selling and consuming these goods produced locally, supporting the urban economy and providing a supply of food for urban citizens. Sustainable urban agriculture encompasses urban agricultural areas operating towards the satisfaction of human food, the preservation of environmental resources, the economic viability of agriculture and the enhancement of the quality of life of farmers, farm workers, and society. This research reviews the practices and views of urban agriculture stakeholders in Cape Town on sustainable urban agriculture to determine if the practices of urban agriculture could be a part of a sustainable adaptation strategy. The methods used to answer this question included a systematic review of studies on urban agriculture worldwide since 1980, and a review of the urban agriculture and adaptation to climate change policies which are implemented at the metropolitan level, all supported and tested through interviews with key informants. Non-Government Organization (NGO)-based community farming initiatives such as Oranjezicht City Farm, Abalimi Bezekhaya or the ERF 81, independent farmers, municipal and provincial government representatives were interviewed. A critical discourse analysis method was utilized to analyze the findings. The study found that the narratives at the metropolitan level, including the policies and the views of governmental representatives, remains focused on the food security contribution whereas the practitioners' narrative expressed an interest in the economic opportunities and social benefits that sustainable urban agriculture can bring, as stated by the literature on sustainable urban agriculture. The key practitioners and NGOs narratives suggest that sustainable urban agriculture is contributing to the adaptive capacity of the farmers as they are using practices such as permaculture or organic farming, which allow them to cope with the impacts of climate variability and climate change. If sustainable farming practices were emphasized instead of farming practices towards small-scale, home-based activity to improve households' food security, the adaptation framework at the municipal and provincial level would be aligned with practitioners and NGOs narratives and would contribute to the sustainable adaptation capacity of the city. The recent shift within the City of Cape Town towards the broad concept of resilience could bridge the gap between current policy and practices, and informants' narratives, but it remains too soon for this to be tested. This study concludes suggesting that the analysis of the informants' and literature's narratives on sustainable urban agriculture express potential to contribute to climate change adaptation and the reduction of vulnerability in Cape Town but alignment between policy and practitioners' needs, wants and actions needs to take place.
109

The thermal tolerances and preferences of native fishes in the Cape Floristic Region: towards understanding the effect of climate change on native fish species

Reizenberg, Jody-Lee January 2017 (has links)
Global climate change models indicate that a rise in temperature and reduction in rainfall in the Western Cape Province of South Africa is inevitable and unavoidable. Within the Western Cape lies the Cape Floristic Region (CFR); a biodiversity hotspot with high levels of endemism. This includes its freshwater fish assemblage. Whereas the current greatest threats to native fish biodiversity are habitat degradation and invasion by non-native species, predicted climate change is likely to further impact fish communities negatively. As a master abiotic variable in aquatic ecosystems; temperature influences the fitness, behaviour, and life-histories of aquatic biota. Thermal alteration may therefore affect sensitive fish species. The upper thermal limit, determined via the critical thermal method, has been validated as a measure of thermal sensitivity. To better understand the impacts of climate change on the native fish of the CFR, upper thermal limits (critical thermal maxima/CTmax) were determined for seven native species of freshwater fish. Thermal preferences were also determined for five of these species using the acute gradient tank approach to elucidate thermal habitat preferences. Species that were identified by the IUCN as vulnerable, endangered, or critically endangered were selected from the four main families of native fish in the CFR (Anabantidae, Austroglanidae, Cyprinidae, and Galaxiidae), from four Rivers. Overall, Cape galaxias (Galaxias zebratus), Breede River redfin (Pseudobarbus burchelli), Berg River redfin (Pseudobarbus burgi), Clanwilliam redfin (Pseudobarbus calidus), and fiery redfin (Pseudobarbus phlegethon) were found to be most sensitive to increased temperature (CTmax= 29.8-32.7⁰C). Clanwilliam rock-catfish (Austroglanis gilli) and Cape kurper (Sandelia capensis) were found to be moderately sensitive (CTmax= 33.0-35.3⁰C). Similar trends were found using the thermal preference approach as CTmax and thermal preference were found to correlate well. The results were related to in-situ water temperature, which influenced both parameters. Thermal tolerances and preferences of all the native species exceed that of invasive salmonids (Onchorynchus mykiss and Salmo trutta). However, non-native centrarchids (Micropterus spp.) are more thermally tolerant, indicating an increase in threat by warm adapted non-natives. These data suggest that species interactions and distributions are likely to undergo substantial changes in response to elevated water temperature.
110

Using micro-finance services to support climate change adaptation among small-scale farmers : identifying opportunities and challenges in southern Mozambique

Mutimba, Egídio Artur Alfredo January 2016 (has links)
Microfinance organisations represent a potential opportunity to promote adaptation of smallholder farmers. Without access to credit, this group of farmers has few opportunities to invest in adequate technologies and practices required to respond to climate variability and change. In this context, this study explores how Microfinance Institutions (MFIs) can be capacitated in order to assist smallholder farmers to respond to climate change. The core objective of the study is to identify opportunities and needs to foster smallholders' adaptation through MFIs. The study is informed by a survey involving 13 MFIs operating in Southern Mozambique. This paper finds that although MFIs are aware that climate risks affect their services in regards to a wider rural economy, these organisations do not have explicit policies to deal with climate risks. It also finds that majority of MFIs' managers recognise the potential for mainstreaming climate variability and change into services they provide to smallholders. However, for MFIs to achieve this they will require training of agents in climate related knowledge and adaptation, better access to climate related information, assistance in aspects of planning taking into consideration climate related risks and clear understanding of the benefits of investing in adaptation.

Page generated in 0.0905 seconds