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Climate change leadership : a study of climate change corporate governance within the mining sectorMzenda, Venantio 06 May 2010 (has links)
The purpose of the study was to contribute to the body of knowledge regarding the corporate sectors’ ability to operate within a carbon constrained society through the institutionalisation of effective corporate governance principles and practices. The research attempted to answer the question: To what extent and under what circumstances should corporate governance influence corporate response to climate change? Climate change risks impact on long-term sustainability of businesses and the competitiveness of some nations. The level of impact of climate change risk to a company is subject to a number of factors, including the nature of its business, the impact of local and international legislation, and the company’s ability to respond to climate change. South Africa is not isolated from climate change risks. Its mining sector is vulnerable to climate change because it is an energy intense sector, and coal is particularly vulnerable to carbon constrain legislation. The study was based on a qualitative research methodology where secondary data were sourced from company documents. The study showed that, on average, mining companies need to improve their climate change corporate governance mechanisms and practices. It was also shown that some of the companies have good systems in place. / Dissertation (MBA)--University of Pretoria, 2010. / Gordon Institute of Business Science (GIBS) / unrestricted
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A glacial sedimentary system in northwest SpitzbergenCromack, Marianne January 1991 (has links)
The record of climate change in Signedalen and Krossfjorden, northwest Spitsbergen, since the Late Weichselian glacial maximum, has been constructed using an integrated analysis of lacustrine, terrestrial and marine sediments. Thirty-four piston cores were taken from two series of linked lakes in Signedalen, fed by three small cirque glaciers. Six further cores were taken from the fjord inlet, Signehamna, into which meltwater from the linked glacier-fed lakes and a further two glaciers drain. Signehamna drains into Lilliehookfjorden, which with Mollerfjorden, combines to form Krossfjorden, from which 16 .cores were made available. Cores were analysed for moisture content, loss-on-ignition, bulk density, grain size, magnetic susceptibility, infra-red stimulated luminescence, by X-radiography and by radioisotopic dating methods, 210Pb and 14C. Bathymetric maps were constructed following echo sounding survey of the lakes. Seventy-two water samples from the linked lakes were used to assess contemporary environmental conditions, and to aid interpretation of sedimentary structures within core sediments. Results of lichenometric survey of moraine ridges and pro-talus deposits in and around Signedalen were analysed using discriminant analysis, and compared with Werner's (1988) lichen growth curve in order to establish a chronology of moraine stabilisation. Seismic records of Krossfjorden have revealed evidence of glacier advance at least as far as the sill separating Krossfjorden from the outer parts of the fjord and shelf associated with the Late Weichselian glacial maximum (Sexton et al., in press). Overlying the basal unit of a possible till , or sediments associated with rapid glacier retreat, is a blanket of homogeneous sediment formed by ice-distal deposition during the Holocene. There is no evidence of Younger Dryas glacier expansion preserved in the marine sediments, or in terrestrial moraines. Denudation rates calculated from lacustrine sediment accumulation infer the presence of smaller glaciers in Signedalen during the Younger Dryas than at present. The early to mid Holocene appears to have been characterised by relatively warm conditions, with much reduced glacier presence in Signedalen. Evidence of Neoglacial cooling, between approximately 3,000 yr BP and 1,500 yr BP, is found in lichenometric recorckof talus deposits, although precise dating of the inception, and duration of this cooling is problematic. No moraine sediments are recorded from this period. The Little Ice Age maximum, dated by licheno~etry to AD 1890, was the most extensive glacier advance to have affected the cirque glaciers of Signedalen and the tidewater glaciers of Krossfjorden, and is associated with the highest denudation rates recorded in the lacustrine sediments. It also appears to have been responsible for the formation of rock glaciers within the protalus deposits of Signedalen. Since this date, a general retreat of glaciers has been interrupted periodically by still-stands or slight readvances when climatic conditions deteriorated.
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An investigation into the impact of greenhouse gas forcings on the terrestrial radiation field : sensitivity studies at high spectral resolutionBrindley, Helen Elizabeth January 1998 (has links)
No description available.
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Field and Modelling Investigations of Permafrost Conditions in Labrador, Northeast CanadaWay, Robert January 2017 (has links)
The Permafrost Map of Canada shows the region of Labrador in northeast Canada as spanning conditions from continuous permafrost in the north to isolated patches in the south. However, few studies have documented this and the most detailed field information comes from research in the 1960s and 1970s, with contemporary permafrost distribution largely unexamined. An extensive investigation of contemporary permafrost conditions throughout Labrador and portions of northeastern Québec was undertaken between 2013 and 2017 to fill this knowledge gap. A multi-scale approach to analyzing permafrost distribution was employed, including collection of detailed field information at selected sites, establishment of climate and ground monitoring apparatus at more than 35 different locations and spatial numerical permafrost modelling of permafrost conditions across the region. Spatio-temporal infilling was used with thin plate spline interpolation to generate temporally-consistent climate grids for 1948-2016 at a monthly resolution for all of Labrador-Ungava. Evaluation of derived air temperature grids against meteorological observations and remote field monitoring stations showed an overall accuracy of 0.8 ± 0.3 °C on a monthly timescale. The grids were used to generate freezing and thawing degree-days maps to facilitate permafrost modelling.
Field investigations in the coastal barrens of southeastern Labrador (51.5°N to 54°N) used geophysics (DC electrical resistivity tomography), standard field methods and ground temperature monitoring to characterize very isolated patches of permafrost observed to be up to 8 m thick beneath palsas and peat plateaus. Permafrost was inferred to be absent in wetland, forested and forest-tundra areas inland, notwithstanding average air temperatures lower than at the coast. However, field investigations undertaken farther north in the coastal community of Nain, NL (56.3°N) showed permafrost to be present at numerous sites within the community in tundra, forested and disturbed settings. Boreholes and geophysics showed permafrost less than 20 m thick at several locations including beneath existing and proposed building locations. These investigations of permafrost along a latitudinal gradient highlight the contrasting permafrost environments found in coastal regions of Labrador.
Field data from monitoring stations across Labrador (n=83) were used to analyze the interrelationships of key variables in permafrost modelling. Snow depth, not mean annual air temperature, was the strongest single determinant of mean temperatures at the ground surface and at ~1 m depth. Ground temperature variability was most related to land cover class with a critical late-winter snow depth of 70 cm or less inferred to be sufficient to prevent the formation of permafrost at the monitoring sites. Testing of several different land cover datasets for permafrost model parameterization gave errors in ground surface temperature ranging from ±0.9 to ±2.1°C. A new estimate of the distribution of permafrost at high resolution (250 m x 250 m) was generated for all of Labrador-Ungava using a modified version of the temperature at the top of permafrost model. Predicted ground temperatures for long-term climate normal ranged regionally from -9°C (for high elevations in northern Québec) to +5°C (for southeastern Labrador-Québec). Modelling of permafrost for specific temporal windows (1948-1962; 1982-1996; 2000-2014) suggested that permafrost area increased from the middle of the 20th Century to a potential peak extent (36% of the total land area) in the 1990s. Subsequent warming is predicted to have caused a decrease in permafrost extent of one-quarter (95 000 km2) even if air temperatures rise no further, providing air and ground temperatures equilibrate.
The field observations in this thesis validated research conducted in the interior of Labrador during 1970s which directly linked permafrost presence or absence to snow thickness. Permafrost was more widespread than would be expected in coastal areas based on the region’s mean annual air temperatures which suggests that specific geomorphologic and meteorological settings may allow permafrost to persist in otherwise unsuitable regions. Land cover type, through its influence on snow distribution, was shown to be a key variable whose changes must be considered when examining future permafrost conditions in the region.
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Quantifying CO2 emissions from shipping and the mitigation potential of wind power technologyTraut, Michael January 2014 (has links)
Responsible for CO2 emissions of the order of 1 Gt, about 2-3 % of the global total, the shipping sector is part of the challenge to reduce emissions, in order to avoid dangerous climate change. Aiming to inform the sector’s response to the challenge, this research addresses two knowledge gaps. Current methods of estimating carbon emissions from shipping are subject to large uncertainties and lacking with respect to a set of greenhouse gas accounting criteria. Based on Automatic Identification System (AIS) data, a new methodology is developed to monitor fuel consumption and ensuing carbon emissions around the globe. Results from applying the method to a sample fleet of 13 vessels and validating it against fuel consumption records covering a time interval of one year demonstrate that, for the first time, estimating shipping emissions from individual ship AIS movement data has become possible at the global scale. Lacking information on the performance of carbon abatement technologies is the second knowledge gap. Due to its geographical and temporal variability, wind power technology is particularly dependent on a transparent assessment to exploit its carbon saving potential as a freely available and renewable energy source. Numerical performance models of two wind power technologies - a Flettner rotor and a towing kite - are combined with wind velocity data from a weather model to calculate their propulsive power contribution. Average results along five analysed sample routes range between 0.3 MW and 1.0 MW for a single Flettner rotor andbetween 0.1 MW and 0.9 MW for the modelled towing kite. Both methodologies are ready for further use. Applying the AIS-based method to data covering the world fleet may provide a concise, up-to-date view of greenhouse gas emissions from shipping when and where they take place. The wind power technology model can be applied to any shipping route around the world. Next steps towards fully exploring and optimising the potential of wind power technology are outlined. A better understanding of greenhouse gas emissions from shipping and of mitigation options gained from applying the models may, in turn, contribute to the sector’s successful response to the climate change challenge.
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The Effects of Carbon Dioxide Fertilization on the Ecology of Tropical Seagrass CommunitiesCampbell, Justin E 20 June 2012 (has links)
Increasing atmospheric CO2 concentrations associated with climate change will likely influence a wide variety of ecosystems. Terrestrial research has examined the effects of increasing CO2 concentrations on the functionality of plant systems; with studies ranging in scale from the short-term responses of individual leaves, to long-term ecological responses of complete forests. While terrestrial plants have received much attention, studies on the responses of marine plants (seagrasses) to increased CO2(aq) concentrations remain relatively sparse, with most research limited to small-scale, ex situ experimentation. Furthermore, few studies have attempted to address similarities between terrestrial and seagrass responses to increases in CO2(aq). The goals of this dissertation are to expand the scope of marine climate change research, and examine how the tropical seagrass, Thalassia testudinum responds to increasing CO2(aq) concentrations over multiple spatial and temporal scales.
Manipulative laboratory and field experimentation reveal that, similar to terrestrial plants, seagrasses strongly respond to increases in CO2(aq) concentrations. Using a novel field technique, in situ field manipulations show that over short time scales, seagrasses respond to elevated CO2(aq) by increasing leaf photosynthetic rates and the production of soluble carbohydrates. Declines in leaf nutrient (nitrogen and phosphorus) content were additionally detected, paralleling responses from terrestrial systems. Over long time scales, seagrasses increase total above- and belowground biomass with elevated CO2(aq), suggesting that, similar to terrestrial research, pervasive increases in atmospheric and oceanic CO2(aq) concentrations stand to influence the productivity and functionality of these systems. Furthermore, field experiments reveal that seagrass epiphytes, which comprise an important component of seagrass ecosystems, additionally respond to increased CO2(aq) with strong declines in calcified taxa and increases in fleshy taxa.
Together, this work demonstrates that increasing CO2(aq) concentrations will alter the functionality of seagrass ecosystems by increasing plant productivity and shifting the composition of the epiphyte community. These results have implications for future rates of carbon storage and sediment production within these widely distributed systems.
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R&D portfolio analysis of low carbon energy technologies to reduce climate change mitigation costsZdybel, Rose M 01 January 2013 (has links)
In this dissertation we analyze the effects of low carbon energy technology R&D portfolios on the cost of climate change mitigation. We use the results to create the analytical foundation for a decision support system aimed at effectively communicating the effects of uncertainty to decision makers. Specifically, we focus on three main areas. The first is generating a correlated probability distribution around detailed energy price forecasts. The second is showing how the availability of advanced energy technologies and combinations of them affect the marginal abatement cost curve. The third is creating the analytic foundation for a decision support system (DSS) by using an integrated assessment model to analyze the effects of combinations of low carbon energy technologies on CO2 concentration stabilization costs and then combining the results with probabilistic data from expert elicitations to analyze R&D portfolios. The third part also involves creating a multivariate regression model to represent the relationship between variables for additional analysis.
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Life on the edge: do body size and drinking dependency influence how birds deal with the heat in South Africa's most extreme desert?Orolowitz, Matthew January 2020 (has links)
Climate change-induced increases in air temperature pose a substantial risk to birds inhabiting arid environments. Terrestrial endotherms, such as birds, can respond to high temperatures by moving to cooler microsites, increasing heat dissipation behaviour and/or suppressing activity. Previous studies have suggested that larger bird species may have a greater suppression of activity (e.g. foraging) than smaller species at high air temperatures. However, this body mass effect may be confounded by drinking behaviour, since different species have diverse drinking ecologies. Using four species of lark that inhabit the Tankwa Karoo National Park, I investigated whether foraging activity and other heat-influenced behaviours were influenced by body mass or drinking behaviour when comparisons were constrained within a single family. These lark species were: Red-capped Lark (24 g), Spikedheeled Lark (25 g), Karoo Lark (29 g) and Large-billed Lark (45 g). There was a two-fold difference in body mass between the lightest (Red-capped Lark) and the heaviest (Large-billed Lark). Moreover, two of these lark species drink surface water (drinking larks; Red-capped and Large-billed Lark) and two do not (non-drinking larks; Spike-heeled and Karoo Lark). I also collected data on other passerines present in the Tankwa Karoo for comparison to the larks. Black bulb thermometers were used to measure the thermal landscape and a combination of instantaneous scan samples and focal observations to record bird behaviour. Black bulb temperatures were as much as 8.16 °C cooler in shaded than in sunny locations. Similarly, black bulb temperatures were as much as 8.02 °C cooler off the ground than on the ground. The results from scan sample data showed limited support that foraging was negatively correlated (although non-significant) with mass between lark species as temperatures increased; however, data from focal observations suggested larks that obtain all water from food had a greater reduction in foraging as temperatures increase than larks that drink free surface water. Within scan samples, heat dissipation and shade-seeking behaviour appeared to be more strongly influenced by whether the species drinks free surface water or not than by differences in body mass. Furthermore, drinking larks dissipate heat at lower temperatures and seek shade at higher temperatures than non-drinking larks. Foraging intensity was higher in the sunny microsites as compared to shaded microsites for all species, suggesting that drinking larks might gain an energetic benefit due to increased heat tolerance. Therefore, non-drinking species may be vulnerable to foraging-thermoregulation trade-offs under climate change. However, ongoing drying trends in the Tankwa Karoo and reduced availability of surface water may make drinking species more vulnerable to climate change in the future than non-drinking species.
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“1,5℃ to Stay Alive” - Climate Justice Discourse and Climate Change Denial Discourse in Climate Change PoliticsVuori, Vappu January 2019 (has links)
Climate change as a global phenomenon threatens human rights and causes social injustices. This thesis examines the genealogies of climate justice discourse and climate change denial discourse in the context of international climate change politics. The aim is to understand the construction of and the correlation between the discourses and how the discourses relate to human rights. The thesis employs discourse analysis with a conception of climate justice and a neoclassical realist theory applied to climate change politics. Climate justice discourse is found to interact with chiefly moral and political terms, whereas the denial discourse interacts mainly with economic and scientific terms. Consequently, there is a lack of interaction between the discourses as they operate in different levels of communication and it has, to some extent, caused stalemate in climate change politics. Additionally, while climate justice discourse makes use of the human rights framework, the denial discourse undermines it.
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Time-use and wellbeing in Onesi, NamibiaMusingarabwi, Steffanie January 2016 (has links)
Men's and women's time-use in relation to wellbeing is well-investigated and understood within the context of the developed world. There has been limited research into the gendered experiences of time-use and three dimensional (3D) wellbeing in rural communities of sub-Saharan Africa and particularly so in semi-arid areas. As a result, failure to appreciate how time-use and wellbeing are experienced by the rural population in semi-arid areas impedes a full understanding of how rural inhabitants spend their time and how this makes them worse off or better off in different aspects of their wellbeing. This subsequently challenges the appropriateness of efforts to improve the lived experience of rural inhabitants. The study aimed to make a contribution to the knowledge gap on time-use and wellbeing by assessing how time-use relates to the experiences of material, subjective and relational aspects of wellbeing in a semi-arid area. It hypothesised that if men and women who are household-heads spend their time-use differently this has implications on their experiences of material, subjective and relational wellbeing. The study adopted a quantitative approach to primary data collection, analysis and interpretation of results. A questionnaire survey consisting of 93 randomly selected male and female headed households was conducted using stratified sampling techniques. Data was analysed using Microsoft Excel and SPSS software including regression analysis and statistical tests (Mann Witney U test) from which descriptive and statistical results were presented in tables and graphs following regression analysis. The study yielded several findings including the importance of personal care for improved subjective wellbeing despite the trade-off with material wellbeing; the importance of age and social grants for ensuring a better experience of material wellbeing; the importance of social connections particularly for widows and widowers; as well as the significance of time spent on leisure and work-outside for improving relational wellbeing. In addition, women's disproportionally high time spent on domestic work leaves them feeling subjectively worse-off while the persistence of traditional gender role division seems to have a determining effect on the time-use and wellbeing experiences of household-heads in the study area. Overall, the study highlights time-use related opportunities and constraints for improving the wellbeing of rural inhabitants in Onesi, Namibia.
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