Decision-makers in cities have realized their pivotal role in addressing climate change, and they are responding accordingly. This thesis presents three papers that explore the process of responding to climate change in cities, highlighting the situation in selected global cities with varying economies and development priorities. The methodology for conducting an urban greenhouse gas inventory in three Chinese cities is detailed in the first paper, illustrating issues of economic development and climate change mitigation in a transitional economy. Next, the greenhouse gas emissions savings of various strategic mitigation plans are quantified for Toronto, demonstrating the aggressive actions needed in developed cities to approach carbon neutrality. The third paper explores issues associated with climate change in three developing cities, emphasizing the need for synergic development incorporating strategies for both mitigation and adaptation. The thesis concludes with an overview of the importance of innovation and further research to future responses to climate change.

Global cities have recognized the need to reduce greenhouse gas (GHG) emissions and have begun to take action to balance of the carbon cycle. This thesis examines the nuances of quantification methods used and the implications of current policy for long-term emissions. Emissions from waste management, though relatively small when compared with building and transportation sectors, are the largest source of emissions directly controlled by municipal government. It is important that municipalities understand the implications of methodological selection when quantifying GHG emissions from waste management practices. The “Waste-in-Place” methodology is presented as the most relevant for inventorying purposes, while the “Methane Commitment” approach is best used for planning. Carbon sinks, divided into “Direct” and “Embodied”, are quantified using the Greater Toronto Area (GTA) as a case study. “Direct” sinks, those whose sequestration processes occur within urban boundaries, contribute the largest share of carbon sinks with regional forests providing a significant proportion. “Embodied” sinks, those whose sequestration processes (or in the case of concrete, the processes that enable sequestration) are independent of the urban boundary, can contribute to the urban carbon pool, but greater uncertainty exists in upstream emissions as the management/processing prior to its use as a sink are generally beyond the consumer’s purview. The Pathways to Urban Reductions in Greenhouse gas Emissions (or PURGE) model is developed as a means to explore emissions scenarios resulting from urban policy to mitigate climate change by quantifying future carbon sources/sinks (from changes in building stock, vehicle stock, waste treatment and urban/regional forests). The model suggests that current policy decisions in the GTA provide short-term reductions but are not sufficient in the long term to balance the pressures of economic and population growth. Aggressive reductions in energy demand from personal transportation and existing building stock will be necessary to achieve long-term emissions targets.

Decision-makers in cities have realized their pivotal role in addressing climate change, and they are responding accordingly. This thesis presents three papers that explore the process of responding to climate change in cities, highlighting the situation in selected global cities with varying economies and development priorities. The methodology for conducting an urban greenhouse gas inventory in three Chinese cities is detailed in the first paper, illustrating issues of economic development and climate change mitigation in a transitional economy. Next, the greenhouse gas emissions savings of various strategic mitigation plans are quantified for Toronto, demonstrating the aggressive actions needed in developed cities to approach carbon neutrality. The third paper explores issues associated with climate change in three developing cities, emphasizing the need for synergic development incorporating strategies for both mitigation and adaptation. The thesis concludes with an overview of the importance of innovation and further research to future responses to climate change.

New Zealand's greenhouse gas inventory is dominated by the agricultural trace gases, CH4 and N2O instead of CO2, which is dominant on a global scale. While the majority of the anthropogenic CH4 is emitted by ruminant animals as a by-product of enteric fermentation, N2O is mainly produced by microbial processes occurring in the soil. In grazed pastoral soils, N2O is generated from N originating from dung, urine, effluent applied to land, biologically fixed N2 and fertiliser. The amount of emission depends on complex interactions between soil properties, climatic factors and management practices. Increased intensification of pastoral agriculture in New Zealand, particularly in dairying has led to an increased production of farm dairy effluent. Traditionally, direct disposal of nutrient rich farm dairy effluents (FDE) into water bodies was an acceptable practice in New Zealand, but with the introduction of the Resource Management Act (1991), discharge of effluents into surface waters is now a controlled activity and many Regional Councils encourage the land irrigation of effluents to protect surface water quality. While the impact of grazing and FDE irrigation on groundwater contamination through leaching and runoff of nutrients has been studied extensively, there has been only limited work done on the effect of these practices on air quality as affected by N2O emission. This thesis examines the effects of various factors, such as compaction due to cattle treading, and the nature, application rate and time of effluent application on N2O emission in relation to the changes in the soil physical properties and C and N transformation from a number of small plot and field experiments. The results were then used, together with data from the literature, to predict the emissions from effluent irrigated pastures using a process-based model. In grazed pastures, animal treading causes soil compaction, which results in decreased soil porosity and increased water filled pore space that stimulate the denitrification rate as well as influence the relative output of N2O and dinitrogen (N2) gases. A field plot study was conducted to determine N2O emission from different N sources as affected by soil compaction. The experiment comprised two main treatments (uncompacted and compacted) to which four N sources (natural cattle urine, potassium nitrate, ammonium sulphate and urea at the rate of 600kg N ha-1) and a control (water only) were applied. Compaction was obtained through driving close parallel tracks by the wheels of the vehicle. The changes in the soils physical properties (bulk density, penetration resistance (PR), soil matric potential and oxygen diffusion rate (ODR) due to the compaction created by the wheel traction of the vehicle were compared with the changes in these properties due to the treading effect of grazing cattle, which was monitored in another field experiment. The N2O fluxes were measured using a closed chamber technique. The compaction at the grazing trial and at the wheel traction experimental plot caused significant changes in soil bulk density, PR, soil matric potential and ODR values. Overall, the bulk density of the compacted soil was higher than the uncompacted soil by 6.7% (end of 3 weeks) and 4.9% (end of 1 week) for the field experiment and the grazing trial, respectively. Results suggest that maximum compaction occurred in the top 0-2 cm layer. Compaction caused an increase in N2O emission, which was more pronounced in the nitrate treatment than in the other N sources. In the case of the compacted soil, 10% of the total N applied in the form of nitrate was emitted, whereas from uncompacted soil this loss was only 0.7%. N2O loss was found to decrease progressively from the time of application of N treatments. Total N2O emission for the three month experimental period ranged from 2.6 to 61.7 kg N2O-N ha-1 for compacted soil and 1.1 to 4.4 kg N2O-N ha-1 for uncompacted soil. In the second field plot experiment, the results of N2O fluxes from treated farm dairy effluent (TFDE), untreated farm dairy effluent (UFDE), treated piggery farm effluent (TPFE) and treated meat effluent (TME) applied to 2m x 1m plots for 'autumn' (February-April) and 'winter' (July-September) are described. Effluent irrigation resulted in higher emissions during both the seasons indicating that the supply of C and N through effluent irrigation contributed to increased N2O emission. The highest emissions were observed from TPFE (2.2% of the applied N) and TME (0.6% of the applied N) during the autumn and winter seasons, respectively. Emissions generated by the TFDE application were the lowest of the four effluent sources but higher than the water and control treatments. The effect of effluent irrigation on N2O emission was higher during the autumn season than the winter season. The effect of key soil and effluent factors such as water filled pore space (WFPS), nitrate, ammonium and available C in soil and effluents on N2O emission was examined using regression equations. The third field plot experiment examined the effect of four TFDE application rates (25mm, 50mm, 75mm and 100mm) on N2O emission. Treatments were added to 2m x 1m plots lined with plastic sheet to restrict the flow of effluent. The N2O emission increased with the increasing effluent loading rate, with the emission ranging from 0.8 to 1.2% of the added N. This can be attributed to the increasing addition of N and C in the soil with the increasing application rate of the effluent. Besides, providing C and N substrates, the effluent application increased the WFPS of the soil, thereby creating conditions conducive for dentrification and N2O emission. A field experiment was conducted at the Massey University No 4 Dairy farm in which N2O emission and related soil and environmental parameters were monitored for two weeks following the TFDE applications over an area of 0.16 ha in September 2003 (21mm), January 2004 (23mm) and February 2004 (16mm). Emissions were measured by a closed chamber technique with 20 chambers for each treatment, in order to cover the variability present in the field. N2O emissions increased immediately after the application of the effluent, and subsequently dropped after about two weeks. The total N2O emitted from the effluent application after the first, second and third irrigation was 2%, 4.9% and 2.5%, respectively of the total N added through the effluent. The higher emission observed during the second effluent irrigation event was due to high soil moisture content during the measurement period. Moreover effluent was applied immediately after a grazing event leading to more N and C input into the soil through excretal deposition. In this experiment the residual effect of effluent application on N2O emission was also examined by monitoring emissions 12 weeks after the effluent application. The emissions from the control and effluent irrigated plots were similar, indicating that there was no residual effect of the effluent irrigation on N2O emissions. In a separate field study, N2O emission was monitored at the Massey University No 4 Dairy farm to examine the effect of a grazing event of moderate intensity on N2O emission. The treatments consisted of a grazed and an ungrazed control. The fluxes from the grazed site were much higher than for the ungrazed site with the total emissions from the former site being 8 times higher than the latter site for the entire experimental period. A modified New Zealand version of denitrification decomposition model (DNDC), a process based model, namely "NZ-DNDC", was used to simulate N2O emission from the TFDE application in the field experiment. The model was able to simulate the emission as well as the WFPS within the range measured in the field. But simulated emissions from the TFDE were slightly lower than measured values. Improvements in the parameterisation for effluent irrigation are likely to further improve the N2O simulations.

abstract: In the U.S., high-speed passenger rail has recently become an active political topic, with multiple corridors currently being considered through federal and state level initiatives. One frequently cited benefit of high-speed rail proposals is that they offer a transition to a more sustainable transportation system with reduced greenhouse gas emissions and fossil energy consumption. This study investigates the feasibility of high-speed rail development as a long-term greenhouse gas emission mitigation strategy while considering major uncertainties in the technological and operational characteristics of intercity travel. First, I develop a general model for evaluating the emissions impact of intercity travel modes. This model incorporates aspects of life-cycle assessment and technological forecasting. The model is then used to compare future scenarios of energy and greenhouse gas emissions associated with the development of high-speed rail and other intercity travel technologies. Three specific rail corridors are evaluated and policy guidelines are developed regarding the emissions impacts of these investments. The results suggest prioritizing high-speed rail investments on short, dense corridors with fewer stops. Likewise, less emphasis should be placed on larger investments that require long construction times due to risks associated with payback of embedded emissions as competing technology improves. / Dissertation/Thesis / M.S. Sustainability 2011

Master of Science / Architectural Engineering and Construction Science / Russell J. Murdock / The purpose of this study is to identify and explore relationships between the building industry, building energy usage, and how both the industry and the energy usage correspond to greenhouse gas (GHG) emissions in the United States. Building energy codes seek to reduce energy usage and, subsequently, GHG emissions. This study specifically seeks to determine the impact that most current U.S. building energy codes could have on national GHG emissions if widespread adoption and enforcement of those codes were a reality. The report initially presents necessary background information about GHG emissions is first discussed. This establishes the current state of global GHG emissions, the position of the U.S. within the global scale, and what portion of the contribution can be attributed to the building industry. The report also describes the current issues and benefits of building energy codes. An overview of building energy codes evaluation is included, with explanation of the energy analysis used to determine the effectiveness of new building energy codes. In order to determine how to improve the building energy code system, an analysis of ANSI/ASHRAE/IES Standard 90.1-2013 (equivalent to 2015 IECC, the most recent standard available) is conducted to reveal unrealized GHG emission reductions that are expected with adoption and compliance to the newest code. Standard 90.1-2013 is analyzed due to the national popularity of the code relative to other building energy codes. This analysis includes compilation of energy usage intensity, square footage, and current code adoption data throughout the United States. Results showed that the excess GHG emission savings from enhanced adoption and compliance was not significant on a national scale. However, in terms of GHG emissions currently saved by building energy codes, the extra savings becomes more significant, proving that increased adoption and compliance is a worthwhile pursuit. Recommendations are then made for how to increase adoption and compliance. This information will give policymakers improved understanding of the current state of the industry when crafting laws regarding GHG emissions and building energy codes. Furthermore, findings from this study could benefit specific states that are attempting to lower GHG emissions.

Thesis (MTech (Information Technology))--Cape Peninsula University, 2016. / Climate change imposes indisputable burdens on economic development by significantly causing damage to the environment. In the transportation sector, carbon dioxide emissions from vehicles are seen as top environmental pollutants around the world and in South Africa. Despite increasing environmental issues, many people, including business leaders, generally think of environmental issues as disconnected from their everyday business lives and behavioural patterns. The Republic of South Africa as a member of the United Nations Framework Convention on Climate Change (UNFCCC) encourages any practices and processes that will control, reduce or prevent anthropogenic emissions of greenhouse gases. The adoption of telecommuting for travel reduction can impact positively on environmental sustainability by reducing the amount of commuter driving and thus reducing carbon emissions. Telecommuting is an arrangement where an employee works from home or out of office using telecommunication links (internet, email and/or telephone) to reduce commuting to and from the office, enhance productivity in the organisation, and reduce office space requirements. However, despite the well documented benefits of telecommuting, the uptake of telecommuting in South Africa is slow. This study falls under the Green Information Technology research field. The aim of the study is to identify the reasons behind the slow adoption of telecommuting in South African organisations. The study followed embedded multiple-case studies. Qualitative data were collected from nine companies using semi-structured interviews with 19 participants comprising of Information Technology (IT) and Human Resource (HR) managers, telecommuters and non-telecommuters. The companies were selected to be as diverse as possible in the operating sector and both purposive and snowball strategies were used.

Over the last couple of decades, sustainability has gained importance in the business world, and a concept that has often been used as a prime example of how to deal with today’s environmental problems is circular economy. Even though the topic is relatively new, there has already been quite some debate about its actual advantages and disadvantages, and while there is as of yet no consensus, the majority argues that the application of circular economy practices will be beneficial for the environment. Which is exactly what this research has attempted to ascertain by looking at 78 firms from a wide range of industries yet all from the Nordic region, since this geographical area has been hailed repeatedly for their sustainability. This was done by performing a hierarchical regression analysis on the data in order to explore a possible relationship between the score of a firm on the benchmark of circular economy practices and its corresponding environmental performance, specifically energy consumption, water usage and greenhouse gas emissions. The hierarchical regression analysis showed a significantly positive relationship between a firm’s score on the benchmark of circular economy practices and its energy consumption, while controlling for firm size, industry, debt ratio,slack resources and country of origin, which was contrary to expectations. No such relationship was found between a firm’s benchmark score and their water usage, the same goes for greenhouse gas emissions. Nevertheless, this research has taken an important step in understanding the relationship between circular economy practices and a firm’s environmental performance, and in doing so has opened up new avenues to explore in terms of future research. While the Nordic region is on the right track, there is still a long road ahead.

Global energy demands are constantly increasing and fossil fuels are a finite resource. The shift towards alternative, more renewable and sustainable fuels is inevitable. Furthermore, the increased emissions of greenhouse gases have forced a pressing need to find cleaner, more environmentally friendly sources of fuel. Biomass energy is a promising alternative fuel because it offers several important advantages. It is a renewable energy form, it comes from many sources and produces biogas (CH4 and CO2). Furthermore, it can have a zero carbon footprint; this is due to the fact that the carbon produced is from the same carbon used to make the biomass. In addition, by replacing fossil fuels, the emissions of CH4 and CO2 (both greenhouse gases) is reduced. Biomass-derived syngas (H2 and CO) can be utilized as a feedstock for many important industrial processes such as methanol synthesis, ammonia synthesis and Fischer-Tropsch synthesis (FTS) to produce long chain hydrocarbon fuels. Municipal solid waste (MSW) biomass is considered as the source of the biomass for this dissertation work. MSW accounts for 20% of man-made methane emissions making it an attractive source for utilization. However, methane reforming to synthesis gas (H2 and CO) typically occurs at temperatures higher than 600°C making it economically challenging at the smaller scale of MSW conversion processes. This dissertation effort focused on formulating low precious metal loaded heterogeneous catalysts that can reform methane at low temperature (T<500°C) making the process more industrially viable. The effect of select contaminants (siloxanes) in the biogas on the reforming catalysts was studied through accelerated poisoning. Finally, the syngas ratio was improved by combining low temperature dry reforming with steam reforming (termed bi-reforming). The catalyst system used for this dissertation study was comprised of 1.34wt%Ni- 1.00wt%Mg on a Ceria-Zirconia oxide support (0.6:0.4 ratio respectively). The catalysts were doped with platinum (0-0.64% by mass) and compared to palladium doped catalysts (0-0.51% by mass). The ratio chosen for the support, Ce0.6Zr0.4, was determined to be the best ratio in terms of activity and surface area by previous studies done in this group [1]. Nickel has been widely studied as methane reforming catalyst [2-6]. Alone, nickel atoms are prone to carbon deposition especially during methane decomposition, however, coupling NiO with MgO helps to reduce carbon deposition by reducing agglomeration of Ni crystallites, thereby improving catalyst lifetime [2, 7]. Furthermore, addition of small amounts of noble metals such as Pt or Pd help to drive the reduction of the catalyst to lower temperatures and enhance catalytic activity. Different metal loadings of Pt and Pd were tested to determine the optimum catalyst that will reform methane at low temperatures, is resistant to deactivation and produces a high syngas ratio (~2:1) which is necessary for processes such as FTS. Preliminary results have shown that in general Pt is superior in this catalyst system for low temperature reforming of methane. It consistently had syngas ratios near the desired ratio compared to Pd, it did not deactivate with extended time on stream and overall had higher turnover frequencies. This catalyst system has potential to make industrial reforming of methane from biomass feedstock more economically viable.

A fuel levy is one of the market-based measures (MBMs) currently under consideration at the International Maritime Organization. MBMs have been proposed to improve the energy efficiency of the shipping sector and reduce its emissions. This paper analyses the economic and environmental implications of two types of levy on shipping bunker fuels by means of an analytical model built on the cobweb theorem. A unit-tax per ton of fuel and an ad-valorem tax, enforced as a percentage of fuel prices, are examined. In both cases, a speed and fuel-consumption reduction equivalent to an improvement in the energy efficiency of the sector would be expected as a result of the regulation enforcement. The speed reduction in the unit-tax case depends on fuel prices and the tax amount, whereas in the ad-valorem case it relies upon the enforced tax percentage. Both schemes lead to industry profit decline, the extent of which depend on the structure of the levy and market conditions. Since there is concern that the costs resulting from the policy will be passed from shipping companies to their customers along the supply chain, the paper dwells on how the costs arising from the enforcement of the levy will be actually allocated between ship-owners and operators, and cargo-owners. In a market characterised by high freight rates and with no or limited excess capacity, a higher percentage of the total tax amount is transferred from ship-owners to shippers. In case of a recession the opposite happens.