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Description
Overall, biofuels play a significant role in future energy sourcing and deserve thorough researching and examining for their best use in achieving sustainable goals. National and state policies are supporting biofuel production as a sustainable option without a holistic view of total impacts. The analysis from this research connects to

Overall, biofuels play a significant role in future energy sourcing and deserve thorough researching and examining for their best use in achieving sustainable goals. National and state policies are supporting biofuel production as a sustainable option without a holistic view of total impacts. The analysis from this research connects to policies based on life cycle sustainability to identify other environmental impacts beyond those specified in the policy as well as ethical issues that are a concern. A Life cycle assessment (LCA) of switchgrass agriculture indicates it will be challenging to meet U.S. Renewable Fuel Standards with only switchgrass cellulosic ethanol, yet may be used for California's Low Carbon Fuel Standard. Ethical dilemmas in food supply, land conservation, and water use can be connected to biofuel production and will require evaluation as policies are created. The discussions around these ethical dilemmas should be had throughout the process of biofuel production and policy making. Earth system engineering management principles can help start the discussions and allow anthropocentric and biocentric viewpoints to be heard.
ContributorsHarden, Cheyenne (Author) / Landis, Amy E. (Thesis advisor) / Allenby, Braden (Committee member) / Khanna, Vikas (Committee member) / Arizona State University (Publisher)
Created2014
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Description
Life Cycle Assessment (LCA) is used in the chemical process sector to compare the environmental merits of different product or process alternatives. One of the tasks that involves much time and cost in LCA studies is the specification of the exact materials and processes modeled which has limited its widespread

Life Cycle Assessment (LCA) is used in the chemical process sector to compare the environmental merits of different product or process alternatives. One of the tasks that involves much time and cost in LCA studies is the specification of the exact materials and processes modeled which has limited its widespread application. To overcome this, researchers have recently created probabilistic underspecification as an LCA streamlining method, which uses a structured data classification system to enable an LCA modeler to specify materials and processes in a less precise manner. This study presents a statistical procedure to understand when streamlined LCA methods can be used, and what their impact on overall model uncertainty is. Petrochemicals and polymer product systems were chosen to examine the impacts of underspecification and mis-specification applied to LCA modeling. Ecoinvent database, extracted using GaBi software, was used for data pertaining to generic crude oil refining and polymer manufacturing modules. By assessing the variation in LCA results arising out of streamlined materials classification, the developed statistics estimate the amount of overall error incurred by underspecifying and mis-specifying material impact data in streamlined LCA. To test the impact of underspecification and mis-specification at the level of a product footprint, case studies of HDPE containers and aerosol air fresheners were conducted. Results indicate that the variation in LCA results decreases as the specificity of materials increases. For the product systems examined, results show that most of the variability in impact assessment is due to the differences in the regions from which the environmental impact datasets were collected; the lower levels of categorization of materials have relatively smaller influence on the variance. Analyses further signify that only certain environmental impact categories viz. global warming potential, freshwater eutrophication, freshwater ecotoxicity, human toxicity and terrestrial ecotoxicity are affected by geographic variations. Outcomes for the case studies point out that the error in the estimation of global warming potential increases as the specificity of a component of the product decreases. Fossil depletion impact estimates remain relatively robust to underspecification. Further, the results of LCA are much more sensitive to underspecification of materials and processes than mis-specification.
ContributorsMurali, Ashwin Krishna (Author) / Dooley, Kevin (Thesis advisor) / Dai, Lenore (Thesis advisor) / Nielsen, David (Committee member) / Arizona State University (Publisher)
Created2014
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Description
Natural rubber and rubber products can be produced from the guayule plant (Parthenium argentatum Gray), which is a low input perennial shrub native to Mexico and the American Southwest. Guayule rubber has the potential to replace Hevea (Hevea brasiliensis) rubber, the most common natural rubber, and synthetic rubber, which is

Natural rubber and rubber products can be produced from the guayule plant (Parthenium argentatum Gray), which is a low input perennial shrub native to Mexico and the American Southwest. Guayule rubber has the potential to replace Hevea (Hevea brasiliensis) rubber, the most common natural rubber, and synthetic rubber, which is derived from petroleum, in a wide variety of products, including automobile tires. Rubbers make up approximately 47% of the analyzed conventional passenger tire's weight, with 31% from synthetic rubber and 16% from natural Hevea rubber. Replacing the current rubber sources used for the tire industry with guayule rubber could help reduce dependency on imported rubber in addition to reducing greenhouse gas emissions. Moreover, residues from guayule rubber are being researched as a bioenergy feedstock to further improve the environmental footprint of guayule rubber products. This study used life cycle assessment (LCA), a useful tool to determine environmental impacts from a product or process, to quantify and compare environmental impacts of the raw material extraction, transportation and manufacturing of a conventional and a guayule rubber based passenger tire. The impact results of this comparative LCA identified the major environmental impacts and contributing process and informed how the impacts from the tire production can be reduced through utilization of natural rubber co-products as electricity off-sets and reducing guayule rubber's environmental impacts through agricultural and transportation modifications. Results showed that tire raw material extraction contributed the majority of impacts in all categories, where the production of guayule rubber for guayule tires, and the production of synthetic rubber for conventional tires, were the main contributors. Guayule rubber impacts occurred mainly from electricity consumption for agricultural irrigation, while synthetic rubber is a petroleum-based material resulting in high impacts. Transportation impacts had little significance compared to other stages in the life cycle, except for smog impacts, which occurred mainly from truck transport for guayule tires, and transoceanic transport for conventional tires. Tire manufacturing impacts occurred mainly from electricity use in the facilities and were reduced with the use of guayule rubber in guayule tires.
ContributorsRasutis, Daina (Author) / Landis, Amy E. (Thesis advisor) / Colvin, Howard (Committee member) / Seager, Thomas P. (Committee member) / Arizona State University (Publisher)
Created2014
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Description
As climate change becomes a greater challenge in today's society, it is critical to understand young people's perceptions of the phenomenon because they will become the next generation of decision-makers. This study examines knowledge, beliefs, and behaviors among high school students. The subjects of this study include students from high

As climate change becomes a greater challenge in today's society, it is critical to understand young people's perceptions of the phenomenon because they will become the next generation of decision-makers. This study examines knowledge, beliefs, and behaviors among high school students. The subjects of this study include students from high school science classes in Phoenix, Arizona, and Plainfield, Illinois. Using surveys and small group interviews to engage students in two climatically different locations, three questions were answered:

1) What do American students know and believe about climate change? How is knowledge related to beliefs?

2) What types of behaviors are students exhibiting that may affect climate change? How do beliefs relate to behavioral choices?

3) Do climate change knowledge, beliefs, and behaviors vary between geographic locations in the United States?

The results of this study begin to highlight the differences between knowledge, beliefs, and behaviors around the United States. First, results showed that students have heard of climate change but often confused aspects of the problem, and they tended to focus on causes and impacts, as opposed to solutions. Related to beliefs, students tended to believe that climate change is caused by both humans and natural trends, and would affect plant and animal species more than themselves and their families. Second, students were most likely to participate in individual behaviors such as turning off lights and electronics, and least likely to take public transportation and eat a vegetarian meal. Individual behaviors seem to be most relevant to this age group, in contrast to policy solutions. Third, students in Illinois felt they would be more likely to experience colder temperatures and more precipitation than those in Arizona, where students were more concerned about rising temperatures.

Understanding behaviors, motivations behind beliefs and choices, and barriers to actions can support pro-environmental behavior change. Educational strategies can be employed to more effectively account for the influences on a young person's belief formation and behavior choices. Providing engagement opportunities with location-specific solutions that are more feasible for youth to participate in on their own could also support efforts for behavior change.
ContributorsKruke, Laurel (Author) / Larson, Kelli (Thesis advisor) / Klinsky, Sonja (Committee member) / White, Dave (Committee member) / Arizona State University (Publisher)
Created2015
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Description
Ground coupled heat pumps (GCHPs) have been used successfully in many environments to improve the heating and cooling efficiency of both small and large scale buildings. In arid climate regions, such as the Phoenix, Arizona metropolitan area, where the air condi-tioning load is dominated by cooling in the summer,

Ground coupled heat pumps (GCHPs) have been used successfully in many environments to improve the heating and cooling efficiency of both small and large scale buildings. In arid climate regions, such as the Phoenix, Arizona metropolitan area, where the air condi-tioning load is dominated by cooling in the summer, GCHPs are difficult to install and operate. This is because the nature of soils in arid climate regions, in that they are both dry and hot, renders them particularly ineffective at dissipating heat.

The first part of this thesis addresses applying the SVHeat finite element modeling soft-ware to create a model of a GCHP system. Using real-world data from a prototype solar-water heating system coupled with a ground-source heat exchanger installed in Menlo Park, California, a relatively accurate model was created to represent a novel GCHP panel system installed in a shallow vertical trench. A sensitivity analysis was performed to evaluate the accuracy of the calibrated model.

The second part of the thesis involved adapting the calibrated model to represent an ap-proximation of soil conditions in arid climate regions, using a range of thermal properties for dry soils. The effectiveness of the GCHP in the arid climate region model was then evaluated by comparing the thermal flux from the panel into the subsurface profile to that of the prototype GCHP. It was shown that soils in arid climate regions are particularly inefficient at heat dissipation, but that it is highly dependent on the thermal conductivity inputted into the model. This demonstrates the importance of proper site characterization in arid climate regions. Finally, several soil improvement methods were researched to evaluate their potential for use in improving the effectiveness of shallow horizontal GCHP systems in arid climate regions.
ContributorsNorth, Timothy James (Author) / Kavazanjian, Ed (Thesis advisor) / Redy, T. Agami (Committee member) / Zapata, Claudia (Committee member) / Arizona State University (Publisher)
Created2014
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Description
With the projected population growth, the need to produce higher agricultural yield to meet projected demand is hindered by water scarcity. Out of many the approaches that could be implemented to meet the water gap, intensification of agriculture through adoption of advanced agricultural irrigation techniques is the focus for this

With the projected population growth, the need to produce higher agricultural yield to meet projected demand is hindered by water scarcity. Out of many the approaches that could be implemented to meet the water gap, intensification of agriculture through adoption of advanced agricultural irrigation techniques is the focus for this research. Current high water consumption by agricultural sector in Arizona is due to historical dominance in the state economy and established water rights. Efficiency gained in agricultural water use in Arizona has the most potential to reduce the overall water consumption. This research studies the agricultural sector and water management of several counties in Arizona (Maricopa, Pinal, and Yuma). Several research approaches are employed: modeling of agricultural technology adoption using replicator dynamics, interview with water managers and farmers, and Arizona water management law and history review. Using systems thinking, the components of the local farming environment are documented through socio-ecological system/robustness lenses. The replicator dynamics model is employed to evaluate possible conditions in which water efficient agricultural irrigation systems proliferate. The evaluation of conditions that promote the shift towards advanced irrigation technology is conducted through a combination of literature review, interview data, and model analysis. Systematic shift from the currently dominant flood irrigation toward a more water efficient irrigation technologies could be attributed to the followings: the increase in advanced irrigation technology yield efficiency; the reduction of advanced irrigation technology implementation and maintenance cost; the change in growing higher value crop; and the change in growing/harvesting time where there is less competition from other states. Insights learned will further the knowledge useful for this arid state's agricultural policy decision making that will both adhere to the water management goals and meet the projected food production and demand gap.
ContributorsBudiyanto, Yoshi (Author) / Muneepeerakul, Rachata (Thesis advisor) / Smith, Karen (Committee member) / Abbott, Joshua (Committee member) / Arizona State University (Publisher)
Created2014
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Description
The rise of meat consumption in the United States has been dramatic over

the past half century due to demographic changes. The increase in meat is visible in Mexico as well due to expanding economic interest in cattle production plus increased population and rising incomes. The worst consequences of our modern

The rise of meat consumption in the United States has been dramatic over

the past half century due to demographic changes. The increase in meat is visible in Mexico as well due to expanding economic interest in cattle production plus increased population and rising incomes. The worst consequences of our modern food system are in factory farming of animals, which requires a greater amount of resources than for producing grains, fruits, and vegetables. The specific effects of meat consumption highlight the importance of understanding humans as actors in the food system. In order to explore the drivers of consumer food and meat choice, my research answered the two questions: What factors influence meat consumption? and How do cultural and social norms influence decisions to consume certain types and amounts of meat?

Qualitative interviews were conducted with Mexican-American respondents between age 20 and 29 as the population of interest because of their regional dominance in the study area of Tempe, AZ and because of the high prevalence of meat in their cultural diets. Looking at millennials in particular is crucial because as the first generation born with technology and Internet as constants, they have formed unique characteristics like openness to change and new perspectives. My sample population communicated motivations and constraints to their overall consumption patterns and the frequency and types of meat consumed.

This study found that cost and convenience were the driving factors behind food choice, given the hectic schedules of the sample population, who were mostly students at Arizona State University. Culture played an important role in respondents' heavy meat consumption given their exposure to meat's centrality in traditional Mexican meals. Acculturation did not play an extensive role because prominent Mexican culture in the Southwest U.S. allowed respondents' families access to traditional food while living in the US. The lack of sustainability knowledge and its connection to food choice indicates the importance of marketing that contextualizes decreased meat consumption. Rather than focusing solely on environmental outcomes, marketing tools highlighting health, financial, and economic benefits of eating less meat would encourage more consumers to decrease consumption.
ContributorsNamugayi, Deborah (Author) / Larson, Kelli L (Thesis advisor) / Klinsky, Sonja (Committee member) / Redman, Erin (Committee member) / Arizona State University (Publisher)
Created2014
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Description
The production of nanomaterials has been increasing and so are their applications in various products, while the environmental impacts and human impacts of these nanomaterials are still in the process of being explored. In this thesis, a process for

producing nano-titanium dioxide (nano-TiO2) is studied and a case-study has been

The production of nanomaterials has been increasing and so are their applications in various products, while the environmental impacts and human impacts of these nanomaterials are still in the process of being explored. In this thesis, a process for

producing nano-titanium dioxide (nano-TiO2) is studied and a case-study has been conducted on comparative Life Cycle Assessment (LCA) of the application of these nano-TiO2 particles in the sunscreen lotion as a UV-blocker with the conventional organic chemical sunscreen lotion using GaBi software. Nano-TiO2 particles were identified in the sunscreen lotion using Transmission Electron Microscope suggesting the use of these particles in the lotion.

The LCA modeling includes the comparison of the environmental impacts of producing nano-TiO2 particles with that of conventional organic chemical UV-blockers (octocrylene and avobenzone). It also compares the environmental life cycle impacts of the two sunscreen lotions studied. TRACI 2.1 was used for the assessment of the impacts which were then normalized and weighted for the ranking of the impact categories.

Results indicate that nano-TiO2 had higher impacts on the environment than the conventional organic chemical UV-blockers (octocrylene and avobenzone). For the two sunscreen lotions studied, nano-TiO2 sunscreen variant had lower environmental life cycle impacts than its counterpart because of the other chemicals used in the formulation. In the organic chemical sunscreen variant the major impacts came from production of glycerine, ethanol, and avobenzone but in the nano-TiO2 sunscreen variant the major impacts came from the production of nano-TiO2 particles.

Analysis further signifies the trade-offs between few environmental impact categories, for example, the human toxicity impacts were more in the nano-TiO2 sunscreen variant, but the other environmental impact categories viz. fossil fuel depletion, global warming potential, eutrophication were less compared to the organic chemical sunscreen variant.
ContributorsThakur, Ankita (Author) / Dooley, Kevin (Thesis advisor) / Dai, Lenore (Committee member) / Lind, Mary Laura (Committee member) / Arizona State University (Publisher)
Created2014
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Description
Targeted growth is necessary for sustainable urbanization. There is a pattern in China of rapid development due to inflated projections. This creates "ghost towns" and underutilized urban services that don't support the population.

In the case of Taiyuan, this industrial third-tier city of 4.2 million people. A majority of the newer

Targeted growth is necessary for sustainable urbanization. There is a pattern in China of rapid development due to inflated projections. This creates "ghost towns" and underutilized urban services that don't support the population.

In the case of Taiyuan, this industrial third-tier city of 4.2 million people. A majority of the newer residential services and high-end commercial areas are on the older, eastern side of the city. Since 2007, major urban investments have been made in developing the corridor that leads to the airport, including building a massive hospital, a new sports stadium, and "University City". The intention of the city officials is to encourage a new image of Taiyuan- one that is a tourist destination, one that has a high standard of living for residents. However, the consequences of these major developments might be immense, because of the required shift of community, residents and capital that would be required to sustain these new areas. Much of the new development lacks the reliable and frequent public transit of the more established downtown areas.

Do these investments in medical complexes, sports stadiums and massive shopping centers create new jobs that impact the income disparity, or do these new areas take years to fill, creating vacuums of investment that remove funding from areas with established communities? Can Taiyuan move successfully to a post-industrial economy with these government interventions, or is it too much too soon?

By examining demographic data from 2000, 2007, 2009, 2011, and 2013, research on sustainability assessments in Chinese cities (Lu Jia), and translated government publications detailing the urbanization efforts in Taiyuan, I will assess the results of the urbanization changes instituted by the new mayor, Geng Yanbo. My thesis will evaluate the success and failures of these policies and the implications for Taiyuan.
ContributorsDolins, Sarah-Laura (Author) / Webster, Douglas (Thesis advisor) / Golub, Aaron (Committee member) / Cai, Jianming (Committee member) / Arizona State University (Publisher)
Created2014
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Description
The sacred San Francisco Peaks in northern Arizona have been at the center of a series of land development controversies since the 1800s. Most recently, a controversy arose over a proposal by the ski area on the Peaks to use 100% reclaimed water to make artificial snow. The current state

The sacred San Francisco Peaks in northern Arizona have been at the center of a series of land development controversies since the 1800s. Most recently, a controversy arose over a proposal by the ski area on the Peaks to use 100% reclaimed water to make artificial snow. The current state of the San Francisco Peaks controversy would benefit from a decision-making process that holds sustainability policy at its core. The first step towards a new sustainability-focused deliberative process regarding a complex issue like the San Francisco Peaks controversy requires understanding the issue's origins and the perspectives of the people involved in the issue. My thesis provides an historical analysis of the controversy and examines some of the laws and participatory mechanisms that have shaped the decision-making procedures and power structures from the 19th century to the early 21st century.
ContributorsMahoney, Maren (Author) / Hirt, Paul W. (Thesis advisor) / Tsosie, Rebecca (Committee member) / White, Dave (Committee member) / Arizona State University (Publisher)
Created2011