Matching Items (12)

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Mapping Urban Water Insecurity: A Case Study of Homelessness in Phoenix, Arizona, U.S.A.

Description

In this project we examine the geographical availability of water resources for persons experiencing homelessness in Phoenix, Arizona, U.S.A. Persons experiencing homelessness spend a significant portion of their time outdoors

In this project we examine the geographical availability of water resources for persons experiencing homelessness in Phoenix, Arizona, U.S.A. Persons experiencing homelessness spend a significant portion of their time outdoors and as such have a higher risk of dehydration, heat-related illness, and heat stress. Our data was collected using archival data, participant- observation, focal follows with water distributors that serve homeless populations, phone and internet surveys with social service providers, and expert interviews with 14 local service providers. We analyzed this data using methods for thematic coding and geospatial analysis. We find that the sources of water and geographic availability vary across the economic sectors of the population and that they become more unconventional and more difficult to access with further isolation. We conclude that many persons who are experience homelessness have inconsistent and unreliable access to water for hydrating, maintaining hygiene, cooking and cleaning for reasons that are largely due to geographic inaccessibility.

Contributors

Created

Date Created
  • 2016-12

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Controlling Exhaust Pipe Temperatures: An Environmental Concern

Description

The temperature of exhaust pipes can be dangerous in dry areas where there is a lot of brush. The temperatures of exhaust pipes can reach a high enough temperature to

The temperature of exhaust pipes can be dangerous in dry areas where there is a lot of brush. The temperatures of exhaust pipes can reach a high enough temperature to start a fire if touching the dry brush, which ignites around 300°C. The goal of this project was to explore different techniques to limit the possibility of these brush fires. Specifically, different methods were explored to reduce the temperature of the pipe that would be contacting the brush. Fires can begin within seconds of contacting the hot exhaust pipes [10]. This experiment found that of the three options tested: exhaust wrap, heat sink with thermoelectric devices, and high temperature paint, adding a heat shield/sink is the best way to limit the high temperatures from igniting the brush. There was a cooling difference of nearly 100°C when a heat shield/sink was added to the bare pipe. The additional thermal mass as well as the finned heat sinks attached to the heat sink helped dissipate the heat from the pipe and release the waste heat into the surroundings. The increase in surface area in correspondence with forced convection from the surrounding air lowered the temperature of the metal in contact with the dry brush.

Contributors

Agent

Created

Date Created
  • 2020-05

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Sky View Factors from Synthetic Fisheye Photos for Thermal Comfort Routing—A Case Study in Phoenix, Arizona

Description

The Sky View Factor (SVF) is a dimension-reduced representation of urban form and one of the major variables in radiation models that estimate outdoor thermal comfort. Common ways of retrieving

The Sky View Factor (SVF) is a dimension-reduced representation of urban form and one of the major variables in radiation models that estimate outdoor thermal comfort. Common ways of retrieving SVFs in urban environments include capturing fisheye photographs or creating a digital 3D city or elevation model of the environment. Such techniques have previously been limited due to a lack of imagery or lack of full scale detailed models of urban areas. We developed a web based tool that automatically generates synthetic hemispherical fisheye views from Google Earth at arbitrary spatial resolution and calculates the corresponding SVFs through equiangular projection. SVF results were validated using Google Maps Street View and compared to results from other SVF calculation tools. We generated 5-meter resolution SVF maps for two neighborhoods in Phoenix, Arizona to illustrate fine-scale variations of intra-urban horizon limitations due to urban form and vegetation. To demonstrate the utility of our synthetic fisheye approach for heat stress applications, we automated a radiation model to generate outdoor thermal comfort maps for Arizona State University’s Tempe campus for a hot summer day using synthetic fisheye photos and on-site meteorological data. Model output was tested against mobile transect measurements of the six-directional radiant flux density. Based on the thermal comfort maps, we implemented a pedestrian routing algorithm that is optimized for distance and thermal comfort preferences. Our synthetic fisheye approach can help planners assess urban design and tree planting strategies to maximize thermal comfort outcomes and can support heat hazard mitigation in urban areas.

Contributors

Agent

Created

Date Created
  • 2017-03-27

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Vulnerability to heat stress in urban areas: a sustainability perspective

Description

Extreme hot-weather events have become life-threatening natural phenomena in many cities around the world, and the health impacts of excessive heat are expected to increase with climate change (Huang et

Extreme hot-weather events have become life-threatening natural phenomena in many cities around the world, and the health impacts of excessive heat are expected to increase with climate change (Huang et al. 2011; Knowlton et al. 2007; Meehl and Tebaldi 2004; Patz 2005). Heat waves will likely have the worst health impacts in urban areas, where large numbers of vulnerable people reside and where local-scale urban heat island effects (UHI) retard and reduce nighttime cooling. This dissertation presents three empirical case studies that were conducted to advance our understanding of human vulnerability to heat in coupled human-natural systems. Using vulnerability theory as a framework, I analyzed how various social and environmental components of a system interact to exacerbate or mitigate heat impacts on human health, with the goal of contributing to the conceptualization of human vulnerability to heat. The studies: 1) compared the relationship between temperature and health outcomes in Chicago and Phoenix; 2) compared a map derived from a theoretical generic index of vulnerability to heat with a map derived from actual heat-related hospitalizations in Phoenix; and 3) used geospatial information on health data at two areal units to identify the hot spots for two heat health outcomes in Phoenix. The results show a 10-degree Celsius difference in the threshold temperatures at which heat-stress calls in Phoenix and Chicago are likely to increase drastically, and that Chicago is likely to be more sensitive to climate change than Phoenix. I also found that heat-vulnerability indices are sensitive to scale, measurement, and context, and that cities will need to incorporate place-based factors to increase the usefulness of vulnerability indices and mapping to decision making. Finally, I found that identification of geographical hot-spot of heat-related illness depends on the type of data used, scale of measurement, and normalization procedures. I recommend using multiple datasets and different approaches to spatial analysis to overcome this limitation and help decision makers develop effective intervention strategies.

Contributors

Agent

Created

Date Created
  • 2013

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Dietary Intake Behaviors of Recreational Mountain Hikers Climbing "A" Mountain in Summer and Fall

Description

More than 200 hikers are rescued annually in the greater Phoenix area. This study

examined the impact of hiking in hot (HOT), dry temperatures versus moderate (MOD)

temperatures on dietary intake behaviors

More than 200 hikers are rescued annually in the greater Phoenix area. This study

examined the impact of hiking in hot (HOT), dry temperatures versus moderate (MOD)

temperatures on dietary intake behaviors as well as markers of heat stress. Twelve

recreational mountain hikers climbed “A” Mountain four consecutive times (4-miles) on

a HOT day (WBGT=31.6 °C) and again on a MOD day (WBGT= 19.0 °C). Simulated

food and fluid behavior allowed participants to bring what they normally would for a 4-

mile hike and to consume both ad libitum. The following heat stress indicators (mean

difference; p-value), were all significantly higher on the HOT hike compared to the MOD

hike: average core temperature (0.6 °C; p=0.002), average rating of perceived exertion

(2.6; p=0.005), sweat rate (0.54; p=0.01), and fluid consumption (753; p<0.001). On the

HOT hike, 42% of the participants brought enough fluids to meet their individual

calculated fluid needs, however less than 20% actually consumed enough to meet those

needs. On the MOD hike, 56% of participants brought enough fluids to meet their needs,

but only 33% actually consumed enough to meet them. Morning-after USG samples

≥1.020 indicating dehydration on an individual level showed 75% of hikers after the

HOT hike and 67% after the MOD hike were unable to compensate for fluids lost during

the previous day’s hike. Furthermore, participant food intake was low with only three

hikers consuming food on the hot hike, an average of 33.2g of food. No food was

consumed on the MOD hike. These results demonstrate that hikers did not consume

enough fluids to meet their needs while hiking, especially in the heat. They also show

heat stress negatively affected hiker’s physiological and performance measures. Future

recommendations should address food and fluid consumption while hiking in the heat.

Contributors

Agent

Created

Date Created
  • 2020

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Exploring the relationship between design and outdoor thermal comfort in hot and dry climate

Description

Moderate physical activity, such as walking and biking, positively affects physical and mental health. Outdoor thermal comfort is an important prerequisite for incentivizing an active lifestyle. Thus, extreme heat poses

Moderate physical activity, such as walking and biking, positively affects physical and mental health. Outdoor thermal comfort is an important prerequisite for incentivizing an active lifestyle. Thus, extreme heat poses significant challenges for people who are outdoors by choice or necessity. The type and qualities of built infrastructure determine the intensity and duration of individual exposure to heat. As cities globally are shifting priorities towards non-motorized and public transit travel, more residents are expected to experience the city on their feet. Thus, physical conditions as well as psychological perception of the environment that affect thermal comfort will become paramount. Phoenix, Arizona, is used as a case study to examine the effectiveness of current public transit and street infrastructure to reduce heat exposure and affect the thermal comfort of walkers and public transit users.

The City of Phoenix has committed to public transit improvements in the Transportation 2050 plan and has recently adopted a Complete Streets Policy. Proposed changes include mobility improvements and creating a safe and comfortable environment for non-motorized road participants. To understand what kind of improvements would benefit thermal comfort the most, it is necessary to understand heat exposure at finer spatial scales, explore whether current bus shelter designs are adequate in mitigating heat-health effects, and comprehensively assess the impact of design on physical, psychological and behavioral aspects of thermal comfort. A study conducted at bus stops in one Phoenix neighborhood examined grey and green infrastructure types preferred for cooling and found relationships between perception of pleasantness and thermal sensation votes. Walking interviews conducted in another neighborhood event examined the applicability of a framework for walking behavior under the stress of heat, and how differences between the streets affected perceptions of the walkers. The interviews revealed that many of the structural themes from the framework of walking behavior were applicable, however, participants assessed the majority of the elements in their walk from a heat mitigation perspective. Finally, guiding questions for walkability in hot and arid climates were developed based on the literature review and results from the empirical studies. This dissertation contributes to filling the gap between walkability and outdoor thermal comfort, and presents methodology and findings that can be useful to address walkability and outdoor thermal comfort in the world’s hot cities as well as those in temperate climates that may face similar climate challenges in the future as the planet warms.

Contributors

Agent

Created

Date Created
  • 2019

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Climate as a moderator of the effect of disease threat on interpersonal behavior

Description

Infectious diseases have been a major threat to survival throughout human history. Humans have developed a behavioral immune system to prevent infection by causing individuals to avoid people, food, and

Infectious diseases have been a major threat to survival throughout human history. Humans have developed a behavioral immune system to prevent infection by causing individuals to avoid people, food, and objects that could be contaminated. This current project investigates how ambient temperature affects the activation of this system. Because temperature is positively correlated with the prevalence of many deadly diseases, I predict that temperature moderates the behavioral immune system, such that a disease prime will have a stronger effect in a hot environment compared to a neutral environment and one's avoidant behaviors will be more extreme. Participants were placed in a hot room (M = 85F) or a neutral room (M = 77F) and shown a disease prime slide show or a neutral slide show. Disgust sensitivity and perceived vulnerability surveys were used to measure an increased perceived risk to disease. A taste test between a disgusting food item (gummy bugs) and a neutral food item (gummy animals) measured food avoidance. There was no significant avoidance of the gummy and no significant difference in ratings of disgust sensitivity or perceived vulnerability as a function of temperature conditions. There were no significant interactions between temperature and disease. The conclusion is that this study did not provide evidence that temperature moderates the effect of disease cues on behavior.

Contributors

Agent

Created

Date Created
  • 2012

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Heat-related morbidity and thermal comfort: a comparison study of Phoenix and Chicago

Description

I present the results of studies from two historically separate fields of research: heat related illness and human thermal comfort adaptation. My research objectives were: (a) to analyze the relationships

I present the results of studies from two historically separate fields of research: heat related illness and human thermal comfort adaptation. My research objectives were: (a) to analyze the relationships between climate and heat related morbidity in Phoenix, Arizona and Chicago, Illinois; (b) explore possible linkages of human thermal comfort adaptation to heat-related illness; and (c) show possible benefits of collaboration between the two fields of research. Previous climate and mortality studies discovered regional patterns in summertime mortality in North America: lower in hot, southern cities compared to more temperate cities. I examined heat related emergency (911) dispatches from these two geographically and climatically different cities. I analyzed with local weather conditions with 911 dispatches identified by responders as "heat" related from 2001 to 2006 in Phoenix and 2003 through 2006 in Chicago. Both cities experienced a rapid rise in heat-related dispatches with increasing temperature and heat index, but at higher thresholds in Phoenix. Overall, Phoenix had almost two and half times more heat-related dispatches than Chicago. However, Phoenix did not experience the large spikes of heat-related dispatches that occurred in Chicago. These findings suggest a resilience to heat-related illness that may be linked to acclimatization in Phoenix. I also present results from a survey based outdoor human thermal comfort field study in Phoenix to assess levels of local acclimatization. Previous research in outdoor human thermal comfort in hot humid and temperate climates used similar survey-based methodologies and found higher levels of thermal comfort (adaptation to heat) that in warmer climates than in cooler climates. The study presented in this dissertation found outdoor thermal comfort thresholds and heat tolerance levels in Phoenix were higher than previous studies from temperate climates more similar to Chicago. These differences were then compared to the differences in weather conditions associated with heat-related dispatches. The higher comfort thresholds in Phoenix were similar in scale to the climate differences associated with the upsurge in heat-related dispatches in Phoenix and Chicago. This suggests a link between heat related illness and acclimatization, and illustrates potential for collaboration in research between the two fields.

Contributors

Agent

Created

Date Created
  • 2012

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Menopause Symptoms in Underserved and Homeless Women living in the Extreme Temperatures of Arizona

Description

Regional and geographical differences may explain variability in menopausal symptom occurrence due to development of climate-specific thermoneutral zones leading to population-specific hot flash frequencies. Limited information available regarding menopausal symptoms

Regional and geographical differences may explain variability in menopausal symptom occurrence due to development of climate-specific thermoneutral zones leading to population-specific hot flash frequencies. Limited information available regarding menopausal symptoms in underserved women living in extreme heat.

Understanding the perception of menopausal symptoms in underserved women living in extreme heat regions to identify if heat impacts perception of menopausal symptoms was the objective of this study. Women in free, low-income, and homeless clinics in Phoenix were surveyed during summer and winter months using a self-administered, written questionnaire including demographic, climate and menopause related questions, including the Green Climacteric Scale (GCS).

A total of 139 predominantly Hispanic (56 %), uninsured (53 %), menopausal (56 %), mid-aged (mean 49.9, SD 10.3) women were surveyed— 36% were homeless or in shelters. Most women were not on menopausal hormone therapy (98 %). Twenty-two percent reported hot flashes and 26% night sweats. Twenty-five percent of women reported previously becoming ill from heat. More women thought season influenced menopausal symptoms during summer than winter (41 % vs. 14 %, p = 0.0009). However, majority of women did not think temperature outside influenced their menopausal symptoms and that did not differ by season (73 % in winter vs. 60% in summer, p=0.1094). No statistically significant differences seen for vasomotor symptoms between winter and summer months.

Regional and geographical differences may be key in understanding the variability in menopausal symptoms. Regardless of season, the menopausal, underserved and homeless women living in Arizona reported few vasomotor symptoms. In the summer, they were more likely to report that the season influenced their menopausal symptoms rather than temperature suggesting an influence of the season on symptom perception.

Contributors

Agent

Created

Date Created
  • 2018-05

Walking and Transit and Heat, Oh My!: An Exposure Study of Phoenix Pedestrians

Description

Many people use public transportation in their daily lives, which is often praised at as a healthy and sustainable choice to make. However, in extreme temperatures this also puts people

Many people use public transportation in their daily lives, which is often praised at as a healthy and sustainable choice to make. However, in extreme temperatures this also puts people at a greater risk for negative consequences resulting from such exposure to heat. In Phoenix, public transportation riders are faced with extreme heat in the summer along with the increased internal heat production caused by the physical activity required to use public transportation. In this study, I estimated total exposure and average exposure per rider for six stops in Phoenix. To do this I used City of Phoenix ridership data, weather data, and survey responses from an ASU City of Phoenix Bus Stop Survey conducted in summer 2016. These data sets were combined by multiplying different metrics to produce various exposure values. During analysis two sets of calculations were made. One keeping weather constant and another keeping ridership constant. I found that there was a large range of exposure between the selected stops and that the thermal environment influences the amount of exposure depending on the time of day the exposure is occurring. During the morning a greener location leads to less exposure, while in the afternoon an urban location leads to less exposure. Know detailed information about exposure at these stops I was also able to evaluate survey participants' thermal comfort at each stop and how it may relate to exposure. These findings are useful in making educated transportation planning decisions and improving the quality of life for people living in places with extreme summer temperatures.

Contributors

Created

Date Created
  • 2018-05