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A well-insulated dark conventional rooftop can be hotter than any other urban surface, including pavements. Since rooftops cover around 20 – 25% of most urban areas, their role in the urban heat island effect is significant. In general, buildings exchange heat with the surroundings in three ways: heat release from

A well-insulated dark conventional rooftop can be hotter than any other urban surface, including pavements. Since rooftops cover around 20 – 25% of most urban areas, their role in the urban heat island effect is significant. In general, buildings exchange heat with the surroundings in three ways: heat release from the cooling/heating system, air exchange associated with exfiltration and relief air, and heat transfer between the building envelope and surroundings. Several recent studies show that the building envelope generates more heat release into the environment than any other building component.Current advancements in material science have enabled the development of materials and coatings with very high solar reflectance and thermal emissivity, and that can alter their radiative properties based on surface temperature. This dissertation is an effort to quantify the impact of recent developments in such technologies on urban air. The current study addresses three specific unresolved topics: 1) the relative importance of rooftop solar reflectance and thermal emissivity, 2) the role of rooftop radiative properties in different climates, and 3) the impact of temperature-adaptive exterior materials/coatings on building energy savings and urban cooling. The findings from this study show that the use of rooftop materials with solar reflectance above 0.9 maintain the surface temperature below ambient air temperature most of the time, even when the materials have conventional thermal emissivity (0.9). This research has demonstrated that for hot cities, rooftops with high solar reflectance and thermal emittance maximize building energy savings and always cool the surrounding air. For moderate climate regions, high solar reflectance and low thermal emittance result in the greatest building energy cost savings. This combination of radiative properties cools the air during the daytime and warms it at night. Finally, this research found that temperature-adaptive materials could play a significant role in reducing utility costs for poorly insulated buildings, but that they heat the surrounding air in the winter, irrespective of the rooftop insulation. Through the detailed analysis of building façade radiative properties, this dissertation offers climate-specific design guidance that can be used to simultaneously optimize energy costs while minimizing adverse warming of the surrounding environment.
ContributorsPrem Anand Jayaprabha, Jyothis Anand (Author) / Sailor, David (Thesis advisor) / Phelan, Patrick (Thesis advisor) / Huang, Huei-Ping (Committee member) / Wang, Liping (Committee member) / Yeom, Dongwoo Jason (Committee member) / Arizona State University (Publisher)
Created2022
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Description
Inequities and exclusions, compounded by the increasing intensity of extreme weather events, pose significant challenges to urban planning for low-elevation coastal zones (LECZ). Inclusive development (ID) and urban flood resilience (UFR) have emerged as widely endorsed solutions by scholars. Granting that they gain substantial support and enthusiasm, they have the

Inequities and exclusions, compounded by the increasing intensity of extreme weather events, pose significant challenges to urban planning for low-elevation coastal zones (LECZ). Inclusive development (ID) and urban flood resilience (UFR) have emerged as widely endorsed solutions by scholars. Granting that they gain substantial support and enthusiasm, they have the potential to transform vulnerable urban areas. While their noble intentions are commendable, the intricacies of ID cannot be overlooked, as UFR often inherits and perpetuates the inequalities ingrained in conventional development paradigms. Given the critical importance of ID and UFR in contemporary urban planning, my dissertation research devolved into their fusion by answering my main research question, what constitutes inclusive urban flood resilience? This investigation was carried out through a series of four secondary research questions distributed over three academic papers, each contributing a unique perspective and insights to this burgeoning field. Through a systematic literature review and employing bibliometric and thematic analyses, Chapter 2 offers a comprehensive understanding of inclusive development and a refined definition of the concept. Subsequently, taking Georgetown, the capital city of Guyana, as a case study, Chapter 3 estimates its UFR and employs dimensionality reduction by way of principal component analysis to present these findings in a transparent manner. Chapter 4 builds on the findings of the previous chapters, by first presenting a novel approach to evaluate inclusive development within the framework of the results of Chapter 2, and secondly, together with a systematic meta-analysis of flood resilience measurements, it offers an examination of the ID-UFR nexus. The findings suggest that the concept of inclusive development is nuanced by context-specific definitions, that flood resilience in Georgetown varies among its sub-districts, and that city dimensions (natural, built, social, economic, and institutional), as assessed by pooling global studies, do not share synergistic relationships, being a measure of inclusive development. These findings are critical to urban planning in Georgetown and similar contexts globally as they provide data-driven guidance for understanding these concepts and applying them toward developing inclusive and flood-resilient cities and communities.
ContributorsRenville, Dwayne (Author) / Cheng, Chingwen (Thesis advisor) / Vogel, Kathleen (Thesis advisor) / Chhetri, Netra (Committee member) / Zeng, Ruijie (Committee member) / Arizona State University (Publisher)
Created2023
Description

There are unfortunately very few curricular guides that focus on community engagement within the higher education of landscape architecture. A Beginner’s Guide to Community Engagement in the Curriculum of Landscape Architecture and Urban Planning to Improve Social Justice and Sustainability helps resolve this issue and serves as a resource to

There are unfortunately very few curricular guides that focus on community engagement within the higher education of landscape architecture. A Beginner’s Guide to Community Engagement in the Curriculum of Landscape Architecture and Urban Planning to Improve Social Justice and Sustainability helps resolve this issue and serves as a resource to students, educators, designers, and more. The guide centralizes a diverse collection of resources, guides students through learning materials, shares insight, and proposes potential community engagement methods. The booklet aims to help readers understand the importance of community engagement in design and shares different curricular approaches to introduce the work to students.

ContributorsNeeson, Margaret (Author) / Cheng, Chingwen (Thesis director) / Coseo, Paul (Committee member) / Barrett, The Honors College (Contributor) / School of Sustainability (Contributor) / School of Geographical Sciences and Urban Planning (Contributor) / The Design School (Contributor)
Created2023-05
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Description
Urban-induced heating is a challenge to the livability and health of city dwellers. It is a complex issue that many cities are facing, and a more urgent hazard in hot urban deserts (HUDs) than elsewhere due to already high temperatures and aridity. The challenge compounds in the absence of more

Urban-induced heating is a challenge to the livability and health of city dwellers. It is a complex issue that many cities are facing, and a more urgent hazard in hot urban deserts (HUDs) than elsewhere due to already high temperatures and aridity. The challenge compounds in the absence of more localized heat mitigation understanding. In addition, over-reliance on evidence from temperate regions is disconnected from the actualities of extreme bioclimatic dynamics found in HUDs. This dissertation is an integration of a series of studies that inform urban climate relationships specific to HUDs. This three-paper dissertation demonstrates heat mitigation aspirational goals from actualities, depicts local urban thermal drivers in Kuwait, and then tests morphological sensitivity of selected thermal modulation strategies in one neighborhood in Kuwait City.

The first paper is based on a systematic literature review where evidence from morphological mitigation strategies in HUDs were critically reviewed, synthesized and integrated. Metrics, measurements, and methods were extracted to examine the applicability of the different strategies, and a content synthesis identified the levels of strategy success. Collective challenges and uncertainties were interpreted to compare aspirational goals from actualities of morphological mitigation strategies.

The second paper unpacks the relationship of urban morphological attributes in influencing thermal conditions to assess latent magnitudes of heat amelioration strategies. Mindful of the challenges presented in the first study, a 92-day summer field-measurement campaign captured system dynamics of urban thermal stimuli within sub-diurnal phenomena. A composite data set of sub-hourly air temperature measurements with sub-meter morphological attributes was built, statistically analyzed, and modeled. Morphological mediation effects were found to vary hourly with different patterns under varying weather conditions in non-linear associations. Results suggest mitigation interventions be investigated and later tested on a site- use and time-use basis.

The third paper concludes with a simulation-based study to conform on the collective findings of the earlier studies. The microclimate model ENVI-met 4.4, combined with field measurements, was used to simulate the effect of rooftop shade-sails in cooling the near ground thermal environment. Results showed significant cooling effects and thus presented a novel shading approach that challenges orthodox mitigation strategies in HUDs.
ContributorsAlKhaled, Saud R A H (Author) / Coseo, Paul (Thesis advisor) / Brazel, Anthony (Thesis advisor) / Middel, Ariane (Committee member) / Cheng, Chingwen (Committee member) / Arizona State University (Publisher)
Created2019
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Description

Environmental heat is a growing concern in cities as a consequence of rapid urbanization and climate change, threatening human health and urban vitality. The transportation system is naturally embedded in the issue of urban heat and human heat exposure. Research has established how heat poses a threat to urban inhabitants

Environmental heat is a growing concern in cities as a consequence of rapid urbanization and climate change, threatening human health and urban vitality. The transportation system is naturally embedded in the issue of urban heat and human heat exposure. Research has established how heat poses a threat to urban inhabitants and how urban infrastructure design can lead to increased urban heat. Yet there are gaps in understanding how urban communities accumulate heat exposure, and how significantly the urban transportation system influences or exacerbates the many issues of urban heat. This dissertation focuses on advancing the understanding of how modern urban transportation influences urban heat and human heat exposure through three research objectives: 1) Investigate how human activity results in different outdoor heat exposure; 2) Quantify the growth and extent of urban parking infrastructure; and 3) Model and analyze how pavements and vehicles contribute to urban heat.

In the urban US, traveling outdoors (e.g. biking or walking) is the most frequent activity to cause heat exposure during hot periods. However, outdoor travel durations are often very short, and other longer activities such as outdoor housework and recreation contribute more to cumulative urban heat exposure. In Phoenix, parking and roadway pavement infrastructure contributes significantly to the urban heat balance, especially during summer afternoons, and vehicles only contribute significantly in local areas with high density rush hour vehicle travel. Future development of urban areas (especially those with concerns of extreme heat) should focus on ensuring access and mobility for its inhabitants without sacrificing thermal comfort. This may require urban redesign of transportation systems to be less auto-centric, but without clear pathways to mitigating impacts of urban heat, it may be difficult to promote transitions to travel modes that inherently necessitate heat exposure. Transportation planners and engineers need to be cognizant of the pathways to increased urban heat and human heat exposure when planning and designing urban transportation systems.

ContributorsHoehne, Christopher Glenn (Author) / Chester, Mikhail V (Thesis advisor) / Hondula, David M. (Committee member) / Sailor, David (Committee member) / Pendyala, Ram M. (Committee member) / Arizona State University (Publisher)
Created2019
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Description
Rapid urban expansion and the associated landscape modifications have led to significant changes of surface processes in built environments. These changes further interact with the overlying atmospheric boundary layer and strongly modulate urban microclimate. To capture the impacts of urban land surface processes on urban boundary layer dynamics, a coupled

Rapid urban expansion and the associated landscape modifications have led to significant changes of surface processes in built environments. These changes further interact with the overlying atmospheric boundary layer and strongly modulate urban microclimate. To capture the impacts of urban land surface processes on urban boundary layer dynamics, a coupled urban land-atmospheric modeling framework has been developed. The urban land surface is parameterized by an advanced single-layer urban canopy model (SLUCM) with realistic representations of urban green infrastructures such as lawn, tree, and green roof, etc. The urban atmospheric boundary layer is simulated by a single column model (SCM) with both convective and stable schemes. This coupled SLUCM-SCM framework can simulate the time evolution and vertical profile of different meteorological variables such as virtual potential temperature, specific humidity and carbon dioxide concentration. The coupled framework has been calibrated and validated in the metropolitan Phoenix area, Arizona. To quantify the model sensitivity, an advanced stochastic approach based on Markov-Chain Monte Carlo procedure has been applied. It is found that the development of urban boundary layer is highly sensitive to surface characteristics of built terrains, including urban land use, geometry, roughness of momentum, and vegetation fraction. In particular, different types of urban vegetation (mesic/xeric) affect the boundary layer dynamics through different mechanisms. Furthermore, this framework can be implanted into large-scale models such as Weather Research and Forecasting model to assess the impact of urbanization on regional climate.
ContributorsSong, Jiyun (Author) / Wang, Zhihua (Thesis advisor) / Vivoni, Enrique R (Committee member) / Mascaro, Giuseppe (Committee member) / Myint, Soe W (Committee member) / Sailor, David (Committee member) / Arizona State University (Publisher)
Created2016
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Description
This dissertation focuses on thermal comfort and walking as an experiential phenomenon in outdoor urban environments. The goal of the study is to provide a better understanding of the impact of psychological adaptation factors on thermal comfort. The main research questions included the impact of psychological factors on outdoor thermal

This dissertation focuses on thermal comfort and walking as an experiential phenomenon in outdoor urban environments. The goal of the study is to provide a better understanding of the impact of psychological adaptation factors on thermal comfort. The main research questions included the impact of psychological factors on outdoor thermal comfort as well as the impact of long-term thermal perception on momentary thermal sensation. My research follows a concurrent triangulation strategy as a mixed-method approach, which consisted of a simultaneous collection and analysis of qualitative and quantitative data. Research consisted of five rounds of data collection in different locations beginning February 2018 and continuing through December 2019. During the qualitative phase, I gathered data in the form of an open-ended questionnaire but importantly, self-walking interviews where participants narrated their experience of the environment while recording one-minute long videos. The visual and audible information was first processed using thematic analysis and then further analyzed via Latent Dirichlet Allocation (LDA). During the quantitative phase, I gathered information from participants in the form of three-step survey questionnaires, that data was analyzed using T-Test regression analysis in STATA. The quantitative data helped explore and address the initial research questions, while the qualitative data helped in addressing and explaining the trends and the experiential aspects of thermal environment.

Results revealed that spatial familiarity (as a psychological adaptation factor) has a significant relationship for both overall comfort and thermal comfort within outdoor environments. Moreover, long term thermal memory influences momentary thermal sensation. The results of qualitative and quantitative data were combined, compared, and contrasted to generate new insights in the design of outdoor urban environments. The depth and breadth of the qualitative data set consisting of more than a thousand minute-long of narrated video segments along with hundreds of pages of transcribed text, demonstrated the subjective aspects of thermal comfort. This research highlights the importance of context-based and human-centric design in any evidence-based design approach for outdoor environments. The implications of the study can provide new insights not only for architects and urban designers, but also for city planners, stakeholders, public officials, and policymakers.
ContributorsGarshasby Moakhar, Mohsen (Author) / Hejduk, Renata (Thesis advisor) / Cheng, Chingwen (Committee member) / Coseo, Paul (Committee member) / Margolis, Eric (Committee member) / Arizona State University (Publisher)
Created2020
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Description

Communicating climate risks is crucial when engaging the public to support climate action planning and addressing climate justice. How does evidence-based communication influence local residents’ risk perception and potential behavior change in support of climate planning? Built upon our previous study of Climate Justice maps illustrating high scores of both

Communicating climate risks is crucial when engaging the public to support climate action planning and addressing climate justice. How does evidence-based communication influence local residents’ risk perception and potential behavior change in support of climate planning? Built upon our previous study of Climate Justice maps illustrating high scores of both social and ecological vulnerability in Michigan’s Huron River watershed, USA, a quasi-experiment was conducted to examine the effects of Climate Justice mapping intervention on residents’ perceptions and preparedness for climate change associated hazards in Michigan. Two groups were compared: residents in Climate Justice areas with high social and ecological vulnerability scores in the watershed (n=76) and residents in comparison areas in Michigan (n=69). Measurements for risk perception include perceived exposure, sensitivity, and adaptability to hazards. Results indicate that risk information has a significant effect on perceived sensitivity and level of preparedness for future climate extremes among participants living in Climate Justice areas. Findings highlight the value of integrating scientific risk assessment information in risk communication to align calculated and perceived risks. This study suggests effective risk communication can influence local support of climate action plans and implementation of strategies that address climate justice and achieve social sustainability in local communities.

ContributorsCheng, Chingwen (Author) / Tsai, Jiun-Yi (Author) / Yang, Y. C. Ethan (Author) / Esselman, Rebecca (Author) / Kalcic, Margaret (Author) / Xu, Xin (Author) / Mohai, Paul (Author) / Herberger Institute for Design and the Arts (Contributor)
Created2017-10-12
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Description

We use the Northeast US Urban Climate Archipelago as a case study to explore three key limitations of planning and policy initiatives to mitigate extreme urban heat. These limitations are: (1) a lack of understanding of spatial considerations—for example, how nearby urban areas interact, affecting, and being affected by, implementation

We use the Northeast US Urban Climate Archipelago as a case study to explore three key limitations of planning and policy initiatives to mitigate extreme urban heat. These limitations are: (1) a lack of understanding of spatial considerations—for example, how nearby urban areas interact, affecting, and being affected by, implementation of such policies; (2) an emphasis on air temperature reduction that neglects assessments of other important meteorological parameters, such as humidity, mixing heights, and urban wind fields; and (3) too narrow of a temporal focus—either time of day, season, or current vs. future climates. Additionally, the absence of a direct policy/planning linkage between heat mitigation goals and actual human health outcomes, in general, leads to solutions that only indirectly address the underlying problems. These issues are explored through several related atmospheric modeling case studies that reveal the complexities of designing effective urban heat mitigation strategies. We conclude with recommendations regarding how policy-makers can optimize the performance of their urban heat mitigation policies and programs. This optimization starts with a thorough understanding of the actual end-point goals of these policies, and concludes with the careful integration of scientific knowledge into the development of location-specific strategies that recognize and address the limitations discussed herein.

ContributorsSailor, David (Author) / Shepherd, Marshall (Author) / Sheridan, Scott (Author) / Stone, Brian (Author) / Laurence, Kalkstein (Author) / Russell, Armistead (Author) / Vargo, Jason (Author) / Andersen, Theresa (Author)
Created2016-10-12
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A web-based software tool has been developed to assist urban planners and air quality management officials in assessing the potential ofurban heat island mitigation strategies to affect the urban climate, air quality, and energy consumption within their cities. The user of thetool can select from over 170 US cities for

A web-based software tool has been developed to assist urban planners and air quality management officials in assessing the potential ofurban heat island mitigation strategies to affect the urban climate, air quality, and energy consumption within their cities. The user of thetool can select from over 170 US cities for which to conduct the analysis, and can specify city-wide changes in surface reflectivity and/or veg-etative cover. The Mitigation Impact Screening Tool (MIST) then extrapolates results from a suite of simulations for 20 cities to estimate airtemperature changes associated with the specified changes in surface characteristics for the selected city. Alternatively the user can simply definea nominal air temperature reduction that they hope to achieve with an unspecified mitigation scenario. These air temperature changes are theninput to energy and ozone models to estimate the impact that the mitigation action may have on the selected city. The results presented by MISTinclude a high degree of uncertainty and are intended only as a first-order estimate that urban planners can use to assess the viability of heatisland mitigation strategies for their cities. As appropriate, MIST analyses should be supplemented by more detailed modeling.

ContributorsSailor, David (Author) / Deitsch, Nikolaas (Author)
Created2007-02-05