Matching Items (13)
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Description
This doctoral thesis investigates the predictability characteristics of floods and flash floods by coupling high resolution precipitation products to a distributed hydrologic model. The research hypotheses are tested at multiple watersheds in the Colorado Front Range (CFR) undergoing warm-season precipitation. Rainfall error structures are expected to propagate into hydrologic simulations

This doctoral thesis investigates the predictability characteristics of floods and flash floods by coupling high resolution precipitation products to a distributed hydrologic model. The research hypotheses are tested at multiple watersheds in the Colorado Front Range (CFR) undergoing warm-season precipitation. Rainfall error structures are expected to propagate into hydrologic simulations with added uncertainties by model parameters and initial conditions. Specifically, the following science questions are addressed: (1) What is the utility of Quantitative Precipitation Estimates (QPE) for high resolution hydrologic forecasts in mountain watersheds of the CFR?, (2) How does the rainfall-reflectivity relation determine the magnitude of errors when radar observations are used for flood forecasts?, and (3) What are the spatiotemporal limits of flood forecasting in mountain basins when radar nowcasts are used into a distributed hydrological model?. The methodology consists of QPE evaluations at the site (i.e., rain gauge location), basin-average and regional scales, and Quantitative Precipitation Forecasts (QPF) assessment through regional grid-to-grid verification techniques and ensemble basin-averaged time series. The corresponding hydrologic responses that include outlet discharges, distributed runoff maps, and streamflow time series at internal channel locations, are used in light of observed and/or reference data to diagnose the suitability of fusing precipitation forecasts into a distributed model operating at multiple catchments. Results reveal that radar and multisensor QPEs lead to an improved hydrologic performance compared to simulations driven with rain gauge data only. In addition, hydrologic performances attained by satellite products preserve the fundamental properties of basin responses, including a simple scaling relation between the relative spatial variability of runoff and its magnitude. Overall, the spatial variations contained in gridded QPEs add value for warm-season flood forecasting in mountain basins, with sparse data even if those products contain some biases. These results are encouraging and open new avenues for forecasting in regions with limited access and sparse observations. Regional comparisons of different reflectivity -rainfall (Z-R) relations during three summer seasons, illustrated significant rainfall variability across the region. Consistently, hydrologic errors introduced by the distinct Z-R relations, are significant and proportional (in the log-log space) to errors in precipitation estimations and stream flow magnitude. The use of operational Z-R relations without prior calibration may lead to wrong estimation of precipitation, runoff magnitude and increased flood forecasting errors. This suggests that site-specific Z-R relations, prior to forecasting procedures, are desirable in complex terrain regions. Nowcasting experiments show the limits of flood forecasting and its dependence functions of lead time and basin scale. Across the majority of the basins, flood forecasting skill decays with lead time, but the functional relation depends on the interactions between watershed properties and rainfall characteristics. Both precipitation and flood forecasting skills are noticeably reduced for lead times greater than 30 minutes. Scale dependence of hydrologic forecasting errors demonstrates reduced predictability at intermediate-size basins, the typical scale of convective storm systems. Overall, the fusion of high resolution radar nowcasts and the convenient parallel capabilities of the distributed hydrologic model provide an efficient framework for generating accurate real-time flood forecasts suitable for operational environments.
ContributorsMoreno Ramirez, Hernan (Author) / Vivoni, Enrique R. (Thesis advisor) / Ruddell, Benjamin L. (Committee member) / Gochis, David J. (Committee member) / Mays, Larry W. (Committee member) / Huang, Huei-Ping (Committee member) / Arizona State University (Publisher)
Created2012
Description

Public transit systems are often accepted as energy and environmental improvements to automobile travel, however, few life cycle assessments exist to understand the effects of implementation of transit policy decisions. To better inform decision-makers, this project evaluates the decision to construct and operate public transportation systems and the expected energy

Public transit systems are often accepted as energy and environmental improvements to automobile travel, however, few life cycle assessments exist to understand the effects of implementation of transit policy decisions. To better inform decision-makers, this project evaluates the decision to construct and operate public transportation systems and the expected energy and environmental benefits over continued automobile use. The public transit systems are selected based on screening criteria. Initial screening included advanced implementation (5 to 10 years so change in ridership could be observed), similar geographic regions to ensure consistency of analysis parameters, common transit agencies or authorities to ensure a consistent management culture, and modes reflecting large infrastructure investments to provide an opportunity for robust life cycle assessment of large impact components. An in-depth screening process including consideration of data availability, project age, energy consumption, infrastructure information, access and egress information, and socio-demographic characteristics was used as the second filter. The results of this selection process led to Los Angeles Metro’s Orange and Gold lines.

In this study, the life cycle assessment framework is used to evaluate energy inputs and emissions of greenhouse gases, particulate matter (10 and 2.5 microns), sulfur dioxide, nitrogen oxides, volatile organic compounds, and carbon monoxide. For the Orange line, Gold line, and competing automobile trip, an analysis system boundary that includes vehicle, infrastructure, and energy production components is specified. Life cycle energy use and emissions inventories are developed for each mode considering direct (vehicle operation), ancillary (non-vehicle operation including vehicle maintenance, infrastructure construction, infrastructure operation, etc.), and supply chain processes and services. In addition to greenhouse gas emissions, the inventories are linked to their potential for respiratory impacts and smog formation, and the time it takes to payback in the lifetime of each transit system.

Results show that for energy use and greenhouse gas emissions, the inclusion of life cycle components increases the footprint between 42% and 91% from vehicle propulsion exclusively. Conventional air emissions show much more dramatic increases highlighting the effectiveness of “tailpipe” environmental policy. Within the life cycle, vehicle operation is often small compared to other components. Particulate matter emissions increase between 270% and 5400%. Sulfur dioxide emissions increase by several orders of magnitude for the on road modes due to electricity use throughout the life cycle. NOx emissions increase between 31% and 760% due to supply chain truck and rail transport. VOC emissions increase due to infrastructure material production and placement by 420% and 1500%. CO emissions increase by between 20% and 320%. The dominating contributions from life cycle components show that the decision to build an infrastructure and operate a transportation mode in Los Angeles has impacts far outside of the city and region. Life cycle results are initially compared at each system’s average occupancy and a breakeven analysis is performed to compare the range at which modes are energy and environmentally competitive.

The results show that including a broad suite of energy and environmental indicators produces potential tradeoffs that are critical to decision makers. While the Orange and Gold line require less energy and produce fewer greenhouse gas emissions per passenger mile traveled than the automobile, this ordering is not necessarily the case for the conventional air emissions. It is possible that a policy that focuses on one pollutant may increase another, highlighting the need for a broad set of indicators and life cycle thinking when making transportation infrastructure decisions.

Description

Public transportation systems are often part of strategies to reduce urban environmental impacts from passenger transportation, yet comprehensive energy and environmental life-cycle measures, including upfront infrastructure effects and indirect and supply chain processes, are rarely considered. Using the new bus rapid transit and light rail lines in Los Angeles, near-term

Public transportation systems are often part of strategies to reduce urban environmental impacts from passenger transportation, yet comprehensive energy and environmental life-cycle measures, including upfront infrastructure effects and indirect and supply chain processes, are rarely considered. Using the new bus rapid transit and light rail lines in Los Angeles, near-term and long-term life-cycle impact assessments are developed, including consideration of reduced automobile travel. Energy consumption and emissions of greenhouse gases and criteria pollutants are assessed, as well the potential for smog and respiratory impacts.

Results show that life-cycle infrastructure, vehicle, and energy production components significantly increase the footprint of each mode (by 48–100% for energy and greenhouse gases, and up to 6200% for environmental impacts), and emerging technologies and renewable electricity standards will significantly reduce impacts. Life-cycle results are identified as either local (in Los Angeles) or remote, and show how the decision to build and operate a transit system in a city produces environmental impacts far outside of geopolitical boundaries. Ensuring shifts of between 20–30% of transit riders from automobiles will result in passenger transportation greenhouse gas reductions for the city, and the larger the shift, the quicker the payback, which should be considered for time-specific environmental goals.

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Description

In this study we characterized the relationship between temperature and mortality in central Arizona desert cities that have an extremely hot climate. Relationships between daily maximum apparent temperature (ATmax) and mortality for eight condition-specific causes and all-cause deaths were modeled for all residents and separately for males and females ages

In this study we characterized the relationship between temperature and mortality in central Arizona desert cities that have an extremely hot climate. Relationships between daily maximum apparent temperature (ATmax) and mortality for eight condition-specific causes and all-cause deaths were modeled for all residents and separately for males and females ages <65 and ≥65 during the months May–October for years 2000–2008. The most robust relationship was between ATmax on day of death and mortality from direct exposure to high environmental heat. For this condition-specific cause of death, the heat thresholds in all gender and age groups (ATmax = 90–97 °F; 32.2‒36.1 °C) were below local median seasonal temperatures in the study period (ATmax = 99.5 °F; 37.5 °C). Heat threshold was defined as ATmax at which the mortality ratio begins an exponential upward trend. Thresholds were identified in younger and older females for cardiac disease/stroke mortality (ATmax = 106 and 108 °F; 41.1 and 42.2 °C) with a one-day lag. Thresholds were also identified for mortality from respiratory diseases in older people (ATmax = 109 °F; 42.8 °C) and for all-cause mortality in females (ATmax = 107 °F; 41.7 °C) and males <65 years (ATmax = 102 °F; 38.9 °C). Heat-related mortality in a region that has already made some adaptations to predictable periods of extremely high temperatures suggests that more extensive and targeted heat-adaptation plans for climate change are needed in cities worldwide.

ContributorsHarlan, Sharon L. (Author) / Chowell, Gerardo (Author) / Yang, Shuo (Author) / Petitti, Diana B. (Author) / Morales Butler, Emmanuel J. (Author) / Ruddell, Benjamin L. (Author) / Ruddell, Darren M. (Author)
Created2014-05-20
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Description

In an extreme heat event, people can go to air-conditioned public facilities if residential air-conditioning is not available. Residences that heat slowly may also mitigate health effects, particularly in neighborhoods with social vulnerability. We explored the contributions of social vulnerability and these infrastructures to heat mortality in Maricopa County and

In an extreme heat event, people can go to air-conditioned public facilities if residential air-conditioning is not available. Residences that heat slowly may also mitigate health effects, particularly in neighborhoods with social vulnerability. We explored the contributions of social vulnerability and these infrastructures to heat mortality in Maricopa County and whether these relationships are sensitive to temperature. Using Poisson regression modeling with heat-related mortality as the outcome, we assessed the interaction of increasing temperature with social vulnerability, access to publicly available air conditioned space, home air conditioning and the thermal properties of residences. As temperatures increase, mortality from heat-related illness increases less in census tracts with more publicly accessible cooled spaces. Mortality from all internal causes of death did not have this association. Building thermal protection was not associated with mortality. Social vulnerability was still associated with mortality after adjusting for the infrastructure variables. To reduce heat-related mortality, the use of public cooled spaces might be expanded to target the most vulnerable.

ContributorsEisenman, David P. (Author) / Wilhalme, Holly (Author) / Tseng, Chi-Hong (Author) / Chester, Mikhail Vin (Author) / English, Paul (Author) / Pincetl, Stephanie Sabine, 1952- (Author) / Fraser, Andrew (Author) / Vangala, Sitaram (Author) / Dhaliwal, Satvinder K. (Author)
Created2016-08-03
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Description

Objectives: To provide novel quantification and advanced measurements of surface temperatures (Ts) in playgrounds, employing multiple scales of data, and provide insight into hot-hazard mitigation techniques and designs for improved environmental and public health.

Methods: We conduct an analysis of Ts in two Metro-Phoenix playgrounds at three scales: neighborhood (1 km

Objectives: To provide novel quantification and advanced measurements of surface temperatures (Ts) in playgrounds, employing multiple scales of data, and provide insight into hot-hazard mitigation techniques and designs for improved environmental and public health.

Methods: We conduct an analysis of Ts in two Metro-Phoenix playgrounds at three scales: neighborhood (1 km resolution), microscale (6.8 m resolution), and touch-scale (1 cm resolution). Data were derived from two sources: airborne remote sensing (neighborhood and microscale) and in situ (playground site) infrared Ts (touch-scale). Metrics of surface-to-air temperature deltas (Ts–a) and scale offsets (errors) are introduced.

Results: Select in situ Ts in direct sunlight are shown to approach or surpass values likely to result in burns to children at touch-scales much finer than Ts resolved by airborne remote sensing. Scale offsets based on neighbourhood and microscale ground observations are 3.8 ◦C and 7.3 ◦C less than the Ts–a at the 1 cm touch-scale, respectively, and 6.6 ◦C and 10.1 ◦C lower than touch-scale playground equipment Ts, respectively. Hence, the coarser scales underestimate high Ts within playgrounds. Both natural (tree) and artificial (shade sail) shade types are associated with significant reductions in Ts.

Conclusions: A scale mismatch exists based on differing methods of urban Ts measurement. The sub-meter touch-scale is the spatial scale at which data must be collected and policies of urban landscape design and health must be executed in order to mitigate high Ts in high-contact environments such as playgrounds. Shade implementation is the most promising mitigation technique to reduce child burns, increase park usability, and mitigate urban heating.

ContributorsVanos, Jennifer K. (Author) / Middel, Ariane (Author) / McKercher, Grant R. (Author) / Kuras, Evan R. (Author) / Ruddell, Benjamin L. (Author)
Created2015-11-10
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Description

Preventing heat-associated morbidity and mortality is a public health priority in Maricopa County, Arizona (United States). The objective of this project was to evaluate Maricopa County cooling centers and gain insight into their capacity to provide relief for the public during extreme heat events. During the summer of 2014, 53

Preventing heat-associated morbidity and mortality is a public health priority in Maricopa County, Arizona (United States). The objective of this project was to evaluate Maricopa County cooling centers and gain insight into their capacity to provide relief for the public during extreme heat events. During the summer of 2014, 53 cooling centers were evaluated to assess facility and visitor characteristics. Maricopa County staff collected data by directly observing daily operations and by surveying managers and visitors. The cooling centers in Maricopa County were often housed within community, senior, or religious centers, which offered various services for at least 1500 individuals daily. Many visitors were unemployed and/or homeless. Many learned about a cooling center by word of mouth or by having seen the cooling center’s location. The cooling centers provide a valuable service and reach some of the region’s most vulnerable populations. This project is among the first to systematically evaluate cooling centers from a public health perspective and provides helpful insight to community leaders who are implementing or improving their own network of cooling centers.

ContributorsBerisha, Vjollca (Author) / Hondula, David M. (Author) / Roach, Matthew (Author) / White, Jessica R. (Author) / McKinney, Benita (Author) / Bentz, Darcie (Author) / Mohamed, Ahmed (Author) / Uebelherr, Joshua (Author) / Goodin, Kate (Author)
Created2016-09-23
Description

En la zona metropolitana de Phoenix, el calor urbano está afectando la salud, la seguridad y la economía y se espera que estos impactos empeoren con el tiempo. Se prevé que el número de días por encima de 110˚F aumentará más del doble para el 2060. En mayo de 2017,

En la zona metropolitana de Phoenix, el calor urbano está afectando la salud, la seguridad y la economía y se espera que estos impactos empeoren con el tiempo. Se prevé que el número de días por encima de 110˚F aumentará más del doble para el 2060. En mayo de 2017, The Nature Conservancy, el Departamento de Salud Pública del condado de Maricopa, Central Arizona Conservation Alliance, la Red de Investigación en Sostenibilidad sobre la Resiliencia Urbana a Eventos Extremos, el Centro de Investigación del Clima Urbano de Arizona State University y el Center for Whole Communities lanzaron un proceso participativo de planificación de acciones contra el calor para identificar tanto estrategias de mitigación como de adaptación a fin de reducir directamente el calor y mejorar la capacidad de los residentes para lidiar con el calor. Las organizaciones comunitarias con relaciones existentes en tres vecindarios seleccionados para la planificación de acciones contra el calor se unieron más tarde al equipo del proyecto: Phoenix Revitalization Corporation, RAILMesa y Puente Movement. Más allá de construir un plan de acción comunitario contra el calor y completar proyectos de demostración, este proceso participativo fue diseñado para desarrollar conciencia, iniciativa y cohesión social en las comunidades subrepresentadas. Asimismo el proceso de planificación de acciones contra el calor fue diseñado para servir como modelo para esfuerzos futuros de resiliencia al calor y crear una visión local, contextual y culturalmente apropiada de un futuro más seguro y saludable. El método iterativo de planificación y participación utilizado por el equipo del proyecto fortaleció las relaciones dentro y entre los vecindarios, las organizaciones comunitarias, los responsables de la toma de decisiones y el equipo núcleo, y combinó la sabiduría de la narración de historias y la evidencia científica para comprender mejor los desafíos actuales y futuros que enfrentan los residentes durante eventos de calor extremo. Como resultado de tres talleres en cada comunidad, los residentes presentaron ideas que quieren ver implementadas para aumentar su comodidad y seguridad térmica durante los días de calor extremo.

Como se muestra a continuación, las ideas de los residentes se interceptaron en torno a conceptos similares, pero las soluciones específicas variaron entre los vecindarios. Por ejemplo, a todos los vecindarios les gustaría agregar sombra a sus corredores peatonales, pero variaron las preferencias para la ubicación de las mejoras para dar sombra. Algunos vecindarios priorizaron las rutas de transporte público, otros priorizaron las rutas utilizadas por los niños en su camino a la escuela y otros quieren paradas de descanso con sombra en lugares clave. Surgieron cuatro temas estratégicos generales en los tres vecindarios: promover y educar; mejorar la comodidad/capacidad de afrontamiento; mejorar la seguridad; fortalecer la capacidad. Estos temas señalan que existen serios desafíos de seguridad contra el calor en la vida diaria de los residentes y que la comunidad, los negocios y los sectores responsables de la toma de decisión deben abordar esos desafíos.

Los elementos del plan de acción contra el calor están diseñados para incorporarse a otros esfuerzos para aliviar el calor, crear ciudades resilientes al clima y brindar salud y seguridad pública. Los socios de implementación del plan de acción contra el calor provienen de la región de la zona metropolitana de Phoenix, y se brindan recomendaciones para apoyar la transformación a una ciudad más fresca.

Para ampliar la escala de este enfoque, los miembros del equipo del proyecto recomiendan a) compromiso continuo e inversiones en estos vecindarios para implementar el cambio señalado como vital por los residentes, b) repetir el proceso de planificación de acción contra el calor con líderes comunitarios en otros vecindarios, y c) trabajar con las ciudades, los planificadores urbanos y otras partes interesadas para institucionalizar este proceso, apoyando las políticas y el uso de las métricas propuestas para crear comunidades más frescas.

ContributorsMesserschmidt, Maggie (Contributor) / Guardaro, Melissa (Contributor) / White, Jessica R. (Contributor) / Berisha, Vjollca (Contributor) / Hondula, David M. (Contributor) / Feagan, Mathieu (Contributor) / Grimm, Nancy (Contributor) / Beule, Stacie (Contributor) / Perea, Masavi (Contributor) / Ramirez, Maricruz (Contributor) / Olivas, Eva (Contributor) / Bueno, Jessica (Contributor) / Crummey, David (Contributor) / Winkle, Ryan (Contributor) / Rothballer, Kristin (Contributor) / Mocine-McQueen, Julian (Contributor) / Maurer, Maria (Artist) / Coseo, Paul (Artist) / Crank, Peter J (Designer) / Broadbent, Ashley (Designer) / McCauley, Lisa (Designer) / Nature's Cooling Systems Project (Contributor) / Nature Conservancy (U.S.) (Contributor) / Phoenix Revitalization Corporation (Contributor) / Puente Movement (Contributor) / Maricopa County (Ariz.). Department of Public Health (Contributor) / Central Arizona Conservation Alliance (Contributor) / Arizona State University. Urban Climate Research Center (Contributor) / Arizona State University. Urban Resilience to Extremes Sustainability Research Network (Contributor) / Center for Whole Communities (Contributor) / RAILmesa (Contributor) / Vitalyst Health Foundation (Funder)
Created2022
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Description

Heat vulnerability of urban populations is becoming a major issue of concern with climate change, particularly in the cities of the Southwest United States. In this article we discuss the importance of understanding coupled social and technical systems, how they constitute one another, and how they form the conditions and

Heat vulnerability of urban populations is becoming a major issue of concern with climate change, particularly in the cities of the Southwest United States. In this article we discuss the importance of understanding coupled social and technical systems, how they constitute one another, and how they form the conditions and circumstances in which people experience heat. We discuss the particular situation of Los Angeles and Maricopa Counties, their urban form and the electric grid. We show how vulnerable populations are created by virtue of the age and construction of buildings, the morphology of roads and distribution of buildings on the landscape. Further, the regulatory infrastructure of electricity generation and distribution also contributes to creating differential vulnerability. We contribute to a better understanding of the importance of sociotechnical systems. Social infrastructure includes codes, conventions, rules and regulations; technical systems are the hard systems of pipes, wires, buildings, roads, and power plants. These interact to create lock-in that is an obstacle to addressing issues such as urban heat stress in a novel and equitable manner.

Created2016-08-25
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This study examines the distributional equity of urban tree canopy (UTC) cover for Baltimore, MD, Los Angeles, CA, New York, NY, Philadelphia, PA, Raleigh, NC, Sacramento, CA, and Washington, D.C. using high spatial resolution land cover data and census data. Data are analyzed at the Census Block Group levels using

This study examines the distributional equity of urban tree canopy (UTC) cover for Baltimore, MD, Los Angeles, CA, New York, NY, Philadelphia, PA, Raleigh, NC, Sacramento, CA, and Washington, D.C. using high spatial resolution land cover data and census data. Data are analyzed at the Census Block Group levels using Spearman’s correlation, ordinary least squares regression (OLS), and a spatial autoregressive model (SAR). Across all cities there is a strong positive correlation between UTC cover and median household income. Negative correlations between race and UTC cover exist in bivariate models for some cities, but they are generally not observed using multivariate regressions that include additional variables on income, education, and housing age. SAR models result in higher r-square values compared to the OLS models across all cities, suggesting that spatial autocorrelation is an important feature of our data. Similarities among cities can be found based on shared characteristics of climate, race/ethnicity, and size. Our findings suggest that a suite of variables, including income, contribute to the distribution of UTC cover. These findings can help target simultaneous strategies for UTC goals and environmental justice concerns.

ContributorsSchwarz, Kirsten (Author) / Fragkias, Michail (Author) / Boone, Christopher (Author) / Zhou, Weiqi (Author) / McHale, Melissa (Author) / Grove, J. Morgan (Author) / O'Neil-Dunne, Jarlath (Author) / McFadden, Joseph P. (Author) / Buckley, Geoffrey L. (Author) / Childers, Dan (Author) / Ogden, Laura (Author) / Pincetl, Stephanie Sabine, 1952- (Author) / Pataki, Diane (Author) / Whitmer, Ali (Author) / Cadenasso, Mary L. (Author) / Julie Ann Wrigley Global Institute of Sustainability (Contributor)
Created2015-04-01