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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Imaging the spectral earth an historical epistemology of scientific instrumentation and geographic perception in urban climatology /

May, John Joseph, January 2008 (has links)
Thesis (Ph. D.)--UCLA, 2008. / Vita. Description based on print version record. Includes bibliographical references (leaves 322-345).
12

Urbanization, climate, and frozen ground in Barrow, Alaska

Klene, Anna Elizabeth. January 2005 (has links)
Thesis (Ph.D.)--University of Delaware, 2005. / Principal faculty advisor: Frederick Nelson, Dept. of Geography. Includes bibliographical references.
13

An urban heat island study for building and urban design

Cheung, Kei Wang January 2011 (has links)
A lot of research has been conducted in the past decades on urban heat island (UHI) all over the world. Nevertheless, the UHI effect has not been included in weather data used by building services engineers to design buildings and size their heating and cooling plants. This research was carried out to investigate the UHI effect in Greater Manchester by setting up fixed point monitoring stations over the city. Woodford Met Office ground observation station was selected to be the rural reference point. A multiple regression model was developed to incorporate the heat island effect into the Manchester weather data for engineering usage.It was found that the urban heat island intensity (the difference between the rural and urban area temperatures) can be as high as 8°C in summer and 10°C in winter in Manchester. Clear and calm nocturnal temperature data was used (when maximum heat island occurs ) to find the relationship between the UHI intensity and sky view factor (SVF), distance away from the city centre, evapotranspiration fraction (EF), wind speed, cloud cover and rural reference temperature. Results indicate that all factors have a negative linear relationship with UHI intensity. All measured data were fed into a statistical software package to create general linear regression models. Validation showed that these models were capable of predicting average UHI effect to a good accuracy. The maximum heat island effect peaks are not so accurate. However, an analytical model was developed based on energy balance equations to predict the maximum heat island effect. Validation shows a good prediction for summer but not so good for winter. This is probably due to the lower average UHI intensity in winter than in summer.
14

Using Green Roofs to Mitigate the Effects of Solar Energy on an Unconditioned Building in the Southern United States

Arnold, Jason Lee 09 December 2011 (has links)
The urban heat island (UHI) effect is a phenomenon that results in cities being warmer than the surrounding rural areas, due to a large amount of impervious surfaces. The purpose of this study is to evaluate the effectiveness of green roofs to mitigate the effects of solar energy on a building in the southern United States. In order to test the green roofs, temperatures were monitored inside and on top of unconditioned model buildings with green and with traditional roofs. Over the course of the study, the data collected showed that green roofs provided a significant benefit for the buildings by reducing daily high temperatures during summer and daily low temperatures during winter, while also reducing temperature fluctuation. The findings of this study suggest that a green roof will reduce indoor temperature and rooftop temperature, while providing several other benefits for city inhabitants such as reduced air temperature.
15

Characteristics of the Urban Heat Island in Greater Cincinnati, Ohio: June 25, 2002 to June 24, 2003

BELL, JULIANNE 02 July 2004 (has links)
No description available.
16

a garden in the sky

Russ, Jennifer Lynn 24 May 2004 (has links)
We live in an increasingly urbanized world as people migrate to cities for employment and cultural benefits. Growing and dense urban populations contribute heavily to water pollution and energy waste contributing to global biodiversity extinction. At the same time, contemporary urban areas deliver diminishing returns to residents as cities become cramped, unhealthy, and unattractive. The rooftops of urban buildings offer exciting opportunities for remedying these trends. New rooftop designs highlight the need for more plant life and green space in urban areas, improve energy efficiency, and offer urban residents gardens to enjoy and relax in. Rooftops can enhance buildings in urban areas through landscape design, transforming neglected space into valuable real estate that provides ecological and economic services. Well designed rooftops can enhance property values, assist with primary on-site storm water management, help build energy efficiency, mitigate the urban hear island effect, and filter air and water. A good green roof exists in symbiosis with its neighbors and the city at large. Contemporary rooftop design strives for an ethical stewardship of the earth. I have chosen to design a green roof around the aesthetics and traditions of Japanese horticulture. Japanese landscape design evolved to maximize space and create intricate gardens in small areas and is deep in symbolism and ritual upkeep. / Master of Landscape Architecture
17

Urban heat island in Hong Kong: detection, characterization and evaluation.

January 2005 (has links)
Hui Shuk Ying. / Thesis submitted in: October 2004. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 135-149). / Abstracts in English and Chinese. / ACKNOWLEDGEMENTS --- p.ii / ABSTRACT --- p.iii / 中文摘要 --- p.v / TABLE OF CONTENTS --- p.vi / LIST OF TABLES --- p.viii / LIST OF FIGURES --- p.ix / LIST OF SYMBOLS --- p.xii / Chapter CHAPTER I --- INTRODUCTION --- p.1 / Chapter 1.1. --- Background --- p.1 / Chapter 1.2. --- Situation in Hong Kong --- p.4 / Chapter 1.3. --- Physical setting of Hong Kong --- p.7 / Chapter 1.4. --- Climate of Hong Kong --- p.9 / Chapter 1.5. --- Objectives of the study --- p.12 / Chapter 1.6. --- Significance of the study --- p.12 / Chapter 1.7. --- Organization of the thesis --- p.13 / Chapter CHAPTER II --- LITERATURE REVIEW --- p.14 / Chapter 2.1. --- Introduction --- p.14 / Chapter 2.2. --- Nature of Urban Heat Island (UHI) --- p.15 / Chapter 2.3. --- Characterization of UHI --- p.16 / Chapter 2.3.1. --- Diurnal variation --- p.17 / Chapter 2.3.2. --- Seasonal variation --- p.19 / Chapter 2.3.3. --- Spatial distribution of UHI --- p.20 / Chapter 2.4. --- Effects of weather factors on UHI intensity --- p.22 / Chapter 2.5. --- Relationship between urban factors and UHI intensity --- p.27 / Chapter CHAPTER III --- WEATHER DATA AND METHODOLOGY --- p.34 / Chapter 3.1. --- Surface meteorological observation --- p.34 / Chapter 3.1.1. --- Meteorological stations --- p.35 / Chapter 3.1.2. --- Methods of observation --- p.40 / Chapter 3.2. --- Acquisition and processing of data --- p.42 / Chapter 3.3. --- Detection of urban heat island in Hong Kong --- p.46 / Chapter 3.4. --- "Characterization of UHI intensity, frequency and temporal patterns" --- p.48 / Chapter 3.5. --- Evaluation of relationship between UHI intensity and weather conditions --- p.49 / Chapter 3.6. --- Evaluation of correlation between UHI intensity and city growth --- p.51 / Chapter CHAPTER IV --- RESULTS AND DISCUSSION --- p.52 / Chapter 4.1. --- Temperature evolution in Hong Kong --- p.52 / Chapter 4.1.1. --- Urban center --- p.52 / Chapter 4.1.2. --- New town --- p.57 / Chapter 4.1.3. --- Rural areas --- p.64 / Chapter 4.1.4. --- Discussion of the temperature changes in Hong Kong --- p.68 / Chapter 4.2. --- Urban heat island in Hong Kong --- p.75 / Chapter 4.2.1. --- Basic characteristics of UHI --- p.75 / Chapter 4.2.2. --- Annual patterns of UHI --- p.83 / Chapter 4.2.3. --- Seasonal patterns of UHI --- p.87 / Chapter 4.2.4. --- Discussion of the UHI phenomenon --- p.96 / Chapter 4.3. --- Weather effect on UHI intensity --- p.102 / Chapter 4.3.1. --- UHI phenomena and weather conditions --- p.103 / Chapter 4.3.2. --- Relationship between UHI intensity and meteorological elements --- p.106 / Chapter 4.3.3. --- Discussion of weather effects on UHI intensity --- p.115 / Chapter 4.4. --- Correlation of urban indicators and UHI intensity --- p.121 / Chapter CHAPTER V --- CONCLUSIONS AND RECOMMENDATIONS --- p.128 / Chapter 5.1. --- Summary of findings --- p.128 / Chapter 5.2. --- Limitation of the research --- p.133 / Chapter 5.3. --- Prospects of the study --- p.134 / REFERENCES --- p.135
18

Programa de reabilitação da área central de São Paulo (Procentro) e sua influência na formação da ilha de calor / Rehabilitation program of the central area of São Paulo (Procentro) and its influence on the formation of heat island

Rubbia, Waldir Macho La 02 December 2010 (has links)
A cidade de São Paulo passou por cinco grandes reurbanizações desde 1825 até os dias atuais que intensificaram o uso do solo em detrimento do clima urbano. A partir de 1960 a região central entra em um processo de decadência e, em 2002, é lançado o Programa de Reabilitação da Área Central de São Paulo (Procentro) para reverter esta situação por meio de intervenções distribuídas pelos distritos da Sé e da República que, levando em consideração as questões ambientais, reduzirão a intensidade da ilha de calor paulistana. / The city of São Paulo passed through five major urbanizations since 1825 until today that intensified land use over urban climate. Since 1960 the central region goes into a process of decay, and in 2002 is being launched Rehabilitation Program of the Central Area of São Paulo (Procentro) to reverse this situation through assistance distributed by the Districts of the República and Sé and that taking into consideration environmental issues, reduce the intensity of the heat island of São Paulo.
19

Design and Analysis of an Embedded Pipe Network in Asphalt Pavements to Reduce the Urban Heat Island Effect

Carelli, Jonathan J. 03 May 2010 (has links)
Urban areas contain significant amounts of asphalt pavement. When exposed to the sun, asphalt pavement absorbs solar radiation and stores it as thermal energy raising its temperature. According to the urban heat island effect (UHIE), the pavement releases the thermal energy back to the surrounding air resulting in a rise in local air temperature. A pipe network containing a passing fluid installed in the pavement can reduce the UHIE. The fluid captures the thermal energy stored in the pavement, reducing air and pavement temperatures as well as providing heated water for other applications. The heat transfer/harvesting system can be optimized to produce the desired cooling of the pavements. This research addresses the economic feasibility of a pipe network by design as well as structural performance through computer modeling. To design the pipe network and predict its economic feasibility an Excel spreadsheet was programmed. It requires local air temperature data to determine the yearly temperature profile within the pavement and to calculate the amount of thermal energy that could be extracted. By varying design parameters such as fluid flow rate, it produces a matrix of payback periods. Structural conditions were considered for the installation of the proposed system. To simultaneously evaluate the thermal and structural performance of the pipe network installation, a finite element model was created using COMSOL Multiphysics©. A typical value of solar radiation and a standard truck tire wheel load were applied to the model to simulate the intended application of the pipe network. The result of this thesis is a method and a tool to design and analyze with respect to economic and structural performance a pipe network used to extract the thermal energy stored in asphalt pavements and reduce the UHIE.
20

Extreme heat and its impacts in a changing climate

Coffel, Ethan January 2018 (has links)
Climate change has already increased the frequency, intensity, and duration of heat waves around the world. In the coming decades, this trend will continue and likely accelerate, exposing much of the world’s population to historically unprecedented conditions. In some regions, extreme temperatures (as indexed by the annual maximum temperature) are projected to increase at a faster rate than mean daily maximum temperatures. This dissertation shows that under a high emissions scenario, by 2060 – 2080 models project that the most extreme temperatures could warm by 1 – 2°C more than the warm season average in some regions. This amplified warming of the most extreme temperatures is most pronounced in the eastern U.S., Europe, eastern China, and parts of the Amazon rainforest, and may have substantial implications for heat risk in these regions. This dissertation explores the physical mechanisms driving the projected amplified warming of extremes in climate models and assesses the associated uncertainty. It shows that the amplification is linked to reductions in cloud cover, increased net surface shortwave radiation, and general surface drying as represented by declines in the evaporative fraction. In addition to rising temperatures, atmospheric humidity has been observed to increase in recent decades and models project this trend to continue. As a result, joint heat-humidity metrics indicating heat stress are likely to rapidly increase in the future. This dissertation explores how extreme wet bulb temperatures may change throughout the century and assesses the risk of exceeding a fundamental human heat tolerance limit that has been proposed in prior research. It then combines climate data with spatially explicit population projections to estimate the future population exposure to unprecedented wet bulb temperatures. Several regions stand out as being at particular risk: India, the coastal Middle East, and parts of West Africa are likely to experience extremely high wet bulb temperatures in the future, and rapidly growing populations in these regions will result in large increases in exposure to dangerous heat stress. In some areas, it is possible that wet bulb temperatures could occasionally exceed the proposed human tolerance limit by 2080 under a high emissions scenario, but limiting emissions to a moderate trajectory eliminates this risk. Nevertheless, even with emissions reductions, large portions of the world’s population are projected to experience unprecedented heat and humidity in the future. The projected changes in extreme temperatures will have a variety of impacts on infrastructure and other human systems. This dissertation explores how more frequent and severe hot conditions will impact aircraft takeoff performance by reducing air density and limiting the payload capacity of commercial aircraft. It uses performance models constructed for a variety of aircraft types and projected temperatures to assess the payload reductions that may be required in the future. These payload limits, along with sea level rise, changes in storm patterns, increased atmospheric turbulence, and other effects of climate change, stand to have significant economic and operational impacts on the aviation industry. Finally, this dissertation discusses evidence-based adaptation strategies to reduce the impacts of extreme heat in urban areas. It reviews a body of literature showing that effective strategies exist to both lower urban temperatures on a large scale and drastically reduce heat-related mortality during heat waves. Many adaptation techniques are not costly, but have yet to be widely implemented. Given the rapid increases in climate impacts that are projected in the coming decades, it will be essential to rigorously assess the cost-effectiveness of adaptation techniques and implement the most efficient strategies in both high- and low-income areas.

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