Dissertationen: „Heat and Cool Island“

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Rasul, Azad Othman. „Remote sensing of surface urban cool and heat island dynamics in Erbil, Iraq, between 1992 and 2013“. Thesis, University of Leicester, 2016. http://hdl.handle.net/2381/38508.

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The variation between surface and air temperature within a city and its surrounding area is a result of variations in surface cover, thermal capacity and 3-dimensional geometry. This study examines the spatiotemporal formation of the daytime Surface Urban Cool Island (SUCI) and night-time Surface Urban Heat Island (SUHI) effect in Erbil, Iraq, as a case study for cities in semi-arid climates more generally. It furthermore quantifies the influence of rapid urban expansion on the urban heat/cool island effect over a 20 year period. Satellite images acquired by Landsat 4, 5, 7 and 8 between 1992 and 2013 are used to retrieve Land Surface Temperature (LST). Normalised Ratio Scale (NRS) is applied to the multi-mission Landsat data, which is used to adjust the temperature range for different acquisition times of images within the same temporal range. In addition, LST data from the Moderate Resolution Imaging Spectroradiometer (MODIS) on board Aqua and Terra from January 2003 to December 2014 are analysed. In order to establish the drivers of the observed patterns of LST and SUCI/SUHI, the relationships of LST with wetness, greenness, NDVI, soil moisture and other variables are assessed. The results indicate that during the daytime in summer, autumn and winter, densely built-up areas had lower LST acting as cool islands (SUCI) compared to the non-urbanised area around the city. In contrast, at night-time, Erbil experienced higher LST and demonstrated a significant SUHI effect. The mean LST of the newly urbanised and vegetated areas between 1992 and 2013 decreased by 2.28°C and 7.29°C respectively. Soil moisture (wetness) is the main marker of the SUCI/SUHI effect, whilst urban expansion may cause a decrease of daytime LST in dry climate zones. The NRS method is appropriate for detecting temperature trends greater than 2°C in Landsat data.

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Olsen, Kerby Andrew. „EVALUATING URBAN DESIGN STRATEGIES FOR CLIMATE CHANGE ADAPTATION IN LOS ANGELES“. DigitalCommons@CalPoly, 2015. https://digitalcommons.calpoly.edu/theses/1427.

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Human interference with the Earth’s climate, through the release of greenhouse gasses (GHGs), is estimated to have already increased average statewide temperatures in California by 1.7° Fahrenheit (F), with a further 2.7°F of warming expected by mid-century. The negative impacts of increased temperatures may be especially acute in mid-latitude cities that currently enjoy a mild climate, such as Los Angeles (LA), which are projected to warm to a point that will significantly affect human health and well being. The built environment increases urban temperatures through building materials that readily absorb heat from the sun, a lack of vegetation, a lack of pervious surface area, and anthropogenic heat. Local governments can take action to help their cities adapt to future temperatures through changes to building materials, urban design and infrastructure. This study evaluates six urban design strategies for reducing temperatures and therefore adapting to increased heat in LA: cool roofs, cool pavements, solar panels, tree planting, structural shading and green roofs. The methods used in this analysis include a cost-effectiveness analysis, key stakeholder interviews, and case studies from other cities in the US. Findings indicate that cool roofs are the most cost-effective strategy for urban heat island mitigation, with cool pavements and tree planting also cost-effective. Findings from stakeholder interviews indicate that political feasibility is high for all strategies except structural shading, which was thought to be costly and difficult to implement. However, significant political barriers were also identified for tree planting and green roofs. Findings from four case studies indicate that climate adaptation policies should emphasize co-benefits, include flexible design standards, and provide financial or performance-based incentives for property owners or developers. Specific recommendations for implementing climate adaptation measures are provided for urban planners, policy makers, urban designers and architects in Los Angeles.

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Souza, Ana Cristina Inacio de. „Avaliação comparativa da refletância solar de tintas para telhas com o uso de \"pigmento frio\" e convencional nas cores cinza claro e escuro“. Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/3/3153/tde-26022018-153059/.

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O uso de \"pigmento frio\" é uma alternativa para minimizar os efeitos de \"ilhas de calor\" em grandes cidades como São Paulo. Este tipo de pigmento proporciona o desenvolvimento de fórmulas de tinta para aplicação em coberturas com cores escuras, próximo ao preto, apresentando refletância solar (SR) maior. Neste estudo, foi formulado um grupo de tintas na cor cinza claro e outro na cor cinza escuro. O primeiro grupo de tintas foi preparado com adição de pigmento preto convencional, o negro de fumo que possui natureza orgânica e o segundo grupo de tintas foi preparado com adição de \"pigmento frio\", que possui natureza inorgânica. A fração pigmentária de ambos os grupos de tintas foi preparada com auxílio do software \"CoolSim\". A revisão bibliográfica mostra que as tintas preparadas com pigmentos de natureza orgânica apresentam baixa refletância solar enquanto que as tintas preparadas com o uso do \"pigmento frio\" apresentam maior refletância solar. Os resultados de refletância solar de ambos os grupos de tintas confirmam os dados apresentados na revisão da bibliográfica. As fórmulas preparadas com o uso de \"pigmento frio\", mesmo tendo cor escura, resulta em produto mais adequado para a aplicação em superfície de cobertura como telha, devido sua capacidade de absorver menos calor, o que contribui na redução da temperatura do edifício, reduzindo a necessidade de uso de ar condicionado e auxiliando na redução do consumo de energia.
The use of \"cool pigment\" is one of the alternatives to minimize the effects of \"heat islands\" in big cities like São Paulo. This type of pigment provides the development of formulas for painting roofs with dark colors, near black, but showing higher solar reflectance (SR) than conventional pigments. In this study, a group of paint was formulated in light gray color and the other in dark gray color. The first group of paints was prepared with addition of conventional black pigment which is the carbon black that has organic nature. The second group of paints was prepared with addition of \"cool pigment\", which has inorganic nature. The pigment fraction of both groups of paints was obtained using the software \"CoolSim\". The literature review shows that finishes obtained with paints prepared with organic nature pigment has lower solar reflectance and finishes obtained with paints prepared with addition of \"cool pigment\", with inorganic nature, have a higher solar reflectance. The results of the study show that the solar reflectance of both groups of paint confirms the data obtained in the literature review. The paint formulas prepared with addition of \"cool pigment\", even presenting dark color, resulted in film more adequate for the application in surfaces of roofs and tiles due their capacity to absorb less heat. The use of \"cool pigment\" in formulas allow to obtain paints that can contribute to the reduction of the temperature of the building, by reduction the need to use air conditioning, resulting in lower energy consumption.

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Iizawa, Isao. „Urban Heat Island Circulation“. Kyoto University, 2009. http://hdl.handle.net/2433/123927.

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Kyoto University (京都大学)
0048
新制・課程博士
博士(人間・環境学)
甲第14712号
人博第448号
新制||人||110(附属図書館)
20||人博||448(吉田南総合図書館)
UT51-2009-D424
京都大学大学院人間・環境学研究科環境相関研究専攻
(主査)准教授酒井敏, 教授鎌田浩毅, 教授石川尚人
学位規則第4条第1項該当

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Stewart, Iain Douglas. „Redefining the urban heat island“. Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/38069.

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The effect of urban development on local thermal climate is ostensibly well documented in scientific literature. Since the nineteenth century, observations of “urban-rural” air temperature differences (ΔTu-r), or urban heat island magnitudes, have been reported for hundreds of cities worldwide. The historical and geographical scope of the heat island literature is impressive. Over time, however, methodologists have raised concerns about the rigor and authenticity of that literature, especially regarding the definition, measurement, and reporting of heat island magnitudes. Indiscriminate use of “urban” and “rural” by heat island investigators to describe their field sites is a particular concern. Much confusion now surrounds the physical and cultural characteristics of so-called urban and rural sites in heat island literature. This thesis confronts these concerns through two approaches. The first approach synthesizes and evaluates a sample of 190 observational heat island studies from the period 1950 to 2007. The synthesis uses nine criteria of scientific method and communication to critically assess the experimental quality of each study. Results are discouraging: the mean quality score of the literature sample is just 50 percent, and nearly one-half of the reported heat island magnitudes are judged to be scientifically indefensible on account of incomplete or incompetent reporting. The second approach develops a landscape classification system to standardize reporting of heat island field sites and temperatures in all cities. The local climate zone (LCZ) system comprises 17 zones and is the first comprehensive climate-based classification of urban and rural landscapes for heat island investigators. Each zone represents an area that is local in scale and unique in land cover, building morphology, and screen-level thermal climate. Results show that the new classification leads to a more purposeful interpretation of heat island magnitude as ΔTLCZ, and thereby constrains the operational use of ΔTu-r to climatologically defined and universally recognized urban and rural zones. The thesis concludes with a conceptual typology of urban heat island magnitudes, and a list of specific guidelines and recommendations to improve methodology and communication in heat island studies.

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Thompson, Nicholas Kim. „Cool-water Carbonate Sedimentology and Sequence Stratigraphy of the Waitaki Region, South Island, New Zealand“. Thesis, University of Canterbury. Geological Sciences, 2013. http://hdl.handle.net/10092/8799.

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In the mid-Cenozoic, New Zealand underwent slow subsidence interspersed with unconformity development, however significant controversy exists around both the extent of submergence below sea level during this period of maximum drowning, as well as the causes of these unconformities. Detailed field observations, combined with extensive petrographic analyses, stable isotopes, cathodoluminescence, and thin section staining were used to develop lithofacies, depositional, and sequence stratigraphic models of the mid-Cenozoic succession in the Waitaki region, South Island, to address these controversies. Twelve facies types have been described for Late Eocene-Early Miocene sedimentary rocks, leading to the identification of two major (Mid Oligocene & Early Miocene) and one minor (Late Oligocene) sequence boundaries. Surtseyan volcanism in the east produced a palaeohigh, resulting in a submerged rimmed cool-water carbonate platform, with low-lying land to the west. This eastern palaeohigh developed karst during sea-level lowstands, which correlate with silty submarine bored hardgrounds in the west. Glauconitic and phosphatic facies deposited during early marine transgression suggest an authigenic factory supplied by terrigenous clays existed during lowered sea level that was progressively shut down in favour of a carbonate factory as sea level rose and terrigenous supply decreased. The eastern palaeohigh served to nucleate this carbonate factory by raising the sea floor above the influence of siliciclastic sediment supply and providing a shallow substrate for marine colonisation. The higher energy eastern facies display dissolution of aragonitic taxa, while deeper western facies retained an aragonitic assemblage. This early bathymetric high created a barrier to submarine currents, but was gradually reduced by erosion during subsequent lowstands. Calcareous facies were often subjected to minor seafloor cement precipitation to shallow burial diagenesis, while eastern facies developed some meteoric cement during subaerial exposure. Comparisons between sea-level change in the study area and the New Zealand megasequence indicate eustatic changes as the primary driver of water depth in the Waitaki region until the development of the modern plate boundary in the Early Miocene.

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Zhang, Tianyao. „A study on the heat transfer and energy performance implications of cool roofs“. Thesis, Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/52977.

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In this study, we examined the effect of cool roofs on commercial and residential buildings in each climate zone, by looking at monitored case studies and DOE-2 simulations from various sources of literature; and using an online tool - the Cool Roof Calculator and a simple COP ratio model to validate the results of the case studies. It was found that the Cool Roof Calculator does not take building form into account, hence a sensitivity analysis was first conducted to rank the importance of various building parameters against one another. The analysis was conducted on the EPC normative building energy model. Results indicated that roof absorptance coefficient, aspect ratio and number of floors were the three parameters that either ranked highest or were important parameters, and were chosen for further parametric analysis to evaluate the impact of these building parameters on total building loads. A simple COP ratio model was also developed to validate the results from the literature review and Cool Roof Calculator, and it was found that in terms of cost, for a prototype medium-sized commercial building, it is always beneficial to use a white roof, but cities in northern climates may have little advantage, and insulation may be a better choice.

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Blazer, Mark A. „Architectural strategies in reducing heat gain in the sub-tropical urban heat island“. [Tampa, Fla] : University of South Florida, 2008. http://purl.fcla.edu/usf/dc/et/SFE0002781.

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Costa, Eduino Rodrigues da. „O CAMPO TERMO-HIGROMÉTRICO INTRA-URBANO E A FORMAÇÃO DE ILHAS DE CALOR E DE FRESCOR URBANAS EM SANTA MARIA/RS“. Universidade Federal de Santa Maria, 2009. http://repositorio.ufsm.br/handle/1/9313.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Urbanization and the changes imposed by man disturb the complex natural system, modifying the elements and characteristics of climate on a local scale. Considering the influence of urbanization as derived from the fact that the local climate and responsible for the generation of an urban environment specifically, this work was to analyze the field thermo-hygrometric and the formation of heat islands and urban cool in Santa Maria RS (Rio Grande do Sul, State of Southern of Brazil), relating these variables geourbans and geoecologycs in the study area. To accomplish this work was used the methodology of the transects, consisting of mobile collections in points pre-established. It was established two transects for data collection of temperature and relative humidity of the atmospheric air: one has the direction more or less in a north/northwest-south/southeast (NNW-SSE), linking Street Sete de Setembro , in Neighborhood Perpétuo Socorro , the end Fernando Ferrari Avenue in Neighborhood Nossa Senhora de Lourdes and the other in the east/northeastwest/southwest (WSW-ENE), linking the Street Major Duarte to get Street Venâncio Aires near the Arroio Cadena at Central portion of the Santa Maria City. The data were collected on days August 14, 2008 and January 06, 2009, the area was under the weather for the South Atlantic Polar Mass in winter time and the Old Polar Mass or modified in the summer, respectively. Were made cotte measures at five different times (9, 12, 15h, 18h and 21h), in order to verify the responses of thermal and humidity from the points pre-established and distributed along the transects, totaling 13 points of measures along the transect 1 (NNWSSE) and 15 in the transect 2 (ENE-WSW). Armed with the data of temperature and humidity, were made cartograms of the field thermo-hygrometric. For this application was used the Software Surfer for Windows 8.0. In the preparation of cartograms of the thermal field were established color scales to represent the values of temperature, so the cool colors were associated with lower temperatures and the warm colors at higher temperatures. Cartograms of hygrometric field values were represented in the cartogram using a variation of blue scale, so the lighter blue was used to represent the values of lower humidity and dark blue for higher values. The results highlight that the hygrometric and thermal fields of the coverage area of the transects, both on the day of collection in the field of Mass Polar Atlantic in winter time and in the field of Old Polar Mass or modified in the summer, need to move apparent daily sun exposure of the slopes and to solar radiation. By analyzing the thermal field of January 06, 2009 in five hours of collection, it became clear the migratory movements of the heat islands of the eastern slope, during the morning, to the slopes facing the north and west quadrant, during periods of midday and afternoon. The weather conditions that occurred on January 06, 2009 (summer), with clear skies, calm winds and a light with high incidence of solar radiation on the surface, favored the formation of heat islands and freshness of magnitude rating, strong and very strong. Was verified the thermal contrast between the center and periphery of the study area.
A urbanização e as transformações impostas pela ação do homem desequilibram o complexo sistema natural, modificando os elementos e as características do clima na escala local. Considerando a influência da urbanização como fato derivador do clima local e responsável pela geração de um clima especificamente urbano, este trabalho, teve por objetivo analisar o campo termohigrométrico, bem como a formação de ilhas de calor e de frescor urbanas em Santa Maria/RS, relacionando-as as variáveis geourbanas e geoecológicas existentes na área de estudo. Para isso utilizou-se a metodologia dos transectos, que consiste em coletas móveis em pontos pré-estabelecidos. Foi estabelecido dois transectos para a coleta dos dados de temperatura e umidade relativa do ar: um no sentido norte/noroeste-sul/sudeste (NNW-SSE), ligando a rua Sete de Setembro, no bairro Perpétuo Socorro, ao final da avenida Fernando Ferrari no bairro Nossa Senhora de Lourdes e o outro no sentido leste/nordeste-oeste/sudoeste (ENE-WSW), ligando a rua Major Duarte ao começo da rua Venâncio Aires próximo, ao Arroio Cadena. Os dados foram coletados nos dias 14 de agosto de 2008 e 06 de janeiro de 2009, sob domínio das condições atmosféricas pela Massa Polar Atlântica no inverno e pela Massa Polar Velha ou modificada no verão, respectivamente. As coletas foram realizadas em cinco horários diferentes (9h, 12h, 15h, 18h e 21h), com o intuito de verificar as respostas térmicas e de umidade dos pontos pré-estabelecidos e distribuídos ao longo dos transectos, num total de 13 pontos ao longo do transecto 1 (NNW-SSE) e de 15 no transecto 2 (ENE-WSW). De posse dos dados de temperatura e umidade do ar, foram confeccionados os cartogramas do campo termo-higrométrico. Para tal foi utilizado o aplicativo Surfer for Windows 8.0. Na elaboração dos cartogramas do campo térmico foram estabelecidas escalas de cores para os valores de temperatura, onde as cores frias foram associadas a temperaturas mais baixas e as cores quentes a temperaturas mais altas. Nos cartogramas do campo higrométrico os valores de umidade foram representados utilizando uma variação da cor azul. Assim, o azul mais claro foi utilizado para representar os valores de umidade mais baixos e, a cor azul escura, para os valores mais altos. Como resultados destaca-se que os campos térmico e higrométrico da área de abrangência dos transectos, tanto no dia de coleta sob domínio da Massa Polar Atlântica, no inverno, quanto no domínio da Massa Polar Velha ou modificada, no verão, estão condicionados ao movimento aparente diário do sol e a exposição das vertentes à radiação solar. Ao analisar o campo térmico do dia 06 de janeiro de 2009, nos cinco horários de coleta, percebe-se o movimento migratório das ilhas de calor da vertente leste, para as vertentes voltadas para o quadrante norte e oeste. As condições de tempo ocorridas no dia 06 de janeiro de 2009 (verão), com céu limpo, ventos calmos a leve e com forte incidência de radiação solar na superfície, favoreceram a formação de ilhas de calor e de frescor de magnitude media, forte e muito forte, bem como o contraste térmico entre o centro e a periferia da área de estudo.

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Kim, Jun-Pill. „LAND-USE PLANNING AND THE URBAN HEAT ISLAND EFFECT“. The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1253215365.

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Memon, Rizwan Ahmed. „Statistical analysis of urban heat island and modeling of heat generation within street canyon“. Thesis, Click to view the E-thesis via HKUTO, 2009. http://sunzi.lib.hku.hk/hkuto/record/B42664445.

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Mavrogianni, A. „Modelling domestic space heating demand and heat wave vulnerability within the London urban heat island“. Thesis, University College London (University of London), 2012. http://discovery.ucl.ac.uk/1352829/.

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The combined effect of climate change and the urban heat island phenomenon is likely to reduce the space heating needs and cold-related mortality risk of urban populations in mid latitude countries during winter; however, it is also expected to increase overheating and heat-related deaths during summer. Identifying the determinant factors for energy demand and thermal comfort across a city is hence a key requirement for energy efficient retrofit and public health strategies. The aim of this thesis was to assess the relative impact of urban warming, built form and fabric characteristics on domestic energy use and overheating risk across a major city, using London as a case study. Two housing stock models were developed: a heat demand model based on steady-state energy use calculation techniques and a multiple linear regression overheating risk meta-model of an existing dynamic thermal simulation program. Input data was derived from existing Geographic Information System databases, national housing surveys and local urban air temperature models. The heat demand model successfully reproduced the ranking of urban areas based on their actual gas consumption (R² = 0.817) in a case study area containing 8.6% of London's dwelling stock. The heat island was found to decrease the average annual domestic heating load by 14% in these urban areas compared to a rural reference site. It was shown that the overheating meta-model can replicate the output of the thermal simulation program (R² = 0.763). It was indicated that highly exposed dwelling types, such as top floor flats and bungalows, as well as internally insulated buildings are likely to present an indoor overheating problem during periods of hot weather. However, the agreement between modelled overheating levels and monitored data collected in 101 London homes in summer 2009 was relatively weak, thus highlighting the modifying role of occupant controlled ventilation for indoor thermal conditions.

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Siu, Leong-wai, und 蕭亮煒. „Quantifying the urban heat island (UHI) intensity in Hong Kong“. Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B45692567.

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Yang, Joseph H. (Joseph Hansuk). „The curious case of urban heat island : a systems analysis“. Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/107347.

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Thesis: S.M. in Engineering, Massachusetts Institute of Technology, School of Engineering, Institute for Data, Systems, and Society, System Design and Management Program, 2016.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 59-60).
This thesis provides insights into the urban heat island (UHI) effect using a model of the urban microclimate that integrates the urban geometry, anthropogenic heat emission and the rural weather condition. The study builds upon the Urban Weather Generator (UWG), a numerical simulation program previously developed at MIT, incorporating such improvements as monthly disaggregation of ground sink temperature, Depart of Energy (DOE) commercial reference building templates, hourly schedule of building and non-building anthropogenic heat loads, and the development of an Excel user interface. Simulation generated from the updated model offers an explanation of the underlying mechanisms driving the UHI impact and the interactions between elements of the urban weather system. Based on the sensible energy flux transferred to the urban air mass, an UHI indicator to express the severity of UHI effect by the urban landscape is also developed to help urban planners estimate and mitigate the impact.
by Joseph H. Yang
S.M. in Engineering

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Han, Yilong. „A Bio-inspired Solution to Mitigate Urban Heat Island Effects“. Thesis, Virginia Tech, 2014. http://hdl.handle.net/10919/64310.

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Over the last decade, rapidly growing world energy consumption is leading to supply difficulties, exhaustion of fossil energy resources, and global environmental deterioration. More than one-third of energy expenditure is attributable to buildings. Urbanization is intensifying these trends with tighter spatial interrelationships among buildings. This is escalating building energy consumption due to the mutual impact of buildings on each other and, as a result, exacerbating Urban Heat Island (UHI) effects. I sought solutions to this significant engineering issue from nature, and discovered a similar heat island effect in flowers, namely the micro-greenhouse effect. However, a special cooling effect has been observed in a peculiar temperate flower, Galanthus nivalis, which generates cooler intrafloral temperatures. In this research, I studied the special retro-reflectance of the flower petals, which has been suggested as a possible contributor to this cooling effect, and implemented a bio-inspired retro-reflective pattern for building envelopes. I conducted cross-regional energy simulation of building networks in a dynamic simulation environment in order to examine its thermal-energy impact. I found that building surface temperatures dropped considerably when neighboring buildings were retrofitted with my bio-inspired retro-reflective facade. I concluded that my bio-inspired retro-reflective pattern for building envelopes; (1) lessens the reflected heat of solar radiation in spatially-proximal buildings leading to reduced UHI, and (2) reduces the energy required for cooling and, therefore, energy consumption. The research has further implications and contributions on building design, urban planning, development of retro-reflective technology, and environmental conservation.
Master of Science

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Van, Tol Zachary Charles. „Analysis of Urban Heat Island Intensity Through Air Mass Persistence“. Thesis, Virginia Tech, 2021. http://hdl.handle.net/10919/103468.

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The bulk of synoptic weather type research related to urban climate focuses on human health impacts; however, recent studies have begun to quantify urban heat island (UHI) magnitudes by weather type, or air mass classification. This study presents an analysis of UHI intensity through synoptic-scale air mass persistence during the spring season for four UHI-prone United States cities. Historical daily weather types for Birmingham, Alabama; Charlotte, North Carolina; Louisville, Kentucky; and St. Louis, Missouri were extracted from the Spatial Synoptic Classification database for 40 years from 1980 through 2019. Daily minimum surface air temperature data were downloaded from the Global Historical Climate Network to compute UHI. The historical daily weather type data were converted into a record of persistence, or the length of consecutive days that a synoptic weather type was in place at each location. A descriptive climatology of SSC weather types and UHI at each location was constructed before UHI magnitudes were segregated by day of persistence and examined for differences in intensity. Climatologically, the four urban areas experienced an increase in warm weather types at the expense of cool weather types throughout the study period. Specifically, the persistence of moist tropical weather types increased at a statistically significant rate at Birmingham, Charlotte, and Louisville, consistent with the theorized northward migration of the mid-latitude jet stream. Also evident is a statistically significant increase in UHI frequency and intensity at Birmingham, Charlotte, and Louisville during the study period. Results show that the moisture character of a weather type is an important differentiating factor in UHI intensification, as the mean UHI was found to increase with the persistence of dry weather types and decrease with the persistence of moist weather types, presumably reflecting differences in radiational heating and cooling with atmospheric moisture content. The most intense UHIs and the largest UHI magnitude increase by day of persistence are associated with dry weather types, which have become more frequent since 1980. The findings suggest that larger magnitude UHIs may become more common in the future should dry weather type persistence continue to increase. Higher urban temperatures put human health at risk due to a well-linked relationship between heat and mortality and morbidity rates. The effects of heat are cumulative; the more common persistent, oppressive days become, the larger the impact.
Master of Science
Most of the research related to variation in the warmth of an urban area relative to the surrounding rural area, or the urban heat island (UHI) effect, under varying air mass conditions (temperature and humidity) has focused on human health impacts. This study examines UHI intensity through regional-scale air mass persistence during the spring season in four UHI-prone United States cities. Historical daily air mass conditions in the form of weather types for Birmingham, Alabama; Charlotte, North Carolina; Louisville, Kentucky; and St. Louis, Missouri were downloaded from the Spatial Synoptic Classification database for the 40 years from 1980 to 2019. UHI values for each urban location were calculated using daily minimum air temperature data from the Global Historical Climate Network. A descriptive climatology of weather types and UHI magnitude at each of the four urban locations established long-term means and trends before analysis of UHI intensity through varying weather type residence times, or persistence. Time series analyses align with previous indications of an increasing persistence of weather types and an increase in the frequency of warm weather types at the expense of cool weather types during the spring season. An increase in both UHI frequency and intensity occurred through the study period at Birmingham, Charlotte, and Louisville. The mean intensity of the UHI was found to increase with the persistence of weather types of low humidity and to decrease with the persistence of moist weather types. The largest mean UHI and the largest UHI magnitude increase by day of persistence are associated with low humidity weather types, which have become more frequent since 1980. The impacts of heat are cumulative; persistently elevated temperatures are detrimental to human health.

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Cheung, Kei Wang. „An urban heat island study for building and urban design“. Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/an-urban-heat-island-study-for-building-and-urban-design(642cce92-6606-443c-9c26-6754e28f2d41).html.

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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.

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Yang, Lina. „City ventilation of Hong Kong by thermal buoyancy“. Click to view the E-thesis via HKUTO, 2009. http://sunzi.lib.hku.hk/hkuto/record/B42841380.

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Jing, Cheng Tao. „Analysis of urban heat island effect of Macao by ARPS simulation“. Thesis, University of Macau, 2008. http://umaclib3.umac.mo/record=b1939508.

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20

Mohd, Nasir Siti Diana Nabilah. „The influence of building configuration on the urban heat island effect“. Thesis, University of Sheffield, 2017. http://etheses.whiterose.ac.uk/20289/.

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The process of urbanisation has a major influence in determining the microclimate condition in urban areas through physical and social developments. With the estimation of 67 % world population will be living in the urban areas in 2050, modification of urban climate through urban heating will continually occur by adapting artificial urban surfaces to accommodate the demands from urban dwellers. This thesis highlighted the mitigation strategy by applying solar collector system embedded underneath road pavements, RPSC due to the concern of heat release from the ground road surfaces to the nearby air temperature, which indirectly affects the outdoor thermal comfort and elevates the urban heat island (UHI) effect. The performance of hydronic RPSC system was determined by factoring the influence of building configurations, termed as urban canyon. 3D CFD simulation studies of Standard k-ε RANS model coupled with Solar Load and DO radiation model were carried out to simulate the integration of hydronic RPSC with urban canyons. Validations of the simulation results were done against previous published works and the thesis’ thermal data collections within Kuala Lumpur conurbation centre. Based on the simulation and data collection, it was found that building configurations with symmetrical canyon height had clearly increased the performance of RPSC system in surface temperature reduction and potential temperature collection as compared to other comparative settings. There was an increasing trend by changing the aspect ratio (AR) 1 to AR 2 with a slightly drop in the performance to AR 3 and AR 4 due to shadow effects. Findings from the data collection however, disagreed the trend due to a major factor from the solar intensity of the measured days affecting the temperature values. Furthermore, application of RPSC system in deep street canyons showed the potential of the system to reduce up to 4 °C air temperature at the pedestrian level; however, it was still insufficient to achieve an outdoor comfort temperature level.

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Bassett, Richard. „Quantifying the influence of wind advection on the urban heat island“. Thesis, University of Birmingham, 2018. http://etheses.bham.ac.uk//id/eprint/8411/.

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Although the urban heat island (UHI) is well studied, the dynamic nature (i.e. with wind) receives little attention. The concept, urban heat advection (UHA), can warm air temperatures in surrounding rural areas. This may lead to a misinterpretation of local climate and bias in long-term climate records. Using observational analysis and numerical modelling this thesis investigates these limitations by spatially quantifying UHA. A methodology to separate UHA from the background air temperature was applied to a high-density urban observation network in the city of Birmingham, UK demonstrating mean downwind UHA of 0.4oC and up to 1.2oC at individual stations (wind speeds 2 – 3 m s-1). This UHA methodology was adapted to show that even small urban areas (~1 km2) can produce a mean UHA of 0.6oC. TheWeather Research & Forecasting numerical model was used to refine the UHA methodology (accounting for regional heat advection) and conduct semiidealised simulations. Here, a square city with 16 km size produced UHA of 2.4oC at the city edge, with 0.5oC warming extending 9 km downwind. A relationship was found between city size and UHA intensity, enabling statistical scaling. This demonstrated an approach to estimate UHA without the need for computationally expensive simulations.

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Chen, Bao-Liang. „Capture solar energy and reduce heat-island effect from asphalt pavement“. Worcester, Mass. : Worcester Polytechnic Institute, 2008. http://www.wpi.edu/Pubs/ETD/Available/etd-121508-154718/.

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23

Jkaoua, Zineb. „Méthodologie participative pour une rénovation urbaine durable : influence du microclimat sur le confort des usagers“. Electronic Thesis or Diss., Bordeaux, 2024. http://www.theses.fr/2024BORD0160.

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Le changement climatique devient de plus en plus préoccupant. En effet, parmi ses conséquences, nous subissons des vagues de chaleur estivale plus fréquentes, plus longues et plus intenses. Ces épisodes de chaleur entraînent des répercussions considérables en milieu urbain. Ils rendent les activités quotidiennes dans les espaces de vie extérieurs et intérieurs extrêmement inconfortables, engendrent des conséquences néfastes sur la santé publique parfois létale et augmentent la demande énergétique pour la climatisation des bâtiments. Ces constats soulignent l'importance de la transition vers des villes plus résilientes, respectueuses de l'environnement.Dans ce contexte, les priorités d’actions architecturales se doivent d’évoluer. En effet, il y a lieu désormais de fournir les efforts nécessaires au réaménagement des espaces urbains dans les zones densément peuplées et à la réhabilitation des bâtiments existants, tout en procédant dans le même temps à la réalisation des bâtiments neufs économes en énergie.En mettant l'accent sur le réaménagement urbain et la réhabilitation des bâtiments, la démarche, participative, proposée vient conforter les bâtiments existants et renforcer l’attractivité des espaces extérieurs, favorisant ainsi les modes de vie durables et la réalisation d’avancées significatives participant à la lutte contre le changement climatique. Les travaux menés dans cette thèse s’intéressent au confort perçu et à l’amélioration de la qualité de vie, sujets prioritaires des bureaux d’études spécialisés, des maitres d’ouvrage et des collectivités locales.Dans ce but, cette thèse propose d’offrir, aux concepteurs et aux décideurs, des outils adaptés à la pratique, agissant de la programmation à l’exploitation d’un projet de rénovation urbaine et ce, en considérant l’aspect climatique local et l’aspect subjectif.Notre démarche scientifique a consisté à analyser un ensemble d’outils d’aide à la décision. Certains modèles de caractérisation du confort hygrothermique sont complexes et prennent en considération plusieurs paramètres pour évaluer le confort des usagers. La première étape a comporté une analyse de sensibilité d’un indice de confort objectif UTCI (Universal Thermal Climate Index) afin de repérer les paramètres significatifs qui nécessitent une mesure. La seconde étape a impliqué la validation d’un indice moyen de confort perçu à l’échelle urbaine. En effet, cette démarche s'est concrétisée par l'adoption d’une méthode expérimentale basée sur un état de l’art portant sur les différents indices de confort thermiques. Nous avons ainsi expérimenté la méthodologie intégrant des campagnes de mesures physiques in-situ et des enquêtes standardisées à l’aide des questionnaires adressés aux usagers. Les données recueillies permettent le calcul d’un indice moyen de confort perçu (APCI) et la corrélation de cet indice avec des mesures microclimatiques relevant de l’ingénierie appliquée. L’étape suivante a consisté en une étude numérique simplifiée à l’échelle du bâtiment participant à estimer l’effort requis pour maintenir le confort intérieur généré par une rénovation urbaine. Pour cela, il a fallu utiliser une base de données de bâtiments existante pour simuler le bâtiment et générer, comparer et ajuster des données météorologiques afin d’alimenter l’outil de simulation thermique des bâtiments.Les travaux développés dans cette thèse participent ainsi à poser les bases méthodologiques pratiques pour le développement de projets urbains confortables, étape essentielle vers une urbanisation mieux adaptée aux réalités climatiques futures
The escalating concerns surrounding climate change are evidenced by the exacerbation of summer heat waves, posing significant challenges to urban environments. These heat events detrimentally affect daily activities, compromise public health, and intensify energy demands for building cooling systems. Urgent action is required to transition towards resilient, environmentally friendly cities. This necessitates a reevaluation of architectural priorities towards urban redevelopment and building rehabilitation. This thesis advocates for a participatory approach that empowers the decision-makers and designersto address climate change impacts effectively. By focusing on enhancing perceived comfort and quality of life, this research aligns with the priorities of design offices and project owners. Through a scientific methodology, decision support tools are analyzed to inform urban design processes effectively.This thesis proposes to offer, to the designers and the decision-makers, tools adapted to the practice, acting from the programming to the exploitation of an urban renewal project and this, considering the local climatic aspect and the subjective aspect.The thesis employs a scientific methodology, analyzing various decision support tools to enhance urban comfort. Through sensitivity analysis of the Universal Thermal Climate Index (UTCI), significant parameters affecting comfort are identified, followed by the validation of an average perceived comfort index (APCI) at the urban scale. Utilizing a combination of in-situ measurements and standardized surveys, a perceived average comfort index (APCI) is derived and correlated with microclimatic measurements. Additionally, simplified numerical simulations at the building scale assess the impact of urban renovations on interior comfort, leveraging existing building databases and weather data adjustments.This research contributes practical methodological frameworks essential for the development of comfortable urban projects, vital for urbanization strategies better suited to future climate realities. By integrating local climatic considerations with subjective perceptions, this thesis provides designers and decision-makers with tailored tools to guide urban renewal projects towards enhanced comfort, sustainability, and resilience

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Liu, Bin. „Numerical simulation of urban heat island effect of Macau by ARPS program“. Thesis, University of Macau, 2010. http://umaclib3.umac.mo/record=b2182915.

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Shen, Tianfeng. „Evaluation of urban heat island situation in developed cities of Zhejiang province“. Thesis, University of Nottingham, 2015. http://eprints.nottingham.ac.uk/30441/.

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The rapid and unsustainable urbanization process causes a serious existing thermal environmental problem that aggravates climatic change and generates a higher temperature in urban area than in rural area. Based on literature review, this is the first research that uses field measurement methodology to investigate the urban heat island (UHI) effect in Hangzhou and Ningbo cities of Zhejiang Province. This study aims to investigate reciprocal interaction of UHI effect with urban building energy based on the air temperature and relative humidity measurement in research area. There are three main factors including vegetation cover, urban building configuration and surface material properties, and human activities, contributing to the UHI development. Through using ENVI-met simulation, the study has investigated how the West Lake and the Xixi Wetland ecological areas in the city act as passive thermal comfort systems in improving the outdoor built environment and mitigating UHI effect. However, according to the observation, the UHI effect in Hangzhou is still more intense than that in Ningbo. The monthly average UHII values in Hangzhou ranged between 1℃ and 4℃, whilst the highest monthly average UHII in Ningbo is only as high as 1.5℃. Additionally, the study has evaluated that the UHI effect is most pronounce in winter days, because there is serious air pollution, high concentration of Particulate Matter (PM) and low wind speed in winter days in China. The result has also proved that the night time UHI effect is significantly more intense than the day time UHI effect. It has been validated in the study that UHI effect can be mitigated by three effective strategies, such as the application of cool materials on urban surfaces, modifying urban geometry to improve wind flow and expanding green space in urban areas. Owing to the hourly air temperature and relative humidity collected from strategically selected sites around the city, modified TMY weather dataset has been established. The research employed a case study of China Telecom Business Office Building in Hangzhou to evaluate the impact of UHI on urban building energy consumption. It implies that there is about 20% cooling demand underestimated in the hot months and about 25% heating demand overestimated in the cold months for the office building located in the urban city of Hangzhou, if the building is designed based on currently available weather dataset without considering UHI effect. Based on the application of artificial neural network (ANN) and genetic programming (GP) techniques, the research has provided algorithms to link factors such as “Distance from City Centre”, “Surrounding Albedo”, “Land Use of the Area (residential, commercial, industrial, recreational etc.)”, “Sky View Factor” to predict the UHI intensity for any site compared to a reference site.

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Li, Yuxi. „Singapore’s Building Greenery: A Strategy to Respond to Urban Heat Island Effect“. The University of Arizona, 2016. http://hdl.handle.net/10150/608748.

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Sustainable Built Environments Senior Capstone Project
Climate is an important factor for regional planners whenever they make decisions that concern the future shape and functions of a city. The purpose of this study is to analyze the effects of green infrastructure as a strategy to alleviate urban heat island effect in coastal cities. Taking Singapore as an example, the tropical climate of this country makes it hot and humid throughout the year. Therefore, the main climate issue of Singapore is the urban heat island effect, which raises temperatures in urban areas as opposed to surrounding rural ones. Regional planning authorities in Singapore have taken this climate factor into consideration making this city a great example for my topic.

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Barron-Gafford, Greg A., Rebecca L. Minor, Nathan A. Allen, Alex D. Cronin, Adria E. Brooks und Mitchell A. Pavao-Zuckerman. „The Photovoltaic Heat Island Effect: Larger solar power plants increase local temperatures“. NATURE PUBLISHING GROUP, 2016. http://hdl.handle.net/10150/621943.

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While photovoltaic (PV) renewable energy production has surged, concerns remain about whether or not PV power plants induce a "heat island" (PVHI) effect, much like the increase in ambient temperatures relative to wildlands generates an Urban Heat Island effect in cities. Transitions to PV plants alter the way that incoming energy is reflected back to the atmosphere or absorbed, stored, and reradiated because PV plants change the albedo, vegetation, and structure of the terrain. Prior work on the PVHI has been mostly theoretical or based upon simulated models. Furthermore, past empirical work has been limited in scope to a single biome. Because there are still large uncertainties surrounding the potential for a PHVI effect, we examined the PVHI empirically with experiments that spanned three biomes. We found temperatures over a PV plant were regularly 3-4 degrees C warmer than wildlands at night, which is in direct contrast to other studies based on models that suggested that PV systems should decrease ambient temperatures. Deducing the underlying cause and scale of the PVHI effect and identifying mitigation strategies are key in supporting decision-making regarding PV development, particularly in semiarid landscapes, which are among the most likely for large-scale PV installations.

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Chun, Bum Seok. „Three-Dimensional City Determinants of the Urban Heat Island: A Statistical Approach“. The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1324656659.

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Awino, Hellen Rose Anyango. „Design-integrated Urban Heat Island analysis tool and workflow : development and application“. Thesis, Massachusetts Institute of Technology, 2019. https://hdl.handle.net/1721.1/123577.

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Thesis: S.M., Massachusetts Institute of Technology, Department of Architecture, 2019
"June 2019." Cataloged from PDF version of thesis.
Includes bibliographical references (pages 106-108).
The Urban Heat Island (UHI) effect is a well-studied phenomenon broadly attributed to human activities that transform open terrain into cityscapes. Among global 21st-century concerns, projected trends in population growth, urbanization, and regional climate change could exacerbate the warming in cities and intensify the UHI effect. Yet, microclimate analysis essential to assessing UHI intensity is often neglected, resulting in poor planning practices with adverse effects on health, comfort and energy use within cities. With buildings responsible for substantial quantities of global energy consumption and carbon emissions, this context demands climate-responsive design to achieve better-performing cities. The UHI effect presents an urban design challenge, but only recently has there been a platform for design workflow integration.
Despite existing engines that accurately evaluate UHI intensity in urban environments, architects, designers, and urban planners have often not incorporated such simulation into microclimate studies due to prohibitively expensive computational costs, disconnected workflows within unintuitive or unfamiliar platforms, and uncertainty about difficult-to-obtain urban climatology parameters. These hindrances cause impactful delay within the design feedback loop and often generate a lack of confidence in the simulation process and output. This thesis proposes a Computer-Aided-Design integrated graphical user interface for the Urban Weather Generator (UWG), an urban-scale climate prediction tool developed by Bruno Bueno to simulate microclimatic conditions of urban sites using operational weather station data.
The goal is to make the powerful and computationally cheap engine accessible to design workflows by incorporating it as a plugin within the conventional design software Rhinoceros-3D, and by coupling it with the Local Climate Zone classification scheme developed by urban climate experts lain Stewart and Timothy Oke to standardize quantitative physical descriptions of cities. The proposed update automates geometric parameter extraction and implements a reliable means of urban morphological parameter estimation. As a case study, an iterative urban-scale design exploration is analyzed for selected climates.
by Hellen Rose Anyango Awino.
S.M.
S.M. Massachusetts Institute of Technology, Department of Architecture

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BALIELLO, ANDREA. „The role of road pavements in the phenomenon of Urban Heat Island“. Doctoral thesis, Università degli Studi di Trieste, 2020. http://hdl.handle.net/11368/2961015.

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The thesis aims at proposing a comprehensive study concerning the role of road pavements with respect to the phenomenon of the urban heat island that are generated within the anthropized areas, i.e. all the dynamics that determine a sensible increase of the urban temperatures with respect to that recorded in the surrounding rural environments. More specifically, the core of the research concerns an extensive experimental activity aimed at evaluating different construction solutions to obtain thermal-optimized road pavements. Such solutions consist of clear or colored road pavements made with non-black surfaces and are manufactured with different techniques. Therefore, the main purpose of the whole research regards the definition of advices, indications and guidelines for the production of road pavements able to mitigate the urban heat island and prevent an excessive increase of the urban temperatures. Laboratory and outside activities were scheduled to identify the chromatic characteristics and monitor the thermal properties and responses of the selected technologies. Using a multi-scale approach (from binders to mixtures), an advanced mechanical characterization of the materials was also proposed to assess their suitability since each alternative must ensure adequate standards from functional, safety and durability points of view. A back calculation based on all the collected data permitted the evaluation of the efficacy of the proposed technologies in mitigating the urban heat. Finally, further aspects involved in the use of thermal-optimized pavements, but not directly related to thermal concerns, were also studied: mainly, such aspect regarded the infrastructure-landscape integration of clear or colored surfaces, their possible use as traffic calming measures (and the related road safety matter), their repercussions on the nightly artificial illumination or that needed within the road tunnels. Furthermore, some efforts were also spent in order to investigate their impacts with respect to the human comfort (thermal and visual ones) and the human health. Principal findings of the research stated that some technologies (clear mixtures containing synthetic transparent resins and valuable clear aggregates) were effectively able to contain the temperatures reached during the direct solar exposition (more intense in the summer). The most effective material was useful to lower the maximum reached temperature of about 18 °C with respect to that of a traditional black mixture conventionally employed as wearing courses in urban roads (assumed as reference).

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PREVIATI, ALBERTO. „The subsurface urban heat island in Milan – Anthropogenic heat sources and city-scale modeling of present and future scenarios“. Doctoral thesis, Università degli Studi di Milano-Bicocca, 2022. http://hdl.handle.net/10281/366244.

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Le risorse sotterranee sono essenziali per l’approvvigionamento idrico ed energetico nelle aree urbane. Tuttavia, le attività umane modificano l’assetto naturale del sottosuolo alterandone le condizioni chimico-fisiche, tra cui il regime termico. L'effetto isola di calore nel sottosuolo (SUHI) è stato osservato in diverse città del mondo con temperature da 2 a 8°C più calde rispetto alle aree suburbane, e trend di riscaldamento sono riconducibili al cambiamento climatico e all’urbanizzazione. Infatti, le città ben sviluppate sono anche più colpite a causa della sovrapposizione di fonti di calore antropiche come i seminterrati degli edifici, le superfici asfaltate, i tunnel e gli impianti geotermici. Tale fenomeno ha implicazioni positive (es: maggior efficienza del riscaldamento con geotermia) e negative (es: l'inquinamento termico) sulle acque sotterranee, e l’integrazione di tecniche di monitoraggio e modellazione è fondamentale per quantificare i contributi di calore naturale/antropico in un ambiente complesso e valutarne l'evoluzione futura. Inoltre, gli obiettivi dell'UE sulla mitigazione del cambiamento climatico si concentrano sullo sviluppo di energie rinnovabili per ridurre le emissioni di gas serra. Tra queste, l’energia geotermica superficiale è considerata una valida alternativa ai sistemi di condizionamento tradizionali in quanto è disponibile quasi ovunque ed ha un bassissimo impatto. L'area metropolitana di Milano è una delle regioni maggiormente popolate d'Europa e ha una domanda energetica molto alta. Inoltre, molte attività legate all'urbanizzazione hanno contribuito ad alterarne la superficie e il sottosuolo, ma una valutazione dello stato termico tutt’ora non esiste. Nella prima parte di questo studio, si è stimato il potenziale geotermico a bassa entalpia a scala regionale integrando dati climatici e parametri idrogeologici/termici del sottosuolo. Tramite soluzioni analitiche si è calcolato il potenziale di impianti a circuito chiuso e aperto, considerando: per i primi, i parametri, la temperatura del sottosuolo, e le caratteristiche dello scambiatore, mentre per secondi, l’abbassamento piezometrico e il salto di temperatura ammessi dalla normativa regionale. I risultati sono stati confrontati con gli usi energetici attuali su base comunale, suggerendo la configurazione più favorevole. Nella seconda parte, si dimostra l'estensione dell’isola di calore sotterranea, di intensità fino a 3°C nella città di Milano. L’analisi spazio-temporale dei record di soggiacenza e temperatura ha messo in luce il ruolo dei principali fattori naturali e antropici: il flusso di calore verso l’acquifero è più intenso dove la tavola d’acqua è superficiale e strutture/infrastrutture antropiche sono densamente distribuite. Questo accumulo di calore si riflette in un trend tra +0.1 e +0.4 °C/a che porta fino a +25 MJ/m2/a nel sottosuolo del centro città. Inoltre, sono anche stati osservati gli effetti dell'urbanizzazione sull'abbondanza microbiologica nella falda superficiale. Infine, è stato sviluppato il primo modello numerico (FEM) di flusso e trasporto di calore alla scala urbana, focalizzandosi su (I) la ricostruzione delle eterogeneità del sottosuolo per simulare il trasporto di calore advettivo, (II) una soluzione analitica accoppiata per definire la condizione al contorno termica alla superficie e (III) l'integrazione di molteplici sorgenti di calore naturali/antropiche. Dalla simulazione dello stato attuale emerge che il flusso di calore dagli edifici e dalle infrastrutture/gallerie contribuisce all'85% dell'accumulo di calore annuale (1.4 PJ). Inoltre, il potenziale termico è stato valutato anche numericamente, e si è dimostrato che l’aumento di calore sotterraneo dovuto ai possibili effetti del riscaldamento globale e dell’espansione urbana è ben maggiore rispetto allo sviluppo geotermico che, per questo motivo, dovrebbe essere valorizzato.
Urban areas rely on subsurface resources to produce drinking water and extract low enthalpy geothermal energy. However, atmospheric and subsurface environment modifications by climate change and/or human activities affect the physical-chemical conditions such as the groundwater thermal regime. The subsurface urban heat island (SUHI) effect was documented in several cities worldwide with 2 to 8°C warmer temperatures than in suburban areas and warming trends were linked to global warming and urbanization. Highly developed cities are more impacted due to the superimposition of anthropogenic heat sources (e.g. building basements, asphalted surfaces, tunnels, geothermal installations), and positive (e.g. heating potential) and negative (e.g. thermal pollution) implications for groundwater uses exist. Thus, monitoring and modeling tools are mandatory to disentangle the complex superimposition of positive/negative heat flows from natural/anthropogenic sources and assess the future evolution. Moreover, EU objectives on climate change mitigation are focused on the development of renewable energies to reduce greenhouse gas emissions. Low enthalpy geothermal energy is considered a valid alternative to common heating/cooling techniques as it is available almost everywhere and has a low carbon footprint, especially where thermal energy is supplied by fossil fuels. The Milan city area (MCA) is one of the most densely populated and industrialized regions in Europe and, consequently, has a very high thermal power demand. Moreover, many activities related to urbanization contribute to modify the groundwater environment but their effects on the subsurface thermal status have never been assessed. In the first part of this study, the low enthalpy geothermal potential of the shallow aquifers was assessed at regional scale. Advantageous hydrogeological characteristics (e.g. highly conductive aquifers) were mapped and different analytical solutions used to estimate the thermal potential of ground coupled (GCHP) and groundwater (GWHP) heat pumps. The potential of GCHP was estimated considering subsurface hydraulic/thermal parameters and temperature, climatic data and borehole characteristics. The potential of GWHP was estimated considering the water drawdown and temperature drop allowed by regulation. The results were compared with heat demand rates on a municipal basis and the most profitable configuration was discussed. Successively, the extent and intensity of the SUHI in the MCA was assessed. Natural and anthropogenic controls on groundwater temperatures were revealed analyzing head and temperature records, and the occurrence of an up to 3° C intense SUHI was demonstrated. Vertical heat fluxes to the aquifer are strongly related to the groundwater depth and density of surface structures/infrastructures. This heat accumulation is reflected by a constant warming trend between +0.1 and +0.4 °C/y leading up to a +25 MJ/m2/y heat storage by densely distributed heat sources. Furthermore, the effects of urbanization, SUHI and physical-chemical conditions on the microbiological abundance were assessed by a flow cytometry analysis. Finally, a holistic city-scale fluid flow and heat transport FEM model was developed focusing on (I) the reconstruction of large-scale aquifer heterogeneities to consider the advective dominated heat transport, (II) the definition of the upper thermal boundary by a coupled analytical solution and (III) the integration of natural and human-related fluid/heat sources as transient boundary conditions. A fluid/heat budget analysis revealed the heat flow from buildings, infrastructures and tunnels contributes to 85% of the net annual heat accumulation (1.4 PJ/y). The thermal potential was evaluated numerically, and it was demonstrated that future climate change and city expansion could lead to the highest subsurface warming compared to shallow geothermic development which, for this reason, should be highly supported.

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Alexandri, Eleftheria. „Investigations into mitigating the heat island effect through green roofs and green walls“. Thesis, Cardiff University, 2006. http://orca.cf.ac.uk/55418/.

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This thesis investigates the thermal effect of green roofs and green walls on the built environment and investigates whether they could be used in existing cities so as mitigate the heat island effect. In order to estimate this for various climates, a prognostic, micro-scale, two-dimensional heat and mass transfer model has been developed. In the first chapter the aim, objectives and methodology of the research are established. In the second chapter a literature review of the causes and the consequences of the heat island effect is made, as well as a critique on the use of urban parks for mitigating raised urban temperatures. In the third chapter, a research is carried out where, when and why roofs and walls were covered with vegetation. In the fourth chapter the development of the one-dimensional model is presented, for heat and mass transfer in building materials, a soils, plants and the air. The model is validated with an experiment conducted at a concrete and a vegetated test cell. A comparison is made between green roofs and conventional concrete ones, as well as with white coated roofs for different climates. In the fifth chapter the one-dimensional model is developed into a two-dimensional one and the microclimatic heat and mass transfer model of a typical urban canyon is established. In the sixth chapter, the model is used to investigate the effect of green roofs and green walls for various climates, geometries, canyon orientations and wind directions. From this parametric analysis, an investigation is done on how the raised urban temperatures could lower when the building envelope is covered with vegetation, which could lead to energy savings for cooling and more comfortable outdoor conditions. In the last chapter, conclusions are drawn from the results of this thesis and further research is proposed.

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Kiletico, Micah J. „Integrating Recycled Glass Cullet in Asphalt Roof Shingles to Mitigate Heat Island Effect“. Thesis, Louisiana State University and Agricultural and Mechanical College, 2014. http://hdl.handle.net/10945/43477.

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CIVINS
As an approach to mitigate the harmful effects of Urban Heat Island (UHI), the use of glass cullet in the production of asphalt roof shingles has the potential to be employed as a cool roof strategy. The objective of this study was to test the hypothesis that the use of recycled glass increases solar reflectance index (SRI) without affecting the performance of asphalt roof shingles. In order to evaluate the feasibility of recycled glass for alternative uses, the engineering properties of glass cullet were investigated and compared to conventional aggregates used in the production of asphalt roof shingles. Laboratory samples were then prepared in order to measure solar reflectance properties and strength performance of conventional and recycled glass roof shingles. It is shown that while the use of recycled glass as a replacement to standard ceramic coated black roofing granules on the top surface of asphalt shingles results in an increased SRI, the addition of white pigment powder (anatase ultra fine particles passing mesh #320) mixed together and applied with the surface granules improves reflectance values to meet the cool roof threshold.

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Sobstyl, Jacob Michael. „Urban physics : molecular approach to city texture analysis for controlling Urban Heat Island“. Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/104324.

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Thesis: S.M., Massachusetts Institute of Technology, Department of Civil and Environmental Engineering, 2016.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 126-135).
Defined as intensification of urban air temperatures when compared to their rural surroundings common to cause negative externalities ranging from imperiling human health and comfort to amplifying energy costs and air pollution, Urban Heat Island (UHI) effect has been known to pose a severe burden on the 4.2 billion of people living in cities. With urban population expected to magnify by 2.5 billion by 2050 at an average annual rate of 72 million, ability to control UHI would have consequences of prodigious magnitude. While many UHI mitigation solutions for existent cities have already been established, due to complex nature of urban infrastructure, general and simple to follow design guidelines for building more sustainable urban environments are still missing. Here, we show that with appositeness of statistical physics, we are able to quantify prevailing patterns in cities to a set of few design parameters, which are directly related to UHI. Furthermore, we demonstrate that UHI has the potential to reduce energy bill and depress greenhouse gas emissions (GHG), and therefore cannot be simply generalized into negative realms. As such this work offers a simple to use tool for policy makers and planners to help residents save money on their energy bills, while setting cities and states on the right path towards achieving their GHG targets.
by Jacob Michael Sobstyl.
S.M.

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Sullivan, JoAnn. „Characterization of an Urban Heat Island (UHI) in the Tampa Region of Florida“. Scholar Commons, 2010. https://scholarcommons.usf.edu/etd/1784.

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Numerous research studies have been conducted on the modification of weather and local climate by the urban environment. In studying the urban environment effects, researchers have investigated the urban heat island (UHI), anthropogenic cloud condensation nuclei, anthropogenic heat emissions and other factors. Many of these studies used data sampling networks, while other studies relied solely on computer modeling. This research has taken an approach between the sampling network studies (which were often limited in spatial density) and the pure computer model studies (which lacked the benefits of observational data) to investigate the Tampa Bay Region UHI. The research utilized inexpensive commercially available temperature logging sensors within a 525 km² study area. One hundred temperature logging sensors, deployed within the study area, generated in excess of 250,000 time and temperature data points for analysis. The large number of temperature sensors enabled the generation of detailed spatiotemporal maps of the Tampa Bay Region UHI. Analysis of the data revealed a significant relationship between the percentage of impervious surface in the study area and the intensity of the local UHI delta temperatures. In addition, the analysis identified the existence of micro UHIs within residential areas. These micro UHIs affected readings within the residential areas. In conjunction with the investigation of the relationship between the percentage of impervious surface and the generation of a UHI, wind speed's role as a moderating factor was also investigated. It was found that increases in wind speed are correlated with a lessoning of the observed UHI. Wind speeds above approximately 2 ms-1 exhibit a significant negative relationship to the development of a UHI. The results of this study add to the field of UHI research in subtropical environments.

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Yang, Bo. „Spatio-temporal Analysis of Urban Heat Island and Heat Wave Evolution using Time-series Remote Sensing Images: Method and Applications“. University of Cincinnati / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1552398782461458.

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Bäckström, Erika. „The surface energy balance and climate in an urban park and its surroundings“. Thesis, Uppsala University, Department of Earth Sciences, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-88838.

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På grund av världens växande befolkning och urbaniseringen blir problem relaterade till fenomenet urbana värmeöar mer och mer påtagliga. Eftersom urbana parker kan minska påfrestningen skapad av urbana värmeöar kan de vara ett kraftfullt verktyg vid klimatdesign i städer. Temperaturen nära en yta bestäms av energiutbytet mellan ytan och luften ovanför och det är därför nödvändigt att man förstår energibalansen vid markytan för att kunna hantera parkernas mikroklimat. Syftet med det här arbetet var att studera skillnaderna mellan energibalansen för olika ytor i parken och i dess omgivning och att relatera skillnaderna i energibalanserna till temperaturskillnaderna.

Mätningarna utfördes under tre klara sommardagar i parken Humlegården i centrala Stockholm. Mätutrustningen var monterad på en kärra som flyttades från mätplats till mätplats. Mätplatserna representerade olika typiska ytor i Humlegården och i dess omgivning: en skuggad och en öppen gräsmatta, en öppen och en skuggad grusyta och två asfaltytor, varav en löper i nord-sydlig riktning och en i öst-västlig riktning.

Energiflödena beräknades med hjälp av data för luft- och yttemperatur, vindhastighet, luftfuktighet och nettostrålning.

Resultaten visade att den tydligaste skillnaden mellan gräs- och grusytorna i parken var att gräsytorna hade ett större nedåtriktat latent värmeflöde under natten och ett mindre markvärmeflöde under hela dygnet. Den mest distinkta skillnaden mellan de skuggade och öppna ytorna i parken var att de skuggade ytorna hade mindre energiflöden under dagen och att de till skillnad från de andra ytorna hade ett nedåtriktat sensibelt värmeflöde under dagen. Den största skillnaden mellan ytorna i och utanför parken var att asfaltytorna hade ett större uppåtriktat sensibelt värmeflöde och markvärmeflöde under natten.

Under natten var den svalaste mätplasten den öppna gräsmattan, vilken också var den enda mätplasten med ett nedåtriktat sensibelt värmeflöde under natten. Jämfört med de andra ickeskuggade mätplasterna hade den öppna gräsmattan ett mindre markvärmeflöde. Varmaste mätplasterna under natten var asfaltytorna som även hade ett större uppåtriktat sensibelt och markvärmeflöde än de andra ytorna. Under dagen var de skuggade ytorna i parken de svalaste platserna. De var de enda ytorna med ett nedåtriktat sensibelt värmeflöde och nettostrålningen vid ytan var mindre än för de flesta andra mätplatser.

The world’s growing population and the increasing urbanization has made problems related to the urban heat island phenomenon to become more pronounced and since urban parks reduce the stress produced by the urban heat island they can be powerful tools in urban climate design. The temperature near the surface in a park is determined by the energy exchanges between the surface and the air above and it is therefore necessary to understand the surface energy balance of parks to intelligently manage their thermal microclimate. The objectives of this work were to study how the energy balances differ between different surfaces inside parks and in their built-up surroundings and to relate the surface energy balances to temperature differences.

Measurements were conducted during three clear summer days in the park Humlegården located in central Stockholm. The measuring instruments were mounted on a cart, which was transported from observation site to observation site. The observation sites represented typical surfaces found in an urban park and its surroundings: one shaded and one open grass surface, one open and one shaded gravel surface and two paved surfaces representing streets running in the north-south and east-west directions respectively. The energy fluxes were calculated using air and surface temperatures, wind speed, air humidity and net radiation data.

The most pronounced differences between the shaded and open surfaces in the park was that the shaded surfaces in general had smaller energy fluxes during daytime and that they had a downward directed sensible heat flux while the open surfaces had an upward directed sensible heat flux during the day. The most significant difference between the grass and the gravel surfaces in the park was that the grass surfaces had a bigger downward directed latent heat flux during the night and a smaller ground heat flux during both day and night. The largest differences between the surfaces inside the park and those in its built-up vicinities were that the paved surfaces had a larger upward directed sensible and ground heat flux during the night than the other surfaces. During the day the north-south directed paved site had a downward directed ground heat flux that was much larger than the ground heat flux for the other sites.

The coolest site during the night was the non-shaded grass surface, which was the only site with a downward directed sensible heat flux during the night. Compared to the other nonshaded sites the open grass surface had a much smaller ground heat flux. Warmest sites during the night were the paved surfaces, which had a larger upward directed sensible and ground heat flux than the other surfaces. At the built-up sites the walls also contributed with sensible heat flux, i.e. the total sensible heat flux in the built-up area was larger than what comes from the street surface only. During the day the shaded surfaces in the park were the coolest sites. The shaded surfaces had less net radiation compared to the other non-shaded surfaces and were the only sites that had a downward directed sensible heat flux.

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Zonato, Andrea. „Evaluating the urban heat island for cities of Emilia-Romagna region through numerical simulations“. Master's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/10913/.

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Lo scopo di questo studio è la comprensione della dinamica dello strato limite urbano per città dell’Emilia Romagna tramite simulazioni numeriche. In particolare, l’attenzione è posta sull’ effetto isola di calore, ovvero sulla differenza di temperatura dell’aria in prossimità del suolo fra zone rurali e urbane dovuta all’urbanizzazione. Le simulazioni sono state effettuate con il modello alla mesoscala "Weather Research and Forecasting" (WRF), accoppiato con le parametrizzazioni urbane "Building Effect Parametrization" (BEP) e "Building Energy Model" (BEM), che agiscono a vari livelli verticali urbani. Il periodo di studio riguarda sei giorni caldi e senza copertura nuvolosa durante un periodo di heat wave dell’anno 2015. La copertura urbana è stata definita con il "World Urban Databes and Access Portal Tools" (WUDAPT), un metodo che permette di classificare le aree urbane in dieci "urban climate zones" (UCZ), attraverso l’uso combinato di immagini satellitari e "training areas" manualmente definite con il software Google Earth. Sono state svolte diverse simulazioni a domini innestati, con risoluzione per il dominio più piccolo di 500 m, centrato sulla città di Bologna. Le differenze fra le simulazioni riguardano la presenza o l’assenza delle strutture urbane, il metodo di innesto e tipo di vegetazione rurale. Inoltre, è stato valutato l’effetto dovuto alla presenza di pannelli fotovoltaici sopra i tetti di ogni edificio e le variazioni che i pannelli esercitano sullo strato limite urbano. Per verificare la bontà del modello, i dati provenienti dalle simulazioni sono stati confrontati con misure provenienti da 41 stazioni all’interno dell’area di studio. Le variabili confrontate sono: temperatura, umidità relativa, velocità e direzione del vento. Le simulazioni sono in accordo con i dati osservativi e riescono a riprodurre l’effetto isola di calore: la differenza di temperatura fra città e zone rurali circostanti è nulla durante il giorno; al contrario, durante la notte l’isola di calore è presente, e in media raggiunge il massimo valore di 4°C alle 1:00. La presenza dei pannelli fotovoltaici abbassa la temperatura a 2 metri dell’aria al massimo di 0.8°C durante la notte, e l’altezza dello strato limite urbano dell’ordine 200mrispetto al caso senza pannelli. I risultati mostrano come l’uso di pannelli fotovoltaici all’interno del contesto urbano ha molteplici benefici: infatti, i pannelli fotovoltaici riescono a ridurre la temperatura durante un periodo di heat wave, e allo stesso tempo possono parzialmente sopperire all’alto consumo energetico, con una conseguente riduzione del consumo di combustibili fossili.

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Stewart, Iain Douglas. „The spatial and temporal dynamics of the urban heat island effect in Regina, Saskatchewan“. Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0017/MQ30560.pdf.

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Golden, Jay S. „Engineering for sustainable development : an examination of the urban heat island and its mitigation“. Thesis, University of Cambridge, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.445579.

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Huidong, Li [Verfasser]. „Urban Heat Island and its Influencing Mechanism In the City of Berlin / Li Huidong“. Berlin : Freie Universität Berlin, 2018. http://d-nb.info/1176639722/34.

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LI, YUXI. „Capstone Poster:-Singapore’s Building Greenery: A Strategy to Respond to Urban Heat Island Effect“. The University of Arizona, 2016. http://hdl.handle.net/10150/609229.

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Sustainable Built Environments Senior Capstone Project
Climate is an important factor for regional planners whenever they make decisions that concern the future shape and functions of a city. The purpose of this study is to analyze the effects of green infrastructure as a strategy to alleviate urban heat island effect in coastal cities. Taking Singapore as an example, the tropical climate of this country makes it hot and humid throughout the year. Therefore, the main climate issue of Singapore is the urban heat island effect, which raises temperatures in urban areas as opposed to surrounding rural ones. Regional planning authorities in Singapore have taken this climate factor into consideration making this city a great example for my topic.

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Ridha, Suaad. „Urban heat Island mitigation strategies in an arid climate. In outdoor thermal comfort reacheable“. Thesis, Toulouse, INSA, 2017. http://www.theses.fr/2017ISAT0006/document.

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De nombreuses études au cours des dernières décennies ont porté sur l'effet l’îlot de chaleur urbain (ICU). Les efforts initiaux visant à comprendre les facteurs qui influent sur l’ICU ont contribué à la mise en place de solutions et de stratégies d'atténuation adaptées. Les stratégies d'atténuation comprennent généralement l'augmentation de l'albédo urbain (réflectivité au rayonnement solaire) et l'évapotranspiration. Les augmentations d'albedo sont obtenues grâce à des technologies de toiture et de pavage ayant un albédo élevé. Une augmentation de l'évapotranspiration est obtenue par une combinaison de la diminution de la fraction de surfaces imperméables et la plantation de végétation dans les zones urbaines. Le confort thermique extérieur est défini à partir d’indices prenant en compte différents paramètres physiques et traduit la perception et la satisfaction des piétons. Ce confort est très difficile à obtenir en climat chaud et aride. Par conséquent, le travail présenté dans ce document met l'accent sur les méthodes appropriées pour réduire l’ICU et ainsi améliorer le confort thermique en plein air des piétons. Jusqu’à présent, peu de recherches ont été menées sur le confort thermique extérieur dans un climat chaud et aride. Les études sur l'atténuation de l'ICU et le confort thermique extérieur sont pratiquement inexistantes pour la ville de Bagdad. Bagdad a un tissu urbain complexe avec des constructions modernes, des maisons traditionnelles et des éléments caractéristiques du patrimoine local. Le climat en été est chaud, et les mois d'été sont considérés comme la plus longue saison avec près de 7 mois de l'année. Dans un premier temps, cette étude se concentre sur l'étude des stratégies d'atténuation à envisager afin d’évaluer comment le confort des piétons est affecté par les choix de conception des constructions, en comparant un quartier traditionnel à un quartier moderne. L’étude envisage ensuite la façon dont la végétation et les ombrages contribuent à réduire l'effet de l'ICU et à améliorer le confort thermique extérieur. Quatre scénarios différents sont élaborés pour évaluer le rôle d’éléments végétaux tels que les arbres, l'herbe et les différents modèles d'ombrage. L'évaluation a été effectuée le jour le plus chaud de l'été, la température radiante moyenne, l'humidité spécifique, la température de l'air et les distributions de la vitesse du vent ont été analysées à l'aide du logiciel ENVI-met. Le confort thermique est ensuite évalué à l'aide des indices thermiques de la température équivalente physiologique PET et du PMV étendu aux ambiances extérieures. En outre, une proposition de solution est abordée afin d’étudier son impact sur le confort thermique pour la journée la plus chaude (situation extrême) et une journée typique d’été. Les résultats ont révélé une amélioration du confort thermique dans la journée typique d’été. L'étude montre comment les facteurs urbains tels que le rapport d'aspect, la couverture végétale, les ombres et la géométrie du quartier sont des éléments cruciaux que les urbanistes et les municipalités doivent prendre en compte, en particulier pour les nouveaux aménagements urbains dans un climat chaud et aride. Une proposition d’aménagement global pour atténuer les ICU dans le cas d’un nouveau quartier sous climat aride, est détaillée en fin de mémoire
Numerous studies over the past several decades focused on the effect of the Urban Heat Island. Initial efforts on understanding the factors affecting UHI contributed to proceed the appropriate solutions and mitigation strategies. Mitigation strategies comprise increase both urban albedo (reflectivity to solar radiation), and evapotranspiration. Albedo increases are obtained through high albedo roofing and paving technologies. An increase in evapotranspiration is achieved through a combination of decreasing the fraction of impervious surfaces and planting vegetation in urban areas. The outdoor thermal comfort is influenced by the perception and satisfaction of the pedestrians, especially in hot and arid climates. Consequently, this work focuses on the appropriate methods for reducing the Urban Heat Island and thus to enhance the pedestrians outdoor thermal comfort. However, there is limited research conducted on the outdoor thermal comfort in hot and arid climate. The studies on the mitigation the Urban Heat Island and the outdoor thermal comfort are almost non-existent for Baghdad city. Baghdad has a complex urban fabric with modern design constructions buildings, traditional and heritage houses. The climate in summer is hot, and summer months are considered the longest season with nearly 7 months of the year. This study focuses on investigating possible mitigation strategies to ensure how pedestrian comfort is affected by the constructions design choices comparing a traditional district to a modern one, and on how vegetation and shading patterns contribute to reducing the effect of UHI and improving the outdoor thermal comfort. Four different scenarios are designed to assess the role of vegetation elements such as trees, grass, and different shading patterns. The evaluation was performed on the hottest day in summer, the mean radiant temperature, specific humidity, air temperature, and wind speed distributions have been analyzed using ENVI-met software. Thermal comfort is assessed using the thermal indices the Physiological Equivalent Temperature PET and the Predicted Mean Vote PMV. Also, a proposal model is designed to evaluate the thermal comfort on the hottest day and the typical day in summer. The results revealed an improvement on thermal comfort in the typical day in summer. The study shows how the urban factors such as the aspect ratio, vegetation cover, shadings, and geometry of the canyon are crucial elements that urban planners and municipalities have to take into account, especially for new urban developments in hot, arid climate

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Deilami, Kaveh. „Modelling the urban heat island intensities of alternative urban growth management policies in Brisbane“. Thesis, Queensland University of Technology, 2017. https://eprints.qut.edu.au/107656/1/Kaveh_Deilami_Thesis.pdf.

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When urban areas experience higher temperature than their surrounding rural areas, this phenomenon is called the urban heat island (UHI) effect. UHI contributes to global warming. Urban planning policy plays a significant role in controlling the UHI. This study examines the UHI effects of urban planning policy scenarios for Brisbane, including: a) business as usual; b) transit oriented development; c) infill development; d) motorway oriented development; and e) sprawl development. The findings show Infill development will be effective but will generate pockets of extreme UHI. Sprawl development will generate a moderate UHI effect but will be distributed throughout the city.

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Plank, Jack R. „Nuclear Thermal Propulsion Cool-Down Phase Optimization Through Quasi-Steady Computational Analysis, and the Effect of Auxiliary Heat Removal Systems“. The Ohio State University, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=osu1618934609976051.

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Dhami, Ishwar. „Urban tree phenology a comparative study between New York City and Ithaca, New York /“. Morgantown, W. Va. : [West Virginia University Libraries], 2008. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=5841.

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Thesis (M.S.)--West Virginia University, 2008.
Title from document title page. Document formatted into pages; contains vii, 49 p. : ill. (some col.), col. maps. Includes abstract. Includes bibliographical references (p. 37-45).

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Suen, Kwun-chiu, und 孫冠超. „A study of urban heat island effect using ground-level stationary observation stations in Hong Kong“. Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2013. http://hdl.handle.net/10722/194573.

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The Urban Heat Island (UHI) is a phenomenon in which the urban temperature is higher than that of the non-urban areas. Previous studies from other countries showed that an UHI phenomenon exists in urbanized cities. In Hong Kong, instead of only few study using fixed stationary stations on UHI analysis, past effort have been concentrated on using traverse and remote sensing method to study the UHI. This dissertation therefore describes the annual, seasonal and diurnal UHI variability in Hong Kong based on hourly data of temperatures, wind speed and relative humidity from five selected fixed stations at urban and non-urban areas over the period 2001-2011. UHI intensity is calculated by the temperature difference between the urban and non-urban areas excluding the global warming factors and micro-climatic effects. The results showed that, although there is no significant increasing and decreasing trend in annual UHI variation, the maximum annual UHI intensity is increasing and the nocturnal UHI is proved significantly higher than that its daytime counterpart. The seasonal UHI variation is higher in summer or autumn and winter depends on the choice of non-urban stations due to different geographic settings and land use. The diurnal UHI variation revealed that the strongest UHI intensity was observed in late afternoon or early morning while the weakest one occurred in afternoon. Among the study groups, Hong Kong International Airport experiences the highest UHI intensity. It is probably due to the geographical settings, unique land use and significant anthropogenic heat. On the other hand, in using Ta Kwu Ling as non-urban stations, the wind speed showed a significant negative correlation with UHI intensity while the relative humidity showed a positive one in diurnal UHI variation. The results of the study indicated that the choice of non-urban station poses a significant impact to the UHI intensity calculation especially in seasonal and diurnal variations. Further study on choosing representative non-urban station for UHI intensity calculation is recommended.
published_or_final_version
Environmental Management
Master
Master of Science in Environmental Management

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Russ, Jennifer Lynn. „a garden in the sky“. Thesis, Virginia Tech, 2004. http://hdl.handle.net/10919/9924.

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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

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BELL, JULIANNE. „Characteristics of the Urban Heat Island in Greater Cincinnati, Ohio: June 25, 2002 to June 24, 2003“. University of Cincinnati / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1085763113.

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Higginbotham, Gerald Ernest. „Influence of protein level and degradability on performance of lactating cows during hot and cool environmental temperatures“. Diss., The University of Arizona, 1987. http://hdl.handle.net/10150/184265.

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One hundred and twenty lactating Holstein cows in mid-lactation were offered diets varying in protein level and degradability at two locations during hot and moderate weather. Treatments were: (1) High protein (19%), high degradability (65%); (2) High protein (19%), medium degradability (40%); (3) Medium protein (15.5%), high degradability (65%); (4) Medium protein (15.5%), medium degradability (40%). Diets were individually fed during hot weather at the University of Arizona Dairy Farm and contained 38.4% alfalfa hay, 12.4% cottonseed hulls, 9.8% whole cottonseed, and 39.4% concentrate (dry matter). Diets were group fed during moderate weather at the Brigham Young University Dairy Farm, Provo, Ut, and contained 31.3% corn silage, 14% alfalfa haylage, 9.4% whole cottonseed and 45.3% concentrate (dry matter). Average daily ambient temperatures were 35.1°C for hot and 26.8°C for moderate weather locations. Fat-corrected milk (3.5%, 2 x milkings) and milk persistency were lower for treatment 1 than other treatments. For the respective treatments during hot weather means were: 23.4, 26.6, 28.5, 28.4 kg/d; 83.2, 91.2, 90.9, 90.3%; and for moderate weather means were: (3 x milkings): 34.7, 31.8, 32.2, 32.4 kg/d; 97.0, 93.4, 92.1, 90.3%. Dry matter intakes during hot weather were 21.5, 21.9, 23.3, and 23.1 kg/d. Respiration rate and rectal temperature during hot weather were: 90.1, 87.9, 90.9, 94.7 counts/min; 39.0, 39.3, 39.3, 39.5°C and for moderate weather: 61.2, 58.2, 55.5, 67.4 counts/min; 38.8, 38.6, 38.7, 38.8°C. Serum T₃,T₄ and cortisol were generally unaffected by treatment, but were depressed during hot weather. Serum glucose was not significantly affected by treatments at either environmental locations. Animals consumed more water with highly degradable protein diets at each location along with consuming more water during thermal stress. These data show that 3.5% fat-corrected milk and milk persistency are significantly affected (P <.01; P <.025) by rations high in protein of high degradability during heat stress.

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