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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

Reproductive Timing of Passerines in Urbanizing Landscapes

Shustack, Daniel P. 10 September 2008 (has links)
No description available.
132

Causal relationship between Air Quality (AQ) and the Urban Heat Island (UHI)

Ereminaite, Marija, Jayasinghe, Yasas January 2024 (has links)
This study critically examines the (UHI) effect in urban and suburban neighbourhoods of Quito, Ecuador, over a 19-year period, focusing on the interplay between atmospheric pollution and urban/ suburban temperature. Utilizing Empirical Dynamic Modeling(EDM) and Convergent Cross-Mapping (CCM), this study dives into the nonlinear dynamics of environmental factors, a method that traditional linear models fail to address effectively.The results unveil a consistent and strong positive correlation across various neighbourhoods, with temperature fluctuations indicating a typical UHI effect. This is most noticeable in urbanized areas where the temperature is significantly higher due to dense infrastructure and reduced greenery, a pattern that diminishes as one moves towards the outskirts. Specifically, pollutants like PM2.5 exhibit a non-uniform positive correlation, suggesting their collective increase or decrease across different regions, whereas CO shows a very slight and inconsistent inverse relationship across locations. The causal analysis further substantiates a significant interaction between PM2.5 concentrations and temperature, with the data revealing a reciprocal predictive capacity between these variables. The CCM analysis, through its graphical representation of predictive skills, confirms the causal effect of PM2.5 on urban temperature, marking an essential contribution to understanding the UHI effect and its implications for urban environmental dynamics. This study provides a comprehensive overview of the UHI phenomenon, highlighting the intricate relationship between urbanization, atmospheric pollution, and climate. The findings emphasize the necessity for urban planning and policy to consider these complex interactions to mitigate the effects of climate change on urban environments.
133

Främja resiliens i den svenska stadsplaneringen mot urbana värmeöar : En fallstudie av Gävle, Sundsvall och Uppsala stad

Reuithe, Karin, von Friesendorff, Filip January 2024 (has links)
Klimatförändringarnas påverkan på stadsmiljöer blir alltmer påtagligt med ökande frekvenser av extrema väderfenomen, vilket kräver resilienta städer med förmågan att anpassas till framtida störningar. Urbaniseringen förtätar städerna och leder till mer hårdgjord mark och minskad vegetation som kan resultera i fenomenet urbana värmeöar. Fenomenet koncentrerar och förlänger värmen i städer, vilket hotarmänniskors hälsa, särskilt under extrema värmeböljor. Värmeöar är väldokumenterade globalt men är en förbisedd fråga i Sverige. Examensarbetets syfte var därför att öka förståelsen kring värmeöar för svenska kommuner och myndigheter med exempel från städerna Gävle, Sundsvall och Uppsala. Målen var att föreslå resilienta planeringsåtgärder som både kan förbättra det pågående arbetet mot värmeöar samt nya inslag från internationell forskning.Studiens metoder var litteraturstudie, dokumentstudie av översiktsplaner (ÖP) samtintervjuer. En spatial multikriterieanalys (MKA) användes för att skapa farokartor av var värmeöar kan uppstå. Kriterier valdes genom litteratur, viktades med analytisk hierarkiprocess samt genomgick en känslighetsanalys. Farokartorna valideradessedan med Myndigheten för samhällsskydd och beredskaps (MSB) värmekartering. Resultaten visade att värmeöar behandlades på en övergripande nivå i ÖP. Varierade kunskaper om fenomenet framkom av respondenter från både kommuner och myndigheter. Flera utmaningar, möjligheter och planeringsåtgärder identifierades iarbetet mot värmeöar. Resiliens framhölls som ett nyckelkoncept i stadsplaneringen för att beakta olika klimatrisker där värmeöar är ett exempel. Litteraturstudien gav förslag på resilienta planeringsåtgärder i arbetet mot värmeöar som kan användas i svensk stadsplanering, vilka sedan sammanställdes. För att skapa resilienta städer krävs både reduceringsåtgärder (minska den byggda miljöns påverkan på stadsvärme)samt hanteringsåtgärder (förebyggande arbeten för att minska människors värmeexponering).  Farokartorna visade att värmeöar framför allt kan uppstå i bostads-, handels- och industriområden. MKA som metod för kartläggning av värmeöar överensstämdedelvis med marktemperaturer från MSB:s värmekartering. Slutsatsen av studien var att värmeöar behöver uppmärksammas mer i den svenska stadsplaneringen. Utmaningarna inkluderade att inkorporera värmefrågor i befintlig bebyggelse, medan möjligheterna fanns i fler planeringsunderlag och detaljerade kartläggningar. Främjandet av resiliens, särskilt genom reducerings- och hanteringsåtgärder,behöver utvecklas i Sverige för att stärka planeringsarbetet mot värmeöar i både nutida och framtida stadsplanering. / The impact of climate change on urban environments is becoming increasinglyapparent with higher frequencies of extreme weather phenomena, which requires resilient cities with the ability to adapt to future disturbances. Urbanization densifies cities and leads to more hard surfaces and reduced vegetation which can result in urban heat islands (UHI). This phenomenon concentrates and prolongs heat in citieswhich threatens human health, especially during extreme heat waves. UHI are well documented globally but are an overlooked issue in Sweden.  The aim of the study was therefore to increase the understanding of UHI for Swedish municipalities and authorities with examples from the cities of Gävle, Sundsvall and Uppsala. The goals were to propose resilient planning measures that can both improve the ongoing work against UHI as well as new elements from international research. The study's methods were a literature study, a document study of comprehensive plans (översiktsplan) and interviews. A spatial multicriteriaanalysis (MCA) was used to create hazard maps of where UHI can occur. Criteria were selected through literature, weighted using analytic hierarchy process and underwent a sensitivity analysis. The hazard maps were validated with the Swedish Civil Contingencies Agency’s (MSB) heat mapping. The results showed that UHI were treated at an overall level in comprehensiveplans. Varied knowledge about the phenomenon emerged from respondents from both municipalities and authorities. Several challenges, opportunities and planning measures were identified in the work against UHI. Resilience was highlighted as a key concept in urban planning to consider various climate risks where UHI are an example. The literature study provided suggestions for resilient planning measures in the work against UHI that can be used in Swedish urban planning, which were then compiled. To create resilient cities, both reduction measures (reducing the built environment's impact on urban heat) and management measures (preventive work to reduce people's heat exposure) are required.  The hazard maps showed that UHI mainly occur in residential, commercial and industrial areas. MCA as a method for UHI mapping partially matches ground temperatures from MSB's heat mapping. The conclusion of the study was that UHIneed more attention in Swedish urban planning. Challenges included incorporating heating issues into existing buildings, while the opportunities were in more planning documents and detailed mapping. The promotion of resilience, especially through reduction and management measures, needs to be developed in Sweden to strengthen the planning against UHI in both present-day and future urban planning.
134

Sustainable urban agriculture and forestation : the edible connected city

Durant, Valerie A. 12 July 2013 (has links)
Current global agricultural practices are recognized as unsustainable. The increase in overall human population as well as the global trend of rural to urban migration, partially as a result of historically and continual unsustainable agricultural practices, exacerbates the vicious cycle of poverty and hunger in developing countries. Furthermore, cities and regions in developed countries practice unsustainable food production, distribution and consumption patterns, and as a result, exceed their global ecological footprint (Rees 2009). Consequently, the world is facing a global food (FAO 2009) and water crisis (UN Sick Water 2010). Cities and Regions must learn to feed themselves to address local food insecurity as well as protect from the climate effects of increased urbanization, including the Urban Heat Island effect (UHIe) by optimizing and fully integrating the local ecosystem services of food, water and forest within a tightly woven compact urban form through the implementation of strategic urban and regional food system planning. Cities can mitigate climate change and reduce the UHIe, by implementing sustainable intensive urban agriculture approaches through policy and zoning interventions that include concepts such as intensively productive urban agriculture that includes green roofs, vertical farming and greenways as continuously productive and edible urban landscapes, referred to in this paper as continuously productive urban agriculture and forestation (CPUAF) in the private and public realm. A highly participative, adaptive systems approach is explored as the key to sustainability within an economic world order that included corporate social responsibility and social enterprise as the foundation for the integration of multiple synergies. An increasing body of evidence often links urban forestation with urban greenery initiatives, as a carbon sink to reduce UHI effects, to reduce GHG emissions and as a tool for urban beautification and place making (ISDR: 2009,109). Urban agriculture, through the production of local food is increasingly recognized as a means to reduce fossil fuel emissions by reducing transportation and production outputs, to provide a secure local food source, enhance biodiversity and educate the public regarding food source while fostering a sense of community, environmental awareness and stewardship. This thesis explores the links between intensive urban agriculture and forestation, and the relationship between climate change, and the UHI’s as an adaptation and mitigation process in global cities, implemented as a interconnected, integrated, holistic urban management approach that has a further benefit of providing food security and a sustainable and local urban food source. / Dissertation (MTRP)--University of Pretoria, 2012. / Town and Regional Planning / unrestricted
135

Identifying enhanced urban heat island convection areas for Indianapolis, Indiana using space-borne thermal remote sensing methods

Boyd, Kelly D. 02 April 2015 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Heat is one of the most important factors in our atmosphere for precipitation (thunderstorm) formation. Thermal energy from local urban land-cover is also a common source of heat in the lower atmosphere. This phenomenon is known as the urban heat island effect (UHI) and is identified as a substantial cause to a changing climate in surface weather modification. The proceeding study investigates this connection between the UHI and surface weather using remote sensing platforms A ten-year analysis of the Indianapolis UHI and thunderstorms were studied from the summer months of May, June, July, August and September (MJJAS) from 2002 until 2011. LANDSAT space borne satellite technology and land-surface based weather radar technology was used in this analysis for thunderstorm investigation. Precipitation areas identified from land-based NEXRAD WSR-88D technology were used to identify convection from non-synoptic forcing and non-normal surface diurnal heating scenarios. Only convection appearing from the UHI were studied and analyzed. Results showed twenty-one events over eighteen days with the year 2005 and 2011 having the largest frequency of events. The month of August had the largest concentration with seven events during the late afternoon hours. UHI results showed July had the largest heat island magnitude with April and September having the lowest magnitude in UHI temperatures. Three events of the twenty-one storm paths did not had a significant mean temperature difference in the heat island below the storm reflectivity. The nineteen storm paths that were significant had a warmer area underneath storm path development by an average 6.2°C than surrounding areas. UHI initiation points showed twelve of the twenty-one events having statistically significant differences between 2 km initiation areas and the rest of the study areas. Land-cover results showed low intensity developed areas had the most land-cover type (48%) in the 2km initiation buffer regions.
136

Processus d'acquisition de nouvelles connaissances en urbanisme : le cas de l'îlot de chaleur urbain

Perreault, Simon 08 1900 (has links)
Dans le contexte du changement climatique, la chaleur est, depuis le début des années 2000, une préoccupation grandissante, d’abord en tant qu’enjeu sanitaire puis comme problématique affectant la qualité de vie des citoyens. Au Québec, le concept d’îlot de chaleur urbain, issu de la climatologie urbaine, a graduellement émergé dans le discours des autorités et de certains acteurs de l’aménagement. Or, on constate l’existence d’un certain décalage entre les connaissances scientifiques et l’interprétation qu’en font les urbanistes. Dans le cadre de ce mémoire, on a tenté d’identifier les facteurs explicatifs de ce décalage en s’intéressant au processus d’acquisition des connaissances des urbanistes québécois. Par le biais d’entretiens réalisés auprès des principaux acteurs ayant contribué à l’émergence de l’ICU au Québec, on a été en mesure d’identifier les éléments ayant entraîné certaines distorsions des connaissances. L’absence d’interdisciplinarité entre la climatologie urbaine et l’urbanisme tout au long du processus d’acquisition des connaissances ainsi qu’une interprétation tronquée de la carte des températures de surface expliquent principalement la nature du décalage observé. / In the context of current debates on climate change, heat has become a growing concern since the early 2000s, as it impacts people’s health and quality of life. As an element of urban climatology, the concept of urban heat islands emerged as a standard reference used by a number of Quebec scholars and practitioners in environmental management. However, there appears to be certain discrepancies between our current scientific knowledge and its interpretation by urban planners. The objective of this thesis is to better understand the factors that explain this discrepancy, through a study of knowledge acquisition among Quebec urban planners. Using a series of interviews with key actors in the emerging field of UHI’s in Quebec, it has been possible to identify the elements that caused distortions in knowledge transfer. Generally, the lack of interdisciplinarity in the areas of urban climatology and planning throughout the knowledge acquisition process, as well as a partial understanding of the surface temperature maps, help explain the nature of these discrepancies.
137

Contribution à l'analyse de la prise en compte du climat urbain dans les différents moyens d'intervention sur la ville / Contribution to the analysis of various means to take into account urban climate in urban planning

Colombert, Morgane 08 December 2008 (has links)
Le milieu urbain est à l'origine de processus radiatifs, thermiques, dynamiques et hydriques qui modifient le climat de la ville. La couche superficielle du sol, avec la présence plus ou moins importante de surfaces végétales ou d’eau, les activités humaines qui induisent des rejets de chaleur et de polluants, et la structure urbaine, avec des matériaux de construction et une certaine morphologie du cadre bâti, sont les principaux facteurs de cette modification. Le bilan d'énergie thermique permet d'appréhender la majorité des perturbations générées par la ville. A l'aide du schéma Town Energy Balance, développé par Météo-France pour paramétrer les échanges en énergie et en eau entre les surfaces bâties et l'atmosphère, nous avons effectué des tests de sensibilité du bilan d'énergie à différents facteurs. Ces facteurs appartiennent à cinq domaines d'actions : le bâtiment, l'espace public, l'organisation urbaine, les activités industrielles et les transports. Nos différentes simulations ont permis de confirmer le rôle prédominant des paramètres radiatifs dans le bilan d'énergie de la ville en été. Durant l'hiver, ce sont d’autres paramètres thermiques (isolation) qui ont la plus grande influence. Les collectivités territoriales françaises ont à leur disposition plusieurs outils et moyens pour agir en faveur de leur environnement climatique et intégrer des facteurs influant sur le climat urbain : leurs domaines de compétence directe (voirie, bâtiments communaux, espaces verts, etc.), les documents stratégiques d'orientation (SCOT et PLU), les procédures d'aménagement (ZAC et lotissement), l'incitation et l'information de leurs citoyens et de leurs services (Agenda 21 local, Plan Climat Territorial, Approche Environnementale de l'Urbanisme). Elles ne peuvent cependant pas agir avec une liberté suffisante, compte tenu des limites contraignantes entre droit de l’urbanisme et droit de la construction et de l’habitat / Urbanization, with artificial surfaces replacing natural land, more anthropogenic heat and urban geometry, modifies the micro and meso scale climate. Such modifications do alter the radiative, thermal, moisture and aerodynamics properties of the urban environment. The study of energy balance could help understanding most of these changes. In this thesis, we used the urban surface exchange parameterization of Météo-France: Town Energy Balance, which computes water and energy exchanges between urban surfaces and atmosphere. In order to study the significance of different factors, we made a sensivity study. Factors are filed in five fields: building, public space, land use, industrial activities and transports. Our simulations showed that radiative parameters are the most influential during the summer. During winter, other thermal parameters (insulation) are the most influential. French local authorities could use several tools and means to act in favor of their climatic environment: their fields of direct jurisdiction (roads, parks, buildings which are owned by the community, etc.), guidance documents (SCOT and PLU), development procedures (urban development zone and building plotting), and incitement and pieces of information for their citizens and their agencies (local Agenda 21, Plan Climat, Approche Environnementale de l'Urbanisme). They can not work completely freely because of the boundary between urban planning law and building and dwelling law
138

A rela??o entre o fator de vis?o do c?u e a temperatura do ar em diferentes zonas clim?ticas locais / The relationship between the sky view factor and air temperature across different local climate zones

Soeira, Marcelo Rezende Cal?a 28 January 2019 (has links)
Submitted by SBI Biblioteca Digital (sbi.bibliotecadigital@puc-campinas.edu.br) on 2019-03-18T17:37:56Z No. of bitstreams: 1 MARCELO REZENDE CAL?A SOEIRA.pdf: 10669454 bytes, checksum: 0c817cd4715977e2f4677644509e8516 (MD5) / Made available in DSpace on 2019-03-18T17:37:56Z (GMT). No. of bitstreams: 1 MARCELO REZENDE CAL?A SOEIRA.pdf: 10669454 bytes, checksum: 0c817cd4715977e2f4677644509e8516 (MD5) Previous issue date: 2019-01-28 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The objective of this research was to estimate and compare the Sky View Factor (SVF) and Urban Heat Island Intensity (UHII) correlation across different Local Climate Zones (LCZs) situated in the city of Campinas, S?o Paulo, Brazil. The SVF consists of an non dimensional parameter which describes the ratio of visible sky from a given point in space. In the urban environment, SVF values are strongly related to buildings density and height. Also strongly related to the densification and verticalization of the urban tissue is the Urban Heat Island phenomenon, which is characterized by the elevation of air temperature in urban environments as a result of its impact on the surface energy balance. For this reason, research has been conducted in many countries to investigate the correlation between SVF and the UHII. To evaluate the effects of urban tissue composition on these correlations, however, systematic methods for detecting and reporting such composition are required. Employing the Local Climate Zones method, which classifies urban areas as climate zones according to their structural typology and surface cover, this research evaluated SVF-UHII correlation variations across different built up areas of the same city. Combining mobile measurements and stationary monitoring devices a map of the nocturnal UHII at the research site was obtained. According to seven parameters (H/W ratio; SVF; Built area; Permeable area; Impermeable area; Height of roughness elements; And roughness class), obtained by geoprocessing, eleven LCZs were identified at the site. Nocturnal UHII linear regressions were calculated for SVF values (point and 100m radius average values were used) at eight LCZs classes. At compact low, low-high, mid-low and high-mid rise LCZs (3, 31, 23 and 12), with SVF values between 0,20 and 0,45, the approximate air temperature increase ranged from 1,5 up to 2,2?C. At compact low and mid-low rise LCZs (3 and 23), with SVF values between 0,45 and 0,7, the approximate air temperature increase ranged from 0,7 up to 1,2?C. For sparsely built low rise LCZs (6), with SVF between 0,60 and 0,90, the approximate air temperature variation ranged from - 0,2 up to 0,0?C. From these results it was concluded that the correlation between SVF and UHII is influenced by the morphological and superficial composition of the urban tissue. Hence, to effectively utilize SVF in UHI mitigation strategies, these influences should be considered. / A presente pesquisa teve como objetivo estimar e comparar as correla??es entre o FVC e a varia??o da temperatura do ar encontradas em diferentes zonas clim?ticas situadas em um recorte da cidade de Campinas- SP. O fator de vis?o do c?u (FVC) ? um par?metro adimensional utilizado para descrever a propor??o de c?u vis?vel, em um determinado local, a partir do n?vel do solo. No ambiente urbano, seu valor est? fortemente relacionado ao grau de compacta??o e verticaliza??o da malha construtiva. Outro fen?meno relacionado ao grau de compacta??o e verticaliza??o da malha urbana ? o fen?meno da Ilha de Calor Urbana (ICU), caracterizado pela reten??o do calor absorvido no ambiente constru?do. Por este motivo, ? grande o n?mero de pesquisas que estudam a correla??o entre o FVC e o fen?meno da Ilha de Calor Urbana em diversas cidades do mundo. Atrav?s de m?todos sistem?ticos para o reconhecimento e documenta??o de heterogeneidades da malha urbana, como o m?todo das Zonas Clim?ticas Locais (LCZs), que classifica ?reas urbanas em zonas clim?ticas locais de acordo com sua tipologia construtiva e cobertura de superf?cies, tornou-se poss?vel avaliar a varia??o desta correla??o em um contexto intramunicipal. Atrav?s de campanhas de medi??es m?veis e de pontos fixos de monitoramento, a intensidade da ilha de calor urbana na ?rea de estudo foi avaliada. A ?rea de estudo foi classificada em onze LCZs de acordo com sete par?metros urban?sticos obtidos por geoprocessamento (rela??o altura-largura, FVC, ?rea edificada, ?rea imperme?vel, ?rea perme?vel, altura m?dia dos elementos de rugosidade e classe de rugosidade). Regress?es lineares foram estabelecidas entre a intensidade da ICU ?s 21:00 e valores de FVC (pontuais e m?dios para um raio de 100m) em ?reas de an?lise correspondentes a oito LCZs. Para valores de FVC entre 0,20 e 0,45, a eleva??o aproximada da temperatura do ar em LCZs de arranjo compacto e verticaliza??o baixa a m?dia-alta ? 1,5 a 2,2 ?C; para valores de FVC entre 0,45 e 0,7 em LCZs de arranjo compacto e verticaliza??o baixa e m?dia-baixa, a eleva??o aproximada da temperatura do ar foi de 0,7 a 1,5 ?C; e para valores de FVC entre 0,60 e 0,90 em LCZs de arranjo esparso e verticaliza??o baixa, a varia??o aproximada da temperatura do ar foi de 0,0 a -0,2 ?C. Assim, conclui-se que a influ?ncia do FVC na eleva??o da temperatura do ar em ?reas urbanizadas varia conforme a composi??o morfol?gica e superficial do tecido urbano. Para que o FVC seja utilizado efetivamente em estrat?gias de mitiga??o da ICU, essa rela??o deve ser considerada.
139

On the modelling of solar radiation in urban environments – applications of geomatics and climatology towards climate action in Victoria

Krasowski, Christopher B. 04 October 2019 (has links)
Modelling solar radiation data at a high spatiotemporal resolution for an urban environment can inform many different applications related to climate action, such as urban agriculture, forest, building, and renewable energy studies. However, the complexity of urban form, vastness of city-wide coverage, and general dearth of climatological information pose unique challenges doing so. To address some climate action goals related to reducing building emissions in the City of Victoria, British Columbia, Canada, applied geomatics and climatology were used to model solar radiation data suitable for informing renewable energy feasibility studies, including photovoltaic system sizing, costing, carbon offsets, and financial payback. The research presents a comprehensive review of solar radiation attenuates, as well as methods of accounting for them, specifically in urban environments. A novel methodology is derived from the review and integrates existing models, data, and tools – those typically available to a local government. Using Light Detection and Ranging (LiDAR), a solar climatology, Esri’s ArcGIS Solar Analyst tool, and Python scripting, daily insolation (kWh/m2) maps are produced for the city of Victoria. Particular attention is paid to the derivation of daily diffuse fraction from atmospheric clearness indices, as well as LiDAR classification and generation of a Digital Surface Model (DSM). Novel and significant improvements in computation time are realized through parallel processing. Model results exhibit strong correlation with empirical data and support the use of Solar Analyst for urban solar assessments when great care is taken to accurately and consistently represent model inputs and outputs integrated in a methodological approach. / Graduate
140

La isla de calor urbana de superficie y sus factores condicionantes: El caso del área metropolitana de Santiago

Sarricolea Espinoza, Pablo 05 October 2012 (has links)
Se ha sintetizado la información de las temperaturas de emisión superficial obtenidas mediante 53 imágenes del satélite Terra MODIS, aplicando para ello promedios anuales y estacionales de las temperaturas estandarizadas, y reducción de las imágenes a factores complejos de los patrones espaciales usando Análisis de Componentes Principales (ACP); finalmente, se han realizado mapas de diferencias térmicas para conocer la intensidad de la isla de calor urbana de superficie (ICUs) estacional y anual. Los resultados muestran que la isla de calor tiende a localizar el máximo térmico en las comunas de Santiago, Providencia, Las Condes, Ñuñoa y Vitacura, conformando un núcleo cálido asociado a la mayor densidad construida; además, las comunas de Huechuraba y Quilicura conforman otro núcleo cálido, el que está asociado a viviendas de alto nivel de ingresos en el primer caso e industrias en el caso de Quilicura. El ACP revela cuatro patrones típicos, que explican el 90,6% de las situaciones, a saber: ICUs consolidada (44,5%), ICUs del piedmont y cuña de altos ingresos (22,3%), un tipo sin isla de calor urbana (20,2%) e ICUs más intensa al sur (3,6%). Finalmente, la intensidad de la isla de calor urbana de superficie es de mayor magnitud durante el otoño (7,4ºC), seguida de verano (5,9ºC), primavera (5,4ºC) e invierno (5,0ºC); incluso en verano y otoño supera los 7ºC en la zona oriente de la ciudad. De las situaciones sin isla de calor, se ha sugerido la hipótesis de efecto sumidero de calor o «urban heat sink», asociado a fuerte brisa de la Cordillera de Los Andes, que barre la ICUs y la desplaza al poniente de la ciudad, lo que en días de contaminación por material particulado (PM10) tendría efectos nocivos sobre la salud de la población de esa parte de la ciudad. Además, se modela la isla de calor urbana de superficie (ICUs) en función de una serie de variables geográficas y urbanas, con el propósito de plantear alternativas para la mitigación de los efectos negativos que las ICUs provocan a los habitantes de la ciudad de Santiago. Además, se entregan algunas directrices para una planificación territorial más sostenible. En total se utilizaron 42 mapas de isla de calor del año 2010, los cuales se generaron con imágenes satelitales Terra MODIS. Ellos fueron sintetizados en cinco cartografías, un mapa anual y cuatro correspondientes a las estaciones del año. Las variables explicativas para predecir la isla de calor fueron nueve: densidad de población y construida, elevación topográfica, NDVI, albedo, radiación solar y las distancias euclidianas al centro, la costa y los ríos y esteros. Los resultados de los modelos de regresión lineal múltiple por pasos indican coeficientes de determinación entre 47,39% y 80,08% (invierno y verano respectivamente). Las variables explicativas más influyentes son el albedo y el NDVI (relación negativa), y la densidad construida (relación positiva). Al modificar las variables que explican la ICUs se podría variar la intensidad de ella, por ejemplo: al aumentar de 10.000 m2 a 20.000 m2 construidos por hectárea la temperatura deberá aumentar entre 1ºC y 2ºC; implementando de áreas verdes un espacio sin vegetación, la isla de calor se verá reducida entre 1,2ºC y 5,5ºC; y al modificar el albedo de la ciudad desde un 10% a un 20% se consigue una reducción de la ICUs entre 1,1ºC y 2,7ºC.

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