abstract: The global increase in urbanization has raised questions about urban sustainability to which multiple research communities have entered. Those communities addressing interest in the urban heat island (UHI) effect and extreme temperatures include land system science, urban/landscape ecology, and urban climatology. General investigations of UHI have focused primarily on land surface and canopy layer air temperatures. The surface temperature is of prime importance to UHI studies because of its central rule in the surface energy balance, direct effects on air temperature, and outdoor thermal comfort. Focusing on the diurnal surface temperature variations in Phoenix, Arizona, especially on the cool (green space) island effect and the surface heat island effect, the dissertation develops three research papers that improve the integration among the abovementioned sub-fields. Specifically, these papers involve: (1) the quantification and modeling of the diurnal cooling benefits of green space; (2) the optimization of green space locations to reduce the surface heat island effect in daytime and nighttime; and, (3) an evaluation of the effects of vertical urban forms on land surface temperature using Google Street View. These works demonstrate that the pattern of new green spaces in central Phoenix could be optimized such that 96% of the maximum daytime and nighttime cooling benefits would be achieved, and that Google Street View data offers an alternative to other data, providing the vertical dimensions of land-cover for addressing surface temperature impacts, increasing the model accuracy over the use of horizontal land-cover data alone. Taken together, the dissertation points the way towards the integration of research directions to better understand the consequences of detailed land conditions on temperatures in urban areas, providing insights for urban designs to alleviate these extremes. / Dissertation/Thesis / Doctoral Dissertation Geography 2018

abstract: This dissertation explores vulnerability to extreme heat hazards in the Maricopa County, Arizona metropolitan region. By engaging an interdisciplinary approach, I uncover the epidemiological, historical-geographical, and mitigation dimensions of human vulnerability to extreme heat in a rapidly urbanizing region characterized by an intense urban heat island and summertime heat waves. I first frame the overall research within global climate change and hazards vulnerability research literature, and then present three case studies. I conclude with a synthesis of the findings and lessons learned from my interdisciplinary approach using an urban political ecology framework. In the first case study I construct and map a predictive index of sensitivity to heat health risks for neighborhoods, compare predicted neighborhood sensitivity to heat-related hospitalization rates, and estimate relative risk of hospitalizations for neighborhoods. In the second case study, I unpack the history and geography of land use/land cover change, urban development and marginalization of minorities that created the metropolitan region's urban heat island and consequently, the present conditions of extreme heat exposure and vulnerability in the urban core. The third study uses computational microclimate modeling to evaluate the potential of a vegetation-based intervention for mitigating extreme heat in an urban core neighborhood. Several findings relevant to extreme heat vulnerability emerge from the case studies. First, two main socio-demographic groups are found to be at higher risk for heat illness: low-income minorities in sparsely-vegetated neighborhoods in the urban core, and the elderly and socially-isolated in the expansive suburban fringe of Maricopa County. The second case study reveals that current conditions of heat exposure in the region's urban heat island are the legacy of historical marginalization of minorities and large-scale land-use/land cover transformations of natural desert land covers into heat-retaining urban surfaces of the built environment. Third, summertime air temperature reductions in the range 0.9-1.9 °C and of up to 8.4 °C in surface temperatures in the urban core can be achieved through desert-adapted canopied vegetation, suggesting that, at the microscale, the urban heat island can be mitigated by creating vegetated park cool islands. A synthesis of the three case studies using the urban political ecology framework argues that climate changed-induced heat hazards in cities must be problematized within the socio-ecological transformations that produce and reproduce urban landscapes of risk. The interdisciplinary approach to heat hazards in this dissertation advances understanding of the social and ecological drivers of extreme heat by drawing on multiple theories and methods from sociology, urban and Marxist geography, microclimatology, spatial epidemiology, environmental history, political economy and urban political ecology. / Dissertation/Thesis / Ph.D. Environmental Social Science 2013

A modificação das condições iniciais do clima é conseqüência inerente da substituição da cobertura natural do solo pelo ambiente construído. Nesse processo, um dos mecanismos do sistema cidade-atmosfera mais afetado pela mudança do uso e da cobertura do solo é o campo térmico urbano. Assim, esta pesquisa objetivou estudar a configuração do campo térmico da cidade de São Carlos nas suas dimensões espaços-temporais, com vistas a conhecer a intensidade da ilha de calor urbano no período de verão, dentro de suas variações diurnas e das condições impostas pelos diferentes tipos de tempo habituais, com o aporte da abordagem dinâmica do clima. A análise da intensidade do campo térmico urbano foi feita a partir de registros de dados climáticos contínuos tomados em superfície por quatro estações automáticas instaladas em diferentes regiões da malha urbana. Os resultados obtidos denotaram que a maior intensidade da ilha de calor urbano, no período de verão, ocorreu na atuação da massa Tropical Atlântica sobre a região, cujo tipo de tempo habitual foi caracterizado por cenário atmosférico com predominância de céu claro, alta incidência de radiação solar direta e valores de temperatura do ar elevados com máxima diária acima da média das máximas indicadas pelas normais climatológicas. Sob essas condições, observou-se que as características do entorno construído exerceram maior influência no comportamento térmico urbano, na qual as diferenças térmicas entre diferentes regiões dentro da malha urbana de São Carlos foram superiores a \'5 GRAUS\' Celsius. Observou-se, ainda, que a maior expressão da ilha de calor urbano ocorreu após o pôr-do-sol, nos horários entre 21:30h e 22:00h. / The initial conditions of the climate are consequence of replacing the natural ground cover by the built environment. In this process, one of the most affected mechanics of the city-atmosphere system due to the change of use and land cover is the urban thermal field. Thus, this research aim to study the configuration of the thermal field of São Carlos in the spatial and temporal dimensions for understanding the intensity of urban heat island in the summer, taking into account its diurnal temperature variations and imposed conditions by different weather types, guided by the climate dynamics approach. The analysis of the intensity of urban thermal field is made from records of climatic data observed in solid ground for four automatic weather stations placed in different areas of the city. The obtained results denote that the highest intensity of urban heat island in summer occurs in the activity of Tropical Atlantic air mass over the region, where the habitual weather was clear skies with high incidence of direct solar radiation and values of air temperature with high daily maximum above the average of the levels indicated by the climate normals. Under these weather conditions, it is observed that the characteristics of the built environment have a greater influence on urban thermal behavior, in which the temperature variations between different regions within the urban area of San Carlos were above 5 Celsius \'DEGREES\'. It is also observed that the highest intensity of urban heat island occurred after sunset, at times between 21:30 and 22:00h.

A Região Metropolitana de São Paulo (RMSP) conta com mais de 20 milhões de habitantes em 7958 km², o que a caracteriza como uma megacidade. Este fato ocasiona o efeito de ilha de calor que pode resultar em interações complexas com circulações de mesoescala, tais como a brisa marítima, podendo influenciar nos padrões de circulação local e afetar diretamente o tempo e o clima da região. Dessa forma, através da modelagem numérica com o modelo de mesoescala WRF este trabalho se propôs a analisar e avaliar os possíveis efeitos da expansão da mancha urbana - passada e futura - na modificação destes padrões em duas estações do ano de 2007: inverno (18/08) e verão (07/03). Para isto introduziu-se diferentes manchas urbanas no modelo, supondo nenhuma urbanização, urbanização observada em 1952 e em 2007, bem como uma suposta urbanização prevista para o ano de 2030. O acoplamento de um modelo de dossel urbano junto ao WRF também foi avaliado, e os resultados mostraram que para o inverno a inclusão do mesmo se mostrou dispensável, enquanto para o verão as simulações em que o módulo esteve ativo se mostraram mais coerentes à realidade. Para as duas estações observou-se a influência da expansão da mancha urbana nos eventos de brisa marítima, sendo que quanto maior a área urbanizada maior o tempo de deslocamento da frente de brisa continente adentro, podendo a diferença chegar a 2 horas. Diferenças na temperatura também puderam ser vistas, principalmente à noite no período de inverno, de forma que algumas regiões chegaram a apresentar 6 °C a mais em 2007. Observou- se uma frente de umidade acompanhando a frente de brisa marítima e quanto maior a urbanização, menor a quantidade de umidade associada, chegando a uma redução de 22% durante o inverno e de 33% durante o verão. No inverno não foram observadas grandes diferenças na precipitação, enquanto que no verão foram encontradas diferenças significativas em praticamente todo o domínio de simulação, chegando a 50 mm em determinadas regiões (a mais ou a menos). Tais diferenças na precipitação não se mostraram lineares com a expansão da mancha urbana. Cortes verticais não evidenciaram circulações bem definidas associadas à ilha de calor, nem para o inverno nem para o verão, no entanto, claramente pôde-se observar a influência que a expansão urbana tem sobre os episódios de brisa marítima, em quaisquer das variáveis meteorológicas analisadas. / The Metropolitan Area of São Paulo (MASP) has over 20 million inhabitants over a 7958 km² area, which characterizes a megacity. This fact causes the heat island effect that can result in complex interactions with mesoscale circulations such as the sea breeze and can influence the local circulation and directly affect the weather and climate of the region. Therefore, through numerical modeling of the atmosphere using the WRF mesoscale model this work analyses and evaluates the possible effects of urban expansion - past and future on the modification of these patterns in two days representatives of the winter and summer (18/08 and 07/03, respectively). For that purpose we introduced different types of urban areas in the model, assuming no urbanization, using the urbanization observed in 1952 and 2007 as well as a hypothetical urbanization numerically predicted for the year of 2030. The coupling of an urban canopy model (UCM) along with WRF was also evaluated and the results showed that the inclusion of UCM proved to be unnecessary during wintertime. However, in the summer, the simulations where the module was activated were more consistent with reality. For the two seasons we observed the influence of urban expansion in the events of sea breeze, and the higher the urbanized area more increased was the travel time of the sea breeze front inland, being the time difference as high as 2 hours. Differences in temperature were also observed, especially at night in the winter, so that some regions were as high as 6 °C hotter in 2007. A moisture front accompanying the sea breeze front and the higher the urbanization the lower the amount of moisture associated, reaching a reduction of 22% during winter and 33% during the summer. During the winter no major differences were observed in precipitation, while in the summer significant differences were found almost over all simulation domain, reaching 50 mm in certain regions (positive or negative). Such differences in precipitation were not linear with the expansion of urban area. Vertical sections did not show well-defined circulations associated with urban heat island, neither for the winter nor for summer, however, we can clearly observe the influence that urban area extension has on episodes of sea breeze in any of the weather variables.

Eventos de brisa marítima (BM) são comuns na Região Metropolitana de São Paulo (RMSP). No verão, em particular, estão associados com tempestades, chuvas, rajadas de vento, granizo e descargas atmosféricas intensas na RMSP. Utilizou-se o método de OLIVEIRA e SILVA DIAS (1982) para identificar os eventos de BM. Todos os eventos de BM entre 2005 e 2008 foram analisados por meio de medições de superfície, altitude, radares meteorológicos, satélite e modelagem numérica da atmosfera. Em geral, a penetração da frente de BM na RMSP ocorre entre o meio e o fim da tarde com aumento da temperatura do ponto de orvalho. Ainda, o ambiente urbano mais aquecido tende a intensificar as tempestades que podem produzir enchentes, alagamentos, queda de árvores, entre outros impactos socioeconômicos muito significativos. A partição anual pluviométrica devido a BM foi estimado com o radar meteorológico de São Paulo. Os resultados indicam um núcleo de máxima precipitação acumulada com pico de 600 mm sobre a RMSP, muito maior que no entorno dessa. A modelagem com o ARPS permitiu simular condições médias espaciais em baixos, médios e altos níveis de diversas variáveis dos eventos analisados. As simulações de controle e específicas com ARPS sugerem um impacto significativo da cobertura do solo na distribuição espacial da precipitação. As análises foram complementadas com medições do radar meteorológico MXPOL e demonstram a importância desse tipo de sensoriamento remoto na detecção e previsão a curtíssimo prazo da penetração de BM, com alta resolução espaço-temporal. / Sea breeze events (SB) are common in Metropolitan area at São Paulo (MASP). Particularly, in the summer, SB triggers over MASP deep convection, heavy rainfall, wind gusts, hail and lightning. OLIVEIRA and SILVA DIAS (1982) method was used to identify the SB events. SB events between 2005 and 2008 were analysed by means of surface and upper air measurements, weather radar, satellite and numerical modelling. In general, the SB front penetrates in MASP between midafternoon and evening increasing dew point. Moreover, the warmer urban environment tends to intensify storms that produce flooding, falling trees, among other large socioeconomic impacts. The annual rainfall partition due to SB was estimated using the São Paulo weather radar. The results indicate a core of maximum rainfall accumulation of 600 mm over MASP, much larger than that in the vicinity. The modelling with ARPS allowed simulate conditions spatial average in low, medium and upper levels of several variables of the analysed events. Moreover, the ARPS system was used to simulate SB with control and specific runs. Results suggest significant impact of surface cover on rainfall distribution. MXPOL weather radar measurements of SB were important in detecting and nowcasting SB inflow at very high spatial and temporal resolution.

L'objectif majeur de ce travail est d'étudier le climat urbain, principalement en mettant l'accent sur les tendances de la température. Il s’agit principalement de l’augmentation des températures grâce à des techniques d'observation et de modélisation. A cet effet, des données températures de 1950 à 2004 ont étudiées sur plusieurs stations de mesure au Pakistan. Les données de températures annuelles et saisonnières moyennes quotidiennes minimales (Tmin) et maximales (Tmax) de 37 observatoires météorologiques du Pakistan (17 urbain, 7 petite ville et 13 rurale) pour la période 1950-2004 ont d'abord été homogénéisées, puis analysées. Les résultats montrent qu’après les années 1980, Tmin et Tmax tendent à augmenter plus vite que la période d'avant 1980 sur les zones urbaines. Au cours de la période 1980-2004, l'augmentation annuelle de Tmin sur les stations urbaines est observée plus élevée que sur les stations des petites villes et les stations rurales. Pour comprendre l’effet de la taille de la ville, le changement du l’utilisation des sols et la hauteur du bâtiment sur l'évolution des températures minimales et maximales des zones urbaines a été étudié en utilisant le model FVM (Finite Volume Model) et des simulations ont faites pour trois jours à partir de 00:00 (GMT) le 19e jour de chaque mois et se terminant à 00:00 (GMT) le 22e jour de chaque mois. Pour chaque mois, 48 combinaisons possibles de scénarios de simulation sont exécutés (4*4*3) et au total, 576 simulations (48*12) sont exécutés pendant un an. Les résultats centre montrent que Tmin et Tmax augmente lorsque fraction urbaine u, taille de la ville r et hauteur du bâtiment h augmente. Mais on remarque que Tmax augmente plus que le Tmin quand u augmente, Tmin augmente plus que Tmax lorsque r augmente et Tmin augmente plus que Tmax lorsque h augmente. Parmi tous les facteurs urbains (fraction urbaine u, taille de la ville r et hauteur du bâtiment h), la taille de la ville est le facteur majeur qui contribue principalement à augmenter la température minimale plus que température maximale dans les zones urbaines. / The objective of this work is to study the urban climate, mainly by focusing on urban temperature trends. The specific focus is to understand the reasons of increase in minimum temperature through observational and modelling techniques. For this purpose, the temperatures data from 1950 to 2004 measured on several meteorological stations of Pakistan is studied and analyzed. Daily averaged annual and seasonal minimum (Tmin) and maximum (Tmax) temperature data of 37 meteorological observatories of Pakistan (17 urban, 7 town and 13 rural) from 1950 to 2004 is first homogenized and then analyzed. The results show that after 1980s Tmin and Tmax increase faster than the period before 1980s at urban areas. During 1980–2004, the increase in Tmin at major urban stations is observed higher than the smaller towns and rural stations. To understand, the effect of the size of the city, changing land use and the building height on the evolution of minimum and maximum temperatures in urban areas has been studied by using the FVM (Finite Volume Model) model and the simulations are run for three days starting at 00:00 (GMT) on 19th day of each month and ending at 00:00 (GMT) on 22nd day of each month. For each month, 48 possible combinations of simulation scenarios are run (4*4*3) and in total, 576 simulations (48*12) are run for a year. The main results show that Tmin and Tmax increase when urban fraction u, city size r and building height h increase. But it is noticed that Tmax increases more than the Tmin when u increases, Tmin increases more than the Tmax when r increases and Tmin increases more than the Tmax when h increases. Among all urban factors (urban fraction u, city size r and building’s height h), city size is the major factor that mainly contributes to increase the minimum temperature more than the maximum temperature in urban areas.

A combination of the urban heat island effect and a rising temperature baseline resulting from global climate change inequitably impacts socially vulnerable populations residing in urban areas. This dissertation examines distributional inequity of exposure to urban heat by socially disadvantaged groups and minorities in the context of climate justice. Using Cutter’s hazards-of-place model, variables indicative of social vulnerability and biophysical vulnerability are statistically tested for their associations. Biophysical vulnerability is conceptualized utilizing a urban heat risk index calculated from summer 2010 LANDSAT imagery to measure land surface temperature , structural density through the normalized difference built-up index, and vegetation abundance through the normalized difference vegetation index. A cross-section of twenty geographically distributed metropolitan statistical areas (MSAs) in the U.S. are examined using census derived variables at the tract level. The results of bivariate correlation analysis, ordinary least squares regression, and spatial autoregression analysis indicate consistent and significant associations between greater social disadvantage and higher urban heat levels. Multilevel modeling is used to examine the relationship of MSA-level segregation with tract-level minority status and social disadvantage to higher levels of urban heat. Segregation has a significant but varied relationship with the variables, indicating that there are inconsistent associations with urban heat due to differing urban ecologies. Urban heat and social vulnerability present a varying landscape of thermal inequity in different urban areas, associated in many cases with residential segregation.

L'Ilot de Chaleur Urbain (ICU) est l'un des phénomènes du changement climatique les plus documentés. Il est le résultat de températures plus élevées dans le centre des villes que dans leurs banlieues ou les zones rurales alentour et peut avoir des conséquences néfastes sur les habitants des villes, notamment au niveau de la qualité de l'air, la consommation d'énergie, la santé publique et même le taux de mortalité. À Beyrouth, capitale du Liban, la littérature scientifique existante dénote un déficit de recherche sur ce sujet. L’objectif de cette thèse est donc d'étudier l'intensité de l'ICU à Beyrouth, d'identifier les mesures les plus appropriées susceptibles d'en alléger les effets d'un point de vue technique, d'en évaluer les conséquences sur les politiques d'urbanisme et de faire des propositions pour la planification urbaine et la conception des bâtiments à Beyrouth. Dans cette thèse, l'ICU à Beyrouth a été étudié à l'aide du modèle Town Energy Balance (TEB), outil de modélisation servant à calculer les échanges d'énergie et d'eau entre les villes et l'atmosphère, développé par Météo France (Masson, 2000). TEB est inclus dans le système de modélisation des surfaces continentales SURFEX. SURFEX est une contraction de « Surface Externalisée » et c'est un code qui modélise les processus d'échange d'énergie entre l'atmosphère et les surfaces urbaines. Des simulations ont été effectuées à Beyrouth durant une journée, en hiver, le 1er janvier de 00:00 UTC (soit 02:00 heure locale) à 23:00 UTC et une journée, en été, le 1er juillet de 00:00 UTC à 23:00 UTC à des intervalles d'une heure. En été, des écarts significatifs allant jusqu'à 6°C ont été enregistrés pour les températures de canyon. Typiquement, les températures les plus élevées ont été enregistrées dans les zones à forte densité de construction où la part de surfaces travaillées par l'homme est la plus grande et où on a mesuré les albédos les plus bas (généralement 0.2). En hiver, les écarts de température ont été moins significatifs avec un différentiel de 1°C entre les zones à forte densité de construction et les espaces naturels. On en a déduit que les zones avec une grande proportion de végétations ont un rôle réfrigérant à Beyrouth. De plus, nous avons mesuré un écart significatif dans la consommation d'énergie pour la climatisation en été dans différentes parties de Beyrouth ; les simulations ont déterminé la demande requise d'énergie à 50 W/m2 dans les quartiers caractérisés par une grande proportion de jardins et jusqu'à 800 W/m2 dans les quartiers à forte densité de construction. En hiver également, les simulations ont montré des écarts importants au niveau de la demande d'énergie pour le chauffage dans différents quartiers de Beyrouth variant de 20 à 300 W/m2. Six scénarios ont été modélisés sur TEB et ils ont indiqué que l'augmentation de la surface des végétations et l'augmentation de l'albédo des toits produisaient les effets de refroidissement les plus notables. Cette thèse a mis en évidence des opportunités pour améliorer les lois de l'Urbanisme et le Code de la Construction au Liban pour une meilleure prise en compte des aspects microclimatiques urbains et recommande la mise en place de stratégies pour le développement d'espaces verts urbains et pour l'optimisation du refroidissement par les toits. Cette thèse a donc contribué à une meilleure compréhension de l'environnement urbain de la ville de Beyrouth et des paramètres urbains pouvant avoir le plus grand impact sur la réduction des effets de l'ICU. Ce faisant, cette étude a préparé le terrain pour des travaux plus poussés en vue de réduire les effets de l'ICU à Beyrouth dans le but de créer un environnement confortable et sain pour ses habitants et pour les générations futures / The urban heat island (UHI) is one of the more commonly documented phenomena of climate change. It is related to higher urban temperatures in the city centers as compared to the surrounding rural or suburban areas and can lead to unpleasant effects on urban dwellers not least of all on air quality, energy consumption levels, human health, and even mortality rates. In Beirut, the capital city of Lebanon, the literature clearly points to a lack of research on this topic. In addition, there is no evidence that there is a systematic transfer of urban climatic knowledge between concerned stakeholders like urban planning and environmental authorities which is cause for concern given the ever-increasing worldwide attention being given to climate change adaptation and mitigation measures and sustainable city developments. The objective of this research is to therefore investigate the intensity of UHI in Beirut, to identify most suitable measures to alleviate the effects of UHI from a technical perspective, to assess the implications on urban planning processes and to accordingly find opportunities for planning and design practices in Beirut. Beirut is a coastal city that sits on a peninsula that extends westward into the Mediterranean Sea. It covers a surface area of about 20 square kilometers, has a population of approximately 500,000 inhabitants, with a very high population density of about 21,000 inhabitants / km2.The UHI in Beirut was investigated using the Town Energy Balance (TEB) urban surface exchange modeling scheme developed by Météo France (Masson, 2000). TEB is included in the SURFEX land-surface modeling system. SURFEX means “surface externalisée” and it is a code that represents the energy exchange processes that occur between the atmosphere and the urban surfaces. Simulations were accordingly run across Beirut using TEB for 1 day during the winter season on 1 January, from 00:00 UTC (equivalent to 2:00AM local standard time) to 23:00 UTC, and 1 day during the summer season on 1 July from 00:00 UTC to 23:00 UTC with one hour time steps or one hour output results. During the summer significant variations of up to 6oC were found for canyon temperatures whereas areas characterized by dense urban fabrics had higher temperatures typically due to the larger fraction of man-made as opposed to natural surfaces and due to the lower albedo values (generally 0.2). During the winter, temperature variations were not as significant, differing by up to 1oC between aforementioned areas across Beirut. Therefore areas with high garden fractions were found to play an important cooling effect in the simulations for Beirut. In addition, a significant variation in cooling energy usage was found during the summer across Beirut where simulations showed energy demands as low as 50 W/m2 in areas characterized by higher garden fractions whereas simulations were much higher, up to 800 W/m2, in areas with dense urban fabrics. In the summer heating energy demands were also significant ranging from as low as 20-300 W/m2 across Beirut. Six scenarios were also run on TEB which showed that increasing the albedo of roofs and the fraction of gardens had the most noteworthy cooling effects. This research found that there are opportunities for improvement of the Urban Planning Law and the Building Code of Lebanon for better consideration of the urban microclimatic issues and recommended emphasis on urban greening strategies and cool roofing strategies. this thesis contributed to a better understanding of the urban environment of the city of Beirut and the respective urban parameters that have the most significant impact on reducing some of the impacts of the urban heat island phenomenon. In doing so, this research has paved the way for further work on reducing the UHI effect in Beirut, with the ultimate aim of creating a comfortable and safe environment for its residents, and future generations

Global warming risks overthrowing the Earth's climate system, which would mean thatmany communities need to be reshaped and adapted to a new climate. The PublicHealth Agency of Sweden has run a project during the years 2017-2019 that aims toincrease society's ability to identify, prevent and manage harmful heat in existingbuildings. The project focuses on covering the occurrence and developing measures toprevent heat stress in both urban outdoor- and indoor environments. The agency has commissioned a GIS method which, based on the buildings' groundcover, aims to identify areas that are at risk of developing harmful temperatures. Themethod is based on first calculating the total land area of the cities in order to be able tocalculate the proportion of the area covered by high vegetation, hardened surfaces,building bodies and low vegetation. Based on this calculation, areas with a highproportion of paved surfaces and building bodies as well as a low proportion of highvegetation have been identified as areas with a higher risk of developing harmfultemperatures. In this essay, the method has been used to identify risk areas in KalmarCounty's largest cities; Kalmar, Västervik and Oskarshamn. High temperatures can be dangerous for all people, but elderly people are highlighted asa particularly vulnerable group as they have a reduced ability to regulate bodytemperature. Therefore the survey of the thesis has been supplemented with data onwhere people over the age of 65 live in relation to the risk areas in order to make furtherpriorities in where the measures are needed the most. The conclusion is that the need for cooling measures in the mapped cities is greatest inthe urban centers, as the high density of urban areas there provides good conditions fordeveloping high temperatures while a large part of the old population live in thesecentral areas. Several industrial areas have been identified as risk areas in all mappedcities, but there the need for cooling measures is less as they are usually located on theoutskirts of the cities and lack residents over 65 years. The exception is the OldIndustrial Area in Kalmar, whose central location and the circular design of Kalmarindicate that high temperatures develop here at night, which can drive the urban heatisland in the city.

En 2003 des mesures au spectromètre IR à Transformée de Fourier (FTIR) ont permis d'identifier et de mesurer les COV émis par la décharge à ciel ouvert de la Gabarre, principale de l'île Guadeloupe, située entre une zone urbaine et une mangrove. Ces COV ont été retrouvés (2004) la nuit dans les cités, justifiant les plaintes des riverains. Dans le cadre de cette thèse, des mesures au spectromètre de masse portatif MS 200 ont validé ces résultats du FTIR. De nouvelles mesures au MS 200 ont été menées dans toute la zone de la décharge. Les cités concernées étant à l'opposé du flux synoptique d'Alizés-Est, les facteurs météorologiques permettant la dispersion et le transport des COV de la décharge vers la zone urbaine ont été recherchés. La diminution nocturne de l'intensité des Alizés au dessus de l'ile peut laisser place à des phénomènes locaux tels les brises. L'idée d'une brise terre-mer a été éliminée. Un maillage autou~ de la décharge (cités et mangrove) avec 8 thermomètres a révélé un îlot de chaleur urbain nocturnegénérant une brise thermique d'environ Ims- I (mesurée et calculée). Avec les radiosondages Météo France et un SODAR installé dans la décharge, une très forte stabilité dans les basses couches atmosphériques de la couche limite nocturne avec une inversion de surface d'environ 120mvv apparait. Ces facteurs expliquent la pollution des cités par les COV de la décharge, Un modèlevGaussien en tenant compte a été validé par les mesures de COV.vCette étude peut être étendue à d'autres décharges à ciel ouvert et à d'autres types de traitement de polluants de décharge. / In 2003, the VOC emissions coming from "La Gabarre", the main open landfill in Guadeloupe, located in-between an urban area and a mangrove, were identified and quantified with a portable FTIR spectrometer. In 2004, COVs found at nighttime in the urban area nearby confirmed why residents complain about. As part of this thesis, portable mass spectrometer MS 200 measurements validated these FTIR figures. New systematic SM measurements have been carried on around the landfill. Since the polluted urban area stands on the opposite way of the East Trade winds synoptic flux, aIl the weather factors likely to scatter and transport the dump COVs were scrutinized. At night, the strength of the Trade winds decreases over Guadeloupe, which may give way to local phenomena such as breezes. The occurrence of land/sea breeze was eliminated. A close surveying surrounding the landfill with 8 thermometers both in the projects and in the mangrove revealed an urban heat island causing thermal breezes of about lms-l (measured and calculated). Using soundings from Meteo France, and a SODAR inside the dump, we found a great stability of the night boundary layer with a surface inversion near 120m. Pollution of the nearby urban area with landfill COVs is elucidatcd by the above factors. A transport Gaussian model is in agreement with COV measurements. This study can be extended to different open landfills and different types of polluting matters processes in dumps