Os efeitos causados pela presença de áreas urbanizadas da Região Metropolitana de São Paulo (RMSP), conhecidos por ilha de calor urbana, são estudados através da modelagem numérica e da análise de alguns dados observacionais, coletados no período de inverno de 1999 durante a 1ª Fase intensiva de medidas de campo do Projeto Temático FAPESP “Meteorologia e Poluição do Ar em São Paulo” e da rede automática da CETESB. Através da utilização de imagens do satélite LANDSAT-5, foi obtido um arquivo de ocupação do solo na RMSP numa resolução de aproximadamente 424 m. Foram definidos dois tipos de ocupação urbana que diferem principalmente na verticalização e espaçamento entre as construções. Simulações realizadas com uma parametrização adequada ao tratamento das propriedades da superfície em áreas urbanas, o modelo RAMS-TEB, mostraram que as fontes antropogênicas de calor de origem veicular são de grande importância no ciclo diurno de temperatura e umidade na RMSP. Uma comparação entre os dados simulados pelo modelo e dados observacionais de superfície apresentou coeficientes de correlações superiores a 0,9 para a temperatura e superiores a 0,8 para a umidade relativa. A interação entre a brisa marítima e a ilha de calor intensifica as zonas de convergência no centro da cidade, podendo ocasionar a re-circulação de poluentes nessa região. Simulações sobre o efeito da urbanização mostram que a ilha de calor urbana faz com que haja uma propagação mais rápida da frente de brisa até o centro da RMSP, que permanece estacionária por algum tempo nessa região. Os efeitos da topografia mostraram-se fundamentais na intensidade da brisa marítima e sua propagação sobre o continente. A presença de grandes corpos d’água, tais como a represa de Guarapiranga e Billings, contribui para a diminuição das amplitudes do ciclo diurno de temperatura na RMSP através das circulações do tipo brisa lacustre geradas pelos mesmos. O uso de um modelo de dispersão mostrou que, com a propagação da frente de brisa para o interior (na direção SE-NW), poluentes emitidos na RMSP são transportados para áreas remotas, diminuindo a concentração dos mesmos nas regiões emissoras. / The effects caused by urbanization in the Metropolitan Area of São Paulo (MASP), known as urban heat island, are studied through the use of numerical modeling and some observed data, collected in the 1999’s winter time during the first phase of intensive field measurements from the Thematic Project FAPESP “Meteorology and Air Pollution in São Paulo” and also from CETESB automatic network. A 424 m resolution land use file was created using LANDSAT-5 satellite pictures where two different kinds of urban regions were identified. The main differences between these regions are the vertical structure and spacing between buildings. Simulations performed with an appropriate parameterization for the treatment of surface properties in urban areas showed that anthropogenic sources due to traffic are of great importance to the temperature and humidity diurnal cycle in MASP. Comparisons between simulated and observed surface data had a correlation coefficient greater than 0.9 for temperature and greater than 0.8 for relative humidity. The interaction between the see breeze and the urban heat island intensify the convergence zones in the center of the city, eventually causing the re-circulation of pollutants in this region. Simulations of the urbanization effects showed that the urban heat island is responsible for a faster propagation of the sea breeze front up to the center of the MASP, remaining stationary in this region for some time. The topographic effects are fundamental in the intensity of the sea breeze and its inland propagation. The presence of large water bodies, as the Guarapiranga and Billings Dams, contribute to a decrease in the temperature diurnal cycle amplitudes because of the lake breeze circulations generated by them. The use of a simple dispersion model showed that with the propagation of the sea breeze front to the countryside (in the direction SE-NW), pollutants emitted in MASP are transported to remote areas, causing a decrease in the concentration of these pollutants in the source region.

Com a crescente evolução da mancha urbana das cidades, o ser humano intensificou o seu uso sobre o espaço, ocasionando certas conseqüências socioambientais, intensificadas através de fenômenos climáticos, tais como: enchentes, a piora da qualidade do ar e do aumento da temperatura nas cidades, comparada a sua área entorno. Este último, também é conhecido como Ilha de calor. A área de estudo contemplada nesta pesquisa se justificativa pelo fato de apresentar: a) um crescimento acelerado da população urbana a partir de meados da década de 1970; b) um Intenso processo de verticalização iniciado na década de 1980 e c) por conseguinte a expansão da malha urbana da cidade, que convive com uma arborização muito reduzida. A partir destes argumentos, o presente trabalho procurou investigar a hipótese da constituição de um clima urbano associado ao crescimento da cidade sede do município de Viçosa. Para isto, primeiramente, analisou-se a série histórica da estação climatológica de Viçosa entre 1968 e 2006. E, em seguida, utilizou-se da técnica de transetos móveis, com a utilização de um termohigrômetro digital de leitura direta (MINIPA-MT-241), envolvido em tubo PVC recoberto por papel alumínio e colocado do lado de fora do carro há uma altura de aproximadamente 2,0m de altura. Este procedimento foi realizado em três escalas de análise: campocidade, área urbana e o centro da cidade e estações sazonais distintas. Depois de realizados os experimentos e analisado os registros históricos de temperatura do ar, pode-se dizer que Viçosa ainda não constitui um clima urbano, muito embora, possa ter sido possível identificar ilhas de calor na cidade, principalmente à noite. / With the increasing development of urban stain of cities, the human being intensified its use on the area, causing certain social consequences, intensified by climatic phenomena, such as flooding, the worsening air quality and increasing the temperature in cities compared to its surrounding area. The latter is also known as heat island. The study area included in this search was justified because the present: a) an accelerated growth of urban population from the mid-1970s, b) a Intensy verticalisation process started in the 1980s and c) therefore the expansion of urban network of the city, living with a very limited stock. From these arguments, this study sought to investigate the possibility of setting up a climate associated with the urban growth of the city headquarters of the municipality of Viçosa. For this, first analyzes the historical series of the climatological station of Viçosa between 1968 and 2006. And then it was used the technique of mobile transects, using a digital direct reading termohigrômetro (MINIPA-MT-241), involved in PVC pipe covered by aluminum foil and placed outside the car there is a height of approximately 2.0 m high. This procedure was performed on three scales of analysis: country-city, urban area and the city center and seasonal distinct seasons. After the experiments performed and analyzed the historical records of air temperature, we can say that Viçosa still not an urban environment, though, might have been possible to identify islands of heat in the city, mainly at night.

The process of urbanization dramatically alters the landscape which can have negative effects on the environment, and thereby, places the inhabitants and the city itself at risk. The development of an urban heat island can have severe health implications for city inhabitants during prolonged heat waves. Urbanisation also alters hydrological processes, which can place urban areas at a greater threat of surface flooding during heavy rainfall. As cities are continuing to expand, and as climate change proceeds, these problems are only likely to be exacerbated and there is a need to find ways to reduce these negative effects.This thesis builds upon previous modelling work on the effect of greenspace on the climate and hydrology of Manchester, U.K. The aims were to test the predictions of this model by investigating the effect of trees and grass in reducing surface temperatures and rainfall runoff, and further investigate their effects on air and globe temperatures. Surface, globe, and air temperatures were measured on grass and concrete areas in full sun and tree shade, both under large tree canopies, and below those of a range of street tree species. The rainfall runoff from experimental plots covered in asphalt, asphalt plus a tree and grass, was also investigated. Grass reduced surface temperatures in full sun by up to 24°C, in good agreement with previous models, but permanent tree shade reduced concrete temperatures by almost as much, up to 19°C. Tree shade also reduced globe temperatures by up to 7°C, a reduction which can improve human comfort on hot day. These results indicate that both forms of vegetation will act regionally, reducing the urban heat island effect, but that trees can dramatically improve the local environmental conditions. Street trees reduced surface and globe temperatures by rather less, 12°C and 4°C respectively, though trees with a higher leaf area index provided greater cooling. Because of advection neither trees nor small areas of grass had an effect on local air temperatures.Grass was most effective vegetation type at preventing rainfall runoff, reducing runoff coefficients of the plots from around 60% on asphalt to near zero. However, tree units also reduced the runoff coefficient to around 25%, despite having a canopy that covered only a small proportion of the plot, suggesting that much of the rainfall must have infiltrated into the planting hole. These reductions are higher than predicted by previous modelling, highlighting the importance of greenspace on the hydrology of the urban environment.The results suggest that trees and grass provide complementary environmental benefits in cities, and that the benefits of trees strongly depend on species and planting conditions

The urban heat island (UHI) is a problem that is likely to be exacerbated by ongoing climate change, but it is often claimed that urban trees can mitigate it and hence adapt our cities to climate change. Many researchers have attempted to quantify the cooling effects of trees using modelling approaches. However, the major disadvantage of most of the models is that they consider all vegetation to act as a single saturated layer and that their effect is merely proportional to its surface cover. Therefore, they fail to take into account potential differences between tree species and the effect of different environmental and growing conditions. To address this issue four different studies were conducted in Manchester, UK from February, 2010 to December, 2012. The studies compared the growth and cooling abilities of several commonly planted urban tree species, and investigated a single species planted in a range of growing conditions: investigating the effect of urban soil compaction and aeration and also the effect of urbanization and simulated climate change in the rooting zone. Overall, our studies showed that species selection and growing conditions can substantially alter the evapotranspirational cooling provided by urban trees. Fast growing species such as Pyrus calleryana, with their dense and wide canopy can provide cooling up to 2.2 kW tree-1, 3-4 times that of Sorbus arnoldiana, which have a thinner and narrower canopy and a moderate growth rate. P. calleryana was also investigated under three contrasting growth conditions: in cut-out pits in pavements; in grass verges; and in pits filled with Amsterdam soil. Trees in the less compacted Amsterdam soil had grown almost twice as fast as those in pavements and also had better leaf physiological performance. Together with a longer growing season, and better uptake of soil nutrients and moisture, trees grown in Amsterdam soil provided evapotranspirational cooling of up to 7kW, 5 times higher than those grown in pavements. Another experiment in which P. calleryana trees were planted in 3 standard planting techniques with non-compacted load bearing soils and with or without permeable slabs showed that optimum cooling is not only dependent on preventing soil compaction but also on ensuring that the covering materials are permeable to oxygen. Trees in the open pits provided up-to 1 kW of cooling, compared to around 350 and 650 W by the small and large covered pits respectively. Our final experiment showed that urbanization can increase tree growth by 20-30%; however, despite being under more water stressed conditions trees grown in simulated climate change plots had 40% higher sap flux density, and hence cooling potential. The study suggested that at least with P. calleryana, transpirational cooling benefit might be enhanced in places like Manchester with increased soil temperature in future, but potentially at the expense of photosynthesis and carbon gain. Together these studies show that evaporative cooling of trees depends strongly on both species and growing conditions. If incorporated into regional and local energy exchange models our results can help us to quantify the magnitude and effectiveness of greenspaces in the city in adapting them to climate change.

Urban populations worldwide are expanding rapidly and consequently a large number of people are becoming exposed to hazards inherent in cites. Phenomena such as the urban heat island can exacerbate the effects of heatwaves, and land surface sealing can lead to flash flooding. Cities are also the sites of enhanced air and water pollution from non-point sources such as concentrated motor vehicle use. Climate change predictions for the UK include increased winter precipitation and an increase in frequency of summer heatwaves. This will put further pressure on urban residents and infrastructure. Roof greening can be used within climate change adaptation schemes because green roofs have a range of environmental benefits which can help urban infrastructure become more sustainable. This thesis empirically quantifies several of these benefits, and the processes influencing them, by monitoring real green roofs in Manchester. A number of novel discoveries were made. Green roofs act as passive filters of airborne particulate matter. 0.21 tonnes of PM10 (2.3% of the inputs) could be removed from Manchester city centre in a maximum extensive green roof scenario. Species and site differences in particle capture were exhibited and related to morphology and proximity to sources respectively. An intensive green roof was able to lower the monthly median overlying air temperature at 300 mm by up to 1.06 oC. A combination of drought and mismanagement caused damage to the vegetation on one of the green roofs, with a subsequent reduction in the cooling effect. Daytime air temperatures were higher than over an adjacent bare roof for a larger proportion of the day than over the undamaged roof, and lower cooling was observed at night. A site-specific methodology was devised to monitor the rainwater runoff from an intensive green roof and an adjacent bare roof. Average runoff retention of 65.7% was observed on the green roof, compared to 33.6% on the bare roof. Season and rainfall amount had significant impacts on retention, however, many other explanatory variables such as Antecedent Dry Weather Period (ADWP) and peak rainfall intensity had no demonstrable, significant impact. Intensive roof construction on 10% of the rooftops in Manchester city centre would increase annual rainfall retention by 2.3%. The runoff was characterised with regards to heavy metals and nutrients. Nutrient levels were found to be not a significant problem for water quality, however, Environmental Quality Standards (EQS) values for protection of freshwater were exceeded for concentrations of Cu, Pb and Zn. High metal concentrations within the sediments may be acting as sources of pollution, particularly in the case of Pb. The age of the green roof means that past atmospheric deposition of Pb could be contributing to the runoff quality. The multi-benefit aspect of green roofs is discussed in the light of the results of this thesis and recommendations made for policy makers and the green roof construction industry.

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abstract: Urban heat is a growing problem that impacts public health, water and energy use, and the economy and affects population subgroups differently. Exposure and sensitivity, two key factors in determining vulnerability, have been widely researched. This dissertation focuses on the adaptive capacity component of heat vulnerability at the individual, household, and community scale. Using a mixed methods approach and metropolitan Phoenix as a test site, I explored how vulnerable communities understand and adapt to increasing extreme urban heat to uncover adaptive capacity that is not being operationalized well through current heat vulnerability frameworks. Twenty-three open-ended interviews were conducted where residents were encouraged to tell their stories about past and present extreme heat adaptive capacity behaviors. A community-based participatory research project consisting of three workshops and demonstration projects was piloted in three underserved neighborhoods to address urban heat on a local scale and collaboratively create community heat action plans. Last, a practitioner stakeholder meeting was held to discuss how the heat action plans will be integrated into other community efforts. Using data from the interviews, workshops, and stakeholder meeting, social capital was examined in the context of urban heat. Although social capital has been measured in a multitude of ways to gauge social relationships, trust, and reciprocity within a community, it is situational and reflects a position within the formal and informal aspects of any issue. Three narratives emerged from the interviews illuminating differentiated capacities to cope with urban heat: heat is an inconvenience, heat is a manageable problem, and heat is a catastrophe. For each of these narratives, generic adaptive capacity is impacted differently by specific heat adaptive capacity. The heat action plan workshops generated hyper-local heat solutions that reflected the neighborhoods’ different identities. Community-based organizations were instrumental in the success of this program. Social capital indicators were developed specific to urban heat that rely on heavily on family and personal relationships, attitudes and beliefs, perceived support, network size and community engagement. This research highlights how extreme heat vulnerability may need to be rethought to capture adaptive capacity nuances and the dynamic structure of who is vulnerable under what circumstances. / Dissertation/Thesis / Doctoral Dissertation Sustainability 2019

Meteorological data from two observation sites in Uppsala, the Observatory Park (Op) andthe Geocentre (Gc), during the period January 1998 to September 2000, have been used tocheck the differences in the temperature climate at the two places. Since Op is situatedcloser to the city centre than Gc the site is thought to be more affected by the so calledurban heat island effect. Dependence on different meteorological parameters, time of theday and time of the year, has been investigated and different methods to correct thetemperature for the inhomogeneity that was introduced when the observation site wasmoved from the Observatory Park to the Geocentre. From the different methods investigated it is shown that to correct the temperaturesmeasured at the Geocentre to make them represent the conditions at the Observatory Parka division according to wind speed, wind direction, cloudiness and time of the year wasshown to be the most reliable method. But if it had been possible to divide the material alsointo hours of the day, this would probably have increased the reliability of the correction.For practical purposes a correction simply based on the monthly mean differences betweenthe two sites is probably accurate enough, as the most important factor is the annual cycle inthe temperature difference between the two urban sites. / Väderdata från två observationsplatser i Uppsala, Observatorieparken (Op) och Geocentrum(Gc), under perioden januari 1998 till september 2000, har använts för att undersökaskillnader i temperaturklimatet vid de två platserna. Eftersom Op ligger närmare stadenscentrum än Gc, anses platsen vara mer påverkad av den så kallade värmeöeffekten. Beroendeav olika meteorologiska parametrar, tid på dygnet och tid på året, har undersökts, samt olikametoder att korrigera för inhomogeniteten i temperaturen som introducerades dåobservationsplatsen flyttades från Observatorieparken till Geocentrum. Bland de olika metoder som undersökts för att korrigera de vid Geocentrum uppmättatemperaturerna så att de ska representera förhållandena vid Observatorieparken, visas enuppdelning med avseende på vindhastighet, vindriktning, molnighet och tid på året vara denmest pålitliga metoden, men hade det varit möjligt att dela in materialet även i tid på dygnet,skulle detta troligtvis ha ökat pålitligheten av korrektionen. För praktisk användning är enkorrektion baserad endast på de månatliga medelskillnaderna mellan de två platsernaantagligen tillräcklig, eftersom den viktigaste faktorn är den årliga cykeln itemperaturskillnaden mellan de två platserna.

The world is currently facing a changing climate and the various negative effects that it entails. In recent decades, enhanced climate adaptation responses have therefore become increasingly common across the world. In Sweden, climate adaptation through urban planning has mainly focused on challenges such as flooding, erosion and sea level rise rather than heat. However, warmer temperatures are recognised as one of the main challenges of climate change, not least for urban areas and the people who live there. Thus, the aim of this thesis was to explore how Swedish municipalities with larger cities work with urban planning to address the challenges of warmer temperatures and how strategies for adaptation to urban heat are portrayed in municipal planning documents. This was done through a qualitative document analysis of municipal planning documents from three Swedish municipalities, Huddinge, Kristianstad and Norrköping. The results show that Swedish municipalities in the planning documents mainly portray urban heat as problematic but that some municipalities also choose to highlight possible positive effects. Furthermore, the results show that preserving and enhancing green structures of various sizes can be considered the main strategy for climate adaptation to urban heat in Swedish municipalities. However, some municipalities are also working with a few other strategies, including local investigations, technical measures and increased local knowledge. Lastly, some Swedish municipalities can also be understood to have as strategy to work with clearly formulated goals and measures in their planning documents.

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