Spelling suggestions: "subject:"urban pollution"" "subject:"urban collution""
1 |
Investigation of short range dispersion in urban areasZhan, Tao. January 1900 (has links)
Thesis (Ph.D.)--University of California, Riverside, 2007. / Adviser: Akula Venkatram. Includes bibliographical references.
|
2 |
An analysis of the correspondence of environmental coverage in Ohio's six major metropolitan newspapers to citizen perception of environmental problemsMueller, John Frederick. January 2006 (has links)
Thesis (M.S.)--Ohio University, March, 2006. / Title from PDF t.p. Includes bibliographical references (p. 101-105)
|
3 |
Application of mineral magnetic measurements as a pollution proxy for urban road deposited sedimentCrosby, Christopher James January 2012 (has links)
Road Deposited Sediment (RDS) is an important pathway of pollution material in the urban environment. Traditional particulate matter (PM) monitoring methods are typically expensive and time consuming. To date, urban sediment studies have not fully explored the application of mineral magnetic technologies as an alternative to characterise RDS or, perhaps more importantly, their use as particle size proxy. Therefore, this study addresses these issues by determining the extent of any linkages between magnetic properties and the physio-chemical concentrations of RDS. Investigations have focussed on a spatial temporal study (2008-10) of RDS from the City of Wolverhampton (n = 546) and a similar ‘snap-shot’ study of eight selected town and cities across the UK (n = 306), plus a comparison investigation linked to regional monitoring of air sampling units (ASU) (n = 208). A suite of analytical approaches, namely mineral magnetism, laser diffraction, X-Ray Fluorescence spectroscopy (XRF), Scanning Electron Microscopy (SEM) and Loss on Ignition (LOI), were employed to characterize sample properties. Data interrogation identified mainly weak correlations exist between most mineral magnetic parameters and particle size classes (i.e. sand, silt and clay) and respiratory health-related size classes (i.e. PM10, PM2.5 and PM1.0). The few strongest correlations (p <0.001) were found between mineral magnetic concentration and <PM10 parameters. In Wolverhampton this occurred for samples collected during the spring months (March and May), indicating possible seasonal influences on RDS dynamics and sources. Elsewhere in the UK, and at ASU stations, results revealed mainly limited or insignificant (p >0.05) correlations exist between mineral magnetic parameters and particle size. However, for some locations (most notably, London and Scunthorpe), results exhibit signatures perceived to be associated with environmental factors. Detailed multivariate Factor Analysis plots and Geographical Information System (GIS) images have been used to explore these findings further. These illustrate RDS properties of road types (arterial and residential) display significantly different characteristics, with raised mineral magnetic concentrations for arterial roads, compared to lesser concentrations for residential roads, which corresponds to traffic flow data. This is supported by SEM analyses that reveal elevated concentrations of iron oxide spheres in samples collected from arterial roads, which are indicative of inputs from anthropogenic combustion sources. Contextualising these findings within the framework of existing knowledge, a conceptual approach has been presented that explores factors (i.e. sampling area, topography, land use, sediment source and potential mixing), which influence the reliability of using mineral magnetic techniques a particle size proxy. This demonstrates that any increase in the complexity of these factors (sampling area dynamics) can be used to predict the likelihood of being able to employ mineral magnetic measurements as a proxy. To surmise the work overall, despite mineral magnetic technologies offering an inexpensive and rapid means of analysing RDS, its use as a proxy measure for particulate matter appears to be limited by a series of site-related factors but the technique seems to offer valuable insights for pollution source studies.
|
4 |
Effect of heat flux on wind flow and pollutant dispersion in an urban street canyonCheung, Ching, 張靜 January 2006 (has links)
published_or_final_version / abstract / Mechanical Engineering / Master / Master of Philosophy
|
5 |
Effect of heat flux on wind flow and pollutant dispersion in an urban street canyonCheung, Ching, January 2006 (has links)
Thesis (M. Phil.)--University of Hong Kong, 2006. / Title proper from title frame. Also available in printed format.
|
6 |
Estimating Urban Scale Semi-volatile Organic Compound Emissions and Fate Using a Coupled Multimedia and Atmospheric Transport ModelCsiszar, Susan 28 February 2013 (has links)
Cities are sources of persistent organic pollutants (POPs), such as polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs), to surrounding regions and beyond. A spatially resolved, (5×5 km2), dynamic contaminant fate model named Spatially Oriented or SO-MUM was developed by coupling the fugacity based Multimedia Urban Model (MUM) (Diamond et al., 2001; Diamond et al., 2010c) and the Boundary Layer Forecast Model and Air Pollution Prediction System (BLFMAPS) which was developed at Environment Canada (Daggupaty et al., 2006). MUM was updated to contain a revised surface film sub-model which takes into account the dynamic nature of surface films. SO-MUM was illustrated by application to the City of Toronto, Canada. Spatially resolved air emissions of Σ88PCB were estimated to be ~230 (40-480) kg y-1, 280 (50-580) g y-1 km-2, and 90 (16-190) mg y-1 capita-1 and Σ26PBDE were estimated to be 28 (6-63) kg y-1, 34 (7-77) g y-1 km-2 and 11 (2-25) mg y-1 capita-1. These emissions were back-calculated from measured air concentrations and spatial chemical mass inventories yielding emission rates per mass inventory of 0.4 (0.05-1.6) and 0.1 (0.01-0.7) g kg-1inventory y-1, for Σ88PCBs and Σ26PBDEs, respectively. Approximately 30% and 16% of PCB and PBDE emissions emanate from the city’s downtown. Air advection accounted for ~95% (PCB) and ~70% (PBDE) of total air emission losses with the remaining balance depositing to the city. The metric “Urban Travel Distance” or UTD was introduced for quantifying the extent of an urban plume resulting from spatially heterogeneous emissions. For PCBs and PBDEs the UTDs were ~25 and ~30 km. The updated surface film sub-model indicated that films “bounce” higher vapor pressure semi-volatile organic compounds (SVOCs) back into the air but they act as a transient sink from air for lower vapor pressure SVOCs, thereby facilitating transport to surface waters. Model calculations suggest that if the PCB inventory is reduced, volatilization from near-shore Lake Ontario will become a net source of PCBs to air, but that neither near-shore Lake Ontario nor soil would become a significant volatilization PBDE source to air.
|
7 |
Estimating Urban Scale Semi-volatile Organic Compound Emissions and Fate Using a Coupled Multimedia and Atmospheric Transport ModelCsiszar, Susan 28 February 2013 (has links)
Cities are sources of persistent organic pollutants (POPs), such as polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs), to surrounding regions and beyond. A spatially resolved, (5×5 km2), dynamic contaminant fate model named Spatially Oriented or SO-MUM was developed by coupling the fugacity based Multimedia Urban Model (MUM) (Diamond et al., 2001; Diamond et al., 2010c) and the Boundary Layer Forecast Model and Air Pollution Prediction System (BLFMAPS) which was developed at Environment Canada (Daggupaty et al., 2006). MUM was updated to contain a revised surface film sub-model which takes into account the dynamic nature of surface films. SO-MUM was illustrated by application to the City of Toronto, Canada. Spatially resolved air emissions of Σ88PCB were estimated to be ~230 (40-480) kg y-1, 280 (50-580) g y-1 km-2, and 90 (16-190) mg y-1 capita-1 and Σ26PBDE were estimated to be 28 (6-63) kg y-1, 34 (7-77) g y-1 km-2 and 11 (2-25) mg y-1 capita-1. These emissions were back-calculated from measured air concentrations and spatial chemical mass inventories yielding emission rates per mass inventory of 0.4 (0.05-1.6) and 0.1 (0.01-0.7) g kg-1inventory y-1, for Σ88PCBs and Σ26PBDEs, respectively. Approximately 30% and 16% of PCB and PBDE emissions emanate from the city’s downtown. Air advection accounted for ~95% (PCB) and ~70% (PBDE) of total air emission losses with the remaining balance depositing to the city. The metric “Urban Travel Distance” or UTD was introduced for quantifying the extent of an urban plume resulting from spatially heterogeneous emissions. For PCBs and PBDEs the UTDs were ~25 and ~30 km. The updated surface film sub-model indicated that films “bounce” higher vapor pressure semi-volatile organic compounds (SVOCs) back into the air but they act as a transient sink from air for lower vapor pressure SVOCs, thereby facilitating transport to surface waters. Model calculations suggest that if the PCB inventory is reduced, volatilization from near-shore Lake Ontario will become a net source of PCBs to air, but that neither near-shore Lake Ontario nor soil would become a significant volatilization PBDE source to air.
|
8 |
Two-dimensional computational study on indoor/outdoor air quality relationship in urban buildingsLai, Kwong-kei, Murphy. January 2007 (has links)
Thesis (M. Phil.)--University of Hong Kong, 2007. / Title proper from title frame. Also available in printed format.
|
9 |
Two-dimensional computational study on indoor/outdoor air quality relationship in urban buildingsLai, Kwong-kei, Murphy., 賴廣麒. January 2007 (has links)
published_or_final_version / abstract / Mechanical Engineering / Master / Master of Philosophy
|
10 |
A poluição atmosférica e o clima urbano: um olhar sobre a inspeção veicular no município de São PauloSantos, Andre Souza 06 October 2015 (has links)
Made available in DSpace on 2016-04-27T18:15:46Z (GMT). No. of bitstreams: 1
Andre Souza Santos.pdf: 3149722 bytes, checksum: 58f05c92fcbf5101af18370744baf4b0 (MD5)
Previous issue date: 2015-10-06 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This thesis of Master's Degree studies the air pollution in São Paulo as a result of automotive vehicles's predominance, taking as an example its influence on urban climate, comprising a period that started on the 1980s and is still in force. This analysis has as background the urbanization and the introduction of the automotive industry fomenting the use of collective and individual road s transports. Concerns about air quality and climate have turned the vehicles, once synonymous of economic progress and connected to a socio-economic identity,a worry for the urban environment and, as a solution, mechanisms to promote a road control were created. In the 1980s the guidelines were created for the control of automotive pollutants, in the 1990s, it was introduced Municipal rotation which has not produced the expected results in reducing emissions in the atmosphere,, then, only in 2008 was added the mandatory vehicle inspection in the city of São Paulo as a result of agreement between the countries that have ratified the Kyoto Protocol in1997 whose intention was to reduce between 2008 and 2012 greenhouse gas emissions in at least 5.2% compared to 1990s levels. According to the Intergovernmental Panel on Climate Change (IPCC) human action is the main responsible for the changes in air quality and climate and, if the countries achieve their goals, the pollution and global temperature could be reduced in between 1.4°C and 5.8°C until 2100.The study revealed that according to the urban development of St. Paulo in the field of displacements was prioritized road transport, this way, vehicular emissions of particulate materials in the atmosphere are connected to changes in the city climate and several health disorders,especially in winter when the polluted air disperses with difficulty although it is hard to quantify and qualify the real damage. As a result, there is the need to rethink the means of establishing shifts priorities for urban and environmental planning. In this case, the inspection car proved to be inefficient because, although the road contro it's hard, many vehicles without mechanical conditions remain in circulation mainlyin the suburbs directly influencing the data on air quality / Esta dissertação de mestrado estuda a poluição atmosférica no município de São
Paulo como consequência da predominância dos veículos automotores nos meios
de deslocamentos tal como sua influência no clima urbano compreendendo um
período atual a partir da década de 1980. Esta análise tem como fundo a
urbanização e a introdução da indústria automotiva fomentando o uso do
transporte rodoviário coletivo e individual. A preocupação com a qualidade do ar
e do clima, fizeram dos veículos outrora sinônimo de progresso econômico e
característica de uma identidade socioeconômica uma preocupação ao ambiente
urbano, razão pela qual foram criados mecanismos de promover um controle
viário. Na década de 1980 foram criadas as diretrizes para o controle de poluentes
autmotivos, na década de 1990, foi introduzido o Rodízio Municipal o qual não
apresentou os resultados esperados na redução das emissões na atmosfera,
então, somente em 2008 foi introduzida a inspeção veicular obrigatória na cidade
de São Paulo como consequência do compromisso firmado entre os países que
ratificaram o Protocolo de Kyoto em 1997, cuja intenção era reduzir entre 2008 e
2012 as emissões de gases em pelo menos 5,2% em relação aos níveis da
década de 1990. De acordo com o Intergovernmental Panel on Climate Change
(IPCC) a ação humana é a principal responsável pelas alterações da qualidade
do ar e do clima e caso os países alcancem as metas propostas, será possível
reduzir a temperatura global entre 1,4°C e 5,8°C até 2100. Para alcançar o
objetivo da pesquisa foram analisadas séries temporais, estudos das tendências
globais, os principais tratados e protocolos sobre as questões ambientais e
emissões antrópicas. Ficou evidenciado que de acordo com a evolução urbana de
São Paulo na esfera dos deslocamentos foi priorizado o transporte rodoviário,
desse modo, as emissões veiculares de materiais particulados na atmosfera estão
vinculadas às alterações do clima citadino e diversos problemas de saúde,
sobretudo no inverno quando o ar poluído se dispersa com mais dificuldades,
embora seja difícil quantificar e qualificar os reais danos. Em razão disso, há a
necessidade de repensar os meios de deslocamentos estabelecendo prioridades
para planejamento urbano e ambiental. Nesse caso, a inspeção veicular mostrouse
ineficiente pois o controle viário embora seja rígido, muitos veículos sem
condições mecânicas continuam em circulação principalmente nos bairros
periféricos influenciando diretamente nos dados sobre a qualidade do ar
|
Page generated in 0.0642 seconds