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Global environment: An emerging challenge for international cooperation building a legal regime for ozone layer depletion.Hosseini, Jamaladdin. January 1992 (has links)
Global environment is presenting new opportunities and challenges for international cooperation. The depletion of the ozone layer is one of the successful cases where the world community has demonstrated a rare consensus to address a global problem. This study: (1) examines the role of international law and institutions in shaping a regime for ozone layer depletion as formalized in the 1987 Montreal Protocol; (2) evaluates contributions of the ozone regime to the development of international environmental law, and (3) analyzes its implications for future international cooperation. Using regime theories as a methodological framework, the study integrates science, policy, law and institutions to show how they interact to create understandings, practices, and procedures in international relations. Traditionally, regime theorists have focused on power and interest to explain international cooperation. The existing theories were found to be inadequate for the analysis of ozone regime. I have offered an alternate explanation by incorporating the element of "law" into regime studies and linking regimes with "institutions"--the raison d'etre of the regimes. This modified explanation helps to provide a better understanding of the formation of the ozone regime. The study suggests that the ozone regime has produced a new generation of environmental norms. These norms, both procedural and substantive, put "flesh on the bone" of environmental law and keep ozone regime as a political process in motion, thus, adapting to the changing technological and scientific environment. Moreover, the ozone regime marks a turning point in the shift of emphasis from single-issue pollution laws to an encompassing law of the atmosphere. A new form of international cooperation also emerged from ozone negotiations. This cooperation was promoted by joint efforts of the United Nations Environment Programme (UNEP) and the world scientific community. UNEP used scientific findings to persuade the parties to the ozone negotiations to re-evaluate their political stance in light of evolving scientific knowledge. At a time when traditional bases of power seem to be eroding, international institutions are viable structures to initiate efforts to address human concerns and facilitate decisions by the international community. Similarly, the world scientific community may prove influential in future global policymaking, in particular on the issues with high degrees of scientific uncertainty.
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A time-dependent spectral point spread function for the OSIRIS optical spectrograph2013 May 1900 (has links)
The primary goal of the recently formed Absorption Cross Sections of Ozone (ACSO) Commission is to establish an international standard for the ozone cross section used in the retrieval of atmospheric ozone number density profiles. The Canadian instrument OSIRIS onboard the Swedish spacecraft Odin has produced high quality ozone profiles since 2002, and as such the OSIRIS research team has been asked to contribute to the ACSO Commission by evaluating the impact of implementing different ozone cross sections into SASKTRAN, the radiative transfer model used in the retrieval of OSIRIS ozone profiles. Preliminary analysis revealed that the current state of the OSIRIS spectral point spread function, an array of values describing the dispersion of light within OSIRIS, would make such an evaluation difficult. Specifically, the current spectral point spread function is time-independent and therefore unable to account for any changes in the optics introduced by changes in the operational environment of the instrument. Such a situation introduces systematic errors when modelling the atmosphere as seen by OSIRIS, errors that impact the quality of the ozone number density profiles retrieved from OSIRIS measurements and make it difficult to accurately evaluate the impact of using different ozone cross sections within the SASKTRAN model.
To eliminate these errors a method is developed to calculate, for the 310-350 nm wavelength range, a unique spectral point spread function for every scan in the OSIRIS mission history, the end result of which is a time-dependent spectral point spread function. The development of a modelling equation is then presented, which allows for any noise present in the time-dependent spectral point spread function to be reduced and relates the spectral point spread function to measured satellite parameters. Implementing this modelled time-dependent spectral point spread function into OSIRIS ozone retrieval algorithms is shown to improve all OSIRIS ozone profiles by 1-2% for tangent altitudes of 35-48 km. Analysis is also presented that reveals a previously unaccounted for temperature-dependent altitude shift in OSIRIS measurements. In conjunction with the use of the time-dependent spectral point spread function, accounting for this altitude shift is shown to result in an almost complete elimination of the temperature-induced systematic errors seen in OSIRIS ozone profiles. Such improvements lead to improved ozone number density profiles for all times of the OSIRIS mission and make it possible to evaluate the use of different ozone cross sections as requested by the ACSO Commission.
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Role of synoptic weather systems in surface ozone concentration in Durban region.Langa, Mduduzi Amos. January 1995 (has links)
Measurements of surface ozone in Durban have been
undertaken since September 1994 until August 1995 using a Dasibi ozone monitor model 1108. There is a seasonal
variation in surface ozone with a small amplitude of 6.5 ppb. The mean maximum of 12.5 ppb is experienced in August and the minimum in December (6 ppb). The late winter peak and the sharp rise from June to July is possibly related to the greater accumulation of ozone at the surface due to the poor dispersion, higher frequency of inversions and lower mixing depth.
The study also focuses on the relationship between synoptic weather systems and daily ozone concentrations in an attempt to establish if any relationship exists. The analysis suggests that there is an increase in ozone concentration during the pre-frontal and established high pressure systems and a reduction in ozone under postfrontal conditions.
The mean diurnal variation in surface ozone depicts a maximum between solar noon and 14:00, which is typical of an urban-industrial environment, in which ozone precursor gases have built up during the morning. However, a secondary peak in the early morning during winter and autumn was more difficult to explain and is thought to be due to the transport of ozone from the interior in the mountain-plain wind systems.
Comparison of ozone values at Durban with results available from the other locations in South Africa such as Cape Point and the Eastern Transvaal Highveld has been undertaken.
Ozone values at Durban are lower than Cape Point, which is a representative of a background monitoring station. It ls hypothesised that those low ozone concentrations may be due to high NOx which in turn depletes ozone. / Thesis (M.Sc.)-University of Natal, 1995.
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Spatial distribution and co-occurrence of surface-atmosphere exchange processesMitic, Constance M. (Constance Maria) January 1993 (has links)
Grid-type flight patterns at an altitude of 30 m were executed in the summer of 1991 by the Canadian Twin Otter flux research aircraft over a 15 km x 16.5 km agricultural area, as part of the San Joaquin Valley Air Quality Study/California Ozone Deposition Experiment (SJVAQS/CODE). Fast-response on board sensors for turbulence, temperature and gas concentrations permitted the spatial mapping of fluxes of momentum, sensible heat, moisture, CO$ sb2$ and ozone. Flux maps were produced in the form of GIS-interpolated 1 km averages, and in the discrete form of those coherent structures of the turbulent process, intermittent in time and space, which dominate the exchange of scalars between the ground and the atmosphere. The magnitude of surface-related mesoscale contributions to the flux was also quantified. Flux observations were compared against radiometrically observed surface temperatures and vegetation indices (NDVI), observed from aircraft and satellite (NOAA AVHRR), and surface characteristics from ground surveys. / Flux maps showed the expected correspondence between greenness, evapo(trans)ration (ET) and CO$ sb2$ exchange. Discrepancies between ozone flux maps and maps of greenness, ET or CO$ sb2$ were more pronounced than would be consistent with the hypothesis of stomatal control of ozone uptake. More insight into control mechanisms on ozone exchange is gained by an examination of the spatial coincidence between transporting structures for the various scalars (heat, moisture, CO$ sb2$ and ozone), through the Jaccard coefficient of co-location (J), which showed a lower value ($ rm0.3<J<0.6$) for coincidence in transfer between ozone and moisture than between moisture and CO$ sb2$ ($ rm0.5<J<0.8$). Analysis of J over the various land-use and crop-types in the test area, opens a door to a more differentiated understanding of the physical and physiological driving forces behind ozone uptake by soil and vegetation.
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Lagrangian behaviour and properties of deep stratospheric intrusionsTrépanier, Pier-Yves. January 1900 (has links)
Thesis (M.Sc.). / Written for the Dept. of Atmospheric and Oceanic Sciences. Title from title page of PDF (viewed 2008/12/10). Includes bibliographical references.
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Photochemical processing of long range transported Eurasian pollution in the Northeast Pacific troposphere /Price, Heather Umbehocker, January 2004 (has links)
Thesis (Ph. D.)--University of Washington, 2004. / Vita. Includes bibliographical references (leaves 196-214).
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Global environment an emerging challenge for international cooperation building a legal regime for ozone layer depletion /Hosseini, Jamaladdin. January 1992 (has links)
Thesis (Ph. D.)--University of Arizona, 1992. / Includes bibliographical references (leaves 224-241).
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Correção atmosferica de imagens do sensor AVHRR/NOAA utilizando produtos atmosfericos do sensor MODIS/TERRA / Potencial of use of atmospheric products of sensor MODIS/TERRA, for atmospheric correction of images AVHRR/NOAANascimento, Cristina Rodrigues 23 February 2006 (has links)
Orientador: Jurandir Zullo Junior / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola / Made available in DSpace on 2018-08-08T10:45:00Z (GMT). No. of bitstreams: 1
Nascimento_CristinaRodrigues_M.pdf: 15175487 bytes, checksum: d9905da2c3f9b6c5fa573693ce9e61a0 (MD5)
Previous issue date: 2006 / Resumo: O sensoriamento remoto nas regiões espectrais do visível e do infravermelho próximo constitui uma das ferramentas mais importantes para o entendimento da biosfera e de suas dinâmicas. Entretanto, estas duas regiões são afetadas pelos efeitos atmosféricos tais como, o espalhamento e a absorção,ocasionados por sua vez pelos aerossóis e gases atmosféricos. Na tentativa de obter o fator de reflectância bi-direcional da superfície terrestre, nos canais 1 e 2 do sensor AVHRR, foi realizada a correção atmosférica, baseada na entrada de dados, tais como espessura óptica dos aerossóis, coluna total de vapor d?água e carga total de ozônio, respectivamente fornecidos pelo sensor MODIS. O intuito da utilização deste sensor está diretamente relacionado à obtenção das informações, necessários para a correção atmosférica, considerando-se a variabilidade dos parâmetros no tempo e no espaço. Para tanto foi utilizado o aplicativo SCORADIS, fundamentado no modelo de transferência radiativa 5S, então adaptado, para possibilitar a correção atmosférica de toda a imagem do AVHRR a partir da entrada das imagens correspondentes aos planos atmosféricos, através da utilização de quatro metodologias distintas de correção atmosférica. As análises realizadas indicaram que as correções realizadas a partir dos dados atmosféricos do sensor MODIS apresentaram resultados coerentes com o esperado após a eliminação dos efeitos de espalhamento e de absorção atmosférica, nos canais 1 e 2 do NOAA-17, nas duas datas consideradas (14/07/2004 e 30/08/2005). Para o NDVI, a diferença percentual entre as imagens com e sem correção chegaram a ser de, aproximadamente, 60%, o que ressalta a importância da correção atmosférica destes canais, principalmente no acompanhamento da vegetação a partir de imagens multitemporais. Não se observou diferença significativa entre as metodologias utilizadas para a entrada dos dados atmosféricos no sistema de correção atmosférica, devido, possivelmente, à magnitude dos valores utilizados e à áreateste escolhida. Os produtos obtidos a partir das imagens do MODIS mostraram potencial para utilização na estimativa dos principais parâmetros atmosféricos necessários para a correção atmosférica (como a espessura óptica dos aerossóis e conteúdo de vapor d'água e ozônio) e que são de grande dificuldade para obtenção em campo / Abstract: Remote sensing in the spectral regions of visible and infrared is one of the most important techniques used for studying the biosphere. However these two spectral regions are affected by atmospheric effects as scattering and absorption, caused by aerosols and atmospheric gases. In the attempt to obtain the real reflectance of ground surface, in channels 1 and 2 of AVHRR sensor, was performed the atmospheric correction of two NOAA images acquired on July/14/2004 and August/30/2005, based on atmospheric data supplied by the MODIS sensor, considering the spatial and temporal variability of these parameters. The system SCORADIS, based on the radiative transfer model called 5S, was adapted to read images having values of aerosols optical thickness, water vapor content and ozone contents corresponding spatially to each pixel of a AVHRR/NOAA image. Four distinct methodologies were used to define the images of atmospheric parameters. Coherent results were obtained using atmospheric data from MODIS, indicating that the scattering and absorption effects were correctly eliminated from the NOAA images in the two dates considered. The difference between the NDVI calculated with corrected and noncorrected images was up to 60%, showing the importance of using corrected images in applications based on multitemporal images. There was not observed significant difference among the four methodologies applied to define the atmospheric data used in the atmospheric correction system due, maybe, to the magnitude of the values and to the atmospheric conditions of test-area. The atmospheric products from MODIS can be used to defining the input data (like aerosol optical thickness, water vapor contents and ozone contents) for the atmospheric correction systems of AVHRR/NOAA images / Mestrado / Planejamento e Desenvolvimento Rural Sustentável / Mestre em Engenharia Agrícola
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Air pollution and adverse health effects: Assessing exposure windows and sensitivity to modeling choicesHe, Mike Zhongyu January 2020 (has links)
Air pollution is one of the leading environmental problems of the 21st century, and the rise of global urbanization has increasingly exacerbated air pollution’s public health impact. Existing epidemiologic studies have tackled the relationship between air pollution and health from a variety of perspectives, but many areas of research remain lacking, including studies originating from developing countries, the assessment of exposure windows and sensitivity of modeling choices, and a better understanding of the climate change impacts on air pollution and health. In this dissertation, I address all of the issues mentioned above. Chapter 1 formally introduces the topics of this dissertation and summarizes background information on several major air pollutants. It then provides an overview of existing research on air pollution epidemiology and describes key knowledge gaps. In Chapter 2, we conduct a systematic review of the scientific literature for data on fine particulate matter (PM2.5) in China, where historical PM2.5 data are not widely available prior to 2013. Using the 574 PM2.5 measurements we identified from the literature, we detected differences in PM2.5 levels across both geographic and economic regions of China. In Chapter 3, we investigate the associations between short- and intermediate-term exposure of nitrogen dioxide (NO2) and mortality in 42 counties in China from 2013 to 2015, and find evidence of significant associations up to seven days prior to exposure. In Chapter 4, we investigate the association between PM2.5 and hospitalizations in New York State using five separate exposure datasets from 2002 to 2012. We find that despite some fluctuations in effect estimates, the majority of models yielded consistently significantly harmful associations. In Chapter 5, we utilize a global chemistry-climate model to project ozone levels in 2050 under a variety of emissions scenarios and quantify the mortality impact associated with changes in ozone concentrations between 2015 and 2050 according to each scenario. We find that under climate change alone and adherence to current legislation, ozone-related deaths would increase. However, under a best-case scenario of maximum technologically feasible reductions in emissions, over 300,000 premature deaths related to ozone can be avoided. Finally, Chapter 6 summarizes the findings of this dissertation and discusses potential directions in future research. While much work remains to be done, this dissertation work takes an important step forward in closing existing knowledge gaps in the field of air pollution epidemiology. More importantly, we hope that our work sends a strong public health message on the importance of continuing research on air pollution and health.
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A study of tracer transports by planetary scale waves in the MIT stratospheric general circulation model.Moore, Gary Edward January 1977 (has links)
Thesis. 1977. M.S.--Massachusetts Institute of Technology. Dept. of Meteorology. / Microfiche copy available in Archives and Science. / Bibliography : leaves 62-65. / M.S.
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