Thesis (M. Sc)--York University, 2000. Graduate Programme in Physics and Astronomy. / Typescript. Includes bibliographical references (leaves 128-135). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://wwwlib.umi.com/cr/yorku/fullcit?pMQ59206.

The aim of this thesis is to describe the complete view of protection of the ozone layer. Therefore, it contains information about international, european and national legislation in this area. In addition, international legal aspects of climate change are mentioned. Finally, both ozone regime and climate change regime are compared. The author pays attention to the advantages and disadvantages of legal instruments and tries to find ways how to use ozone legal instruments in climate protection.

Ozone in indoor environments can pose a health risk to human occupants; around half of exposure to this pollutant occurs inside buildings. One approach to reducing indoor O3 levels is to mitigate O3 as it enters a building via outdoor air ventilation supply. Often, mechanical systems that introduce outdoor air into buildings are placed on building rooftops. At the urban scale, greenery has been shown to reduce levels of some harmful pollutants, including ozone and cities like Portland, OR, are mandating green roofs be built on large commercial buildings to increase urban green surfaces. We investigate if rooftop vegetation may act as a sink for O3 as transport occurs across a green roof. It is known that O3 can react with vegetated surfaces and the ground but there is scant empirical research on said pollutant dynamics on vegetated green roofs, and little data concerning pollutant interactions occurring on other rooftop designs. Essentially unstudied is the potential of rooftop designs to affect local concentrations of pollutants where building outdoor air supply may be co-located. In this study, we investigate O3 dry deposition using resistance uptake theory in an area that includes a green roof on a local big box retail store through a field study conducted during a two-week period in the Summer of 2017. Deposition velocities and subsequently surface resistances were measured. The 10th, 50th, and 90th percentiles for resistances were 54.8 s/m, 195.3 s/m, and 3692.9 s/m respectively. A 2-D advection-diffusion model of rooftop deposition is employed to describe transport across the green roof and sensitivity analysis was performed to compare the impact of different parameters. The sensitivity analysis demonstrated that the fetch length and the vegetation height had the biggest impact, followed by the meteorological parameters; the friction velocity and heat flux. The surface resistance had the least impact on deposition. An ideal case was used to demonstrate that even when conditions are maximized for deposition, the impact on the concentration gradient is minimal at best.

Resumé: Protection of the ozone layer of the Earth from the perspective of law This thesis is dealing with protection of the ozone layer. I chose this topic because I consider ozone layer as a very important folder of the environment and its weakening is of global nature and for its protection it was necessary to involve as many countries as possible. This work is focused mainly on the development of ozone layer protection at the international level and on current legislativ. It also includes the European Union's approach to this problem. In the beginning of my thesis I'm trying to explain what is ozone, which substances deplete the ozone layer and which principles and tools are used for its protection. Chapter two is dedicated to the development of ozone layer protection. It includes the beginnings of the international cooperation which began to take shape in the middle of the 70s when was published the first scientific work, which pointed to damage of ozone layer by halogenated hydrocarbons. International cooperation resulted to the adoption of the Vienna Convention for the Protection of the Ozone Layer and later to its implementation protocol - Montreal protocol, in September of 1987. The Montreal Protocol was considered an exceptional success of diplomacy in the sphere of environmental protection but in...

As modern life develops, humans spend most of their time inside buildings. Understanding the effects of different building materials that exist indoors on indoor air quality is crucial to ensure comfort, health, and productivity of building occupants. Indoor air quality (IAQ) is an important field of building science that focuses on studying the existence of different compounds indoors. These compounds include: airborne particles such as dust, volatile organic compounds (VOCs) such as carbonyls, reactive gases such as radon, ozone and others. Ozone is a strong oxidant gas that has adverse effects on human health, and is highly reactive with building materials that exist indoors. This reaction may reduce its concentration indoors, but may produce other by-products that could be more harmful for human health than ozone itself. In this dissertation, ozone reaction with different building materials is investigated in four studies. The first includes studying the effect of indoor carpet fiber type on ozone removal and carbonyl emissions. This study provides valuable data and knowledge about the importance of selecting carpet type and its effect on indoor environment. In the second study, different indoor plants were tested to evaluate their ability to remove ozone. The results from this study show wide variation between plants tested on ozone removal. Also, the ability of plants as ozone removal agent changes as light levels change. The third part studies ozone removal efficiency of HVAC filters previously installed in air handling units located on green and white membrane roofs of a commercial building. Detailed filter surface analysis using scanning electron microscope (SEM) was performed to understand the nature of deposits on these filters. The reason for differences in ozone removal efficiency of two filters in comparison with new filter is also discussed. The fourth study investigated ozone removal and carbonyl emissions from three different VOC content indoor latex paints. The outcomes from this research show that zero VOC latex paint has the most ozone effective removal capacity and this paint is the least carbonyl emitter. The research presented in this dissertation adds new data, valuable knowledge, and expands the understanding of the importance of selecting indoor materials to raise indoor air quality and make the buildings' indoor environment healthier and safer.

Halogen chemistry plays an important role in spring time ozone and mercury depletion events (ODEs and MDEs) and may efficiently oxidize hydrocarbons such as the important greenhouse gas methane (CH4) in the polar marine boundary layer. This thesis presents a detailed study of bromine and chlorine chemistry in the Arctic boundary layer based on measurements of bromine and chlorine containing species using chemical ionization mass spectrometry (CIMS). The capability of CIMS to accurately measure bromine oxide (BrO) was demonstrated. The first direct measurements of hypobromous acid (HOBr) were achieved. Conditions that likely favor bromine activation (e.g. high wind speeds) was presented. To advance the understanding of bromine recycling, a time dependent model was built to simulate the bromine speciation. Unexpected high levels of molecular chlorine (Cl2) were observed at Barrow, AK, which had a large impact on methane oxidation and could contribute to ozone loss and mercury oxidation at Barrow, AK. Moreover, BrO levels observed at Summit, Greenland did not explain the under prediction of hydroxyl radical (OH). However, the enhanced OH was found to be coincident with elevated reactive gaseous mercury (RGM). In addition, airborne BrO measurements were found to be generally consistent with airborne observations of soluble bromide based on the response factors of mist chamber to the bromine species and bromine chemical mechanisms.

107 Summary The Ozone layer of the Earth located in the stratosphere in an altitude of 20 to 50 kilometres is the important part of the gases surrounding the planet Earth. Its purpose is to absorb UV radiation that otherwise very negatively affects life on the Earth. During the twentieth century, this ability was weakened by the emission of substances proven much later to be very dangerous in this way. Until 1987, by various chemical reactions, in particular of chlorine atoms, the ozone hole has been formed over the South Pole of the Earth, not fully healed yet. In 1985, risk to human life led using the precautionary principle to the adoption of the Vienna Convention and subsequently of its implementing protocol including specific obligations especially the control measures of the production and consumption of ozone depleting substances and of the trade with them in 1987. The protocol was later modified by amendments and adjustments. This diploma thesis describes these acts with respect to their evolution and actual state of knowledge. At European level, it shows the evolution of the European environmental law in focus on the protection of the ozone layer and on the process of incorporation of international instruments in this area of environmental law. It describes these European acts and compares the...

Climate change and ozone depletion are topical challenges the world over and are both attributed mainly to human activities, particularly emissions of ozone depleting substances (ODSs). One such substance is chlorodifluoromethane (HCFC-22), a cheap, widely used refrigerant with a high global warming potential of 1780. Botswana is a signatory to the Montreal Protocol (MP), which guides international efforts to phase-out HCFC-22 and requires signatories to develop and implement a country-level Hydrochlorofluorocarbon Phase-out Management Plan (HPMP). This study, which used a mixed methods approach, was conducted to evaluate the phase-out of HCFC-22 management strategies and their environmental and socioeconomic implications in Botswana. A census of nine HCFC-22 importing companies was conducted and probability sampling proportional to size was used to select a sample of 159 respondents from the Department of Meteorological Services, HCFC-22 importers, customs officers from 20 purposively selected Botswana entry ports and HCFC-22 consumers from the importing companies. Category-specific respondent questionnaires and interview guides, site visits and assessment of records were used to gather data. Of particular interest were the annual HCFC-22 importation figures for each company, the Botswana Unified Revenue Services and the National Ozone Unit, as well as the level of compliance of the companies’ HCFC-22 phase-out management practices with relevant national regulations, the Botswana HPMP and the MP resolutions. Botswana’s HCFC-22 importers were found to be moderately to highly compliant to nonregulatory elements rather than regulatory elements. Overall, HCFC-22 consumption decreased from the baseline to 10.5% for the first stage (2013-2015), which was slightly more than the 10% reduction expected. A steady decrease in HCFC-22 consumption was noted towards the 35% target for 2020, largely due to awareness-raising initiatives directed at the surveyed stakeholders. Absolute HCFC-22 consumption dropped by approximately 510400 kgs from 2011-2017 or 28072 ozone depleting potential saved. On the downside, gaps were identified in the industry-wide quota-system, data reporting, prevention of illegal ODS trade, service technician training, user knowledge of alternatives and disposal of ODS equipment. The study recommends the use of a planning, policy formulation and implementation framework that integrates and balances three fundamentals, namely, stakeholder involvement, the process and the plan enablers.