Thesis (Ph. D.)--University of Chicago, Dept. of Geophysical Sciences, August 1999. / Includes bibliographical references. Also available on the Internet.

A fast response chemiluminescent ozone sonde originally intended for use as a balloon borne instrument, was deployed on a single engine light aircraft to determine mean ozone concentrations in the boundary layer downwind of a major urban centre. Vancouver is a coastal city at the mouth of a major river delta and valley walled in by mountains to the north and east. Hence, the pollutant distribution during anti-cyclonic conditions is influenced by the thermally induced flows of the sea/land breeze and mountain/valley wind systems. This study focused on ozone concentration in a steep walled, glacial valley near the city, where ozone concentrations had not been previously monitored but were suspected to be high. Measurements confirmed this hypothesis and the mass budget of ozone for the valley was calculated for a period shortly after sunrise when the rate of boundary layer growth was at its maximum. The high levels of ozone found in the valley were partly attributed to residual layer storage of ozone above the nocturnal stable layer. This overnight storage of ozone during sustained anti-cyclonic conditions suggests that the Pitt River valley and possibly other tributary valleys represent an important net sink for ozone emanating from precursor sources in the Lower Fraser Valley. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate

Abstract Not Provided / Thesis / Master of Arts (MA)

The purpose of this study was to investigate preservice science teachers&rsquo / mental models about the role and distribution of ozone layer and ozone layer depletion regarding their ontological orientation. This study was conducted with twenty four preservice science teachers who were enrolled in Elementary Science Education Program of Education Faculty of one public university located in Central Anatolia. From each grade level six preservice science teachers were selected / two from low achiever, two from middle achiever and two from high achiever. Moreover, in the study, data were collected by using semi structured interview and interview consists of eleven questions and with five questions having multiple parts. Interview recordings were transcribed and analyzed qualitatively. In the following steps of the analysis, researcher proceeded with the already formed and described codes in an easygoing way. The results revealed that preservice science teachers&rsquo / responses were mostly seen as skin cancer and sunburn as harmful effects of ultraviolet rays and preservice science teachers&rsquo / responses were mostly seen as activation vitamin D and photosynthesis of plants as beneficial effects of Sun&rsquo / s rays. Half of preservice science teachers thought that ozone layer exists in the atmosphere. Moreover, preservice science teachers&rsquo / responses were mostly seen as perfume, deodorant, car, and spray as harmful materials to ozone layer. Chlorofluorocarbon, carbon monoxide, and carbon-dioxide were the most seen responses as harmful chemicals to ozone layer. Similar misconceptions were identified when compared with past studies. Also, different misconceptions were found in the study. Ten distinct models were formed regarding role and distribution of ozone layer and five distinct models were formed regarding ozone layer depletion. Moreover, absorbing and reflecting surface was mostly seen ontological belief regarding role and distribution of ozone layer. Hole was mostly seen ontological belief regarding ozone layer depletion. Generally, achievement and grade level did not make difference among preservice science teachers forming which type of mental models and having ontological beliefs.

Measurements by the TOMS instrument aboard the Nimbus 7 satellite, of total column ozone over polar regions have been studied to determine the effects of solar induced natural ozone modulation. Two different analysis methods were employed to ascertain short term (days to months) and long term (months to years) solar influences on polar ozone. Bursts of intense solar activity can result in solar proton events (SPE's). The high energy protons, originating in solar flares, produce secondary electrons which can generate large concentrations of odd nitrogen in the middle atmosphere. These reactive species can catalytically destroy ozone. Three case studies are presented in an attempt to quantify the effect of SPE's on ozone mass over a latitude region 90 to 70°. In order to monitor the ozone response following a SPE over both hemispheres simultaneously, the SPE must occur during the equinox period when both poles are irradiated. Fortuitously, a SPE was recorded in March 1989, the analysis of which forms a case study in this thesis. Ozone depletions of 7.4 x 10 to the power of 9 kg for the south polar cap and 8.0 x 10 to the power of 9 kg for the north polar cap indicate the degree of symmetry for this event. Longer term effects of solar variability are investigated by Fourier techniques. A Fourier transform of eleven years of total ozone mass values, over the region 90 to 70° S, was performed. Inspection of the Fourier spectrum reveals peaks associated with solar cycle, annual and semi-annual oscillations, that may be attributed directly to solar variation. Other peaks, corresponding to QBO and ENSO periodicities, may be ascribed to indirect solar influences i.e. thermally driven dynamics. Finally, a comparison between the phase of the solar cycle peak in this spectrum with that in a spectrum of daily values of solar radio flux, reveals that the austral polar ozone solar cycle periodicity lags solar forcing by 2.8 years. Portions of chapters have been reported at the 1990 South African Institute of Physics Annual Conference, University of Port Elizabeth, South Africa and as a poster at the 1992 Quadrennial Ozone Symposium, Charlottesville, United States of America, 4-13 June 1992. In addition, various parts of this work has been submitted for publication, viz: Stephenson, J. A. E. and M. W. J. Scourfield, Importance of energetic solar protons in ozone depletion, Nature, 352, 137: 1991. / Thesis (Ph.D.)-University of Natal, Durban, 1994.

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...

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.

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.

The Antarctic climate has undergone complex changes over the last fifty years, driven largely by stratospheric ozone depletion. By the end of this century, under the current trajectory of anthropogenic emissions, the climate of Antarctica is projected to be significantly wetter, warmer and prone to the collapse of ice shelves and loss of sea ice cover. The overarching aim of this thesis is to increase our understanding of recent and projected Antarctic climate change and its drivers. We also investigate the potential global implications of these changes and show that the effects will not be limited to the southern high latitudes. In the first half, we investigate the drivers of Antarctic climate change over the observational period. Specifically, we study the influence of the stratosphere on the southern high latitude surface climate, through stratosphere-troposphere dynamic coupling as well as stratospheric ozone depletion. We examine the impact of these on the Amundsen Sea Low, a key circulation feature near West Antarctica. We demonstrate using reanalysis that stratospheric heat flux extremes are linked to high latitude tropospheric anomalies in the Amundsen Sea region. During extreme negative (positive) events there is a westward (eastward) shift of the Amundsen Sea Low, a warming (cooling) and increase (decrease) of geopotential height over the Amundsen and Bellingshausen Seas. We find that most CMIP5 models are not able to capture this relationship. Next, we demonstrate that, since 1965, stratospheric ozone depletion has acted to deepen the Amundsen Sea Low in austral summer by 1 hPa per decade. This result was consistent across two different comprehensive climate models, each with very different model physics and climate sensitivity. It must be noted that the ozone depletion signal on the Amundsen Sea Low is small compared to the internal climate variability in this region. Using ensembles of model integrations and analysing them over the full period of ozone depletion (which started a couple of decades before the satellite era) is necessary to detect a robust signal. In the second half, we investigate the effects of future Antarctic climate change, specifically the effects of projected sea ice loss over the coming century. Climate model simulations are used to isolate the effect of end-of-the-century Antarctic sea ice loss which is compared and contrasted with the effects of projected Arctic sea ice loss. We first study the effects of projected Antarctic sea ice loss used atmosphere-only simulations. As for the Arctic, results indicated that Antarctic sea ice loss will act to shift the tropospheric jet equatorward, an internal negative feedback to the poleward shift associated with increased greenhouse gases. Antarctic sea ice loss is shown to have an important effect throughout the year whereas Arctic sea ice loss will have more seasonally varying impacts. Building upon these results we the use the same climate model but in a fully coupled setup to study the effects of projected Antarctic sea ice loss on the climate system. We show that both Arctic and Antarctic sea ice loss will have important global effects, causing a ‘mini global warming’ signal. The tropical response to Antarctic sea ice loss is shown to be remarkably similar to that of Arctic sea ice loss, with enhanced warming in the Eastern Tropical Pacific and increased precipitation throughout much of the equatorial Pacific. These results highlight how intimately coupled the Antarctic climate is to the rest of the climate system.

O presente trabalho tem como objetivo investigar os processos de ascensão e queda dos clorofluorocarbonetos (CFCs) como bens de consumo, bem como o desenvolvimento da percepção de risco da comunidade química em relação a esses compostos, que culminou com sua caracterização como agentes de risco ambiental global. Para isso, foi desenvolvido um estudo de caso histórico acerca do uso dos CFCs ao longo do século XX, de solução tecnológica ideal a protagonista de uma inédita dimensão de risco químico. Além disso, foi realizada uma análise de cartas enviadas por leitores, editoriais e resenhas de livros publicadas em cinco periódicos científicos: Chemical & Engineering News, Journal of Chemical Education, Environmental Science and Technology, Nature e Science, no período compreendido entre 1975 e 1991, e de livros didáticos de Química Ambiental publicados entre 1970 e 1995 - período marcado por intenso debate sobre a possibilidade de destruição da camada de ozônio estratosférica. A escolha desses periódicos e livros buscou contemplar diferentes seções da comunidade química, de modo a se ter uma amostra representativa de diferentes formas de pensamento dentro desse amplo espectro profissional que constitui a química. Para análise dessa amostra foi escolhida a Teoria Cultural de Douglas e Wildavsky, a qual descreve quatro visões de mundo que se mostram bastante adequadas para analisar as percepções de risco, as atitudes e os argumentos envolvidos nas discussões da época. Os resultados obtidos apontam para mudanças nas percepções de risco da comunidade química, aproximando-as do Princípio da Precaução para a tomada de decisões, em um período marcado pelo desenvolvimento da Química Ambiental. / This study aims to investigate the processes of rise and fall of chlorofluorocarbons (CFCs) as consumer goods, as well as the development of risk perception regarding these compounds among the chemists community, culminating in its characterization as agents of global environmental risk. A historical case study on the trajectory of CFCs throughout the twentieth century, from ideal technological solution to protagonist of an unprecedented scale chemical risk, was developed. In addition, the study includes an analysis of letters from readers, editorials and book reviews published in five journals: Chemical & Engineering News, Journal of Chemical Education, Environmental Science and Technology, Nature and Science, in the period between 1975 and 1991, and also an analysis of Environmental Chemistry textbooks published between 1970 and 1995 - a period marked by intense debate about the possibility of destruction of the stratospheric ozone layer. The choice of these journals and books sought to include different sections of the chemistry community, in order to get a representative sample of different ways of thinking within the broad professional spectrum of chemistry. Douglas\' and Wildavsky\'s Cultural Theory was selected to analyse this sample. The theory describes four worldviews that seems rather appropriate to analyze risk perceptions, attitudes and arguments involved in the discussions of the time. Results point to changes in chemists\' risk perceptions, which brought them closer to the Precautionary Principle as a guide to decision making in a period marked by the development of Environmental Chemistry.