Dissertations / Theses on the topic 'Greenhouse effect, atmospheric'
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Schultz, Lisa. "Understanding the Greenhouse Effect Using a Computer Model." Fogler Library, University of Maine, 2009. http://www.library.umaine.edu/theses/pdf/SchultzL2009.pdf.
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Li, Chi-cheong Markus. "The trading of greenhouse gas." Click to view the E-thesis via HKUTO, 2000. http://sunzi.lib.hku.hk/hkuto/record/B42575485.
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Li, Chi-cheong Markus, and 李志昌. "The trading of greenhouse gas." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B42575485.
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McKee, Ian Fraser. "Plant physiological and growth responses to elevated concentrations of atmospheric COâ†2." Thesis, University of Cambridge, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.241094.
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Rochefort, Line. "Atmospheric COâ†2 and environmental determinants of plant growth : a model with Sinapis alba L." Thesis, University of Cambridge, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240047.
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O'Donnell, Chris. "The response of Avena fatua to the enhanced greenhouse effect /." [St. Lucia, Qld.], 2002. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe17124.pdf.
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Pipatti, Riitta. "Emission estimtes for some acidifying and greenhouse gases and options for their control in Finland /." Espoo : Technical Research Centre of Finland, 1998. http://www.vtt.fi/inf/pdf/publications/1998/P340.pdf.
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Manning, Gregory A. "An apparatus to investigate photon induced gaseous reactions using Fourier transform infrared spectroscopy /." free to MU campus, to others for purchase, 2000. http://wwwlib.umi.com/cr/mo/fullcit?p9974659.
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Nettleton, Stuart John. "Benchmarking climate change strategies under constrained resource usage /." Electronic version, 2009. http://utsescholarship.lib.uts.edu.au/iresearch/scholarly-works/handle/2100/1012.
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Webb, Leanne Beryl. "The impact of projected greenhouse gas-induced climate change on the Australian wine industry /." Connect to thesis, 2006. http://eprints.unimelb.edu.au/archive/00003030.
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Kelly, Geoffrey. "National policy choices for an international problem case studies in greenhouse policy /." Access electronically, 2008. http://ro.uow.edu.au/theses/86.
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Denari, Gabriela Bueno. "Relação entre complexidade e história da ciência : contribuições a partir do tema efeito estufa na análise de um curso de formação /." Bauru, 2019. http://hdl.handle.net/11449/182146.
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Orientador: João José CaluziBanca: Cibelle Celestino Silva
Banca: Deividi Marcio Marques
Banca: Silvia Regina Quijadas Aro Zuliani
Banca: Marcelo Carbone Carneiro
Resumo: As questões ambientais estão cada vez mais sendo discutidas na sociedade. Contudo, de acordo com o autor francês Edgar Morin, para entendê-las em completude, é preciso ter uma mudança de percepção de mundo, buscando religar os pensamentos que foram fragmentados ao longo dos séculos, tanto no contexto social como no educacional. Mudar o pensamento não é um processo trivial e a História da Ciência (HC) pode ser uma boa ferramenta para os estudos da complexidade, possibilitando melhor compreensão sobre as visões contemporâneas da ciência e suas consequências em assuntos amplamente discutidos. Frente aos debates ambientais, foi escolhido como motivação das discussões da presente tese o tema efeito estufa intensificado e suas consequentes alterações no clima. Há pesquisas que relacionam o pensamento complexo com o ensino de ciências e a HC com ensino, mas são quase ausentes as que proponham ou investiguem conexões entre a tríade complexidade, HC e ensino. Diante da suposição de que a HC pode auxiliar a desenvolver o pensamento complexo, o objetivo do trabalho foi identificar a possível relação entre os princípios da complexidade de Edgar Morin e categorias de HC a partir dos estudos do efeito estufa intensificado - na teoria e com estudantes em cursos de formação docente. Foi utilizada a pesquisa qualitativa para o desenvolvimento da tese em duas etapas: a primeira - chamada de estudos teóricos - foi importante para dar base para as discussões na segunda etapa - denominada ativida... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Environmental issues are increasingly being discussed in society. However, according to French author Edgar Morin, in order to understand them in completeness, it is necessary to have a change of world perception, seeking to reconnect the thoughts that have been fragmented over the centuries, both in the social and educational context. Changing thinking is not a trivial process and the History of Science (HS) can be a good tool for studying complexity, enabling a better understanding of contemporary views of science and its consequences on widely discussed subjects. In the face of environmental debates, the intensified greenhouse effect theme and its consequent changes in climate were chosen as motivation of the discussions of this thesis. There is research that links complex thinking with science teaching and HS with teaching, but there are almost no ones who propose or investigate connections between the triad complexity, HS and teaching. Given the assumption that HS can help to develop complex thinking, the objective of this work was to identify the possible relationship between the principles of complexity of Edgar Morin and HS categories from studies of the intensified greenhouse effect - in theory and with students in teacher training courses. Qualitative research was used for the development of the thesis in two stages: the first - called theoretical studies - was important to provide the basis for the discussions of the second stage - called activities with licensees.... (Complete abstract click electronic access below)
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Goldthorpe, Ward Hilary. "Carbon capture and storage and the Australian climate policy framework. /." Connect to thesis, 2009. http://repository.unimelb.edu.au/10187/7058.
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Avise, Jeremy Charles. "Global change and regional air quality impacts of climate, land-use, and emissions changes /." Online access for everyone, 2007. http://www.dissertations.wsu.edu/Dissertations/Fall2007/J_Avise_120907.pdf.
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Leung, Wai-hung. "Global climate change : environmental implications for Hong Kong /." Hong Kong : University of Hong Kong, 1996. http://sunzi.lib.hku.hk/hkuto/record.jsp?B17457294.
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施錦杯 and Kam-pui Sze. "Effects of the interaction of atmosphere and ocean on humanactivities." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1999. http://hub.hku.hk/bib/B31254378.
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Sze, Kam-pui. "Effects of the interaction of atmosphere and ocean on human activities /." Hong Kong : University of Hong Kong, 1999. http://sunzi.lib.hku.hk/hkuto/record.jsp?B21301414.
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Bostrom, Gregory A. "Development of a Portable Cavity Ring-Down Spectroscopic Technique for Measuring Stable Isotopes in Atmospheric Methane." PDXScholar, 2010. https://pdxscholar.library.pdx.edu/open_access_etds/51.
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Trace gases can have a significant impact on the Earth's climate, and the analysis of changes in these gases and an understanding of how much of these changes are a result of human activity is important for understanding global climate change. Methane (CH4) is the second only to CO2 in radiative forcing over the last 200 years, and its concentration in the atmosphere has more than doubled since 1750. Sources and sinks of CH4 have characteristic isotopic effects, which shift the relative concentration of the methane isotopologues. Spectroscopic techniques for of analysis the isotopic composition of methane have been evolving since the early 1990's, and promise real-time, in-situ measurements that would provide unprecedented information on the methane atmospheric cycle. Here we present our development and results of a new optical spectroscopic isotope ratio instrument using cavity ringdown spectroscopy in the near IR region using the ν2+2ν3 overtone band. This region has limited interference from other molecules, and an advantageous juxtaposition of a 13CH4 triplet, and a single 12CH4 peak, allowing near-simultaneous measurement of both isotopologues. We present the results of two datasets showing high linearity over a wide range of isotope ratios, which achieved a precision of ±4 /. We present analysis of the data and consider the effects of temperature and molecular interference.
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Shafer, Sarah L. "Potential vegetation response to future climate change in western North America and its implications for biological conservation and geographical conceptualizations of place /." view citation or download file of text, 2000. http://wwwlib.umi.com/cr/uoregon/fullcit?p9986759.
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Thesis (Ph. D.)--University of Oregon, 2000.Typescript. Includes vita and abstract. Includes bibliographical references (leaves 132-150). Also available for download via the World Wide Web; free to University of Oregon users.
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Assunção, Marcelo Henrique Correa. "Emissões de gases do efeito estufa em sistemas multitróficos de aquicultura /." Jaboticabal, 2017. http://hdl.handle.net/11449/150932.
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Orientador: Tadeu de Siqueira BarrosCoorientador: Wagner Cotroni Valenti
Banca: Antonio Fernando Monteiro Camargo
Banca: Lúcia Helena Sipaúba Tavares
Banca: Matheus Nicolino Peixoto Henares
Banca: Irineu Bianchini Junior
Resumo: O objetivo deste estudo foi investigar o fluxo de gases do efeito estufa (GEE) em viveiros de criação de organismos aquáticos. Nós testamos se o uso de sistemas multitróficos e multiespaciais (IMTA), povoados com lambari-do-rabo-amarelo (Astyanax lacustris) e camarão-da-amazônia (Macrobrachium amazonicum) numa região tropical, altera o fluxo de gases do efeito estufa em comparação com um sistema de monocultivo de A. lacustris. Nós desenvolvemos um experimento em viveiros de fundo natural com três tratamentos e quatro réplicas: monocultivo (Tetra), IMTA livre (Free IMTA) e IMTA tanque rede (Cage IMTA). O experimento durou 68 dias, entre os meses de novembro e janeiro de 2016. Nós mensuramos os fluxos de dióxido de carbono (CO2), metano (CH4) e óxido nitroso (N2O) por meio das metodologias difusiva e dissolvida. A média dos fluxos na metodologia difusiva foi de -8.93 mg.m-2.h-1 para o CO2, -0.88 mg.m-2.h-1 para o CH4 e 1.78 mg.m-2.h-1 para o N2O. A concentração de CO2 variou de 0.0481 a 0.6668 mg.L-1, CH4 de 0.0003 a 0.0053 mg.L-1 e N2O de 0.0789 a 0.1177 mg.L-1. Nossos resultados indicam variação ao longo do tempo, com maior fluxo de GEE no início do experimento, diminuição ao longo do período de cultivo e tendência de neutralidade com relação a emissão de GEE no final do período experimental.
Abstract: The aim of this study was to investigate Greenhouse Gases (GHG) fluxes in aquaculture ponds. We tested if the use of Integrated Multi Trophic Aquaculture (IMTA) with Yellow tail tetra (Astyanax lacustris) and Amazon River prawn (Macrobrachium amazonicum) in a tropical environment changes the GHG flows in comparation with A. lacustris monoculture. We developed an experiment in earthen ponds with three treatments and four replications: monoculture (Tetra), two species free in the pond (Free IMTA) and fishes in cage and prawns free (Cage IMTA). Experiment ran 68 days between November and January 2016. We measured fluxes of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) with diffusive and dissolved methodologies. Mean of diffusive fluxes was -8.93 mg.m-2 .h-1 for CO2, -0.88 mg.m-2 .h-1 for CH4 e 1.78 mg.m-2 .h-1 for N2O. Concentration of CO2 oscillated between 0.0481 and 0.6668 mg.L-1, CH4: 0.0003 and 0.0053 mg.L-1 e N2O: 0.0789 a 0.1177 mg.L-1 . Our results indicate variations over time, with higher fluxes at the beginning of experiment, decreasing over the growing period and trend of neutrality regarding to the GHG emissions at the end of experimental period.
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Kurup, Premnadh M. "Secondary students beliefs about, understandings of, and intentions to act regarding the greenhouse effect." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2003. https://ro.ecu.edu.au/theses/1324.
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The greenhouse effect (GHE) is a concern to everyone on this planet. To understand the GHE, students and citizens need an understanding of the chemical processes underlying this environmental phenomenon. Citizens need to be scientifically literate in relation to this phenomenon in order to participate in democratic decision-making and to take appropriate actions in their daily lives. As the GHE is a global issue it will require collective and individual actions to prepare for the likely climatic changes and to reduce the further impact of the GHE. This study focused on high school students' beliefs about, understandings of the GHE and their intentions to act in ways that would reduce greenhouse gas emissions. Aspects of the GHE that are taught in high school science were also investigated. The study was conducted in five schools each in Western Australia (Australia) and Kerala (India) and data were collected from 438 Year 10 and 12 students representing compulsory and post-compulsory stages of education in both states. Two hundred and thirteen students from Western Australia and 225 students from Kerala completed a questionnaire and a sample of students and heads of science were interviewed. A Propositional Knowledge Statement (PKS) was developed, which is a set of propositions that outline science concepts necessary for an understanding of the GHE in terms of its causes, effects, mechanism and actions that can be taken to reduce greenhouse gas emission. In this study the PKS is considered to be the essential knowledge necessary to interpret the GHE, to take appropriate environmental action, and to make informed decisions as a scientifically literate member of society. The questionnaire and interviews were based on the PKS. The study revealed that high school students strongly believe that the GHE is real and affecting the climate at present and will also affect it in the future. They consider that the GHE is a relatively important social issue and they believe that governments should conduct programmes to raise community awareness and enact strict laws to reduce the release of greenhouse gases. Students' understanding of the GHE is inadequate to make informed decisions and take appropriate environmental actions as a scientifically literate member of society. The majority of students and their families are already taking or are considering taking 10 accepted actions to reduce greenhouse gas emissions by household activities. The majority of students are not prepared to sacrifice their personal comforts or conveniences to reduce greenhouse gas emissions and they have strong reasons for that, however, they believe that governments should enact strict laws to reduce greenhouse gas emissions and should sign the Kyoto protocol. The GHE is not adequately represented in Western Australian and Kerala science and chemistry curricula. The heads of school science departments in Western Australia and Kerala consider that school science should do more to teach the GHE, as it is an important aspect of scientific literacy. An ideal scenario for students’ beliefs about, understanding of the GHE and commitments to take action that would enable individuals and communities to reduce greenhouse gas emission was developed based on the PKS and reports such as lPCC (2001), UNEP (2001), AGO (1999; 2000) and UN (1992). The actual scenario was based on the data from this study. The differences between ideal and actual scenarios were discussed and implications for improving education about the OHE were developed. Information about the curriculum and students' sources of information about the GHE, students' beliefs, understandings and intentions to act were mapped against the theory of reasoned action (Ajzen & Fishbein, 1980).
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Galbieri, Rodrigo 1977. "Potencial da intermodalidade rodo-ferroviaria na mitigação das emissões de CO2 : o caso do setor de transporte de cargas do estado de São Paulo." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/264884.
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Orientadores: Andre Felipe Simões, Arnaldo Cesar da Silva WalterDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica
Made available in DSpace on 2018-08-13T19:53:21Z (GMT). No. of bitstreams: 1 Galbieri_Rodrigo_M.pdf: 3587680 bytes, checksum: fcb9a6c8953f714eebba38de595cded9 (MD5) Previous issue date: 2009
Resumo: No ano de 2005, no Brasil, cerca de 58% das cargas foram transportadas através de rodovias, enquanto o modal ferroviário transportou apenas 26% das cargas. O desbalanceamento da matriz de transporte de cargas paulista é ainda mais crítica, pois cerca de 88,6% das cargas que circularam pelo Estado de São Paulo foram através de rodovias e apenas 9,5% através de ferrovias. Esse desbalanceamento em favor do modal rodoviário, mais energo-intensivo, causa inúmeros problemas econômicos, sociais e ambientais para o Brasil e para o Estado de São Paulo, destacando-se: maior consumo de combustíveis fósseis (óleo Diesel), conseqüentemente maiores índices de emissões de poluentes, frete mais caro e congestionamentos. Em relação ao Estado de São Paulo, o problema dos congestionamentos que atualmente já é grave, tende a piorar no médio e longo prazo, muito devido ao crescimento econômico e aumento das taxas de motorização. Tendo como base os estudos de implementação das obras de infra-estrutura do Plano Diretor da Secretária de Transportes do Estado de São Paulo (PDDT-Vivo 2000/2020), o principal objetivo desse Trabalho é mostrar o potencial em economia de combustível (óleo Diesel) e diminuição das emissões de CO2 que uma implementação efetiva da intermodalidade rodo-ferroviária no transportes de cargas dentro do Estado de São Paulo pode gerar. A economia de óleo Diesel pode chegar a mais de 6,89 milhões de m3 e as emissões evitadas de CO2 pode chegar a mais de 17,59 milhões de toneladas entre 2009 e 2029. Esse Trabalho analisa as características que um projeto envolvendo intermodalidade rodo-ferroviária deve possuir para conseguir aprovação no Executive Board da UNFCCC, a fim de se tornar um projeto ligado ao Mecanismo de Desenvolvimento Limpo, e também aborda as principais barreiras que o mesmo possa enfrentar.
Abstract: In 2005 about 58% of cargoes, in TKU, were transported from highways in Brazil; while the modal railway carried only 26% of cargo (PNLT, 2007). The imbalance of the São Paulo state's transportation matrix is even more critical: about 88.6% of the cargoes that circulated on this state used roads as means and only 9.5% of this transportation was made through railways. This imbalance in favor of the road model, more energy-intensive, causes many economic problems; social and environmental impacts for Brazil and for the Sao Paulo state. Namely, this causes higher consumption of fossil based fuels (Diesel), therefore causing higher rates of pollutants emissions. In addition, this kind of transportation is more expensive than the railway model and subjected to uncertainties such as traffic jams. In the São Paulo state, the traffic jams issue is currently quite severe and tends to get worse in the medium and long terms, mainly due to the economic growth and due to the increasing rates of motorization. Using as basis the studies for the infrastructure implementation, from the Master Plan of the Secretary of Transportation of the State of São Paulo, this work's main goal is to show the potential for fuel economy (Diesel) and therefore the reduction of CO2 emissions that can be accomplished by an effective implementation of the road-rail intermodal model within of São Paulo. The diesel economy can be more than 6.89 million m3, and the avoided CO2 emission may reach more than 17.59 million tons between 2009 and 2029. Also, this work discuss the necessary characteristics for a road-rail intermodal project to get the Executive Board of the UNFCCC approval, and the most common obstacles for such kind of project.
Mestrado
Mestre em Planejamento de Sistemas Energéticos
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Cantin, Danielle 1967. "Response of Pinus banksiana (Lamb.) families to a global change environment." Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=68159.
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We examined how fast- and slow-growing families (based on height at 10 years) of Pinus banksiana Lamb. are affected by a climate altered by CO$ sb2$ during their first growing season. Our primary objective was to evaluate the possibility that genotypes performing best under present conditions may not necessarily do best under projected warmer climate. Seedlings were grown for six months in two climatic environments (350 $ mu$L/L CO$ sb2$ x present temperatures and 700 $ mu$L/L CO$ sb2$ x 4$ sp circ$C warmer temperatures) and with 100 ppm and 5 ppm nitrogen.The CO$ sb2$T$ sp circ$ environment had a significant effect on most biomass components of seedlings and water-use efficiency but not on height and other growth variables. The nitrogen fertilization was generally the most significant effect of the treatments for most growth variables.
All the families responded in a similar way to variations in the growing environments except for WUE. Family differences were more important for measurements of height and growth variables than for biomass components. The architecture of seedlings was also highly variable between families. Norm of reaction graphs were built for several growth variables to outline which families were overall most successful in an enriched CO$ sb2$T$ sp circ$ environment. Of the 15 families studied, four of them were classified as most successful in a projected high CO$ sb2$T$ sp circ$ climate.
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Viúdez, i. Mora Antoni. "Atmospheric downwelling longwave radiation at the surface during cloudless and overcast conditions. Measurements and modeling." Doctoral thesis, Universitat de Girona, 2011. http://hdl.handle.net/10803/31841.
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Atmospheric downwelling longwave radiation is an important component of the terrestrial energy budget; since it is strongly related with the greenhouse effect, it remarkably affects the climate. In this study, I evaluate the estimation of the downwelling longwave irradiance at the terrestrial surface for cloudless and overcast conditions using a one-dimensional radiative transfer model (RTM), specifically the Santa Barbara DISORT Atmospheric Radiative Transfer (SBDART). The calculations performed by using this model were compared with pyrgeometer measurements at three different European places: Girona (NE of the Iberian Peninsula), Payerne (in the East of Switzerland), and Heselbach (in the Black Forest, Germany). Several studies of sensitivity based on the radiative transfer model have shown that special attention on the input of temperature and water content profiles must be held for cloudless sky conditions; for overcast conditions, similar sensitivity studies have shown that, besides the atmospheric profiles, the cloud base height is very relevant, at least for optically thick clouds. Also, the estimation of DLR in places where radiosoundings are not available is explored, either by using the atmospheric profiles spatially interpolated from the gridded analysis data provided by European Centre of Medium-Range Weather Forecast (ECMWF), or by applying a real radiosounding of a nearby site. Calculations have been compared with measurements at all sites. During cloudless sky conditions, when radiosoundings were available, calculations show differences with measurements of -2.7 ± 3.4 Wm-2 (Payerne). While no in situ radiosoundings are available, differences between modeling and measurements were about 0.3 ± 9.4 Wm-2 (Girona). During overcast sky conditions, when in situ radiosoundings and cloud properties (derived from an algorithm that uses spectral infrared and microwave ground based measurements) were available (Black Forest), calculations show differences with measurements of -0.28 ± 2.52 Wm2. When using atmospheric profiles from the ECMWF and fixed values of liquid water path and droplet effective radius (Girona) calculations show differences with measurements of 4.0 ± 2.5 Wm2. For all analyzed sky conditions, it has been confirmed that estimations from radiative transfer modeling are remarkably better than those obtained by simple parameterizations of atmospheric emissivity.La radiació infrarroja a l’atmosfera és una component important del balanç energètic del planeta; en estar fortament relacionada amb l’efecte hivernacle influeix de manera remarcable en el clima. En aquest estudi s’avalua la bondat de les estimacions de la irradiància infrarroja incident en superfície (DLR) fetes amb un model unidimensional de transferència radiativa, el Santa Barbara DISORT Atmospheric Radiative Transfer (SBDART), per a condicions de cel serè o bé completament ennuvolat. Els càlculs realitzats amb aquest model han estat comparats amb mesures de pirgeòmetre realitzades en tres emplaçaments a Europa: Girona (NE de la Península Ibèrica), Payerne (a l’est de Suïssa), i Heselbach (a la Selva Negra, Alemanya). Els estudis de sensibilitat fets amb el model de transferència radiativa han mostrat l’especial importància que tenen els perfils atmosfèrics de temperatura i contingut d’aigua en absència de núvols; per cels completament ennuvolats l’estudi de sensibilitat mostra que, a banda dels perfils atmosfèrics esmentats, l’altura de la base dels núvols és molt rellevant. S’ha estimat la DLR per indrets on no es disposava de radiosondatges, substituint-los bé per un radiosondatge proper, o bé per perfils interpolats espacialment en l’anàlisi del model de predicció meteorològica de l’European Centre of Medium-Range Weather Forecast (ECMWF). Els càlculs han estat comparats amb mesures per tots els llocs. Per condicions de cel serè, i quan es disposa de radiosondatge, els càlculs mostren una diferència amb les mesures de -2.7 ± 3.4 Wm-2 (Payerne). Quan no es disposa d’aquests perfils, la diferència entre les modelitzacions i les mesures és de 0.3 ± 9.4 Wm-2 (Girona). Per condicions de cel cobert, quan es disposa del radiosondatge i les propietats dels núvols (derivades a partir d’un algoritme que empra mesures espectrals en infraroig i en la banda de microones en superfície, Selva Negra), els càlculs mostren una diferència amb les mesures de -0.28 ± 2.52 Wm-2. Quan es fan servir els perfils del ECMWF i es fixa el valor de la columna d’aigua líquida i el radi efectiu de les gotes d’aigua (Girona) els càlculs mostren una diferència amb les mesures de 4.0 ± 2.5 Wm-2. També s’ha confirmat per totes les condicions estudiades que les estimacions amb el model de transferència radiativa són notablement millors que les obtingudes amb parametritzacions senzilles de l’emissivitat atmosfèrica.
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Ibrahim, Amr, and University of Lethbridge Faculty of Arts and Science. "Spectroscopic study of channel spectra phenomena in the synchrotron-based FTIR spectrometer at the Canadian Light Source." Thesis, Lethbridge, Alta. : University of Lethbridge, Dept. of Physics and Astronomy, c2010, 2010. http://hdl.handle.net/10133/2638.
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Recently, the high radiance of synchrotron sources was used to enhance FTIR
spectrometer performance. However, excessive channel spectra when synchrotron
sources are used degrade the quality of retrieved spectral parameters. In the
research reported in this thesis, seven different techniques for handling channel
spectra were investigated. These techniques were used to reduce channel spectra
for a test group of seven samples of CO2 mixed with air recorded using the
synchrotron source at the Canadian Light Source. The increases in signal to noise
ratio (SNR) of spectra handled with each technique were calculated. SNR results
showed that transmission spectra, produced using synthetic background spectra
with simulated channel spectra, achieved the highest SNR improvement. However,
when the spectra groups were fitted using nonlinear least square fit algorithm, the
technique using channel spectra fitting produced the smallest fitting residual.
Moreover, the retrieved intensities and air broadening coefficients of 21 spectral
lines showed that the spectral fitting technique produced the most accurate values
as compared to the HITRAN 2008 database. Although the spectral fitting technique
was accurate in retrieving spectral line parameters, applying the technique at wider
spectral ranges was less accurate.
A modification to the channel spectra fitting technique by performing
iterations of channel fitting was introduced to process wider spectral ranges.
Carbon dioxide laser band I centred at 961 wavenumber was analyzed using 24
spectra recorded under different experimental conditions. The intensity and air-and self-broadening coefficients were retrieved for 48 spectral lines with average
deviations from HITRAN database values of 2.11%, 1.25% and 4.14%, respectively,
using the Voigt profile. These average deviations lie within the uncertainty limits
listed by the database. The deviation between our results and other results reported
in the literature were also examined and it is found to be also within the range of
HITRAN uncertainties. The effect of errors in fitting channel spectra parameters was
examined and found to be mitigated by the inclusion of channel-free spectra in the
multispectral fit.xiv, 134 leaves : ill. ; 29 cm
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Lückemeyer, Alfonso Celso Arruda Bianchini. "Análise da matriz energética brasileira sob a visão sistêmica: programas energéticos governamentais e a redução de gases de efeito estufa." Universidade Tecnológica Federal do Paraná, 2010. http://repositorio.utfpr.edu.br/jspui/handle/1/188.
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Essa dissertação propôs como tema de estudo um panorama das energias renováveis e menos poluentes no Brasil, com enfoque para as mudanças climáticas globais, mais especificamente a emissão de gases de efeito estufa. O objetivo da pesquisa foi analisar a matriz energética brasileira no que se refere à relação entre a oferta de energia renovável, regulamentada pelas políticas e programas governamentais e a emissão de gases de efeito estufa. Esta análise foi realizada por meio de uma contextualização da matriz energética brasileira no panorama mundial, da relação entre os usos de energias com as mudanças climáticas globais e do estudo dos programas energéticos brasileiros e sua contribuição para minimizar a emissão de poluentes atmosféricos. Para o desenvolvimento deste estudo foi realizado um levantamento histórico, por meio de revisão bibliográfica, do uso da energia e de programas energéticos governamentais, da oferta de energia e emissões de CO2 e cenários para o ano de 2030, dos acordos internacionais e mecanismos para a mitigação de mudanças climáticas, dos setores da sociedade brasileira que mais consomem energia e quais as fontes utilizadas por esses setores, das tecnologias de energias renováveis disponíveis e os danos climáticos por elas causados nos processos energéticos. A ótica epistemológica sistêmica fundamentou essa dissertação, cujo método mostrou-se adequado ao encaminhamento da questão energética para o jogo de harmonização entre recursos naturais, consumo e danos climáticos, com base na visão de uma ecossocioeconomia. Como principais resultados verificou-se que é possível aumentar a participação de energias renováveis e menos poluentes tais como eólica, solar, PCH e biomassa na matriz energética brasileira e promover a eficiência energética de forma a aumentar a oferta de energia, diminuindo a necessidade da utilização de recursos energéticos naturais e os impactos ambientais decorrentes. Constatou-se que as políticas e programas energéticos governamentais contribuem para o incentivo do uso de energias renováveis e para a melhoria dos índices de poluentes atmosféricos. Concluiu-se que para mitigar a emissão de gases de efeito estufa a partir dos processos energéticos e simultaneamente garantir a continuidade do desenvolvimento econômico faz-se necessário um conjunto de medidas que inclua: a substituição gradativa de fontes fósseis na matriz energética por fontes renováveis, associada à eficiência energética e a programas governamentais integrados e viáveis em termos políticos, econômicos, tecnológicos e sócio-ambientais. Observou-se que há um jogo de forças envolvendo energia entre as necessidades sócio-ambientais e de desenvolvimento econômico e, portanto, no momento presente e para um futuro próximo não há como descartar a total utilização de energias não renováveis (termelétricas a combustíveis fósseis e a energia nuclear e combustíveis fósseis para o setor de transportes), tendo em vista a necessidade de se atender à questão da segurança energética.This thesis proposed as subject of study an overview of renewable and less pollutant energy in Brazil, focusing on global climate change, specifically the emission of greenhouse gases. The objective of the research is to analyze the Brazilian energy matrix with respect to the relation between the supply of renewable energy, regulated by governmental policies and programs, and the issue of greenhouse gases. This analysis is made through a contextualization of the Brazilian energy matrix in the world scene, of the relation between the uses of energy and global climate change, and of the analysis of energy programs in Brazil and their contribution to minimize the emission of air pollutants. For this study, a historical survey was conducted, by means of literature review, on the use of energy and governmental energy programs, energy supply, CO2 emissions and scenarios for the year 2030, international agreements and mechanisms for climate change mitigation, sectors of Brazilian society that consume more energy and what are the sources they use, renewable energy technologies available and the climate damage caused by them in energy processes. The systemic epistemological view has based this thesis, since this method was suitable for the managing of the energy issue for the game of harmonization among natural resources, consumption and climate damage, based on the view of an ecossocioeconomia. The main results showed that it is possible to increase the share of less pollutant and renewable energy such as wind, solar, small hydropower plants and biomass in the Brazilian energy matrix and promote energy efficiency in order to increase the supply of energy, reducing the need of using natural energy resources and the consequent environmental impact. It was noted that governmental energy policies and programs contribute to encourage the use of renewable energy and to improve levels of air pollutants. It was concluded that, in order to reduce the emission of greenhouse gases from energy processes while guaranteeing the continuity of economic development, a set of measures is necessary, including: gradual replacement of fossil fuels in energy matrix by renewable sources, in association with energy efficiency, and integrated and viable governmental programs in political, economic, technological and socio-environmental terms. It was observed that there is an interplay of forces involving energy between socio-environmental and economic development and, therefore, at present and near future there is no way to rule out the use of totally non-renewable energy (thermoelectric power plants run by fossil fuels and nuclear energy, and fossil fuels for the transportation sector), considering the need to address the issue of energy safety.
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Wu, Yunhui. "Agent behavior in peer-to-peer shared ride systems /." Connect to thesis, 2007. http://eprints.unimelb.edu.au/archive/00003214.
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Bisoto, Tatiana. "Preparação e caracterização de membranas cerâmicas compostas tubulares para aplicação na separação de gases." reponame:Repositório Institucional da UCS, 2014. https://repositorio.ucs.br/handle/11338/899.
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Este trabalho tem como objetivo preparar membranas compostas de α-alumina recobertas com paládio usando a técnica de deposição química electroless plating associada ao método sol-gel. Foram realizados tratamentos térmicos a 1450°C nos suportes cerâmicos em 6, 12, 18, 24 e 30 h visando verificar a influência do tempo na porosidade do mesmo. Foram preparadas membranas compostas, alumina-Pd com uma, duas e três camadas de paládio na superfície externa do suporte cerâmico, em que o suporte e as membranas foram caracterizados por: análise morfológica realizada por Microscopia Eletrônica de Varredura (MEV) e Microscopia Eletrônica de Varredura de Emissão de Campo (FESEM), porosidade avaliada pelo Método de Brunauer, Emmet e Teller (BET), Método de Barret-Joyner-Halenda (BJH) e porosimetria de mercúrio, quantificação de paládio em solução por Espectrometria de Massa com plasma indutivamente acoplado (ICP-MS) e a permeabilidade e seletividade dos gases mensurada a partir de um equipamento em escala de bancada. O aumento do tempo durante a sinterização não promoveu mudanças significativas na porosidade do suporte, mostrando que o tempo de 6 h de tratamento térmico é suficiente para atingir a menor distribuição de tamanho de poro do material. A formação da camada de paládio foi realizada sem e com a associação do método sol-gel, apresentando uma camada mais homogênea com o uso do método, no entanto a análise de ICP-MS indicou maior quantidade de metal paládio na deposição electroless plating. A análise morfológica indicou espaços vazios menores de acordo com o número de camadas formadas. O suporte cerâmico sem e com camada de paládio apresenta variação na permeabilidade aos gases N2, CH4 e CO2 nas pressões de 100 a 400 kPa e quanto mais espessa a camada de paládio formada, menor é a permeabilidade dos gases.Submitted by Ana Guimarães Pereira (agpereir@ucs.br) on 2015-02-23T18:54:16Z No. of bitstreams: 1 Dissertacao Tatiana Bisoto.pdf: 546380 bytes, checksum: b684b58eaa3e2af8b355719394be7208 (MD5)
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Within this context, this work aims to prepare membranes composed of α-alumina coated with palladium using the electroless plating technique associated with the sol-gel method. To achieve the objectives of the paper, analyzes of porosity of the ceramic support with and without heat treatment of 1450°C for 6; 12; 18; 24 and 30 h, the formation of one, two and three layers of palladium on the external surface of the ceramic support, the effect of the sol-gel method, the chemical and physical properties, permeability and selectivity of the gases were performed. Morphological analysis were performed by Scanning Electron Microscopy (SEM) and Field Emission Scanning Electron Microscope (FESEM), the membrane porosity was evaluated by the Brunauer, Emmet and Teller (BET) theory, Barret-Joyner-Halenda (BJH) method and by mercury porosimetry, the palladium quantification in solution was given by mass spectrometry with inductively coupled plasma (ICP-MS) analysis and gas permeability and selectivity were measured by a bench scale equipment. The time increase during the sinterization did not promote representing changes in the support porosity, which shows that the 6 h time of heat treatment is sufficient to achieve the lowest porosity of the material. The palladium layer formation was realized without and with the combination of the sol-gel method, presenting a more homogeneous layer with the use of the method. However, the ICP-MS analysis indicated a greater amount of palladium deposition without sol-gel method. The morphological analysis showed smaller empty spaces according to the number of layers formed. The ceramic support without and with palladium layer showed variation in permeability to N2, CH4 and CO2 gases at pressures of 100 to 400 kPa and the higher the palladium layer formed, the smaller the gas permeability
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Cunha, Kamyla Borges da. "Papel do Brasil, da Índia e da China Para a efetividade do regime climático pós-2012." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/263831.
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Orientadores: Arnaldo Cesar Walter, Fernando Cardozo Fernandes ReiTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica
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Resumo: A presente tese teve como objetivo principal analisar o papel de Brasil, Índia e China para a efetividade do regime climático pós-2012. Para tanto, foi preciso avaliar a efetividade do regime climático atual, perscrutar sobre os desafios da efetividade do futuro regime climático, identificar as principais semelhanças e diferenças entre o Brasil, a China e a Índia, em termos de contribuição para o efeito estufa adicional, analisar a posição oficial de cada um dos três países e perscrutar o papel desejável do Brasil no regime pós 2012. De modo a cumprir o objetivo proposto, realizou-se uma breve explanação sobre os aspectos científicos das mudanças climáticas, dando-se destaque para os desafios colocados a decisão política; fez-se uma analise do regime climático vigente, de modo a se identificar os principais aspectos foco da discussão sobre o futuro regime; procedeu-se a uma analise dos principais pontos de discussão sobre o regime climático pós-2012, com destaque para a efetividade ambiental do regime, a eficiência econômica e a equidade. Tais aspectos foram então avaliados sob a perspectiva política, de modo a destacar sua inserção na evolução das negociações internacionais. Buscou-se focar nos três países avaliados, levantando-se-lhes o perfil de emissões, energia e uso da terra, dados demográficos, econômicos e sociais, assim como sua postura política nas negociações internacionais. Realizadas todas essas analises, identificou-se a importância do Brasil, da China e da Índia para a efetividade do regime climático pós-2012, seja em função de sua crescente contribuição para as emissões de gases de efeito estufa, seja por forca de seu papel econômico, tanto no que diz respeito a distribuição dos custos de mitigação quanto ao cenário atual de crescente interdependência econômica. Também se constatou a ausência de correlação direta entre as emissões brasileiras de gases de efeito estufa e o desenvolvimento socioeconômico do pais, já que a maior parte decorre de desmatamentos ilegais. Entendeu-se que a postura brasileira há de focar-se nas oportunidades da assunção de compromissos voluntários relativos a redução das taxas de desmatamento
Abstract: This study aims at analyzing the role of Brazil, India and China for the of the international post-2012 climate change regime effectiveness. In order to meet this goal, it was necessary to evaluate the present climate regime effectiveness, to identify the main similarities and differences between Brazil, India and China, in terms of their contribution to greenhouse effect, to analyze their official position in the international negotiations and to evaluate the desirable role of Brazil in the post-2012 climate regime. The scientific aspects of climate change were briefly explored, in order to highlight the main challenges faced by the political decision. The present climate change regime was analyzed, in order to pose the main aspects of climate change discussion. The post-2012 climate regime effectiveness was posed in terms of wide participation of main countries and the need to bring together two main points: economic efficiency and equity. Then, the climate change international negotiation evolution was presented. After this general approach, this study has focused Brazil, India and China national circumstances, such as their greenhouse gases emissions profile, energy and land use sectors, demographic, economic and social indicators, as well their political position in the climate change international negotiations. As a result of such analysis, it was possible to identify the importance of Brazil, India and China for the post-2012 climate change regime effectiveness, first, because of their major contribution to greenhouse gases emissions, and second, because of their economic role, both in terms of mitigation costs distribution and in terms of the international economic interdependence. It was also identified the absence of direct relationship between Brazilian emissions and the country's socioeconomic development, considering that most of Brazil's emission come from illegal deforestation. It was concluded that Brazil could benefit in a scenario of position flexibility, assuming voluntary commitments related to deforestation reduction
Doutorado
Planejamento de Sistemas Energeticos
Doutor em Engenharia Mecânica
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Anselmo, Christophe. "Atmospheric greenhouse gases detection by optical similitude absorption spectroscopy." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSE1131/document.
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Cette thèse porte sur le développement théorique et expérimental d’une nouvelle méthodologie de détection des gaz à effet de serre basée sur la spectroscopie optique d’absorption. La question posée était : est-il possible d’évaluer de manière univoque la concentration d’un gaz à partir d’une mesure par spectroscopie d’absorption différentielle, dans laquelle l’étendue spectrale de la source lumineuse est plus large que celle d’une ou de plusieurs raies d'absorption de la molécule considérée et que, de plus la détection n’est pas résolue spectralement ? La réponse à cette question permettra d’entrevoir à terme le développer d’un instrument de télédétection de terrain robuste sans contrainte opto-mécanique majeure aussi bien sur la source laser que sur la chaîne de détection.Ces travaux ont donné lieu au développement d’une nouvelle méthodologie que l’on dénomme « Optical Similitude Absorption Spectroscopy » (OSAS) ou spectroscopie d’absorption optique de similitude. Cette méthodologie permet donc de déterminer de manière quantitative une concentration d’un gaz à partir de mesures d’absorption différentielle non résolue spectralement sans procédure de calibration en concentration. Ceci demande alors une connaissance précise de la densité spectrale de la source lumineuse et du système de détection. Ces travaux publiés ont permis de démontrer que cette nouvelle méthodologie est dans le domaine spectral du proche infrarouge peu sensible aux conditions thermodynamiques du gaz observé. D’autre part, ces travaux ont permis de mettre en exergue l’inversion de la Loi de Beer-Lambert non résolue spectralement ce qui donne lieu à la résolution d’un système analytique non linéaire. À cette fin le développement d’un nouvel algorithme d’inversion de ce type de mesures a pu être vérifié expérimentalement en laboratoire sur le méthane, en exploitant aussi bien des sources à large bande spectrale cohérente et non cohérente. La détection de cette molécule dans l’atmosphère a pu être réalisée dans le cadre de ces travaux en couplant judicieusement la méthodologie OSAS et la technique Lidar. Ces travaux ouvrent de nombreuses perspectives sur la détection de gaz à effet de serre dans le domaine spectral infrarouge ainsi que la possibilité de détecter plusieurs molécules d’intérêt atmosphérique simultanémentThis thesis concerns the theoretical and experimental development of a new methodology for greenhouse gases detection based on the optical absorption. The problem relies on the unambiguous retrieval of a gas concentration from differential absorption measurements, in which the spectral width of the light source is wider than one or several absorption lines of the considered target gas given that the detection is not spectrally resolved. This problem could lead to the development of a robust remote sensing instrument dedicated to greenhouse gas observation, without strong technology limitations on the laser source as well as on the detection system. Solving this problem, we could propose a new methodology named: "Optical Similitude Absorption Spectroscopy" (OSAS).This methodology thus allows to determine a quantitative target gas concentration from non-resolved differential absorption measurements avoiding the use of a gas concentration calibration procedure. Thereby, a precise knowledge of the emitted power spectral density of the light source and the efficiency of the detection system are needed.This work that has been recently published could demonstrate that this new methodology applied on the NIR remains accurate even in the presence of strong atmospheric pressure and temperature gradients. Moreover, we show that inverting spectrally integrated measurements which follow the Beer-Lambert law leads to solve a nonlinear system. For this, a new inversion algorithm has been developed. It was experimentally verified in laboratory on methane by using coherent and non-coherent broadband light sources. The detection of methane in the atmosphere could be also realized by coupling the OSAS methodology and the Lidar technique. Outlooks are proposed and especially on the detection of greenhouse gases in the infrared spectral domain as well as the ability to simultaneously detect several atmospheric molecules of interest
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Barbi, Fabiana 1980. "Governando as mudanças climáticas no nível local : riscos e respostas políticas." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/281181.
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Orientadores: Leila da Costa Ferreira, Carlos Alfredo JolyTese (doutorado) - Universidade Estadual de Campinas, Instituto de Filosofia e Ciências Humanas
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Resumo: O objetivo dessa tese é analisar como os tomadores de decisão têm se apropriado dos riscos das mudanças climáticas em suas políticas locais e na integração com as políticas existentes, em diferentes níveis de governança. Para analisar o processo de internalização dos riscos das mudanças climáticas em termos de respostas políticas ao problema pelos governos locais e metropolitano, construiu-se uma matriz analítica baseada em quatro pontos: riscos das mudanças climáticas na região; estruturas político-institucionais para a questão climática; respostas políticas relacionadas às mudanças climáticas e percepções dos atores governamentais acerca do tema. Essa matriz analítica foi concebida a partir dos capítulos teóricos e utilizada no estudo em profundidade na cidade de Santos, na Região Metropolitana da Baixada Santista. Os resultados mostraram que essa região é bastante vulnerável aos riscos das mudanças climáticas e mostraram a existência de algumas ações governamentais relacionadas a essa questão em diferentes setores de atuação no nível local e metropolitano. Entretanto, nenhuma dessas ações está diretamente voltada a lidar com os riscos das mudanças climáticas, abordando essa questão de maneira tangencial. Os riscos das mudanças climáticas não estão sendo internalizados pelos governos em termos de respostas políticas, embora ações referentes a esses riscos sejam misturadas às respostas governamentais a outros problemas urbanos que possuem interface com a questão climática e podem ser exacerbados a partir das mudanças no clima. Na região estudada, os riscos das mudanças climáticas são internalizados como riscos naturais, isto é, as respostas políticas estão mais direcionadas aos riscos naturais do que aos riscos climáticos, não incorporando os cenários previstos de mudanças climáticas nas respostas governamentais. Os riscos das mudanças climáticas são produtos dos próprios processos de desenvolvimento das sociedades contemporâneas. Isso implica no questionamento desses processos. E isso, as políticas climáticas ou relacionadas às mudanças climáticas apresentadas nessa tese estão longe de lograr, ou seja, elas não vão ao cerne do problema, mas se configuram como paliativos que permitem manter os mesmos padrões de desenvolvimento conhecidos até aqui: poluidores e emissores de gases de efeito estufa
Abstract: The aim of this dissertation is to analyze how policy makers have internalized the risks of climate change in their local policies and have integrated them with existing policies at different levels of governance. In order to analyze the internalization process of climate change risks in terms of policy responses to the problem by local and metropolitan governments, an analytical matrix based on four points was constructed: the risks of climate change; political-institutional structures for the climate issue; climate-relate policy responses and the perceptions of governmental actors on the subject. This analytical matrix was based on the theoretical chapters and used in the in-depth study in the city of Santos, in the Santos Metropolitan Region. The results showed that this region is quite vulnerable to the risks of climate change and showed the existence of some government actions related to this issue in different sectors of activity, at the local and metropolitan levels. However, none of these actions is directly geared to deal with climate change risks, addressing them tangentially. The risks of climate change are not being internalized by governments in terms of policy responses, although actions related to these risks are mixed to other policy responses to urban problems that have interface with the climate issue and may be exacerbated by changes in the climate. In the study area, the risks of climate change are internalized as natural hazards, i.e., the political responses are more directed to natural hazards than to climate risks, without incorporating climate change scenarios into the political responses. Climate change risks are products of the development processes themselves in contemporary societies. This implies questioning these processes. The climate or climate-related policies presented in this thesis are far from achieving this, i.e., they do not go to the heart of the problem, but are configured as palliatives that allow the maintenance of the same development standards known so far: polluters and greenhouse gases emitters
Doutorado
Aspectos Sociais de Sustentabilidade e Conservação
Doutora em Ambiente e Sociedade
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Sousa, Jocy Ana Paixão de. "Mudanças de uso da terra e estimativas de emissões antrópicas de CO2 em bacia hidrográfica." Universidade Estadual Paulista (UNESP), 2018. http://hdl.handle.net/11449/152685.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
As interferências antrópicas sobre natureza sempre provocaram impactos ambientais. Porém, entre os mais significativos encontram-se as mudanças de uso da terra, nos quais contribuem com as emissões dos gases do efeito estufa. Entre esses principais gases destacam-se o dióxido de carbono, CO2. O estudo apresentou como objetivo estimar as emissões do dióxido de carbono devido as mudanças de uso da terra para a análise do fluxo de carbono em bacia hidrográfica. A área de estudo localiza-se na Bacia Hidrográfica do Rio Una, Ibiúna, São Paulo. Para atingir os objetivos foram realizados o mapeamento de uso do solo e cobertura vegetal, mapeamento pedológico, análise da textura do solo, mapeamento da vegetação pretérita, estoque de carbono sob associação solo-vegetação, matriz de transição e os cálculos das emissões líquidas de CO2. Constatou-se que em relação ao mapeamento do uso do solo e cobertura vegetal, o maior quantitativo foi de floresta e estas predominam no sul da bacia. Ao longo de nove anos houve uma redução de florestas, campo e área alagada e um aumento da área de agricultura, área urbana, pastagem e reflorestamento. Foram encontrados solos do tipo Argissolos e Latossolos, além das texturas argilosa, franco-argilo-arenosa, argilo-arenosa e franco-argilosa. Para a vegetação pretérita constatou-se floresta ombrófila densa montana, floresta estacional decidual e semidecidual. Em relação ao conteúdo de carbono no solo sob a associação solo-vegetação foram definidos valores que variam de 2,59 a 6,33 Kgc/m2. Nas matrizes de transições para os períodos de 2007-2010, 2010-2013 e 2013-2016, observou-se que a floresta convertida para as demais categorias apresentou posição de destaque. As emissões líquidas para todos os períodos mostraram que há mais emissões do que remoções na bacia, com um destaque para o período de 2013 a 2016, em que houve uma maior estimativa de emissões CO2, porém a menor remoção ocorreu no último período. A pesquisa mostrou que a maioria das transições que ocorreram foram em função da mudança de floresta para outras categorias, fator que mais contribuiu para emissões líquidas de CO2, resultante do intenso processo de antropização da bacia.
Anthropogenic interference with nature has always had environmental impacts. However, among the most significant are land use changes, in which they contribute to the emissions of effect gases, especially carbon dioxide, CO2. The objective of the study was to estimate carbon dioxide emissions due to the change in land use for an analysis of the carbon flux in the watershed. The study area is located in the Una Watershed, Ibiúna, São Paulo. To achieve the objectives, the mapping of land use and vegetation cover, pedological mapping, soil texture analysis, mapping of past vegetation, carbon stock under soil-vegetation association, transition matrix, and calculations of net CO2 emissions. It was verified that in relation to the mapping of the land use and vegetal cover, the biggest quantitative one was of forest and these predominate in the south of the basin. During nine years there was a reduction of forests, field and flooded area and an increase of the area of agriculture, urban área, pasture and reforestation. Soils of the type Argisols and Latosols were found, in addition to clay, clay-loam-sandy, clay-sandy and loam-loamy textures. For the past vegetation it was verified dense montane forest, deciduous and semidecidual forest. Regarding the non-singlet carbon content in a soil-vegetation association to define values ranging from 2.59 to 6.33 Kgc / m2. In the transitional matrices for the periods 2007-2010, 2010-2013 and 2013-2016, it was observed that the forest converted to the other categories presented a prominent position. Net emissions for all periods showed that there are more emissions than removals in the basin, with a highlight for the period from 2013 to 2016, where there was a higher estimate of CO2 emissions, but the lowest removal occurred in the last period. The research showed that most of the transitions that occurred were due to the change of forest to other categories, which contributed most to net CO2 emissions, resulting from the intense process of anthropization of the basin.
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Rocha, Marcelo Theoto. "Aquecimento global e o mercado de carbono: uma aplicação do modelo CERT." Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/11/11132/tde-13052003-163913/.
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As ações decorrentes das atividades econômicas e industriais têm provocado alterações na biosfera, resultando na quase duplicação da concentração de Gases de Efeito Estufa (GEE) na atmosfera durante o período de 1750 a 1998. A alteração da concentração dos GEE poderá desencadear um aumento da temperatura média no planeta entre 1,4 e 5,8°C nos próximos cem anos (IPCC, 2001a). Para tratar do problema do efeito estufa e suas possíveis conseqüências sobre a humanidade foi estabelecida em 1992, durante a Rio 92, a Convenção Quadro das Nações Unidas sobre Mudanças Climáticas. A Conferência das Partes realizada em Quioto em 1997 destaca-se como uma das mais importantes, uma vez que durante sua realização foi estabelecido um acordo onde se encontram definidas metas de redução da emissão de GEE para os países do ANEXO B (países do ANEXO I com compromissos de redução das emissões de GEE), além de critérios e diretrizes para a utilização dos mecanismos de mercado. Este acordo ficou conhecido como Protocolo de Quioto e estabelece que os países industrializados devem reduzir suas emissões em 5,2% abaixo dos níveis observados em 1990 entre 2008-2012 (primeiro período de compromisso). O Protocolo criou o Mecanismo de Desenvolvimento Limpo (MDL). A idéia do MDL consiste em que cada tonelada de CO2 deixada de ser emitida, ou retirada da atmosfera por um país em desenvolvimento, poderá ser negociada no mercado mundial através de Certificados de Emissões Reduzidas (CER). Esta tese teve como objetivo geral caracterizar o "mercado de carbono", em especial a participação do Brasil através do MDL. Para tanto foi feita uma análise de como este mercado está sendo formado e como deverá ser sua evolução até a possível formação de mercados futuros. Os objetivos específicos foram: 1) Determinar o tamanho do mercado global e a participação do Brasil (através do MDL) em diversos cenários; e, 2) Analisar se os CER gerados em projetos de MDL, em especial por projetos de seqüestro de carbono, poderiam se tornar uma "commodity ambiental" ou não. Ficou claro que o mercado de carbono já é uma realidade, porém encontra-se em um estágio inicial de sua formação. Para estimar o tamanho do mercado utilizou-se o Modelo CERT (Carbon Emission Reduction Trade). Nos cenários de referência do Modelo a maior participação brasileira no mercado de CER foi de apenas 3,4% (Cenário 7), através da venda de 14,4 milhões de toneladas de carbono, gerando um receita de US$ 237 milhões ao custo de US$ 106,3 milhões. O lucro de todos os projetos de MDL no Brasil foi de US$ 130,7 milhões. Nos cenários alternativos a maior participação foi de 17,8% (Cenário Alternativo 7), através da venda de 32,1 milhões de toneladas de carbono, gerando um receita de US$ 525,6 milhões ao custo de US$ 198 milhões. O lucro de todos os projetos de MDL no Brasil neste caso foi de US$ 327,6 milhões.The economic and industrial anthropogenic activities are increasing the Green House Gas (GHG) atmospheric concentration. These gases can increase the atmosphere temperature in 1.4 to 5.8°C in the next hundred years (IPCC, 2001a). To solve this problem was created in 1992 the United Nations Framework Convention on Climate Change. The Conference of the Parties held at Kyoto in 1997 was one of the most important, since it created an international agreement about the GHG emission reductions to the ANNEX B countries. This agreement is called the Kyoto Protocol and it determine that the industrialized countries should decrease the GHG emissions in 5,2% below the 1990 levels between 2008-2012 (first period commitment). The Protocol also created the Clean Development Mechanism (CDM). The idea of the CDM is that each tone of CO2 that is reduced or sequestered from the atmosphere by a developing country can be negotiated through Certified Emission Reduction (CER).This thesis had the main objective of understand the "carbon market", in special the Brazilian participation through the CDM. The specific objectives was: 1) Determine the size of the global market and the Brazilian participation (through the CDM) in different scenarios; and, 2) To analyze if the CER created by forest projects can be a environmental commodity. It was clear that the carbon market exists but is in an initial phase. To estimate the size of the market the CERT (Carbon Emission Reduction Trade) Model was used. In the reference scenarios the best Brazilian participation, through the CER, was only 3.4% (Scenario 7), selling 14.4 millions tons of carbon, with a revenue of US$ 237 millions and costs of US$ 106.3 millions. The profits of all CDM projects in Brazil was US$ 130,7 millions. In the alternative scenarios the best Brazilian participation was 17.8% (Alternative Scenario 7), selling 32.1 millions tons of carbon, with a revenue of US$ 525.6 millions and costs of US$ 198 millions. In this case the profits of all CDM projects in Brazil was US$ 327.6 millions.
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Wilson, Craig Michael. "Barriers and drivers to the implementation of the "clean development mechanism" within the Nelson Mandela Bay Municipality: a case study." Thesis, Rhodes University, 2008. http://hdl.handle.net/10962/d1003851.
Full textAbstract:
The global threat of climate change is one of the most crucial environmental issues facing the world in modern times. In response to this threat, international governments have drafted the Kyoto Protocol which included the Clean Development Mechanism (CDM). The CDM is a scheme which invited developing countries, like South Africa, to become involved in climate change mitigation projects. While South Africa has been identified as an attractive host country for CDM projects, research has revealed that it lags behind other developing countries in this regard. This study provides a theoretical background to the CDM and grounds the subject within the field of Environmental Economics. Following a literature review of factors that could influence the involvement of a municipality in CDM projects, this thesis undertook a case study of the barriers and drivers to CDM implementation within the Nelson Mandela Bay Municipality (NMBM). Use was made of semi-structured interviews, where a questionnaire was used to guide the researcher’s interview process. Five NMBM officers, who were likely to have been involved with CDM project implementation, were interviewed. Data collected was analyzed using a coding technique and was compared and contrasted to the literature in a process of explanation building. It was possible to elicit 14 factors that acted as CDM-barriers; seven that acted as CDM-drivers; and 10 that were required to change within the NMBM to encourage greater CDM involvement. Of the barriers, lack of awareness, poor political will and lack of funding emerged as the most inhibiting. Of the CDM-drivers, the potential financial benefits; ownership of infrastructure capable of producing carbon assets; and technology transfer emerged as the factors most likely to promote CDM involvement. With regards the factors that require change, it emerged that a positive response would result from a proactive stance by National Government on the CDM; the use of Public-Private-Partnerships to facilitate CDM projects; and improved communication and capacity building within the NMBM and the Nelson Mandela Bay business community. The main recommendation offered to the NMBM was for it to draft a Sustainable Development Policy as well as a formal sustainable development strategy to drive a coherent and consolidated approach to the Municipality’s involvement with CDM projects. Further, it was proposed that the NMBM should, lobby National Government for it to promulgate enabling legislation and a framework which would encourage CDM investment in South Africa; and engage with local business to promote the active involvement of the Nelson Mandela Bay with the implementation of CDM projects. Keywords: Global Warming, Kyoto Protocol, Clean Development Mechanism, Sustainable Development, Environmental Economics, Public Sector, Nelson Mandela Bay Municipality.
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Ventura, Robert E. "Wetlands and Greenhouse Gas Fluxes: Causes and Effects of Climate Change – A Meta-Analysis." Scholarship @ Claremont, 2014. http://scholarship.claremont.edu/pomona_theses/107.
Full textAbstract:
Climate change is one of the largest problems facing this generation. Anthropogenically caused increases of greenhouse gas emissions is a significant culprit to this problem. Although the obvious problems such as cars, industry, and urbanism garnish a significant amount of the criticism, natural sources such as wetlands are also beginning to contribute to this issue. This is becoming increasingly significant as wetlands shift from being sinks of greenhouse gases to becoming sources as various anthropogenic impacts, including global warming itself, begin to affect the health of the wetlands. The aim of this project is to look at four common types of wetlands, being tropical mangroves, temperate coastal marshes, inland meadows, and subarctic peatlands, all located in different climactic areas of the world, and by doing a meta-analysis of available data of greenhouse gas production for each wetland type, observe how differences in their greenhouse gas production may contribute or be affected by climate change and global warming. Results of the meta-analysis revealed that the most significant production of the potent greenhouse gas nitrous oxide occurs in coastal wetlands such as tropical mangroves and coastal marshes, while the greenhouse gas methane is seen to be produced most in subarctic peatlands. These contributions of wetlands to global greenhouse gas production are not as significant as other anthropogenic contributions. However, subarctic wetlands contribute to more than half of the global methane emissions, and the most important aspect of wetland greenhouse gas production is that they are producing more greenhouse gases than they would normally be sequestering, contributing more than the basic greenhouse gas production data can display. Global climate changes such as temperature increase and sea level rise could also make these levels of greenhouse gas production become worse, although measures to decrease the effects of this such as regulations on anthropogenic nitrogen input, macrophyte presence, and prevention of peat burning.
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Quaas, Johannes, Jean-Louis Dufresne, Olivier Boucher, and Treut Hervé Le. "Impacts of greenhouse gases and aerosol direct and indirect effects on clouds and radiation in atmospheric GCM simulations of the 1930-1989 period." Universitätsbibliothek Leipzig, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-189692.
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Among anthropogenic perturbations of the Earth\'s atmosphere, greenhouse gases and aerosols are considered to have a major impact on the energy budget through their impact on radiative fluxes. We use three ensembles of simulations with the LMDZ general circulation model to investigate the radiative impacts of five species of greenhouse gases (CO2, CH4, N2O, CFC-11 and CFC-12) and sulfate aerosols for the period 1930-1989. Since our focus is on the atmospheric changes in clouds and radiation from greenhouse gases and aerosols, we prescribed sea surface temperatures in these simulations. Besides the direct impact on radiation through the greenhouse effect and scattering of sunlight by aerosols, strong radiative impacts of both perturbations through changes
in cloudiness are analysed. The increase in greenhouse gas concentration leads to a reduction of clouds at all atmospheric levels, thus decreasing the total greenhouse effect in the longwave spectrum and increasing absorption of solar radiation by reduction of cloud albedo. Increasing
anthropogenic aerosol burden results in a decrease in high-level cloud cover through a cooling of the atmosphere, and an increase in the low-level cloud cover through the second aerosol indirect effect. The trend in low-level cloud lifetime due to aerosols is quantified to 0.5 min day-1 decade-1 for the simulation period. The different changes in high (decrease) and low-level (increase) cloudiness due to the response of cloud processes to aerosols impact shortwave radiation in a contrariwise manner, and the net effect is slightly positive. The total aerosol effect including also the aerosol direct and first indirect effects remains strongly negative.
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Quaas, Johannes, Jean-Louis Dufresne, Olivier Boucher, and Treut Hervé Le. "Impacts of greenhouse gases and aerosol direct and indirect effects on clouds and radiation in atmospheric GCM simulations of the 1930-1989 period." Laboratoire de Météorologie Dynamique, 2004. https://ul.qucosa.de/id/qucosa%3A13985.
Full textAbstract:
Among anthropogenic perturbations of the Earth\''s atmosphere, greenhouse gases and aerosols are considered to have a major impact on the energy budget through their impact on radiative fluxes. We use three ensembles of simulations with the LMDZ general circulation model to investigate the radiative impacts of five species of greenhouse gases (CO2, CH4, N2O, CFC-11 and CFC-12) and sulfate aerosols for the period 1930-1989. Since our focus is on the atmospheric changes in clouds and radiation from greenhouse gases and aerosols, we prescribed sea surface temperatures in these simulations. Besides the direct impact on radiation through the greenhouse effect and scattering of sunlight by aerosols, strong radiative impacts of both perturbations through changes
in cloudiness are analysed. The increase in greenhouse gas concentration leads to a reduction of clouds at all atmospheric levels, thus decreasing the total greenhouse effect in the longwave spectrum and increasing absorption of solar radiation by reduction of cloud albedo. Increasing
anthropogenic aerosol burden results in a decrease in high-level cloud cover through a cooling of the atmosphere, and an increase in the low-level cloud cover through the second aerosol indirect effect. The trend in low-level cloud lifetime due to aerosols is quantified to 0.5 min day-1 decade-1 for the simulation period. The different changes in high (decrease) and low-level (increase) cloudiness due to the response of cloud processes to aerosols impact shortwave radiation in a contrariwise manner, and the net effect is slightly positive. The total aerosol effect including also the aerosol direct and first indirect effects remains strongly negative.
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Dohnal, Jan. "Měření koncentrací skleníkových plynů." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2017. http://www.nusl.cz/ntk/nusl-242039.
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This semester thesis deals with the greenhouse effect, various gases and methods of measurement. On the greenhouse effect is viewed from its historical dating, despite changes in atmospheric composition and reactions of individual institutions. It contains a theoretical analysis of the individual gases. It focuses on the most harmful greenhouse gases such as water vapor, carbon dioxide, nitrous oxide, methane, ozone, chlorofluorocarbons and halons. Analysis methods for detection of gaseous substances. Part of this work is focus on the detection of nitrogen dioxide and chloro-fluorocarbon. The data is processed using a microcontroller and then sent to an Internet server thingspeak.com. If the device proves successful, will be used as a laboratory exercise in the course Ecology in electronics.
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Silva, Cleyton Martins da. "Avaliação de gases efeito estufa na cidade do Rio de Janeiro." Universidade do Estado do Rio de Janeiro, 2012. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=3533.
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O presente trabalho teve como objetivo a validação de uma metodologia de amostragem para GEE Gases do Efeito Estufa, com a utilização de seringas e análise por cromatografia de fase gasosa com múltiplos detectores. O trabalho se dividiu em duas etapas. A primeira etapa consistiu em um teste de estabilidade avaliando o meio de amostragem proposto, a seringa, e comparando-o a dois meios de amostragem convencionais canister e bolsa de teflon -, utilizando uma amostra padrão de GEE. A segunda etapa foi a aplicação desta nova metodologia de amostragem na cidade do Rio de Janeiro, buscando a avaliação da concentração dos GEE em diferentes bairros da cidade e a correlação destas com dados meteorológicos e características da localização dos pontos amostrados. Nestas amostragens realizadas na cidade do Rio de Janeiro obteve-se uma média de 536 ppmv, 2,04 ppmv e 274 ppbv, para o CO2, CH4 e N2O, respectivamente, que foram os GEE analisados. Foi possível neste trabalho verificar o grau de correlação dos GEE estudados com variáveis meteorológicas, bem como com outros poluentes já legislados e participantes de monitoramento contínuo. As conclusões alcançadas foram que a nova metodologia proposta para amostragem de GEE é viável devido ao seu bom desempenho no teste de estabilidade, ao baixo custo do material empregado e à praticidade do mesmo, e que as concentrações dos GEE avaliados na cidade do Rio de Janeiro encontram-se superiores às concentrações indicadas como médias globais para os mesmos. Apontando desta forma, a necessidade de um monitoramento contínuo destes de forma a contribuir para a tomada de ações de mitigação dos GEEThe purpose of this study is to validate a sampling methodology for GHG Greenhouse Gases, with the use of syringes and analyzed by gas chromatography with multiple detectors. The work was divided into two steps. The first one consisted of a stability test evaluating the proposed use of sampling, the syringe, and comparing it to two conventional sampling media - canister and teflons bag - using a standard sample of GHG. The second step was the application of this new sampling methodology in the city of Rio de Janeiro, seeking the GHG concentrations assessment in different districts of the city and the correlation of these data and meteorological characteristics of the location of sampling sites. In these samples collected in the city of Rio de Janeiro resulted in an average of 536 ppmv, 2.04 ppmv and 274 ppbv, for CO2, CH4 and N2O, respectively, which were the GHG analyzed. It was possible, in this paper, to verify the degree of correlation into the studied GHG and the meteorological variables, as well into others pollutants that are already legislated and participates of a continuous monitoring plan. The conclusions reached were that the proposed new methodology for GHG sampling is viable due to its good performance in stability, low cost of the material used and the practicality of it, and that the concentrations of greenhouse gases measured in the city of Rio de Janeiro are higher than the global average concentrations of them. Pointing, this way, the need for continuous monitoring of these, that should contribute to the actions of GHG mitigation
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David, Gregory. "Polarization-resolved backscattering from nanoparticles in the atmosphere : field and laboratory experiments." Thesis, Lyon 1, 2013. http://www.theses.fr/2013LYO10225/document.
Full textAbstract:
Cette thèse porte sur l’étude des gaz et nanoparticules diélectriques de l’atmosphère, fortement incriminés pour leur rôle sur le bilan radiatif terrestre et le changement climatique.Ces travaux de recherche, réalisées au sein de l’Institut Lumière Matière, traitent plus spécifiquement de la rétrodiffusion de la lumière, résolue en polarisation, par les nanoparticules de l’atmosphère, afin d’étudier la complexité des processus atmosphériques qui la composent, tels que la nucléation. En complément à cette approche particulaire, les gazà effet de serre sont également étudiés, en suivant une méthode originale, consistant à évaluer leur concentration atmosphérique, par couplage d’un télédétecteur lidar possédant une large bande spectrale avec la spectroscopie optique de corrélation (Thomas et al., 2012, 2013a,b). Une attention particulière a été portée à la réalisation de mesures sensibles et précises utilisant un lidar multi-spectral (UV, VIS), résolu en polarisation (David et al., 2012). Comme premier résultat, un coefficient de rétrodiffusion aussi faible que (2,4 ± 0,5) × 10−8 m−1.sr−1, a été mesuré dans l’UV en polarisation croisée à celle du laser incident dans la troposphère libre, avec une limite de détection de la dépolarisation de δp = 0,6 % (proche de la dépolarisation moléculaire), observée à plus de 4 kilomètres d’altitude. Ensuite, une méthode nouvelle a été développée pour retrouver, dans un mélange externe de particules à deux/trois composantes chimiques, le coefficient de rétrodiffusion de chacune de ces composantes. Pour ce faire, le coefficient d’Angström et la dépolarisation de chaque espèce chimique doivent être déterminés précisément. On montre dans ce travail de thèse que ces coefficients peuvent être déterminés soit par simulation numérique de la diffusion simple (algorithme T-matrix), soit directement par des mesures de laboratoire. Les hypothèses et les performances de cette méthode sont ensuite discutées dans trois cas d’étude : i) mélange externe de particules desulfates avec les cendres volcaniques issues de l’éruption de 2010 du volcan Eyjafjallajökull (Miffre et al., 2011, 2012a, b) ii) mélange externe de poussières désertiques dans la troposphère libre (Miffre et al., 2011 ; Dupart et al., 2012) observé lors d’un épisode detempête de sable désertique à Lyon (juillet 2010), iii) mélange externe à trois composantes : poussières désertiques, sels de mer et particules solubles dans l’eau (David et al., 2013a). Ces mesures atmosphériques ont conduit à plusieurs résultats: (a) détermination à distance de la concentration en nombre en particules volcaniques (cas i), désertiques (cas ii) (Miffre et al.,2011). Par construction, ces mesures de concentration sont spécifiques à ces particules et intègrent les effets de taille et de sédimentation (Miffre et al., 2012b) ; (b) Evolution de la rétrodiffusion en fonction de l’hygroscopicité de ces particules ; (c) Observation de la formation de nouvelles particules dans l’atmosphère (nucléation) à partir des mesures lidar UV, résolues en polarisation. Ce résultat nouveau ouvre de nouvelles perspectives à la pointede la recherche actuellement réalisée en physico-chimie de l’atmosphère (Dupart et al., 2012). En conclusion, cette thèse explore la diffusion optique d’un ensemble de nanoparticules et l’extinction d’une nanoparticule diélectrique unique, en les mesurant de manière très sensible et précise, en atmosphère réelle comme en laboratoire, tout en étayant cette approche expérimentale par des simulations numériques. Cette approche ouvre des perspectives nouvelles, portant sur les propriétés microphysiques de ces nanoparticules atmosphériques(Dupart et al., 2012, David et al., 2013b)Atmospheric greenhouse gases and nanometer-sized particles are incriminated for their role on the Earth radiative budget and climate. This thesis relates the research performed on thepolarization-resolved backscattering of these nano-sized particles and demonstrates itsusefulness to address complex atmospheric processes like particles nucleation. Greenhouse gases are also studied, by coupling a spectrally broadband lidar with optical correlation spectroscopy to remotely evaluate their atmospheric content (Thomas et al., 2012, 2013a,b). Special care has been taken to perform sensitive and accurate UV-VIS polarization lidar measurements (David et al., 2012). Hence, and as a first result, cross-polarized backscattering coefficients as low as (2.4 ± 0.5)×10−8 m−1.sr−1 have been measured in the troposphere, corresponding to UV-particles depolarization detection limit of 0.6 % at 4 km altitude, close to the molecular depolarization. Then, a new methodology has been developed to retrieve, in atwo/three component particle external mixture, the backscattering coefficients specific to eachparticle component (David et al., 2013a). For that purpose, accurate knowledge on the backscattering Ångstrom exponent and depolarization ratio of each particle type must beaddressed. This task is here achieved by performing either single-scattering numerical simulations using T-matrix, or alternatively by performing laboratory measurements. Thei nherent assumptions and the performance of the methodology are then discussed for three case studies of external mixing: i) spherical sulfate mixed with volcanic ash released from the Eyjafjallajökull 2010 eruption (Miffre et al., 2011, 2012a, b), ii) desert dust mixed with nondustparticles (Miffre et al., 2011 ; Dupart et al., 2012), iii) desert dust mixed with sea-salt andbackground spherical particles as an example of a three-component particle mixture (David etal., 2013a). From these field measurements, three main results have been retrieved: (a) Rangere solved particles number concentrations specific to one particle component (ash, dust)(Miffre et al., 2011, 2012b), which include the variability in the particle size distribution, the particles refractive index and possible sedimentation effects(Miffre et al., 2012b), (b) particle backscattering enhancement due to hygroscopic growth, (c) observation of new particle formation in the atmosphere using a sensitive UV polarization lidar, which is new and opens new insights at the forefront of knowledge in atmospheric physics and chemistry (Dupart etal., 2012). As a conclusion, this thesis explores the optical scattering properties of a single / an ensemble of nanoparticles, addressing them in the real atmosphere, through sensitive and accurate lidarand laboratory experiments and numerical simulations, showing new outlooks on the microphysical properties of these atmospheric nanoparticles (Dupart et al., 2012, David et al.,2013b)
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Thomas, Benjamin. "Télédétection de gaz traces atmosphériques par spectroscopie optique de corrélation et lidar." Thesis, Lyon 1, 2013. http://www.theses.fr/2013LYO10180/document.
Full textAbstract:
Ce travail présente une nouvelle méthode de télédétection à distance de la concentration d’un gaz trace dans l’atmosphère basée sur le couplage de la méthode spectroscopique de corrélation optique (Optical Correlation Spectroscopy, OCS) et la technologie de télédétection lidar dans lequel une source laser de large étendue spectrale est considérée. Les premiers travaux furent consacrés au développement d’un nouveau formalisme pour estimer la concentration d’un gaz trace dans l’atmosphère à partir des signaux OCS-lidar. Pour évaluer les performances d’une telle méthode, un modèle numérique simulant des signaux OCS-lidar pour la mesure de la concentration de méthane et de vapeur d’eau a été réalisé. L’influence de la pression et la température sur les propriétés spectroscopiques de ces gaz sur les mesures de concentration a également été étudiée. En plus de ce travail théorique, la première démonstration expérimentale de l’OCS-lidar est présentée en utilisant un lidar basé sur une source laser femtoseconde. Les mesures OCS-lidar ont été réalisées au moyen d’un nouveau système expérimental entièrement élaboré et construit pendant cette thèse. Pour réaliser les mesures consacrées à la teneur en vapeur d’eau de l’atmosphère, la bande d’absorption de la molécule de H2O 4ν à 720 nm a été utilisée. Ainsi les résultats obtenus ont montré le potentiel de la méthode OCS5 lidar pour mesurer la concentration de vapeur d’eau. Par la suite, le développement de la méthodologie OCS-lidar dédiée à la mesure du méthane est présenté. La bande d’absorption 2ν3 à 1,66 μm est exploitée et les premières mesures des signaux lidar sont exposées. Ce travail se termine par la présentation des possibles perspectives d’évolutionIn this thesis, a new active remote sensing methodology is proposed to evaluate the content of atmospheric trace gases. The new methodology is based on laser spectroscopy and consists in coupling a spectrally broadband lidar with optical correlation spectroscopy (OCS-lidar). As a first step, a new formalism has been developed to remotely evaluate the target gas concentration from the OCS-lidar signals. To evaluate the performance of this new methodology, a numerical model simulating OSC-lidar signals for methane and water vapor measurement has been developed. Moreover, the influence of the absorption spectroscopic line parameters, such as atmospheric pressure and temperature, on the retrieved gas mixing ratio has been assessed within the OCS-lidar methodology. In addition to this theoretical work, the first experimental demonstration of the OCS-lidar methodology has been performed using a femtosecond lidar system. The latter has been entirely designed, developed and implemented in the framework of this thesis. Results show the ability of the OCS-lidar methodology to monitor the water vapor using the 4ν 720 nm absorption band. Moreover, two different experimental configurations have been proposed, depending on whether the amplitude modulation is operated on the laser pulse or on the backscattered light, i.e. at the emission, with an active amplitude modulator or at the reception, with passive optical filters. The advances in developing the corresponding infrared OCS-lidar system for methane mixing ratios measurements are described and possible outlooks are given
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Chan, Wai Nam 1964. "Quantificação e redução de emissões de gases de efeito estufa em uma refinaria de petroleo." [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/263805.
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Orientador: Arnaldo Cesar da Silva WalterDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica
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Resumo: Queima de combustíveis fósseis é a principal contribuição humana para o aquecimento global. Neste trabalho foram investigadas oportunidades de redução das emissões de gases de efeito estufa (GEE) para uma refinaria brasileira de petróleo, através das seguintes etapas: levantamento das estratégias de enfrentamento do problema adotadas por algumas empresas; seleção de uma metodologia de estimativa de emissões de GEE para companhias de óleo e gás; elaboração do inventário da refinaria nacional através do programa aplicativo SANGEA; e proposição de opções para gestão das emissões de GEE dessa refinaria. Combustão e práticas de flaring e venting são os maiores contribuintes das emissões de GEE da cadeia produtiva. Quatro opções de mitigação estão sendo exploradas pelas empresas: aumento da eficiência energética, redução de flaring e venting, mudança para fontes energéticas menos intensivas em carbono e seqüestro de carbono. Neste estudo foi mostrado que o SANGEA é uma ferramenta de estimativa adequada, pois a emissão total de GEE obtida apresentou uma diferença de 1% em relação ao valor estimado pela Petrobrás. Melhoria da eficiência energética é a principal oportunidade de redução de emissões. Para a refinaria estudada foram descritos futuros projetos da área energética que apresentaram um potencial de emissão evitada de 270.000 t CO2 /ano. Por outro lado, a instalação de novas unidades para adequação dos teores de enxofre da gasolina e do diesel resultará na emissão adicional de 208.000 t CO2 /ano. Portanto, o sucesso dos esforços para economizar energia pode ser anulado pelas exigências ambientais para adequação da qualidade dos produtos. Isto ressalta a necessidade dos formuladores de política estabelecer um balanço entre as novas exigências para combustíveis (com impactos locais) e a política de abatimento de CO2 (com impactos globais)
Abstract: Fossil fuel burning is the main human contribution to global warming. In this study, opportunities for reducing greenhouse gas (GHG) emissions were investigated for a Brazilian oil refinery, according to the following steps: survey of climate change strategies adopted by some companies; selection of a methodology for calculating GHG emissions for the petroleum industry; development of an inventory for a national oil refinery by applying SANGEA software; and proposal of options for managing GHG emissions in this refinery. Combustion, flaring and venting are the largest contributors to GHG emissions in the production chain. Four mitigation options are being explored by companies: increasing energy efficiency, flaring and venting reduction, switching to less carbon-intensive sources of energy and carbon sequestration. It was demonstrated that SANGEA is a suitable estimation tool since the calculated total GHG emission showed 1% difference compared to Petrobras estimated value. Energy efficiency improvement is the main opportunity to reduce emissions. For the case study refinery future energy saving opportunities were described and their avoided emission estimation is 270,000 metric tonnes per year of CO2. On the other hand, new process units are required to comply with the gasoline and diesel stricter sulfur specifications, producing an additional emission of 208,000 metric tones per year of CO2. Thus, the successful energy saving efforts can be nullified by environmental requirements for fuel quality. This underlines the need for policy makers to strike a balance between new fuel requirements (with local impacts) and CO2 abatement policy (with global impacts)
Mestrado
Energia, Sociedade e Meio Ambiente
Mestre em Engenharia Mecânica
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Fender, Ann-Catrin [Verfasser], Dirk [Akademischer Betreuer] Gansert, Christoph [Akademischer Betreuer] Leuschner, and Hermann [Akademischer Betreuer] Jungkunst. "The rhizosphere effects of Fagus sylvatica L. and Fraxinus excelsior L. saplings on greenhouse gas fluxes between soil and atmosphere / Ann-Catrin Fender. Gutachter: Dirk Gansert ; Christoph Leuschner ; Hermann Jungkunst. Betreuer: Dirk Gansert." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2012. http://d-nb.info/1044248874/34.
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El, yazidi Abdelhadi. "Estimation des flux de CO2 et de CH4 en France en utilisant les concentrations atmosphériques du réseau ICOS et les techniques d'assimilation de données." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLV067/document.
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Depuis la révolution industrielle, les croissances économique et démographique ont augmenté de manière exponentielle induisant l’augmentation de la combustion d’énergies fossiles, telles que le charbon, le pétrole, et le gaz naturel. La combustion de ces sources d’énergie conduit à l’émission de gaz à effet de serre, principalement le dioxyde de carbone (CO2) et le méthane (CH4), qui par leur accumulation dans l’atmosphère entraînent une augmentation de l’effet de serre. Selon le GIEC (Groupe d'experts Intergouvernemental sur l'Évolution du Climat), l’implication des émissions anthropiques dans l’augmentation de l’effet de serre est extrêmement probable avec un pourcentage de certitude qui dépasse 95%. Toutefois, l’estimation des bilans régionaux d'émissions de GES reste très incertaine. L’objectif de cette thèse est de contribuer à l’amélioration de l’estimation des bilans régionaux de GES en France, en utilisant pour la première fois les concentrations atmosphériques du CO2 et de CH4 mesurées par le réseau ICOS (Integrated Carbon Observation System) et la modélisation inverse à l’échelle régionale.Dans un premier temps, on s’est focalisé sur l’étude des concentrations mesurées de CO2, CH4 et CO (monoxyde de carbone) fournis par des stations de surface. Cette étude a pour objectif l'identification des mesures atmosphériques contaminées par les émissions locales (quelques kilomètres au tour de la station) et qui provoque ce qu’on appelle « les pics de concentrations ». Trois méthodes ont été appliquées sur des séries temporelles fournies par quatre stations du réseau ICOS, afin de déterminer leur degré de contamination. Les résultats des différentes méthodes ont été comparés entre eux, puis comparés à un inventaire de données contaminées préparé manuellement par les gestionnaires des stations. Cette comparaison a permis l’évaluation de la performance des trois méthodes pour la détection réussie des pics. À l’issue de ce travail, la méthode la plus performante a été proposée pour effectuer un nettoyage automatique des séries de mesure du réseau ICOS.Dans un deuxième temps, le modèle régional de chimie-transport CHIMERE est utilisé pour simuler les concentrations atmosphériques du CO2 et du CH4 de l’année 2014 sur un domaine centré sur la France. L’objectif de cette étude est d’étudier la sensibilité des concentrations simulées en utilisant différentes données d’entrées. Premièrement, on étudie la sensibilité des concentrations simulées par rapport au transport en utilisant deux modèles météorologiques AROME et ECMWF. Deuxièmes, on analyse la sensibilité des concentrations simulées face aux différentes cartes d’émissions. Dans cette dernière étape, on étudie les différences entre les cartes d’émissions anthropiques séparément des cartes d’émissions biogéniques. Ce travail nous permet de quantifier à la fois les erreurs liées aux transports et les erreurs liées aux flux d’émissions. La meilleure combinaison des données d’entrée va être sélectionnée pour l’étape d’inversion des flux.Dans un dernier plan, les mesures atmosphériques des concentrations de CO2 et du CH4 sont utilisées par le système d’inversion PYMAI (Berchet et coll., 2013 et 2015) afin d’estimer les bilans régionaux d'émissions des principaux GES en France. L’inversion s’est exécutée pour un mois d’hiver (janvier) et un mois d’été (juillet) en utilisant le modèle de transport CHIMERE forcé par ECMWF et les flux de surface (EDGAR et VPRM). Le résultat de ce travail permet une réduction des incertitudes des bilans nationaux à hauteur de 35 %, et la quantification les émissions de CO2 et de CH4 à l'échelle nationale et régionale. Par contre, cette inversion ne contraint que partiellement les flux d’émissions. Cependant, la question sur l’efficacité de la quantité d’informations disponibles ressort à nouveauSince the industrial revolution, the economic and the demographic growths have increased exponentially,leading to an enhancement of the fossil fuels combustion, such as coal, oil, and natural gas. Consumingthese source of energy amplifies the greenhouse gas emissions, mainly carbon dioxide (CO2) and methane(CH4), whose accumulation in the atmosphere lead to the increase of the greenhouse effect. According tothe 5th assessment report of the Intergovernmental Panel on Climate Change (IPCC), it is extremely likely(95-100% of certainty) that the observed increase in the greenhouse effect is related to the increase of theanthropogenic emissions. However, the estimations of the GHG budget at the regional and the nationalscales remains highly uncertain. The aim of this thesis is to improve the estimation of the CO2 and CH4fluxes in France, using data assimilation techniques and atmospheric measurements provided by theIntegrated Carbon Observation System (ICOS) network.The first phase focuses on analyzing the measured CO2, CH4, and CO (Carbon monoxide) atmosphericconcentrations provided by surface monitoring stations. This study is concerned with the problem ofidentifying atmospheric data influenced by local emissions that can result in spikes in the GHG time series.Three methods are implemented on continuous measurements of four contrasted atmospheric sites. The aimof this analysis is to evaluate the performance of the used methods for the correctly detect the contaminateddata. This work allows us to select the most reliable method that was proposed to perform daily spikedetection in the ICOS Atmospheric Thematic Centre Quality Control (ATC-QC) software.Secondly, we simulate the atmospheric concentrations of CO2 and CH4 using the chemistry transport modelCHIMERE in a domain centered over France for the year 2014. The objective of this study is to evaluate thesensitivity of simulated concentrations using different input data (sensitivity to the meteorological transportand sensitivity to the surface fluxes). This work led to the quantification of both the transport and surfacefluxes errors based on the combination of different simulations. Thus, the most reliable combination of thebest input data was selected for the flux inversion study.Lastly, the measured CO2 and CH4 concentrations are used by the PYMAI inversion system (Berchet et al.,2013 and 2015) in order to estimate the CO2 and CH4 fluxes in France. The Inversion is performed for onemonth in winter (January) and one month in summer (July), using the transport model CHIMERE. Theinversion results have provided very interesting results for the regional estimation of the CO2 and CH4surface fluxes in France with an uncertainty reduction that may attain 35% of the national totals
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Lin, Xin. "Variabilité des concentrations atmosphériques de gaz à effet de serre et inversion des flux de méthane en Asie du Sud et de l’Est." Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLV076.
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L’Asie du Sud et de l'Est (ASE) est la première région du monde émettrice de gaz à effet de serre (GES) au cours des dernières décennies. Cependant, l’estimation des bilans régionaux d'émissions de GES est encore incertaine que ce soit par l’approche ‘bottom-up’ ou par l’approche ‘top-down’. L’objectif de cette thèse est de contribuer à une meilleure connaissance des bilans régionaux des émissions de GES en ASE, en utilisant les concentrations atmosphériques de GES mesurées dans un réseau de station de surface et la modélisation inverse à l’échelle régionale. Dans un premier temps, la thèse présente les mesures de CO2, CH4, N2O, SF6, CO, et H2 sur les échantillons réguliers prélevés àHanle, Pondichéry et Port Blair, trois nouveaux sites établis en Inde dans le cadre d’une collaboration franco-indienne. L’analyse des concentrations des gaz traces a permis de caractériser les contributions relatives des flux naturel et anthropique, et de la circulation atmosphérique associée à la mousson dans le sous-continent indien. Cette étude meten évidence le potentiel des nouvelles stations de mesure atmosphérique pour mieux contraindre les estimations de flux régionaux de GES. Dans un deuxième temps, un modèle global de chimie-transport LMDzINCA, avec un ‘zoom’ focalisé sur l’ASE (de résolution horizontale ~50 km) est utilisé pour simuler les champs de concentration de CO2 et CH4. Les concentrations simulées sont évaluées par rapport aux mesures de 30 stations réparties en ASE et dans les régions adjacentes. Le modèle de transport en version zoomée reproduit relativement bien les variabilités des mesures de CO2 et CH4, et améliore significativement les variations de CH4 par rapport au modèle standard de basse résolution sur le domaine d’étude. Enfin, les mesures des concentrations de CH4 des réseaux régionaux sont utilisées dans le système d’inversion PYVAR-LMDz-SACS avec les grilles zoomées, pour estimer les émissions de CH4 en ASE en 2010.Plusieurs scénarios sont réalisés afin de tester la sensibilité de l’inversion à différentes configurations des émissions a priori et des observations utilisées. L’inversion atmosphérique induit une réduction significative des émissions en comparaison aux inventaires a priori en Asie de l’Est (14-20%), en particulier en Chine du Nord (20-35%). L’estimation des émissions de CH4 est sensible à l’incertitude dans les bilans ‘bottom-up’ des émissions anthropiques en Asie de l’Est, particulièrement à la représentation très incertaine des sources localisées des mines de charbon en Chine du NordSouth and East Asia (SEA) is the world’s largest anthropogenic greenhouse gas (GHG) emitting region during the recent decades, yet estimates of regional GHG budgets remain uncertain either from bottom-up or top-down approaches. The aim of the thesis is to improve understanding of GHG budgets in SEA through atmospheric measurements from surface stations and regional inverse modeling. The first part of the thesis presents measurements of CO2, CH4, N2O, SF6, CO, and H2 from regular flask sampling at Hanle, Pondicherry and Port Blair, three new Indian stations established in the framework of the Indo-French collaboration. Time series of tracer concentrations are analyzed and related to variations in natural/anthropogenic fluxes and monsoon circulations in the Indian sub-continent, showing potential of these stations to constrain estimates of regional GHG fluxes. The second part of the study involves simulation of CO2 and CH4 using a zoomed version of the global chemistry transport model LMDzINCA, with a horizontal resolution of ~50km over SEA. Model performance is evaluated against observations from 30 surface stations in SEA and adjacent regions. The zoomed transport model shows the ability to reasonably reproduce CO2 and CH4 variabilities at stations, and improves model performance for CH4 compared to the standard model version within the zoomed region. Lastly, the CH4 emissions in SEA are retrieved for the year 2010 using atmospheric surface stations and a Bayesian inversion system PYVAR-LMDz-SACS with the zoomed model grids. Different setups of prior information are used in inversions to account for uncertainties in bottom-up inventories of anthropogenic emissions. Significant reduction in emissions compared to the prior estimates is found for East Asia (by 14–20%), particularly in North China (by 20–35%). The inverted CH4 budgets are sensitive to prior anthropogenic emissions in East Asia, especially in North China where coal mine hotspots dominate the budgets yet their representation is highly uncertain among different inventories
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Cotovicz, Junior Luiz Carlos. "Concentrations et échanges atmosphériques de gaz carbonique (CO2) et de méthane (CH4) dans un estuaire tropical eutrophe (Baie de Guanabara, RJ, Brésil)." Thesis, Bordeaux, 2016. http://www.theses.fr/2016BORD0034/document.
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Les taux de production, transformation, émission et sédimentation de carbone à l’interface continent-océan sont significatifs à l’échelle globale, mais encore sujets à de fortes incertitudes en particulier dans les régions tropicales. De même, l’augmentation des concentrations atmosphériques de dioxyde de carbone (CO2) et de méthane (CH4), oblige la communauté scientifique à développer des méthodes pour quantifier les concentrations et les flux dans la zone côtière. Cette thèse se présente sous forme de 5 chapitres. Les chapitres 1 et 2 présentent une introduction générale et l’état de l’art sur la dynamique du CO2 et du CH4 dans les systèmes estuariens. Le chapitre 3 décrit le système de mesure en temps réel de la pression partielle en CO2 (pCO2), ainsi qu’une comparaison de ces mesures directes avec les estimations indirectes à partir de l’Alcalinité et du pH de l’eau dans deux estuaires brésiliens contrastés : la baie de Guanabara, (Etat de Rio de Janeiro), et l’estuaire du fleuve São Francisco (Etat d’Alagoas). Dans la baie de Guanabara, un estuaire à dominance marine et fortement impacté par les activités anthropiques, les valeurs de pCO2 calculées et mesurées sont très cohérentes (R2 = 0.95, p < 0.0001). Au contraire, dans l’estuaire du São Francisco, où la totalité du gradient salin a été échantillonné, des surestimations importantes des pCO2 calculées par rapport aux valeurs mesurées ont été observées dans certains échantillons d’eau douce ; la surestimation moyenne pour l’estuaire était de 74%, atteignant des valeurs extrêmes de 737%. Ces erreurs sont attribuées à une contribution d’alcalinité organique et à un faible pouvoir tampon dans les eaux douces aux pH acides et aux faibles valeurs d’alcalinité. Les chapitres 4 et 5 présentent les variations spatio-temporelles des concentrations et flux de CO2 et de CH4 à l’interface eau-atmosphère dans la baie de Guanabara. L’étude a été conduite entre Avril 2013 et Avril 2014, avec des mesures continue de pCO2, température, salinité, fluorescence e oxygène dissous (OD). Un échantillonnage discret a été réalisé pour déterminer les concentrations en CH4, Chlorophylle et nutriments inorganiques dissous. Les concentrations de CO2 et CH4 variaient entre 22 et 3715 ppmv et entre 18 et 10350 nmol L-1, respectivement. Des sous-saturations marquées en CO2 prédominaient dans les eaux peu profondes, confinées et stratifiées thermiquement principalement en été, tandis que les sursaturations en CO2 étaient restreintes aux régions proximales aux débouchés de fleuves et aux rejets d’eaux usées urbaines. Les concentrations en CO2 variaient aussi à l’échelle diurne en fonction de l’activité de photosynthése et de respiration, avec des maximaux en fin de nuit. Tous les échantillons étaient sursaturés en CH4, avec des concentrations maximales à proximité des rejets urbains. Cette distribution suggère que la production de CH4 dans les sédiments de la baie est faible du fait de la compétition entre sulfato-réduction et méthanogénèse, la majorité du CH4 provenant d’apports en provenance du réseau d’égout. Contrairement à la plupart des systèmes estuariens, la baie de Guanabara se comporte comme un puits de CO2, favorisé par de fortes radiations lumineuses, une stratification thermique et une grande disponibilité en nutriments, qui génèrent des floraisons phytoplanctoniques et un métabolisme autotrophe de 52,1 mol C m-2 an-1. [...]The production, transformation, emission and burial of carbon at the land-ocean interface are globally significant, but rather poorly quantified in tropical regions. The increasing atmospheric concentrations of dioxide carbon (CO2) and methane (CH4) alerts to the importance and necessity of monitoring and quantifying the concentrations and fluxes of these greenhouse gases at coastal zone. The present doctoral thesis was divided into several chapters. Chapter 1 presents a general introduction to the thesis. Chapter 2 corresponds to a general introduction which focuses on the state of art of knowledge of the thesis subject, dealing with the CO2 and CH4 dynamics in estuaries. Chapter 3 describes the system applied for the online and continuous measurements of the aquatic partial pressure of CO2 (pCO2) and compares its estimate between the method of the continuous measurements with indirect estimates based on calculations with total alkalinity and pH in two contrasting Brazilian estuaries. One being the marine dominated and highly anthropogenically disturbed Guanabara Bay (State of Rio de Janeiro, SE-Brazil) and the other, the oligotrophic Sao Francisco River Estuary (State of Alagoas, NE-Brazil), impacted by dams. For Guanabara Bay, the measured and calculated pCO2 values showed an excellent agreement (R2 = 0.95, p < 0.0001). In contrast, the Sao Francisco estuary, showed good agreements between both methods in the estuarine mixing zone but not for it´s freshwater end member samples, which yielded substantial overestimations for the calculated pCO2. The average overestimation was 72%, reaching 737%. These discrepancies were attributed to the interference of organic alkalinity in the calculations particular in acid, poorly buffered freshwaters. Chapters 4 and 5 correspond to the part of this study, addressing the results of the temporal and spatial variations of CO2 and CH4 concentrations and atmospheric exchanges in Guanabara Bay. The study was conducted between April 2013 and April 2014, with continuous on line monitoring along trajectories of pCO2, temperature, salinity, fluorescence and dissolved oxygen. In addition, discrete sampling was performed at fixed stations along the trajectories for CH4, Chlorophyll a and dissolved inorganic nutrients. The annual concentrations of CO2 and CH4 ranged between 22-3715 ppmv and 18-10350 nmol L-1, respectively. Marked undersaturations of pCO2 were prevalent in shallow, confined and stratified waters especially at summertime, whereas oversaturations were restricted to the vicinity of the polluted river mouths and effluent discharge. The CO2 presented diurnal variations related to the processes of photosynthesis and respiration, with higher values at nigh-time period. CH4 was oversaturated in all samples, with higher concentrations primarily in the polluted regions. Methanogenesis seemed to be low in the sampled regions due to the competition with sulphate-reduction, with the major part of the CH4 sustained by allochthonous sources, derived from the sewage network. In contrast to the major part of the world´s estuarine systems, Guanabara Bay was considered a strong sink of CO2 due to concomitant effects of high photosynthetically active radiation intensity (PAR), thermal stratification and net autotrophy (autotrophic metabolism of 52.1 mol C m-2 yr-1). [...]
As taxas de produção, transformação, emissão e sedimentação de carbono na interface terra-mar são significantes globalmente, porém pobremente quantificadas nas regiões tropicais. O aumento acelerado nas concentrações atmosféricas de dióxido de carbono (CO2) e metano (CH4) alerta a importância do monitoramento e quantificação das concentrações e fluxos desses gases do efeito estufa na zona costeira. A redação da presente tese foi separada em capítulos. Os capítulos 1 e 2 apresentam a introdução geral do trabalho e o estado da arte do conhecimento da temática da tese, sobre a dinâmica de CO2 e CH4 em estuários. O capítulo 3 contém a descrição do sistema de medição contínua e on-line da pressão parcial do CO2 (pCO2) e comparações entre as medições contínuas com estimativas indiretas calculadas a partir da alcalinidade total (AT) e pH da água em dois estuários contrastantes: a Baía de Guanabara, Rio de Janeiro, e o estuário do Rio São Francisco, AL. Na Baía de Guanabara, um estuário dominado pela forçante marinha e altamente impactado por atividades antrópicas, os valores calculados e medidos da pCO2 mostraram excelente concordância (R2 = 0.95, p < 0.0001). Em contraste, no estuário do Rio São Francisco, onde o gradiente salino completo foi amostrado, importantes superestimativas foram verificadas nos valores calculados em algumas amostras de água doce. A superestimativa média foi de 72%, chegando ao valor extremo de 737%. Esses erros foram atribuídos à contribuição da alcalinidade orgânica e à baixa capacidade de tamponamento do sistema carbonato sob condições de água doce, de baixo pH e baixa AT. Os capítulos 4 e 5 apresentam os resultados das variações temporais e espaciais nas concentrações e fluxos de CO2 e CH4 na interface água-atmosfera na Baía de Guanabara. O estudo foi conduzido entre Abril de 2013 e Abril de 2014 com monitoramento contínuo da pCO2, temperatura, salinidade, fluorescência e oxigênio dissolvido (OD). Amostragens discretas foram realizadas para CH4, clorofila a e nutrientes inorgânicos dissolvidos. As concentrações anuais de CO2 e CH4 variaram entre 22-3715 ppmv e 18-10350 nmol L-1, respectivamente. Marcantes subsaturações da pCO2 na água em relação à pCO2 atmosférica foram prevalentes em águas rasas, confinadas e termicamente estratificadas principalmente no verão, enquanto supersaturação foi restrita às proximidades da desembocadura de rios poluídos e efluentes de esgotos. O CO2 também apresentou variações diuturnas em função dos processos de fotossíntese e respiração, com maiores valores no período noturno. O CH4 apresentou sobressaturação em todas as amostras, com as concentrações mais altas próximas de localidades com maior influência antrópica. A produção de metano pareceu ser pequena na região amostrada em função da competição com a redução de sulfato, sendo a maior parte do CH4 sustentada por fontes alóctones (rios poluídos e esgoto doméstico). Contrariamente à maioria dos sistemas estuarinos, a Baía de Guanabara foi considerada um sumidouro anual de CO2 em função da concomitância entre alta incidência de radiação fotossinteticamente ativa (PAR), estratificação térmica e alta disponibilidade de nutrientes, que promoveram grandes florações de fitoplâncton e autotrofia (metabolismo autotrófico de 52,1 mol C m-2 ano-1)
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El, yazidi Abdelhadi. "Estimation des flux de CO2 et de CH4 en France en utilisant les concentrations atmosphériques du réseau ICOS et les techniques d'assimilation de données." Electronic Thesis or Diss., Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLV067.
Full textAbstract:
Depuis la révolution industrielle, les croissances économique et démographique ont augmenté de manière exponentielle induisant l’augmentation de la combustion d’énergies fossiles, telles que le charbon, le pétrole, et le gaz naturel. La combustion de ces sources d’énergie conduit à l’émission de gaz à effet de serre, principalement le dioxyde de carbone (CO2) et le méthane (CH4), qui par leur accumulation dans l’atmosphère entraînent une augmentation de l’effet de serre. Selon le GIEC (Groupe d'experts Intergouvernemental sur l'Évolution du Climat), l’implication des émissions anthropiques dans l’augmentation de l’effet de serre est extrêmement probable avec un pourcentage de certitude qui dépasse 95%. Toutefois, l’estimation des bilans régionaux d'émissions de GES reste très incertaine. L’objectif de cette thèse est de contribuer à l’amélioration de l’estimation des bilans régionaux de GES en France, en utilisant pour la première fois les concentrations atmosphériques du CO2 et de CH4 mesurées par le réseau ICOS (Integrated Carbon Observation System) et la modélisation inverse à l’échelle régionale.Dans un premier temps, on s’est focalisé sur l’étude des concentrations mesurées de CO2, CH4 et CO (monoxyde de carbone) fournis par des stations de surface. Cette étude a pour objectif l'identification des mesures atmosphériques contaminées par les émissions locales (quelques kilomètres au tour de la station) et qui provoque ce qu’on appelle « les pics de concentrations ». Trois méthodes ont été appliquées sur des séries temporelles fournies par quatre stations du réseau ICOS, afin de déterminer leur degré de contamination. Les résultats des différentes méthodes ont été comparés entre eux, puis comparés à un inventaire de données contaminées préparé manuellement par les gestionnaires des stations. Cette comparaison a permis l’évaluation de la performance des trois méthodes pour la détection réussie des pics. À l’issue de ce travail, la méthode la plus performante a été proposée pour effectuer un nettoyage automatique des séries de mesure du réseau ICOS.Dans un deuxième temps, le modèle régional de chimie-transport CHIMERE est utilisé pour simuler les concentrations atmosphériques du CO2 et du CH4 de l’année 2014 sur un domaine centré sur la France. L’objectif de cette étude est d’étudier la sensibilité des concentrations simulées en utilisant différentes données d’entrées. Premièrement, on étudie la sensibilité des concentrations simulées par rapport au transport en utilisant deux modèles météorologiques AROME et ECMWF. Deuxièmes, on analyse la sensibilité des concentrations simulées face aux différentes cartes d’émissions. Dans cette dernière étape, on étudie les différences entre les cartes d’émissions anthropiques séparément des cartes d’émissions biogéniques. Ce travail nous permet de quantifier à la fois les erreurs liées aux transports et les erreurs liées aux flux d’émissions. La meilleure combinaison des données d’entrée va être sélectionnée pour l’étape d’inversion des flux.Dans un dernier plan, les mesures atmosphériques des concentrations de CO2 et du CH4 sont utilisées par le système d’inversion PYMAI (Berchet et coll., 2013 et 2015) afin d’estimer les bilans régionaux d'émissions des principaux GES en France. L’inversion s’est exécutée pour un mois d’hiver (janvier) et un mois d’été (juillet) en utilisant le modèle de transport CHIMERE forcé par ECMWF et les flux de surface (EDGAR et VPRM). Le résultat de ce travail permet une réduction des incertitudes des bilans nationaux à hauteur de 35 %, et la quantification les émissions de CO2 et de CH4 à l'échelle nationale et régionale. Par contre, cette inversion ne contraint que partiellement les flux d’émissions. Cependant, la question sur l’efficacité de la quantité d’informations disponibles ressort à nouveauSince the industrial revolution, the economic and the demographic growths have increased exponentially,leading to an enhancement of the fossil fuels combustion, such as coal, oil, and natural gas. Consumingthese source of energy amplifies the greenhouse gas emissions, mainly carbon dioxide (CO2) and methane(CH4), whose accumulation in the atmosphere lead to the increase of the greenhouse effect. According tothe 5th assessment report of the Intergovernmental Panel on Climate Change (IPCC), it is extremely likely(95-100% of certainty) that the observed increase in the greenhouse effect is related to the increase of theanthropogenic emissions. However, the estimations of the GHG budget at the regional and the nationalscales remains highly uncertain. The aim of this thesis is to improve the estimation of the CO2 and CH4fluxes in France, using data assimilation techniques and atmospheric measurements provided by theIntegrated Carbon Observation System (ICOS) network.The first phase focuses on analyzing the measured CO2, CH4, and CO (Carbon monoxide) atmosphericconcentrations provided by surface monitoring stations. This study is concerned with the problem ofidentifying atmospheric data influenced by local emissions that can result in spikes in the GHG time series.Three methods are implemented on continuous measurements of four contrasted atmospheric sites. The aimof this analysis is to evaluate the performance of the used methods for the correctly detect the contaminateddata. This work allows us to select the most reliable method that was proposed to perform daily spikedetection in the ICOS Atmospheric Thematic Centre Quality Control (ATC-QC) software.Secondly, we simulate the atmospheric concentrations of CO2 and CH4 using the chemistry transport modelCHIMERE in a domain centered over France for the year 2014. The objective of this study is to evaluate thesensitivity of simulated concentrations using different input data (sensitivity to the meteorological transportand sensitivity to the surface fluxes). This work led to the quantification of both the transport and surfacefluxes errors based on the combination of different simulations. Thus, the most reliable combination of thebest input data was selected for the flux inversion study.Lastly, the measured CO2 and CH4 concentrations are used by the PYMAI inversion system (Berchet et al.,2013 and 2015) in order to estimate the CO2 and CH4 fluxes in France. The Inversion is performed for onemonth in winter (January) and one month in summer (July), using the transport model CHIMERE. Theinversion results have provided very interesting results for the regional estimation of the CO2 and CH4surface fluxes in France with an uncertainty reduction that may attain 35% of the national totals
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Lin, Xin. "Variabilité des concentrations atmosphériques de gaz à effet de serre et inversion des flux de méthane en Asie du Sud et de l’Est." Electronic Thesis or Diss., Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLV076.
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L’Asie du Sud et de l'Est (ASE) est la première région du monde émettrice de gaz à effet de serre (GES) au cours des dernières décennies. Cependant, l’estimation des bilans régionaux d'émissions de GES est encore incertaine que ce soit par l’approche ‘bottom-up’ ou par l’approche ‘top-down’. L’objectif de cette thèse est de contribuer à une meilleure connaissance des bilans régionaux des émissions de GES en ASE, en utilisant les concentrations atmosphériques de GES mesurées dans un réseau de station de surface et la modélisation inverse à l’échelle régionale. Dans un premier temps, la thèse présente les mesures de CO2, CH4, N2O, SF6, CO, et H2 sur les échantillons réguliers prélevés àHanle, Pondichéry et Port Blair, trois nouveaux sites établis en Inde dans le cadre d’une collaboration franco-indienne. L’analyse des concentrations des gaz traces a permis de caractériser les contributions relatives des flux naturel et anthropique, et de la circulation atmosphérique associée à la mousson dans le sous-continent indien. Cette étude meten évidence le potentiel des nouvelles stations de mesure atmosphérique pour mieux contraindre les estimations de flux régionaux de GES. Dans un deuxième temps, un modèle global de chimie-transport LMDzINCA, avec un ‘zoom’ focalisé sur l’ASE (de résolution horizontale ~50 km) est utilisé pour simuler les champs de concentration de CO2 et CH4. Les concentrations simulées sont évaluées par rapport aux mesures de 30 stations réparties en ASE et dans les régions adjacentes. Le modèle de transport en version zoomée reproduit relativement bien les variabilités des mesures de CO2 et CH4, et améliore significativement les variations de CH4 par rapport au modèle standard de basse résolution sur le domaine d’étude. Enfin, les mesures des concentrations de CH4 des réseaux régionaux sont utilisées dans le système d’inversion PYVAR-LMDz-SACS avec les grilles zoomées, pour estimer les émissions de CH4 en ASE en 2010.Plusieurs scénarios sont réalisés afin de tester la sensibilité de l’inversion à différentes configurations des émissions a priori et des observations utilisées. L’inversion atmosphérique induit une réduction significative des émissions en comparaison aux inventaires a priori en Asie de l’Est (14-20%), en particulier en Chine du Nord (20-35%). L’estimation des émissions de CH4 est sensible à l’incertitude dans les bilans ‘bottom-up’ des émissions anthropiques en Asie de l’Est, particulièrement à la représentation très incertaine des sources localisées des mines de charbon en Chine du NordSouth and East Asia (SEA) is the world’s largest anthropogenic greenhouse gas (GHG) emitting region during the recent decades, yet estimates of regional GHG budgets remain uncertain either from bottom-up or top-down approaches. The aim of the thesis is to improve understanding of GHG budgets in SEA through atmospheric measurements from surface stations and regional inverse modeling. The first part of the thesis presents measurements of CO2, CH4, N2O, SF6, CO, and H2 from regular flask sampling at Hanle, Pondicherry and Port Blair, three new Indian stations established in the framework of the Indo-French collaboration. Time series of tracer concentrations are analyzed and related to variations in natural/anthropogenic fluxes and monsoon circulations in the Indian sub-continent, showing potential of these stations to constrain estimates of regional GHG fluxes. The second part of the study involves simulation of CO2 and CH4 using a zoomed version of the global chemistry transport model LMDzINCA, with a horizontal resolution of ~50km over SEA. Model performance is evaluated against observations from 30 surface stations in SEA and adjacent regions. The zoomed transport model shows the ability to reasonably reproduce CO2 and CH4 variabilities at stations, and improves model performance for CH4 compared to the standard model version within the zoomed region. Lastly, the CH4 emissions in SEA are retrieved for the year 2010 using atmospheric surface stations and a Bayesian inversion system PYVAR-LMDz-SACS with the zoomed model grids. Different setups of prior information are used in inversions to account for uncertainties in bottom-up inventories of anthropogenic emissions. Significant reduction in emissions compared to the prior estimates is found for East Asia (by 14–20%), particularly in North China (by 20–35%). The inverted CH4 budgets are sensitive to prior anthropogenic emissions in East Asia, especially in North China where coal mine hotspots dominate the budgets yet their representation is highly uncertain among different inventories
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Penteado, Luis Fernando de Freitas. "Os créditos de emissões atmosféricas reduzidas e a responsabilidade civil ambiental." Pontifícia Universidade Católica de São Paulo, 2007. https://tede2.pucsp.br/handle/handle/7731.
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Previous issue date: 2007-10-08Although the problem related to the weather change has been widespread only in the last decades, it is not recent the concern of the international community in the adoption of measures for the mitigation of this change in the ecosystem balance. The Kyoto Protocol, however, comes as the concrete awareness of the need of acting towards the reduction of the greenhouse effect, which causes such changes in our weather, noticed, mainly, through the global warming. The main means designed by that international treaty is the possibility of compensating the emissions of the gases accountable for the greenhouse effect (GEG Greenhouse Effect Gases), which is possible only through the transaction of the Credits of Emission Reduction - CERs, commonly known as Carbon Credits. Its example was followed, individually, by several other countries, being its idea adopted, even by Brazil, most accurately by São Paulo Estate, which improved its concept in the reduction of the concentration in the atmosphere of some polluting gases and of particulated material. However, a lot is asked about the compatibility of the above mentioned Protocol inside the principles and main regulations of our Environmental Law, and also, about what would be the environmental civil responsibility of the people engaged in the projects, related to a possible not fulfilling of the reduction of the emissions, as declared in each case. In this paper, we will demonstrate the perfect compatibility among the projects that give rise to the getting of the Credits of Reduced Atmospheric Emissions and our main laws related to the environment protection, as well as to the Environmental Law Principles. Finally, we will also, as an important part of this paper, analyses the environmental civil responsibility of the people in charge of keeping the commitments made when a project is implemented, aiming at obtaining the Credits of the Reduced Atmospheric Emissions
Apesar de somente nas últimas décadas o problema relativo às mudanças climáticas ter ganhado a repercussão que lhe é devida, não é de agora a preocupação da Comunidade Internacional na adoção de medidas para mitigação dessa alteração ao equilíbrio ecossistêmico. O Protocolo de Quioto representa a concretização da necessidade de se agir de modo a reduzir o chamado efeito estufa, causador de tais mudanças em nosso clima, sentidas, principalmente, com o aquecimento global. O principal instrumento idealizado por este Tratado Internacional encontra-se na possibilidade de se compensar as emissões dos gases responsáveis pelo efeito estufa (GEE Gases de Efeito Estufa), ato que é possível apenas via transação das Certidões de Redução de Emissões - RCEs, popularmente conhecidas como Créditos de Carbono. Seu exemplo foi seguido ainda individualmente, por outros diversos países, chegando sua idéia a ser adotada inclusive pelo Brasil, mais precisamente pelo Estado de São Paulo, que aprimorou seu conceito na redução da concentração na atmosfera de alguns gases poluentes e de material particulado. Entretanto, muito se questiona doutrinariamente acerca da compatibilidade do referido instrumento com nosso Direito Ambiental, princípios e principais normas, e ainda sobre qual seria a responsabilidade civil ambiental daqueles envolvidos nos projetos, frente a um eventual não cumprimento da redução das emissões, conforme declarado em cada caso. Demonstrar-se-á, ao longo do texto, a perfeita compatibilidade entre os projetos que dão ensejo à obtenção dos Créditos de Emissões Atmosféricas Reduzidas e as nossas principais leis relativas à proteção do meio ambiente, bem como aos princípios de Direito Ambiental. Por fim, sendo ainda o foco principal do presente estudo, será analisada a responsabilidade civil ambiental dos responsáveis pela manutenção dos compromissos acordados quando da implementação de um projeto visando à obtenção dos Créditos de Emissões Atmosféricas Reduzidas
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Shaw, Justin Masten. "Building a greenhouse global warming data and their origins /." 1991. http://catalog.hathitrust.org/api/volumes/oclc/86121020.html.
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