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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
261

Estoque de carbono do solo e fluxo de gases de efeito estufa no cultivo do café / SOIL CARBON STOCK AND GREENHOUSE GASES FLUXES UNDER COFFEE CULTIVATION

Belizario, Maísa Honorio 05 March 2013 (has links)
O café é uma das principais culturas exploradas no Brasil, e está entre as mais importantes commodities agrícolas de exportação. A demanda por produtos agrícolas sustentáveis é cada vez maior, questão especialmente importante para a competitividade dos produtos de exportação. Portanto, conhecer os impactos das emissões de gases do efeito estufa (GEE) é fundamental para qualquer cultura agrícola, assim como estudar o seu manejo para detectar alternativas mitigadoras. O objetivo deste estudo foi determinar o estoque de carbono no solo e o fluxo de gases de feito estufa no cultivo do café. Para tal foram avaliados o estoque de carbono do solo devido à conversão do uso da terra sob vegetação de Cerrado para a cultura do café; o uso de corretivo agrícola e sua influencia no fluxo de CO2, assim como a influência do uso de fertilizantes nitrogenados na emissão de N2O. O carbono (C) do solo foi determinado para o solo original de cerrado (controle) e em áreas convertidas há 37, 15 e 8 anos, além de duas áreas que receberam adição 22.684 e 16.845 kg ha-1de composto orgânico em 2006 (CRI) e 2010 (CRII), respectivamente. O estoque de C no solo foi maior na área Café 37 (91,34 Mg C ha-1) e o menor para o Cerrado (66,87 Mg C ha-1) a 0-30cm. As áreas com Café 15, 8 anos, CRI e CRII não apresentaram diferença entre si, com estoque de carbono no solo de 85,21, 85,75, 73,29 e 76,95, Mg C ha-1 respectivamente. Após a conversão do solo para a produção de café, há um aumento considerável no estoque de C, porém ao longo do tempo este valor tende a decrescer, provavelmente por conta de práticas de manejo. O nitrogênio (N) é o nutriente exigido em grande quantidade pela cultura do café e é apontado dentre os fertilizantes que mais contribuem com a emissão de GEE na agricultura. A fim de se conhecer o fluxo de emissão das diferentes alternativas de adubação nitrogenada, avaliou-se o nitrato de cálcio (NC), nitrato de amônio (NA), ureia (UR) e ureia-NBPT (NBPT®), para dose única (100 kg ha-1) e parcelada (2 x 50 kg ha-1). A ureia em dose única foi a fonte de maior emissão (125,12 mg N-N2O m-2) e o nitrato de cálcio parcelado foi a de menor (1,93mg N-N2O m-2). O uso da calagem é essencial para corrigir a fertilidade de solos ácidos, como é o caso da maioria dos solos de cerrado. A calagem é uma importante fonte emissora de CO2 na atividade agrícola. Para se conhecer o fluxo de emissão da calagem, avaliou-se uma área com calcário recém aplicado e outra área após 5 anos da calagem. Os fluxos acumulados foram de 64,7 e 58,7 g de C-CO2 m-2, respectivamente. A área que recebeu calcário recentemente obteve maior emissão por efeitos indiretos. Buscando atender a exigências de sustentabilidade avaliou-se a emissão do sistema de produção por cada saca de café (60 kg). Para tal foram utilizados dados de combustível, fertilizantes nitrogenados, adubo orgânico, calcário e eletricidade. A fazenda emitiu um total de 2.698 t CO2 equivalente de GEE durante dois anos agrícolas. A fonte que mais contribuiu foi o uso óleo diesel (1.407 t CO2eq) e a menor foi a eletricidade (41 t CO2eq). Para produzir uma saca de café foram emitidos 0,68 kg de CO2eq kg-1 de café. / The coffee is one of the main crops grown in Brazil, and is its most important agricultural export commodities. The demand for sustainable agricultural products is increasing, especially important issue for the competitiveness of export products. Therefore, knowing the impacts of emissions of greenhouse gases (GHG) is critical for any crop, as well as studying their management to detect mitigation alternatives. The aim of this study was to determine the soil carbon stock and flow of greenhouse gases made in the cultivation of coffee. The studies comprised the evaluation of the conversion of land use Cerrado vegetation for coffee, use of liming and its influence on the flux of CO2, as well as the influence of the use of nitrogen fertilizers on N2O emission. Carbon (C) of the soil was determined for the original Cerrado soil (control) and in areas converted for 37, 15 and 8 years, and also two areas who received addition of 22.684 e 16.845 kg ha-1 organic compound in 2006 and 2010, respectively. The highest levels of carbon were to coffee 37 to 0-5 cm in Li, and the layers 5-10, 10-20 cm in Eli C stocks in the soil was higher in the coffee 37 (91.34 Mg C ha-1) and the lowest for the Cerrado (66.87 Mg C ha-1) at 0-30cm. Areas with coffee 15, 8, and CRI CRII did not differ among themselves, with soil carbon stock of 85.21, 85.75, 73.29 and 76.95 Mg C ha-1, respectively. After the conversion of land for coffee production, there is a considerable increase in the stock of C, but over time this value tends to decrease, probably due to management practices. Nitrogen (N) is the nutrient required in large quantity by the coffee culture and is named among the fertilizers that contribute most to GHG emissions in agriculture. In order to meet the emission flux of alternative nitrogen fertilization was evaluated calcium nitrate (CN), ammonium nitrate (AN), urea (UR) and urea NBPT (NBPT®), full dose (100 kg ha-1) and split dose (2 x 50 kg ha-1). Urea full dose was increased emission source (125.12 mg N2O-N m-2) and calcium nitrate was less parceled (1.93 mg N2O-N m-2). The use of lime is essential to correct the fertility of acid soils, a situation typical of most Cerrado soils. Liming is an important emission source of CO2 in agricultural activity. To know the flow of issuance of liming, evaluated a limestone area with freshly applied and another 5 years after liming. The accumulated flows were 64.7 and 58.7 g CO2-C m-2, respectively. The area was limed recently gained greater flow issue. Seeking to meet the requirements of sustainability evaluated the issue of the production system for every bag of coffee (60 kg). For such data were used fuel, nitrogen fertilizer, organic fertilizer, limestone and electricity. For such data were used fuel, nitrogen fertilizer, organic fertilizer, limestone and electricity. The farm issued a total of 2.698 t of CO2 equivalent GHG during a two crop years. The source that contributed most was the use of diesel (1.407 t CO2eq) and the lowest was electricity (41 t CO2eq). To produce a bag of coffee were issued 0.68 kg CO2eq kg-1 coffee.
262

Sculpture et cinéma : emprunts et perméabilités dans le champ de l'art contemporain et du cinéma / Sculpture and cinema : borrowings and interrelationships in the field of contemporary art and cinema

Honore, Thibault 16 January 2015 (has links)
La rencontre entre le cinéma et les arts du volume relève d’un principe de perméabilité. Le travail des cinéastes, qui se sont essayés à l’installation, témoigne de phénomènes d’hybridations connexes. Si le cinéma gagne l’espace d’exposition, c’est pour y retrouver les données séculaires de sa monstration. Le septième art voit dans sa déterritorialisation vers l’objet d’art tridimensionnel, l’expression réaffectée de son histoire. Le déplacement du cinéma dans le champ des œuvres d’art en volume doit donc être interrogé selon un principe de survivance. En feignant d’amortaliser les êtres qu’il capture, le cinéma trouve dans la sculpture un moyen de présentifier la mort. Dans notre travail plastique, cette entreprise passe par un procédé formel reconnaissable : le renversement. De ce geste plastique, dont nous postulons qu’il est métonymique d’une forme d’enfouissement, naît l’idée que le cinéma et la sculpture s’inscrivent tous deux dans un régime funéraire de l’art. / The meeting of cinema and sculpture must be analyzed through a principle of interrelationships. The work of movie directors, who tried to realize sculptures and installations, proves similar phenomena of hybridization. When cinema leaves the theatre for an exhibition, it is also to find again, with the updating of new plastic forms, the secular data of its screening. With its transfer towards the sculpture the cinematographic art acquires the new expression of its personal history. Knowing this, the movement of cinema towards sculpture must also be questioned in the light of a principle of survival. By pretending to a-mortalize the beings that it shoots, the cinema find in sculpture a means to nurture its macabre labour. Besides, this display of death undergoes a very identifiable formal process : the inversion. We may then identify this plastic gesture with the metonymical figure of a burying. Thus, both cinema and sculpture seem to join in a funeral system of art.
263

Avaliação do ciclo de vida e pegada de carbono da reciclagem de CO2 em um sistema de produção de etanol de cana-de-açúcar / Life cycle assessment and carbon footprint of CO2 recycling in a sugarcane based ethanol production system

Funes, Rodrigo Hartkoff 02 March 2016 (has links)
A captura e uso do dióxido de carbono é uma das formas de ajudar a frear as emissões de gases do efeito estufa (GEE) e destiná-lo a um fim útil. Um possível uso para o CO2 seria como fertilizante agrícola, uma vez que as plantas quando em maiores concentrações deste gás ceteris paribus apresentam um incremento de biomassa. Os biocombustíveis são opções que contribuem para a mitigação das mudanças climáticas em detrimento ao uso de combustíveis fósseis e entre os biocombustíveis a produção de etanol a partir de cana-de-açúcar se destaca devido a vantagens quanto à emissão de GEE e energia acumulada. Essas vantagens podem ser ainda maiores com o uso do CO2 proveniente de suas biorrefinarias na forma de insumo agrícola. O objetivo deste trabalho é avaliar esta nova técnica de uso de carbono por meio da metodologia da Avaliação do Ciclo de Vida (ACV) e da pegada de carbono de produtos para encontrar suas contribuições no balanço de energia e carbono do sistema. Um modelo de dispersão de gases foi utilizado para saber se é possível manter a concentração de CO2 no campo dentro dos parâmetros necessários para o incremento de biomassa. A análise indica que um sistema adaptado de irrigação por gotejamento pode manter a concentração deste gás dentro do nível desejado quando a emissão fica em 22,5 g ha-1s-1, mas que uma mesma área não é autossuficiente para o fornecimento de CO2 para fase de crescimento dos colmos. Através da ACV e da pegada de carbono da cana-de-açúcar em um cenário onde o incremento de biomassa é médio em relação aos experimentos encontrados, a tecnologia reduz em 13,5% a demanda de energia e 11,8% as emissões de GEE por MJ de bioenergia produzida se comparada ao sistema tradicional. O balanço de energia para o sistema tradicional e com reciclagem de CO2 foi de 170 GJ/ha e 206 GJ/ha, enquanto o balanço de carbono foi de -13950 kgCO2eq/ha e -17019 kgCO2eq/ha, respectivamente. Considerando as possíveis variações de incremento de biomassa, para cada MJ produzido a emissão de GEE pode variar em 8,9% e o consumo de energia em 10,9%. Essa nova técnica de uso de carbono do ponto vista teórico pode ser aplicada em campo e implica em um aumento entre 13 a 30% do balanço de energia para um hectare de cana-de-açúcar, consequentemente uma menor quantidade de terra será necessária para atingir as metas energéticas estipuladas / Carbon capture and use (CCU) may slow down greenhouse gas (GHG) emissions and direct them to a useful end. A possible CO2 application is as plant fertilizer because ceteris paribus biomass increases when plants grow under high CO2 concentrations. Compared to fossil fuels, biofuels mitigate climate change, and the use of sugarcane ethanol stands out due to its low lifecycle GHG emissions and Cumulative Energy Demand (CED). Such benefits might be enhanced with the use of CO2 from the biorefinery as a crop fertilizer. The objective of this study is evaluating this new CCU scheme based on a life cycle assessment (LCA) and a carbon footprint to determine its energy and carbon balances. An air pollution dispersion model was used to verify whether it is possible to maintain the CO2 concentration on the field so that biomass increase takes place. The analysis demonstrates that a drip irrigation system can keep the concentration of gas within the desired level when the emission is 22.5 g ha-1s-1, but that the same area is not self sufficient to supply CO2 for the complete growth phase of the stalks. Results from the LCA and the carbon footprint demonstrate that compared to the traditional system, the scheme decreases CED and GHG emissions by 13,5% and 11,8%, respectively. The energy balance of the traditional and the recycling system were 170 GJ/ha and 206 GJ/ha, respectively, whereas the carbon balance was -13,950 kgCO2eq/ha and -17,019 kgCO2eq/ha, respectively. Considering the range of growth responses, for each MJ produced GHG emissions vary 8,9% whereas energy consumption varies 10,9%. These CCU scheme might be applied on the field and implies in improvements between 13 and 30% in the energy balance of 1ha of sugarcane; thus, a smaller land area will be needed than with the traditional system to achieve the energy goals
264

Metodologia para avaliação ambiental de bacias hidrográficas com uso de sistemas de suporte à decisão espacial e do indicador pegada ecológica / Methodology for envirnmental assessment of watersheds using spacial decision support systems and the ecological footprint.

Raul Rigoto Monteiro 20 August 2010 (has links)
No atual contexto ambiental é grande a demanda por informações consistentes que subsidiem o planejamento territorial, permitindo realizar avaliações ambientais e desta forma, subsidiar os setores público e privado. Essa demanda pode ser satisfeita com a integração de informações em um sistema, com propriedades e funções de processamento, possibilitando sua utilização em ambiente integrado. Assim, nesta dissertação é proposta uma metodologia para a avaliação ambiental de bacias hidrográficas que atua desde a escolha de indicadores e definição dos pesos de sua contribuição, até a execução de avaliações e espacialização de resultados em ambiente SIG. Esta metodologia é composta por duas fases distintas: avaliação da vulnerabilidade ambiental da bacia hidrográfica a partir do uso de sistemas de suporte à decisão espacial, e, avaliação da sustentabilidade da bacia através do cálculo do indicador Pegada Ecológica. Na primeira fase são adotados sistemas de suporte à decisão, bases de conhecimento, SIG e uma ferramenta que integra estes resultados permitindo a geração de avaliações, análises e/ou cenários prospectivos. Na segunda fase, a sustentabilidade da bacia é retratada a partir do cálculo da pegada ecológica que consiste na contabilização da área que uma população necessita para produzir os recursos consumidos e absorver os resíduos gerados. A comparação entre áreas mais vulneráveis e menos sustentáveis, pode nortear projetos de recuperação e conservação ambiental. / In the current environmental context is huge the demand for consistent information that supports the territorial planning, allowing environmental assessments thereby subsidizing public and private sectors. This demand can be satisfied with the integration of information into a system, with properties and processing functions, allowing its use in integrated environment. Thus, this thesis proposes a methodology for environmental assessment of watersheds that operates from the choice of indicators and definition of the weights of its contribution to the implementation of assessments and spatialisation of results in a GIS environment. This methodology is composed of two distinct phases: assessment of environmental vulnerability of the basin by the use of spatial decision support systems, and assessing the sustainability of the basin through the calculation of Ecological Footprint. In the first phase are adopted decision support systems, knowledge bases, GIS and a tool that integrates these results allowing the generation of assessments, analysis and / or prospective scenarios. In the second stage, the sustainability of the basin is pictured from the calculation of the ecological footprint, which consists in accounting the area that a population needs to produce the resources consumed and absorb the waste generated. The comparison between the most vulnerable and less sustainable, can guide restoration projects and environmental conservation.
265

Logistický řetězec květin / Logistics Chain of Flowers

Klusáková, Michaela January 2011 (has links)
This Diploma Thesis deals with the logistics chain of flowers and its individual components. The aim is to characterize the whole chain of flowers and to describe its components - from the grower to the retailer - and to suggest options for streamlining, mostly from the ecological perspective. The influence of different means of transport and heated greenhouses on the environment is evaluated through carbon footprint calculations. Part of the work is also devoted to the characteristics of the flower industry in the Czech Republic. The thesis came to the conclusion that the best is to transport flowers by ship, it is good for their quality and the less harmful for the environment. The second best choice is rail, also with very good quality of flowers and then the road and airplane, which is still less harmful to the environment than growing flowers in heated greenhouses.
266

Avaliação do ciclo de vida e pegada de carbono da reciclagem de CO2 em um sistema de produção de etanol de cana-de-açúcar / Life cycle assessment and carbon footprint of CO2 recycling in a sugarcane based ethanol production system

Rodrigo Hartkoff Funes 02 March 2016 (has links)
A captura e uso do dióxido de carbono é uma das formas de ajudar a frear as emissões de gases do efeito estufa (GEE) e destiná-lo a um fim útil. Um possível uso para o CO2 seria como fertilizante agrícola, uma vez que as plantas quando em maiores concentrações deste gás ceteris paribus apresentam um incremento de biomassa. Os biocombustíveis são opções que contribuem para a mitigação das mudanças climáticas em detrimento ao uso de combustíveis fósseis e entre os biocombustíveis a produção de etanol a partir de cana-de-açúcar se destaca devido a vantagens quanto à emissão de GEE e energia acumulada. Essas vantagens podem ser ainda maiores com o uso do CO2 proveniente de suas biorrefinarias na forma de insumo agrícola. O objetivo deste trabalho é avaliar esta nova técnica de uso de carbono por meio da metodologia da Avaliação do Ciclo de Vida (ACV) e da pegada de carbono de produtos para encontrar suas contribuições no balanço de energia e carbono do sistema. Um modelo de dispersão de gases foi utilizado para saber se é possível manter a concentração de CO2 no campo dentro dos parâmetros necessários para o incremento de biomassa. A análise indica que um sistema adaptado de irrigação por gotejamento pode manter a concentração deste gás dentro do nível desejado quando a emissão fica em 22,5 g ha-1s-1, mas que uma mesma área não é autossuficiente para o fornecimento de CO2 para fase de crescimento dos colmos. Através da ACV e da pegada de carbono da cana-de-açúcar em um cenário onde o incremento de biomassa é médio em relação aos experimentos encontrados, a tecnologia reduz em 13,5% a demanda de energia e 11,8% as emissões de GEE por MJ de bioenergia produzida se comparada ao sistema tradicional. O balanço de energia para o sistema tradicional e com reciclagem de CO2 foi de 170 GJ/ha e 206 GJ/ha, enquanto o balanço de carbono foi de -13950 kgCO2eq/ha e -17019 kgCO2eq/ha, respectivamente. Considerando as possíveis variações de incremento de biomassa, para cada MJ produzido a emissão de GEE pode variar em 8,9% e o consumo de energia em 10,9%. Essa nova técnica de uso de carbono do ponto vista teórico pode ser aplicada em campo e implica em um aumento entre 13 a 30% do balanço de energia para um hectare de cana-de-açúcar, consequentemente uma menor quantidade de terra será necessária para atingir as metas energéticas estipuladas / Carbon capture and use (CCU) may slow down greenhouse gas (GHG) emissions and direct them to a useful end. A possible CO2 application is as plant fertilizer because ceteris paribus biomass increases when plants grow under high CO2 concentrations. Compared to fossil fuels, biofuels mitigate climate change, and the use of sugarcane ethanol stands out due to its low lifecycle GHG emissions and Cumulative Energy Demand (CED). Such benefits might be enhanced with the use of CO2 from the biorefinery as a crop fertilizer. The objective of this study is evaluating this new CCU scheme based on a life cycle assessment (LCA) and a carbon footprint to determine its energy and carbon balances. An air pollution dispersion model was used to verify whether it is possible to maintain the CO2 concentration on the field so that biomass increase takes place. The analysis demonstrates that a drip irrigation system can keep the concentration of gas within the desired level when the emission is 22.5 g ha-1s-1, but that the same area is not self sufficient to supply CO2 for the complete growth phase of the stalks. Results from the LCA and the carbon footprint demonstrate that compared to the traditional system, the scheme decreases CED and GHG emissions by 13,5% and 11,8%, respectively. The energy balance of the traditional and the recycling system were 170 GJ/ha and 206 GJ/ha, respectively, whereas the carbon balance was -13,950 kgCO2eq/ha and -17,019 kgCO2eq/ha, respectively. Considering the range of growth responses, for each MJ produced GHG emissions vary 8,9% whereas energy consumption varies 10,9%. These CCU scheme might be applied on the field and implies in improvements between 13 and 30% in the energy balance of 1ha of sugarcane; thus, a smaller land area will be needed than with the traditional system to achieve the energy goals
267

Lobbing - ekonomické a právní aspekty : Postoje členů akademické právnické obce a zákonodárného sboru dolní komory Parlamentu České republiky k regulaci lobbingu / Lobbying - economic and legal aspects : attitudes of members of the law academia and members of the lower house of the Parliament of the Czech Republic to the regulation of lobbying

Blažek, Matej January 2018 (has links)
Lobbying - Economic and Legal aspects Abstract The diploma thesis deals with lobbying and its economic and legal aspects. The aim of the thesis is to present lobbying from a broad perspective in the context of other regulations by using descriptive, comparative and analytical methods and to provide a comprehensive overview of the development of efforts to regulate lobbying in the Czech Republic. Particular attention is paid to the analysis of the last governmental regulatory initiative where I am testing a hypothesis of whether the underway regulation is systemically correct in light of examples in other countries. I also conducted two surveys aimed at finding out the attitudes of members of the law academia and members of the lower house of the Parliament of the Czech Republic to the regulation of lobbying in the Czech Republic. The data serve both to (i) illustrate the interpretation of lobbying across the work, (ii) but also because of the specific proposed variant of lobbying within the framework of the approved substantive intent of the lobbying law (the deadline for submitting a paragraph to the government is set to end 2018), and (iii) I believe that they can be useful even when finalizing the bill, or other later proposed measures under the de lege ferenda considerations on lobbying. The thesis is...
268

Mapping the environmental footprint of the Central Plains Water irrigation scheme : a thesis submitted in partial fulfilment of the Masters of Design at the Institute of Communication Design, Massey University, Wellington, NZ

Ivamy, Dean January 2009 (has links)
In the statement Mayor Parker is referring to a complexity of issues that involves a plethora of hard-scientific and statistical information. The diversity of opinions regarding the scheme’s benefits and potential negative implications also create misunderstanding for the general public. This prompts the hypothesis of this design thesis, which suggests that statistical data when visually mapped and in the context of its physical environment can provide significant cognitive and ecological awareness for the viewer to understand the economic and environmental implications of the proposed irrigation scheme. Both the areas of cartographic mapping and the dairy industry contain controlled vocabularies, which present opportunity for graphic modeling and explanation through visible phenomena. The Canterbury Plains has a well-established historical and agricultural narrative. However, due to the recent dramatic and substantial transition of the region’s dairy industry between the periods 1995 – 2008, subsequent demand for freshwater now represents the real prospect of uncharted future environmental instability. The development of a visual language system capable of the interpretation and construction of the irrigation scheme’s benefits and potential negative implications, provide this thesis through graphic modeling the possibility to compare the proposed CPW scheme’s issues. While some industry groups consider public participation as arbitrary and unnecessary, recent surveys indicate water quality and fertiliser management as the most significant areas for environmental concern. The debate should not exclude the public, but rather include communication systems capable of reaching all communities.
269

Development of a calculator for estimation and management of GHG emissions from public transit agency operations

Weigel, Brent Anthony 08 July 2010 (has links)
As managers of extensive vehicle fleets and transportation infrastructures, public transit agencies present unique opportunities for reducing greenhouse gas (GHG) emissions from the transportation sector. To achieve substantial and cost-effective GHG emissions reductions from their activities, public transit agencies need tools and resources that enable effective GHG emissions management. This research thesis presents the background, methodology, and results of the author's development of a public transit agency-level life cycle GHG emissions calculator. The development of the calculator involved a series of research efforts aimed at identifying and addressing the needs of transit agency GHG emissions management: a review of background information on climate change and public transit's role in mitigating climate change; a review of existing GHG emissions calculators for public transit agencies, a review of the methodologies for life cycle GHG emissions analysis; integration and adaption of existing calculation resources; development of calculator spreadsheets for estimating relevant lifecycle GHG emissions and quantifying GHG emission reduction cost-effectiveness; application of the developed calculator to a carbon footprint analysis for a typical mid-size to large-size transit agency; and application of the developed calculator to the evaluation of the cost-effectiveness of various potential strategies for reducing transit agency GHG emissions. The developed calculator provides an integrative resource for quantifying GHG emissions and costs of public transit agency activities, including GHG emission reduction strategies. Further research is needed to calibrate the estimation of upstream life cycle GHG emissions, particularly for vehicle manufacture and maintenance.
270

Transportation energy and carbon footprints for U.S. corridors

Sonnenberg, Anthony H. 10 November 2010 (has links)
Changes in climate caused by changes in anthropogenic (i.e. "man-made") greenhouse gas (GHG) emissions have become a major public policy issue in countries all over the world. With an estimated 28.4% of these emissions attributed to the transportation sector, attention is being focused on strategies aimed at reducing transportation GHG emissions. Quantifying the change in GHG emissions due to such strategies is one of the most challenging aspects of integrating GHG emissions and climate change into transportation planning and policy analysis; the inventory techniques and methods for estimating the impact of different strategies and policies are still relatively unsophisticated. This research developed a method for estimating intercity passenger transportation energy and carbon footprints and applied this method to three US DOT-designated high speed rail (HSR) corridors in the U.S.-- San Francisco/Los Angeles/San Diego; Seattle/Portland/Eugene, and Philadelphia/Harrisburg/Pittsburg. The methodology consists of estimating the number of trips by mode, estimating the direct CO₂ emissions, and estimating indirect CO₂ emissions. For each study corridor the impacts of different strategies and policies on carbon dioxide emissions were estimated as an illustration of the policy application of the developed methodology. The largest gain in CO₂ savings can be achieved by strategies aiming at automobile emissions, due to its sizeable share as main mode and access/egress mode to and from airports and bus and train stations: an average fuel economy of 35.5 mpg would result in a 38-42% savings of total CO₂ emissions; replacing 25% of gasoline use with cellulosic ethanol can have a positive impact on CO₂ emissions of about 13.4-14.5%; and a 10% market share for electric vehicles would result in potential CO₂ savings of 3.4-7.8%. The impact of a 20% or 35% improvement in aircraft efficiency on CO₂ savings is much lower (0.88-3.65%) than the potential impacts of the policies targeting automobile emissions. Three HSR options were analyzed using Volpe's long-distance demand model: HSR125, HSR150, and HSR200. Only the HSR150 and HSR200 would result in CO₂ savings, and then just for two of the three corridors: the Pacific Northwest (1.5%) and California (0.8-0.9%). With increased frequency and load factors, a HSR150 system could result in CO₂ savings of 5.2% and 1.8% for the Pacific Northwest and California, respectively. This would require a mode shift from auto of 5-6%. This shift in auto mode share would mainly have to be a result of pricing strategies. From these results, HSR may not be such an obvious choice, however, with increased ridership and diversions from other modes, CO₂ savings increase significantly due to the lower emissions per passenger mile for HSR. The framework developed in this study has the ability to determine the GHG emissions for such HSR options and increased diversions.

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