828 resultados para emissions policies
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Decades of research show that environmental exposure to the chemical benzene is associated with severe carcinogenic, hematoxic and genotoxic effects on the human body. As such, the Environmental Protection Agency (EPA) has designated the chemical as a Hazardous Air Pollutant and prescribed benzene air concentration guidelines that provide cities with an ideal ambient level to protect human health. However, in Houston, Texas, a city home to the top industrial benzene emitters in the US who undoubtedly contribute greatly to the potentially unsafe levels of ambient benzene, regulations beyond the EPA’s unenforceable guidelines are critical to protecting public health. Despite this, the EPA has failed to establish National Ambient Air Quality Standards (NAAQS) for benzene. States are thus left to regulate air benzene levels on their own; in the case of Texas, the Texas Commission on Environmental Quality (TCEQ) and state legislature have failed to proactively develop legally enforceable policies to reduce major source benzene emissions. This inaction continues to exacerbate a public health problem, which may only be solved through a legal framework that restricts preventable benzene emissions to protect human health and holds industrial companies accountable for violations of such regulations and standards. This analysis explores legal barriers that the City of Houston and other relevant agencies currently face in their attempt to demand and bring about such change. ^
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To tackle global climate change, it is desirable to reduce CO2 emissions associated with household consumption in particular in developed countries, which tend to have much higher per capita household carbon footprints than less developed countries. Our results show that carbon intensity of different consumption categories in the U.S. varies significantly. The carbon footprint tends to increase with increasing income but at a decreasing rate due to additional income being spent on less carbon intensive consumption items. This general tendency is frequently compensated by higher frequency of international trips and higher housing related carbon emissions (larger houses and more space for consumption items). Our results also show that more than 30% of CO2 emissions associated with household consumption in the U.S. occur outside of the U.S. Given these facts, the design of carbon mitigation policies should take changing household consumption patterns and international trade into account.
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streets in local residential areas in large cities, real traffic tests for pollutant emissions and fuel consumption have been carried out in Madrid city centre. Emission concentration and car activity were simultaneously measured by a Portable Emissions Measurement System. Real life tests carried out at different times and on different days were performed with a turbo-diesel engine light vehicle equipped with an oxidizer catalyst and using different driving styles with a previously trained driver. The results show that by reducing the speed limit from 50 km h-1 to 30 km h-1, using a normal driving style, the time taken for a given trip does not increase, but fuel consumption and NOx, CO and PM emissions are clearly reduced. Therefore, the main conclusion of this work is that reducing the speed limit in some narrow streets in residential and commercial areas or in a city not only increases pedestrian safety, but also contributes to reducing the environmental impact of motor vehicles and reducing fuel consumption. In addition, there is also a reduction in the greenhouse gas emissions resulting from the combustion of the fuel.
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The European energy sector is undergoing a major transformation and is facing a series of difficult challenges. These include a high and increasing dependence on external energy resources; dramatically reduce the need for the emissions of greenhouse gases to meet environmental objectives and the difficulties related to the promotion of energy market effectively integrated and competitive. Some of the policies associated with the various objectives are sometimes in conflict with each other, while in other cases are mutually reinforcing.The aim of this paper is to do a scienti?c analysis of the developments so far and the expectations for the coming period focusing on the pillars of energy policy in the EU in terms of security of supply, environment, climate change and promoting a competitive and integrated market. The use of renewable energy sources is seen as a key element of European energy policy and should help to: reduce dependence on fuel from non-member countries; reduce emissions from carbon-based energy sources, and; decouple energy costs from oil prices.
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El objetivo de esta investigación es desarrollar una metodología para estimar los potenciales impactos económicos y de transporte generados por la aplicación de políticas en el sector transporte. Los departamentos de transporte y otras instituciones gubernamentales relacionadas se encuentran interesadas en estos análisis debido a que son presentados comúnmente de forma errónea por la insuficiencia de datos o por la falta de metodologías adecuadas. La presente investigación tiene por objeto llenar este vacío haciendo un análisis exhaustivo de las técnicas disponibles que coincidan con ese propósito. Se ha realizado un análisis que ha identificado las diferencias cuando son aplicados para la valoración de los beneficios para el usuario o para otros efectos como aspectos sociales. Como resultado de ello, esta investigación ofrece un enfoque integrado que incluye un modelo Input-Output de múltiples regiones basado en la utilidad aleatoria (RUBMRIO), y un modelo de red de transporte por carretera. Este modelo permite la reproducción con mayor detalle y realismo del transporte de mercancías que por medio de su estructura sectorial identifica los vínculos de las compras y ventas inter-industriales dentro de un país utilizando los servicios del transporte de mercancías. Por esta razón, el modelo integrado es aplicable a diversas políticas de transporte. En efecto, el enfoque se ha aplicado para estudiar los efectos macroeconómicos regionales de la implementación de dos políticas diferentes en el sistema de transporte de mercancías de España, tales como la tarificación basada en la distancia recorrida por vehículo-kilómetro (€/km) aplicada a los vehículos del transporte de mercancías, y para la introducción de vehículos más largos y pesados de mercancías en la red de carreteras de España. El enfoque metodológico se ha evaluado caso por caso teniendo en cuenta una selección de la red de carreteras que unen las capitales de las regiones españolas. También se ha tenido en cuenta una dimensión económica a través de una tabla Input-Output de múltiples regiones (MRIO) y la base de datos de conteo de tráfico existente para realizar la validación del modelo. El enfoque integrado reproduce las condiciones de comercio observadas entre las regiones usando el sistema de transporte de mercancías por carretera, y que permite por comparación con los escenarios de políticas, determinar las contribuciones a los cambios distributivos y generativos. Así pues, el análisis estima los impactos económicos en cualquier región considerando los cambios en el Producto Interno Bruto (PIB) y el empleo. El enfoque identifica los cambios en el sistema de transporte a través de todos los caminos de la red de transporte a través de las medidas de efectividad (MOEs). Los resultados presentados en esta investigación proporcionan evidencia sustancial de que en la evaluación de las políticas de transporte, es necesario establecer un vínculo entre la estructura económica de las regiones y de los servicios de transporte. Los análisis muestran que para la mayoría de las regiones del país, los cambios son evidentes para el PIB y el empleo, ya que el comercio se fomenta o se inhibe. El enfoque muestra cómo el tráfico se desvía en ambas políticas, y también determina detalles de las emisiones de contaminantes en los dos escenarios. Además, las políticas de fijación de precios o de regulación de los sistemas de transporte de mercancías por carretera dirigidas a los productores y consumidores en las regiones promoverán transformaciones regionales afectando todo el país, y esto conduce a conclusiones diferentes. Así mismo, este enfoque integrado podría ser útil para evaluar otras políticas y otros países en todo el mundo. The purpose of this research is to develop a methodological approach aimed at assessing the potential economic and transportation impacts of transport policies. Transportation departments and other related government parties are interested in such analysis because it is commonly misrepresented for the insufficiency of data and suitable methodologies available. This research is directed at filling this gap by making a comprehensive analysis of the available techniques that match with that purpose. The differences when they are applied for the valuation of user benefits or for other impacts as social matters have been identified. As a result, this research presents an integrated approach which includes both a random utility-based multiregional Input-Output model (RUBMRIO), and a road transport network model. This model accounts for freight transport with more detail and realism because its commodity-based structure traces the linkages of inter-industry purchases and sales that use freight services within a given country. For this reason, the integrated model is applicable to various transport policies. In fact, the approach is applied to study the regional macroeconomic effects of implementing two different policies in the freight transport system of Spain, such as a distance-based charge in vehicle-kilometer (€/km) for Heavy Goods Vehicles (HGVs), and the introduction of Longer and Heavier Vehicles (LHVs) in the road network of Spain. The methodological approach has been evaluated on a case by case basis considering a selected road network of highways linking the capitals of the Spanish regions. It has also considered an economic dimension through a Multiregional Input Output Table (MRIO) and the existing traffic count database used in the model validation. The integrated approach replicates observed conditions of trade among regions using road freight transport systems that determine contributions to distributional and generative changes by comparison with policy scenarios. Therefore, the model estimates economic impacts in any given area by considering changes in Gross Domestic Product (GDP), employment (jobs), and in the transportation system across all paths of the transport network considering Measures of effectiveness (MOEs). The results presented in this research provide substantive evidence that in the assessment of transport policies it is necessary to establish a link between the economic structure of regions and the transportation services. The analysis shows that for most regions in the country, GDP and employment changes are noticeable when trade is encouraged or discouraged. This approach shows how traffic is diverted in both policies, and also provides details of the pollutant emissions in both scenarios. Furthermore, policies, such as pricing or regulation of road freight transportation systems, directed to producers and consumers in regions will promote different regional transformations across the country, and this lead to different conclusions. In addition, this integrated approach could be useful to assess other policies and countries worldwide.
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Road traffic is the greatest contributor to the carbon footprint of the transport sector and reducing it has become one of the main targets of sustainable transport policies. An analysis of the main factors influencing greenhouse gas (GHG) emissions is essential for designing new energy- and environmentally efficient strategies for the road transport. This paper addresses this need by (i) identifying factors which influence the carbon footprint, including traffic activity, fuel economy and socioeconomic development; and (ii) proposing a methodological framework which uses Modified Laspeyres Index decomposition to analyze the effect of important drivers on the changes in emissions of road transport in Spain during the period from 1990 to 2010. The results demonstrate that the country׳s economic growth has been closely linked to the rise in GHG emissions. The innovative contribution of this paper is the special analysis of the changes in mobility patterns and GHG emissions during the economic crisis, when, for the first time, Spanish road traffic emissions decreased. The reduction of road transport and improved energy efficiency has been powerful contributors to this decrease, demonstrating the effectiveness of energy-saving measures. On the basis of this analysis, several tailored policy recommendations have been suggested for future implementation.
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Esta Tesis surgió ante la intensidad y verosimilitud de varias señales o “warnings” asociadas a políticas dirigidas a reducir el peso del petróleo en el sector energético, tanto por razones económicas, como geopolíticas, como ambientales. Como tal Tesis se consolidó al ir incorporando elementos novedosos pero esenciales en el mundo petrolífero, particularmente las “tecnologías habilitantes”, tanto de incidencia directa, como el “fracking” como indirecta, del cual es un gran ejemplo el Vehículo Eléctrico (puro). La Tesis se definió y estructuró para elaborar una serie de indagaciones y disquisiciones, que comportaran un conjunto de conclusiones que fueran útiles para las corporaciones energéticas. También para la comprensión de la propia evolución del sector y de sus prestaciones técnicas y económicas, de cara a dar el servicio que los usuarios finales piden. Dentro de las tareas analíticas y reflexivas de la Tesis, se acuñaron ciertos términos conceptuales para explicar más certeramente la realidad del sector, y tal es el caso del “Investment burden”, que pondera la inversión específica (€/W) requerida por una instalación, con la duración del período de construcción y los riesgos tanto tangibles como regulatorios. Junto a ello la Tesis propone una herramienta de estudio y prognosis, denominada “Market integrated energy efficiency”, especialmente aplicable a dicotomías. Tal es el caso del coche térmico, versus coche eléctrico. El objetivo es optimizar una determinada actividad energética, o la productividad total del sector. Esta Tesis propone varias innovaciones, que se pueden agrupar en dos niveles: el primero dentro del campo de la Energía, y el segundo dentro del campo de las corporaciones, y de manera especial de las corporaciones del sector hidrocarburos. A nivel corporativo, la adaptación a la nueva realidad será función directa de la capacidad de cada corporación para desarrollar y/o comprar las tecnologías que permitan mantener o aumentar cuota de mercado. Las conclusiones de la Tesis apuntan a tres opciones principalmente para un replanteamiento corporativo: - Diversificación energética - Desplazamiento geográfico - Beneficiándose de posibles nuevos nichos tecnológicos, como son: • En upstream: Recuperación estimulada de petróleo mediante uso de energías renovables • En downstream: Aditivos orientados a reducir emisiones • En gestión del cambio: Almacenamiento energético con fines operativos Algunas políticas energéticas siguen la tendencia de crecimiento cero de algunos países de la OCDE. No obstante, la realidad mundial es muy diferente a la de esos países. Por ejemplo, según diversas estimaciones (basadas en bancos de datos solventes, referenciados en la Tesis) el número de vehículos aumentará desde aproximadamente mil millones en la actualidad hasta el doble en 2035; mientras que la producción de petróleo sólo aumentará de 95 a 145 millones de barriles al día. Un aumento del 50% frente a un aumento del 100%. Esto generará un curioso desajuste, que se empezará a sentir en unos pocos años. Las empresas y corporaciones del sector hidrocarburos pueden perder el monopolio que atesoran actualmente en el sector transporte frente a todas las demás fuentes energéticas. Esa pérdida puede quedar compensada por una mejor gestión de todas sus capacidades y una participación más integrada en el mundo de la energía, buscando sinergias donde hasta ahora no había sino distanciamiento. Los productos petrolíferos pueden alimentar cualquier tipo de maquina térmica, como las turbinas Brayton, o alimentar reformadores para la producción masiva de H2 para su posterior uso en pilas combustible. El almacenamiento de productos derivados del petróleo no es ningún reto ni plantea problema alguno; y sin embargo este almacenamiento es la llave para resolver muchos problemas. Es posible que el comercio de petróleo se haga menos volátil debido a los efectos asociados al almacenamiento; pero lo que es seguro es que la eficiencia energética de los usos de ese petróleo será más elevada. La Tesis partía de ciertas amenazas sobre el futuro del petróleo, pero tras el análisis realizado se puede vislumbrar un futuro prometedor en la fusión de políticas medioambientales coercitivas y las nuevas tecnologías emergentes del actual portafolio de oportunidades técnicas. ABSTRACT This Thesis rises from the force and the credibility of a number of warning signs linked to policies aimed at reducing the role of petroleum in the energy industry due to economical, geopolitical and environmental drives. As such Thesis, it grew up based on aggregating new but essentials elements into the petroleum sector. This is the case of “enabling technologies” that have a direct impact on the petroleum industry (such as fracking), or an indirect but deep impact (such as the full electrical vehicle). The Thesis was defined and structured in such a way that could convey useful conclusions for energy corporations through a series of inquiries and treatises. In addition to this, the Thesis also aims at understating la evolution of the energy industry and its capabilities both technical and economical, towards delivering the services required by end users. Within the analytical task performed in the Thesis, new terms were coined. They depict concepts that aid at explaining the facts of the energy industry. This is the case for “Investment burden”, it weights the specific capital investment (€/W) required to build a facility with the time that takes to build it, as well as other tangible risks as those posed by regulation. In addition to this, the Thesis puts forward an application designed for reviewing and predicting: the so called “Market integrated energy efficiency”, especially well-suited for dichotomies, very appealing for the case of the thermal car versus the electric car. The aim is to optimize energy related activity; or even the overall productivity of the system. The innovations proposed in this Thesis can be classified in two tiers. Tier one, within the energy sector; and tier two, related to Energy Corporation in general, but with oil and gas corporations at heart. From a corporate level, the adaptation to new energy era will be linked with the corporation capability to develop or acquire those technologies that will yield to retaining or enhancing market share. The Thesis highlights three options for corporate evolution: - diversification within Energy - geographic displacement - profiting new technologies relevant to important niches of work for the future, as: o Upstream: enhanced oil recovery using renewable energy sources (for upstream companies in the petroleum business) o Downstream: additives for reducing combustion emissions o Management of Change: operational energy storage Some energy policies tend to follow the zero-growth of some OECD countries, but the real thing could be very different. For instance, and according to estimates the number of vehicles in use will grow from 1 billion to more than double this figure 2035; but oil production will only grow from 95 million barrel/day to 145 (a 50% rise of versus an intensification of over a 100%). Hydrocarbon Corporation can lose the monopoly they currently hold over the supply of energy to transportation. This lose can be mitigated through an enhanced used of their capabilities and a higher degree of integration in the world of energy, exploring for synergies in those places were gaps were present. Petroleum products can be used to feed any type of thermal machine, as Brayton turbines, or steam reformers to produce H2 to be exploited in fuel cells. Storing petroleum products does not present any problem, but very many problems can be solved with them. Petroleum trading will likely be less volatile because of the smoothing effects of distributed storage, and indeed the efficiency in petroleum consumption will be much higher. The Thesis kicked off with a menace on the future of petroleum. However, at the end of the analysis, a bright future can be foreseen in the merging between highly demanding environmental policies and the relevant technologies of the currently emerging technical portfolio.
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Acknowledgements The authors thank the Global Research Alliance on Agricultural Greenhouse Gases for facilitating this work. The contribution of P.S. contributed to the EU-funded GHG Europe project.
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This BEEP explains the mechanism of the EU Emissions Trading System (ETS) for the greenhouse gas carbon dioxide and explore into its likely sustainability impact on European industry. In doing so, it focuses on energy-intensive industries like cement, steel and aluminium production as well as on the emerging hydrogen economy. The BEEP concludes that at the moment it is still very inconsistently implemented and has a fairly narrow scope regarding greenhouse gases and involved sectors. It may also give an incentive to relocate for energy-intensive industries. In its current format, the EU ETS does not yet properly facilitate long term innovation dynamics such as the transition to a hydrogen economy. Nevertheless, the EU ETS is foremost a working system that – with some improvements – has the potential to become a pillar for effective and efficient climate change policy that also gives incentives for investment into climate friendly policies.
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Recent attention has focused on the high rates of annual carbon sequestration in vegetated coastal ecosystems—marshes, mangroves, and seagrasses—that may be lost with habitat destruction (‘conversion’). Relatively unappreciated, however, is that conversion of these coastal ecosystems also impacts very large pools of previously-sequestered carbon. Residing mostly in sediments, this ‘blue carbon’ can be released to the atmosphere when these ecosystems are converted or degraded. Here we provide the first global estimates of this impact and evaluate its economic implications. Combining the best available data on global area, land-use conversion rates, and near-surface carbon stocks in each of the three ecosystems, using an uncertainty-propagation approach, we estimate that 0.15–1.02 Pg (billion tons) of carbon dioxide are being released annually, several times higher than previous estimates that account only for lost sequestration. These emissions are equivalent to 3–19% of those from deforestation globally, and result in economic damages of $US 6–42 billion annually. The largest sources of uncertainty in these estimates stems from limited certitude in global area and rates of land-use conversion, but research is also needed on the fates of ecosystem carbon upon conversion. Currently, carbon emissions from the conversion of vegetated coastal ecosystems are not included in emissions accounting or carbon market protocols, but this analysis suggests they may be disproportionally important to both. Although the relevant science supporting these initial estimates will need to be refined in coming years, it is clear that policies encouraging the sustainable management of coastal ecosystems could significantly reduce carbon emissions from the land-use sector, in addition to sustaining the well-recognized ecosystem services of coastal habitats.
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Globally, efforts are underway to reduce anthropogenic greenhouse gas emissions and to adapt to climate change impacts at the local level. However, there is a poor understanding of the relationship between city strategies on climate change mitigation and adaptation and the relevant policies at national and European level. This paper describes a comparative study and evaluation of cross-national policy. It reports the findings of studying the climate change strategies or plans from 200 European cities from Austria, Belgium, Estonia, Finland, France, Germany, Ireland, Italy, Netherlands, Spain and the United Kingdom. The study highlights the shared responsibility of global, European, national, regional and city policies. An interpretation and illustration of the influences from international and national networks and policy makers in stimulating the development of local strategies and actions is proposed. It was found that there is no archetypical way of planning for climate change, and multiple interests and motivations are inevitable. Our research warrants the need for a multi-scale approach to climate policy in the future, mainly ensuring sufficient capacity and resource to enable local authorities to plan and respond to their specific climate change agenda for maximising the management potentials for translating environmental challenges into opportunities.
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Landnutzungsänderungen sind eine wesentliche Ursache von Treibhausgasemissionen. Die Umwandlung von Ökosystemen mit permanenter natürlicher Vegetation hin zu Ackerbau mit zeitweise vegetationslosem Boden (z.B. nach der Bodenbearbeitung vor der Aussaat) führt häufig zu gesteigerten Treibhausgasemissionen und verminderter Kohlenstoffbindung. Weltweit dehnt sich Ackerbau sowohl in kleinbäuerlichen als auch in agro-industriellen Systemen aus, häufig in benachbarte semiaride bis subhumide Rangeland Ökosysteme. Die vorliegende Arbeit untersucht Trends der Landnutzungsänderung im Borana Rangeland Südäthiopiens. Bevölkerungswachstum, Landprivatisierung und damit einhergehende Einzäunung, veränderte Landnutzungspolitik und zunehmende Klimavariabilität führen zu raschen Veränderungen der traditionell auf Tierhaltung basierten, pastoralen Systeme. Mittels einer Literaturanalyse von Fallstudien in ostafrikanischen Rangelands wurde im Rahmen dieser Studie ein schematisches Modell der Zusammenhänge von Landnutzung, Treibhausgasemissionen und Kohlenstofffixierung entwickelt. Anhand von Satellitendaten und Daten aus Haushaltsbefragungen wurden Art und Umfang von Landnutzungsänderungen und Vegetationsveränderungen an fünf Untersuchungsstandorten (Darito/Yabelo Distrikt, Soda, Samaro, Haralo, Did Mega/alle Dire Distrikt) zwischen 1985 und 2011 analysiert. In Darito dehnte sich die Ackerbaufläche um 12% aus, überwiegend auf Kosten von Buschland. An den übrigen Standorten blieb die Ackerbaufläche relativ konstant, jedoch nahm Graslandvegetation um zwischen 16 und 28% zu, während Buschland um zwischen 23 und 31% abnahm. Lediglich am Standort Haralo nahm auch „bare land“, vegetationslose Flächen, um 13% zu. Faktoren, die zur Ausdehnung des Ackerbaus führen, wurden am Standort Darito detaillierter untersucht. GPS Daten und anbaugeschichtlichen Daten von 108 Feldern auf 54 Betrieben wurden in einem Geographischen Informationssystem (GIS) mit thematischen Boden-, Niederschlags-, und Hangneigungskarten sowie einem Digitales Höhenmodell überlagert. Multiple lineare Regression ermittelte Hangneigung und geographische Höhe als signifikante Erklärungsvariablen für die Ausdehnung von Ackerbau in niedrigere Lagen. Bodenart, Entfernung zum saisonalen Flusslauf und Niederschlag waren hingegen nicht signifikant. Das niedrige Bestimmtheitsmaß (R²=0,154) weist darauf hin, dass es weitere, hier nicht erfasste Erklärungsvariablen für die Richtung der räumlichen Ausweitung von Ackerland gibt. Streudiagramme zu Ackergröße und Anbaujahren in Relation zu geographischer Höhe zeigen seit dem Jahr 2000 eine Ausdehnung des Ackerbaus in Lagen unter 1620 müNN und eine Zunahme der Schlaggröße (>3ha). Die Analyse der phänologischen Entwicklung von Feldfrüchten im Jahresverlauf in Kombination mit Niederschlagsdaten und normalized difference vegetation index (NDVI) Zeitreihendaten dienten dazu, Zeitpunkte besonders hoher (Begrünung vor der Ernte) oder niedriger (nach der Bodenbearbeitung) Pflanzenbiomasse auf Ackerland zu identifizieren, um Ackerland und seine Ausdehnung von anderen Vegetationsformen fernerkundlich unterscheiden zu können. Anhand der NDVI Spektralprofile konnte Ackerland gut Wald, jedoch weniger gut von Gras- und Buschland unterschieden werden. Die geringe Auflösung (250m) der Moderate Resolution Imaging Spectroradiometer (MODIS) NDVI Daten führte zu einem Mixed Pixel Effect, d.h. die Fläche eines Pixels beinhaltete häufig verschiedene Vegetationsformen in unterschiedlichen Anteilen, was deren Unterscheidung beeinträchtigte. Für die Entwicklung eines Echtzeit Monitoring Systems für die Ausdehnung des Ackerbaus wären höher auflösende NDVI Daten (z.B. Multispektralband, Hyperion EO-1 Sensor) notwendig, um kleinräumig eine bessere Differenzierung von Ackerland und natürlicher Rangeland-Vegetation zu erhalten. Die Entwicklung und der Einsatz solcher Methoden als Entscheidungshilfen für Land- und Ressourcennutzungsplanung könnte dazu beitragen, Produktions- und Entwicklungsziele der Borana Landnutzer mit nationalen Anstrengungen zur Eindämmung des Klimawandels durch Steigerung der Kohlenstofffixierung in Rangelands in Einklang zu bringen.
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Thesis (Master's)--University of Washington, 2016-06
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Surface ozone is formed in the presence of NOx (NO + NO2) and volatile organic compounds (VOCs) and is hazardous to human health. A better understanding of these precursors is needed for developing effective policies to improve air quality. To evaluate the year-to-year changes in source contributions to total VOCs, Positive Matrix Factorization (PMF) was used to perform source apportionment using available hourly observations from June through August at a Photochemical Assessment Monitoring Station (PAMS) in Essex, MD for each year from 2007-2015. Results suggest that while gasoline and vehicle exhaust emissions have fallen, the contribution of natural gas sources to total VOCs has risen. To investigate this increasing natural gas influence, ethane measurements from PAMS sites in Essex, MD and Washington, D.C. were examined. Following a period of decline, daytime ethane concentrations have increased significantly after 2009. This trend appears to be linked with the rapid shale gas production in upwind, neighboring states, especially Pennsylvania and West Virginia. Back-trajectory analyses similarly show that ethane concentrations at these monitors were significantly greater if air parcels had passed through counties containing a high density of unconventional natural gas wells. In addition to VOC emissions, the compressors and engines involved with hydraulic fracturing operations also emit NOx and particulate matter (PM). The Community Multi-scale Air Quality (CMAQ) Model was used to simulate air quality for the Eastern U.S. in 2020, including emissions from shale gas operations in the Appalachian Basin. Predicted concentrations of ozone and PM show the largest decreases when these natural gas resources are hypothetically used to convert coal-fired power plants, despite the increased emissions from hydraulic fracturing operations expanded into all possible shale regions in the Appalachian Basin. While not as clean as burning natural gas, emissions of NOx from coal-fired power plants can be reduced by utilizing post-combustion controls. However, even though capital investment has already been made, these controls are not always operated at optimal rates. CMAQ simulations for the Eastern U.S. in 2018 show ozone concentrations decrease by ~5 ppb when controls on coal-fired power plants limit NOx emissions to historically best rates.
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Although mitigating GHG emissions is necessary to reduce the overall negative climate change impacts on crop yields and agricultural production, certain mitigation measures may generate unintended consequences to food availability and access due to land use competition and economic burden of mitigation. Prior studies have examined the co-impacts on food availability and global producer prices caused by alternative climate policies. More recent studies have looked at the reduction in total caloric intake driven by both changing income and changing food prices under one specific climate policy. However, due to inelastic calorie demand, consumers’ well-being are likely further reduced by increased food expenditures. Built upon existing literature, my dissertation explores how alternative climate policy designs might adversely affect both caloric intake and staple food budget share to 2050, by using the Global Change Assessment Model (GCAM) and a post-estimated metric of food availability and access (FAA). My dissertation first develop a set of new metrics and methods to explore new perspectives of food availability and access under new conditions. The FAA metric consists of two components, the fraction of GDP per capita spent on five categories of staple food and total caloric intake relative to a reference level. By testing the metric against alternate expectations of the future, it shows consistent results with previous studies that economic growth dominates the improvement of FAA. As we increase our ambition to achieve stringent climate targets, two policy conditions tend to have large impacts on FAA driven by competing land use and increasing food prices. Strict conservation policies leave the competition between bioenergy and agriculture production on existing commercial land, while pricing terrestrial carbon encourages large-scale afforestation. To avoid unintended outcomes to food availability and access for the poor, pricing land emissions in frontier forests has the advantage of selecting more productive land for agricultural activities compared to the full conservation approach, but the land carbon price should not be linked to the price of energy system emissions. These results are highly relevant to effective policy-making to reduce land use change emissions, such as the Reduced Emissions from Deforestation and Forest Degradation (REDD).