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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.
11

Investigation Of Turkey&#039 / s Carbon Dioxide Problem By Numerical Modeling

Can, Ali 01 February 2006 (has links) (PDF)
CO2 emission is very important, because it is responsible for about 60% of the &quot / Greenhouse Effect&quot / . The major objectives of this study were to prepare a CO2 emission inventory of Turkey based on districts and provinces by using the fuel consumption data with respect to its sources, to find the CO2 uptake rate of forests in Turkey based on provinces and districts, and to estimate the ground level concentration of CO2 across Turkey using U.S. EPA&#039 / s ISCLT3 model for the preparation of ground level concentration maps. The basic sources of the CO2 emission were taken as households, manufacturing industries, thermal power plants and road vehicles. The sinks of the CO2 were forests. The CO2 uptake by forests was calculated using the annual increment of forest biomass. The results of the CO2 emission inventory conducted in this study between the years 1990 and 2003 showed that the CO2 emission in 1990 was 142.45 million tones/year and the highest emission was calculated in 2000 with a value of 207.97 million tones/year. The regional distribution of CO2 emission showed that the Marmara Region emits the highest regional CO2 emission throughout the years with an average value of 54.76 million tones/year. It was also calculated that Marmara and Aegean Regions are responsible for half of the CO2 emission of Turkey. The results of the CO2 uptake calculations showed that the CO2 uptake of forests in the coastal zone was higher that that in the inland zone. The CO2 uptake in the Central Anatolia, Eastern Anatolia and South-Eastern Anatolia Regions were 2.6, 1.9 and 1.1 million tones/year, respectively. The maximum CO2 uptake is in the Black Sea Region with a value of 16.4 million tones/year. The highest ground level CO2 concentartions without any sink effect were always obtained in the Marmara Region. However, the forest areas in this region decrease the concentrations considerably. The dispersion model performance is determined highly without the results of the year 2002.
12

Evaluation des émissions et de la modélisation de la qualité de l'air sur Beyrouth et le Liban / evaluation of the emissions and air quality modeling over beirut and lebanon

Abdallah, Charbel 13 December 2016 (has links)
Face aux problèmes sanitaires et environnementaux liés à la pollution atmosphérique au Liban, les études se multiplient pour permettre une bonne compréhension de la situation, dont des mesures de la qualité de l’air et des études sur les émissions de polluants et sur la modélisation des concentrations dans l’atmosphère à l’aide du modèle de chimie transport (CTM) de WRF/Polyphemus. Pour modéliser la qualité de l’air au Liban, les études précédentes se sont heurtées à différentes difficultés dont : une surestimation des concentrations d’ozone d’un facteur 2 dans les résultats de la modélisation WRF/Polyphemus pour l’été 2012, un profil d’émission des COV issus du transport routier différent de ceux que l’on trouve dans les pays développés. De cela dérivent les objectifs de cette thèse : améliorer les performances de Polyphemus pour le Liban, notamment en améliorant la représentation des conditions aux limites du modèle, évaluer le modèle pour l’année 2014 vis-à-vis des nouvelles observations du réseau national de la qualité de l’air, mesurer les facteurs d’émissions du transport routier dans un tunnel à Beyrouth et les comparer aux données des pays développés. Afin d’améliorer les performances du CTM pour le Liban, cette thèse compare les concentrations simulées avec deux inventaires d’émissions différents et avec différentes méthodes de calcul des conditions aux limites. Pour les émissions, deux inventaires sont comparés : un inventaire récemment mise en place pour le Liban et l’inventaire d’émission global EDGAR-HTAP, qui combine des émissions mesurées pour les pays développés et des émissions modélisées pour les autres pays. Bien que cet inventaire soit couramment utilisé dans les modèles globaux de qualité de l’air d’importantes différences d’estimation et de distribution spatiale sont identifiées par rapport à l’inventaire spécifique du Liban. Dans les simulations des études précédentes réalisées sur le Liban, les conditions aux limites étaient obtenues à partir de simulations globales avec le modèle MOZART-4. Un domaine régional sur le Moyen-Orient est introduit dans la chaine de modélisation afin d’amortir le changement de résolution entre les résultats le modèle global (≥ 1°) et le domaine du Liban (0.055°). Ce changement a permis d’améliorer considérablement les résultats de la modélisation des polluants au Liban, surtout pour l’ozone. Cette nouvelle configuration de modélisation (domaines emboités, Moyen Orient puis Liban) est ensuite employée pour la modélisation de l’année 2014 et évaluée vis-à-vis des observations faites par le réseau national de mesure de la qualité de l’air. Les performances du modèle pour la représentation des polluants de qualité de l’air sont satisfaisantes par rapport aux indicateurs disponibles dans la littérature. Cependant, la modélisation météorologique pourrait être améliorée, et il serait souhaitable de prendre en compte l’impact sur les émissions des changements démographiques entre l’année pour laquelle l’inventaire a été conçu (2011) et l’année modélisée (2014) en raison du déplacement de population suite à la guerre en Syrie.En ce qui concerne des facteurs d’émission (FE) du transport routier, nous avons effectué une campagne de mesure au tunnel Salim Slam à Beyrouth en 2014. Les facteurs d’émissions de différents polluants (CO, NOx, PM2.5, COV) ont été mesurés pour l’ensemble du trafic. En comparaison à la littérature, les FE locaux sont toujours supérieurs aux FE des pays développés même s’ils ont tendances à être réduits par rapport aux valeurs mesurés en 2000 suites aux changements du parc automobile et son évolution / Because of health and environmental problems related to air pollution in Lebanon, the number of studies investigating this matter has increased over the years to ensure a proper understanding of the situation, including measurements of air quality, studies on pollutant emissions and modeling of atmospheric concentrations using the chemistry transport model (CTM) WRF/Polyphemus. To model air quality in Lebanon, previous studies have identified several difficulties including: an overestimation of ozone concentrations by a factor of 2 in the modeling results of WRF/Polyphemus during summer 2012, a local VOC emission profile from road transport that is different from those found in developed countries. Consequently, the objectives of this thesis are: to improve the performance of Polyphemus over Lebanon by improving the boundary conditions of the simulation of, to evaluate the model for the year 2014 using new observations provided by the national air quality monitoring network, to measure emission factors from road transport in a tunnel in Beirut and compare those data to those observed in developed countries. To improve the performance of the CTM over Lebanon, this thesis compares the concentrations simulated with two different emission inventories and with different methods of estimating boundary conditions. For emissions, two inventories are compared: one that was recently set up specifically for Lebanon, and a global inventory, called EDGAR-HTAP, which combines measured emissions for developed countries and modelled emissions for the remaining countries Even though EDGAR-HTAP is commonly used in global air-quality models, significant differences in the estimation and the spatial distribution of the emissions are identified compared to the inventory specifically developed for Lebanon. In the simulations of the previous studies over Lebanon, boundary conditions were estimated using global simulations from the model MOZART-4. A regional domain over Middle East is introduced into the modeling chain to cushion the change in the horizontal resolution between the global model (≥ 1°) and the Lebanon domain (0.055°). The results from this change showed a significant improvement in the model performance over Lebanon, especially for ozone. This new modeling configuration (nested domains, Middle East and Lebanon is then used to model the year 2014 and it is evaluated using the observations provided by the national air quality monitoring network. For air-quality pollutants, the model performance is satisfactory, as using published criteria. However, weather modeling (Wind speed and Direction) should be improved, and we should take into account the impact on emissions of the demographic changes between the year for which inventory was designed (2011) and the modeled year (2014) due to the population displacement induced by the Syrian war.Concerning emission factors (EF) of road transport, we performed a measurement campaign at the Salim Slam tunnel in Beirut in 2014. The emission factors for the different pollutants (CO, NOx, PM2.5, VOC) were measured for the average traffic. Compared to other studies, the local EF are higher than those measured in developed countries even though they tend to be reduced, as a result of the changes in the fleet characteristics, compared to the values measured back in 2000
13

The development of an ‘emission inventory tool’ for brickmaking clamp kilns

Akinshipe, Oladapo Bola January 2013 (has links)
An emission inventory tool for estimating SO2, NO2, and PM10 emissions from brick clamp kiln sites was developed from investigations performed on three representative South African clamp kiln sites in order to facilitate application for Atmospheric Emission Licenses (AELs) from these sources. The tool utilizes readily available site-specific parameters to generate emission factors for significant activities that emit the aforementioned pollutants. PM10 emission factors for significant processes were developed using empirical expressions from the Compilation of Air Pollutant Emission Factors (AP-42) documents. SO2 emission factor for clamp kiln firing was obtained from “reverse-modelling”, a technique that integrates ambient monitoring and dispersion modelling (using Atmospheric Dispersion Modelling System software) to “standardize” actual emission rate from an assumed rate of 1 g/s. The use of multiple point sources proved to improve the simulation of the buoyancy-induced plume rise; therefore, a “bi-point” source configuration was adopted for the kiln. The “reverse-modelling” technique and “bi-point” source configuration produced SO2 emission rates differing from -9 % to +22 % from mass balance results, indicating that the “reverse-modelling” calculations provide reliable emission estimates for SO2. An NO2 emission factor could not be obtained from the “reverse-modelling” technique due to experimental errors and the significant effect of NO2 emissions from other onsite air emission sources such as internal combustion engines. The NO2 emission factor was obtained from previous comprehensive study on a similar clamp kiln site. The emission factors obtained from this study were utilized in developing an “emission inventory tool” which is utilized by clay brick manufacturers in quantifying air emissions from their sites. Emissions quantification is a requirement for brick manufacturers to obtain an AEL which is regulated under South African environmental laws. It is suggested that the technique used here for SO2 emission confirmation could be used to estimate emissions from a volume or area source where combustion occurs and where knowledge of the source parameters is limited. / Dissertation (MSc)--University of Pretoria, 2013. / gm2014 / Chemical Engineering / unrestricted
14

A carbon budget for Rostock: Suggestions for a fair local contribution to the Paris Agreement in view of current climate targets

Lukow, Luise January 2020 (has links)
The increase of global average temperature depends linearly on the amount of carbon dioxide that is accumulating in the atmosphere. Consequently, the determination of a temperature target that should not be exceeded, corresponds to an amount of carbon dioxide that can still be emitted. This is referred to as a carbon budget. With the Paris Agreement, a global commitment to such a target exists. The signatories have pledged to hold “the increase in global average temperature to well below 2°C […] and to pursue efforts to limit the temperature increase to 1.5°C”. Although the wording leaves room for interpretation, the Paris Agreement can hence be translated into a remaining global carbon budget. The distribution of this budget amongst countries can be a way to close the gap between the committed target and Nationally Determined Contributions, which are submitted by each country but currently expected to lead to a warming of more than 2°C. Taking the concept of national carbon budgets further and sharing them out on a smaller scale can support municipalities in framing their mitigation targets and planning measures accordingly. In this regard, the aim of this thesis was to calculate a Paris-compliant carbon budget for the city of Rostock, Germany. This was done by sharing out the remaining global carbon budget amongst countries based on the notion of ‘common but differentiated responsibilities and respective capabilities’, which is part of the Paris Agreement. To reflect on this notion two different country classifications were applied which resulted in carbon budgets for Germany of 4 450 and 6 200 MtCO2 respectively up from 1st January 2021. For a share between German municipalities, the grandfathering principle was applied. It allocates a budget to a municipality depending on the proportion in national emissions. An inventory, which was prepared for this purpose, revealed that Rostock’s territorial emissions accounted for 0.12% of all-German emissions in 2017. Based on this share, Rostock would receive a budget of 5 500 to 7 600 ktCO2 up from 2021, depending on the country classification. The thesis found further that current mitigation targets were falling short of complying with the Paris Agreement. Currently, both Germany and Rostock are basing their efforts on budgets two to three times larger than what can be considered a fair contribution.
15

PUBLIC HEALTH RISK BASED PRIORITIZATION OF HAZARDOUS AIR POLLUTANTS FROM INDUSTRIAL SOURCES : A CASE STUDY FOR A PETROLEUM REFINERY IN SOUTHEAST ASIA / 産業起源有害大気汚染物質の公衆衛生リスクに基づく優先順位付け:東南アジアの石油精製所におけるケーススタディ

Maihani, Binti Ismail 23 March 2021 (has links)
京都大学 / 新制・課程博士 / 博士(工学) / 甲第23182号 / 工博第4826号 / 新制||工||1754(附属図書館) / 京都大学大学院工学研究科都市環境工学専攻 / (主査)教授 米田 稔, 教授 高野 裕久, 教授 松井 康人 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM
16

Application of a Mobile Flux Lab for the Atmospheric Measurement of Emissions (FLAME)

Moore, Tim Orland II 14 October 2009 (has links)
According to the World Health Organization, urban air pollution is a high public health priority due its linkage to cardio-pulmonary disease and association with increased mortality and morbidity (1, 2). Additionally, air pollution impacts climate change, visibility, and ecosystem health. The development of effective strategies for improving air quality requires accurate estimates of air pollutant emissions. In response to the need for new approaches to measuring emissions, we have designed a mobile Flux Lab for the Atmospheric Measurement of Emissions (FLAME) that applies a proven, science-based method known as eddy covariance for the direct quantification of anthropogenic emissions to the atmosphere. The mobile flux lab is a tool with novel, multifaceted abilities to assess air quality and improve the fidelity of emission inventories. Measurements of air pollutant concentrations in multiple locations at the neighborhood scale can provide much greater spatial resolution for population exposure assessments. The lab's mobility allows it to target specific sources, and plumes from these can be analyzed to determine emission factors. Through eddy covariance, the lab provides the new ability to directly measure emissions of a suite of air pollutants. We have deployed the FLAME to three different settings: a rural Appalachian town where coal transport is the dominant industry; schools in the medium-sized city of Roanoke, Virginia; and the large urban areas around Norfolk, Virginia, to measure neighborhood-scale emissions of air pollution. These areas routinely experience high ozone and particulate matter concentrations and include a diverse array of residential neighborhoods and industries. The FLAME is able to capture emissions from all ground-based sources, such as motor vehicles, rail and barge traffic, refuse fires and refueling stations, for which no direct measurement method has been available previously. Experiments focus on carbon dioxide (CO₂), the principal greenhouse gas responsible for climate change; nitrogen oxides (NOx), a key ingredient in ground-level ozone and acid rain; volatile organic compounds (VOCs), a second key ingredient in ozone and many of which are air toxics; and fine particulate matter (PM2.5), a cause of mortality, decreased visibility, and climate change. This research provides some of the first measurements of neighborhood-scale anthropogenic emissions of CO₂, NOx, VOCs and PM2.5 and as a result, the first opportunity to validate official emission inventories directly. The results indicate that a mobile eddy covariance system can be used successfully to measure fluxes of multiple pollutants in a variety of urban settings. With certain pollutants in certain locations, flux measurements confirmed inventories, but in others, they disagreed by factors of up to five, suggesting that parts of the inventory may be severely over- or underestimated. Over the scale of a few kilometers within a city, emissions were highly heterogeneous in both space and time. FLAME-based measurements also confirmed published emission factors from coal barges and showed that idling vehicles are the dominant source of emissions of air toxics around seven schools in southwest Virginia. Measurements from this study corroborate existing emission inventories of CO₂ and NOx and suggest that inventories of PM2.5 may be overestimated. Despite the tremendous spatial and temporal variability in emissions found in dense urban areas, CO₂ fluxes on average are very similar across the areas in this study and other urban areas in the developed world. Nevertheless, the high level of variability in spatial and temporal patterns of emissions presents a challenge to air quality modelers. The finding that emissions from idling vehicles at schools are likely responsible for creating hot spots of air toxics adds to the urgency of implementing no-idling and other rules to reduce the exposure of children to such pollutants. Ultimately, the results of this study can be used in combination with knowledge from existing emission inventories to improve the science and policies surrounding air pollution. / Ph. D.
17

Développements méthodologiques pour la modélisation hybride : conséquences pour l'analyse de la politique climatique dans une économie ouverte (France) / Methodological proposal for hybrid modelling : consequences for climate policy analysis in an open economy (France)

Le Treut, Gaëlle 09 November 2017 (has links)
Cette thèse aborde les enjeux de l'hybridation des données pour la modélisation énergie-économie-environnement, et ses implications pour la politique climatique dans le cas de la France.Le travail met l'accent sur l'importance de construire une représentation hybride de l'économie, articulant de façon cohérente le cadre économique de la comptabilité nationale et les flux physiques, fournis par des bilans de matières (ex: bilan énergétique). Partant du principe qu’il est possible de réduire les incertitudes dans la recomposition des données grâce à des contraintes d’équilibres de flux, cette thèse met d’abord en place une méthode permettant de dépasser les problèmes de nomenclatures non cohérentes, de données disparates, ou simplement manquantes. Nous montrons que l’hybridation permet de décrire plus précisément le poids de l’énergie dans l’appareil productif français, ainsi que celui de certains secteurs de l’économie (ciment, acier).Le cadre hybride sert alors de base au modèle d’équilibre général IMACLIM. Ce modèle sert à explorer dans quelle mesure la comptabilité hybride permet de renouveler la discussion sur l’introduction d’une taxe carbone unilatérale en France.Nous mesurons d’abord l’importance de la procédure d’hybridation dans l’évaluation de l’impact macroéconomique de la politique climatique. La désagrégation sectorielle nous permet, dans un second temps, de conduire une discussion autour de paramètres centraux mais controversés de la modélisation : les élasticités-prix du commerce international, et la courbe salaire-chômage interprétée comme un indicateur du pouvoir de négociation des salaires. La thèse montre en particulier qu’il est possible, grâce au progrès sur la description sectorielle, de prendre en compte une hétérogénéité des régimes de formations salariales entre secteurs tout en les reliant à leur niveau d’exposition au commerce extérieur.Enfin, la thèse propose une méthode pour évaluer différents inventaires des émissions de CO2, tels que les émissions liées à la consommation, ou les émissions incorporées dans les importations, tout en s’appuyant sur le cadre hybride. Ainsi, nous fournissons des informations originales sur les moteurs des émissions en France qui permettront de prolonger l’analyse à d’autres mesures tels que l'ajustement d’une taxe carbone aux frontières / This thesis addresses the issue of data hybridisation for energy-economy-environment modelling and its implications for climate policy in the case of France.The work emphasises the importance of building a hybrid representation of the economy, articulating coherently the economic framework of national accounts and the physical flows, provided by sectoral database (energy balance, industrial statistics). Assuming that it is possible to reduce the uncertainties of data construction, thanks to the equilibrium constraints of flows, this thesis first introduces a method which overcomes the problems of non-coherent nomenclatures, disparate data, or simply missing ones. We show that this hybridisation procedure allows to better describe the weight of both the energy in the French productive system and key sectors of the economy (cement, steel).The hybrid framework then serves to feed the IMACLIM general equilibrium model. The model is used to explore to what extent the hybrid accounts give an opportunity to renew discussion on the introduction of a unilateral carbon tax in France.We first measure the importance of the hybridisation procedure for assessing the macroeconomic impact of climate policy.Then, the sectoral disaggregation allows us to conduct a discussion around central but controversial parameters of modelling: the international trade elasticity and the wage curve interpreted as an indicator of the wage bargaining power. The thesis shows in particular that it is possible, thanks to the progress on the sectoral description, to take into account heterogeneous representation of wage formation between sectors while linking them to their level of exposure to external trade.Finally, the thesis proposes a methodology to evaluate different emission inventories of CO2, such as "consumption-based" emissions, and emissions embodied in imports while relying on the hybrid framework. We thus provide original insights on the drivers of emissions in France which could extend the analyses to other policies such as the adjustment of a carbon tax at the borders
18

Mobile Laboratory Measurement of Black Carbon, Particulate Polycyclic Aromatic Hydrocarbons and Other Exhaust Emissions in Mexico City

Jiang, Mei 28 March 2005 (has links)
Black carbon (BC) and polycyclic aromatic hydrocarbons (PAHs) are two atmospheric pollutants produced by motor vehicles using carbonaceous fuels. As a part of the Mexico City Project, measurements of BC, PPAHs and many other gas- and particle-phase emissions were measured in Mexico City using a mobile laboratory during the Mexico City Metropolitan Area field campaign in April 2003 (MCMA-2003). The main goal of this research is to estimate emissions of BC and particulate PAHs (PPAHs) for Mexico City's vehicle fleet. The emissions of gas-phase pollutants such as carbon monoxide (CO), total nitrogen oxides (NOy) and volatile organic compounds (VOC) are also estimated. The mobile lab has previously been used to chase vehicles and measure their emissions, but analysis has traditionally focused on determining emission factors of individual vehicles associated with specific chasing events. The laboratory continuously samples ambient air from an inlet at the front of the van, and it is always "seeing" exhaust plumes from the vehicles around it while driving through traffic. We have developed an algorithm that automatically identifies the exhaust plume measurement points, which are then used as the basis for calculation of emission factors. In the nearly 90 hours of on-road sampling during the field campaign, we have identified ~30,000 exhaust measurement points. The large sample size enables us to estimate fleet-average emission factors and thus the emission inventory. Motor vehicles are estimated to emit annually 1,960 tons of BC, 56.2 tons of PPAHs, 1,320,000 tons of CO, 125,000 tons of NOy and 2440 tons of VOCs. The spatial and temporal patterns of BC and PPAHs in different locations with in MCMA are also studied. / Master of Science
19

Flux Measurements of Volatile Organic Compounds from an Urban Tower Platform

Park, Chang Hyoun 2010 May 1900 (has links)
A tall tower flux measurement setup was established in metropolitan Houston, Texas, to measure trace gas fluxes from both anthropogenic and biogenic emission sources in the urban surface layer. We describe a new relaxed eddy accumulation system combined with a dual-channel gas chromatography - flame ionization detection used for volatile organic compound (VOC) flux measurements in the urban area, focusing on the results of selected anthropogenic VOCs, including benzene, toluene, ethylbenzene and xylenes (BTEX), and biogenic VOCs including isoprene and its oxidation products, methacrolein (MACR) and methyl vinyl ketone (MVK). We present diurnal variations of concentrations and fluxes of BTEX, and isoprene and its oxidation products during summer time (May 22 - July 22, 2008) and winter time (January 1 - February 28). The measured BTEX values exhibited diurnal cycles with a morning peak during weekdays related to rush-hour traffic and additional workday daytime flux maxima for toluene and xylenes in summer time. However, in winter time there was no additional workday daytime peaks due mainly to the different flux footprints between the two seasons. A comparison with different EPA National Emission Inventories (NEI) with our summer time flux data suggests potential underestimates in the NEI by a factor of 3 to 5. The mixing ratios and fluxes of isoprene, MACR and MVK were measured during the same time period in summer 2008. The presented results show that the isoprene was affected by both tail-pipe emission sources during the morning rush hours and biogenic emission sources in daytime. The observed daytime mixing ratios of isoprene were much lower than over forested areas, caused by a comparatively low density of isoprene emitters in the tower's footprint area. The average daytime isoprene flux agreed well with emission rates predicted by a temperature and light only emission model (Guenther et al., 1993). Our investigation of isoprene's oxidation products MACR and MVK showed that both anthropogenic and biogenic emission sources exist for MACR, while MVK was strongly dominated by a biogenic source, likely the isoprene oxidation between the emission and sampling points.

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