Present-day numerical air quality models are considered essential tools for predicting future air pollutant concentrations and depositions, contributing to the development of new effective strategies for the control and the reduction of pollutant emissions. They simulate concentrations and depositions of pollutants on a wide range of scales (global, national, urban scale) and they are used for identifying critical areas, integrating measurements and achieving a deeper scientific understanding of the physical and chemical processes involving air pollutants in the atmosphere. The use of comprehensive air quality models started in the late 1970s and since then their development has increased rapidly, hand in hand with the rapid increase in computational resources. Today more and more complex and computationally expensive numerical models are available to the scientific community. One of these tools is the Community Multi-Scale Air Quality System (CMAQ), developed in the 1990s by the US Environmental Protection Agency (EPA) and currently widely applied across the world for air pollution studies. This work focuses on the application of CMAQ to the United Kingdom, for estimating concentrations and depositions of acidifying pollutants (NOX, NHX, SOX) on a national scale. The work is divided into seven chapters, the first one describing the main issues related to the emission and dispersion in the atmosphere of acidifying species. It also includes a brief overview of the main international policies signed in the last thirty years in order to reduce the problem of acidification in Europe, as well as a brief description of some models mentioned in this thesis. The second one describes the main features of CMAQ and addresses some issues such as the use of a nesting process for achieving temporally and spatially resolved boundary concentrations, and the implementation of the model on parallel machines, essential for reducing the simulation computing time. It also describes how this study is part of a wider context, which includes the application of CMAQ in the United Kingdom by other users with different scientific purposes (aerosols processes, air quality in the urban area of London, contribution of UK power stations to concentrations and depositions etc.). The third part of the thesis focuses on the application and evaluation over the United Kingdom of the 5th Generation Mesoscale Model MM5, used for providing 3D meteorological input fields to CMAQ. This study was performed assuming that an accurate representation of depositions and concentrations of chemical species cannot be achieved without a good estimate of the meteorological parameters involved in most of the atmospheric processes (transport, photochemistry, aerosol processes, cloud processes etc.). The fourth part of the thesis describes the preliminary implementation of the Sparse Matrix Operational Kernel Emission System (SMOKE) in the United Kingdom. The processor provides input emissions to CMAQ. The use of SMOKE is usually avoided in CMAQ applications of outside America, and CMAQ input emission files are prepared by the application of other software. The reason is that the model requires radical changes for being applied outside Northern and Central America. Some of these changes have been made in this study such as the adaptation of the European emission inventory EMEP and the UK National Inventory NAEI to the modelling system for point and area sources, the introduction of new European emission temporal profiles in substitution of the American ones and the introduction of new geographical references for the spatial allocation of emissions. In the fifth chapter the results of CMAQ application over the UK are discussed. The study focuses on NOX, SO2, NH3 and + 4 NH . Maps of concentration are presented and modelled data are compared to measurements from two different air quality networks in the UK. An analysis of the performance of CMAQ over the UK is also performed. In the final chapter an annual inter-comparison between CMAQ and the Lagrangian transport model FRAME is carried out. Maps of annual wet deposition fluxes of NHX, NOY and SOX for year 1999 are presented. The results of both models are compared to one another and they are also compared to values from the UK official data set CBED. Finally, the last chapter suggests the work that has to be done in the future with CMAQ and it summarizes the conclusions.

White Island and Ruapehu are currently the most active volcanoes in New Zealand. During non-eruptive periods, intense quiescent degassing through fumaroles can occur. The current project studies the quiescent degassing plumes, including aerosol sampling on White Island and dispersion modelling of SO₂ and PM₁₀ from White Island and Ruapehu volcanoes. Aerosol sampling from fumaroles at the crater floor on White Island volcano was carried out on 9 February and 6 April 2005. The exposed filters were analysed for various anions and cations and the particle mass concentration and molar concentration determined. Major elemental constituents were sodium and chlorine (Na⁺: 413 µg m⁻³, Cl⁻: 1520 µg m⁻³), which show best correlation at both sampling sessions. Other ions detected, with little correlation, are Ca²⁺, PO₄³⁻ and to a certain extent Mg²⁺. Other constituents found, which cannot correlate explicitly to other ions, are K⁺, NH₄⁺, NO₃⁻, and SO₄²⁻. SEM study of one exposed filter was performed and mainly NaCl particles could be distinguished due to their well-defined cubic shape. The Air Pollution Model (TAPM) was used for dispersion modelling of SO₂ (models 1-4) and PM₁₀ (models 5 and 6) from White Island and Ruapehu volcanoes. Annual modelling was performed using different parameters of emission rate, exit temperature and exit velocity. The resulting plume dispersions show relatively low concentrations at ground level ≤10 m), particularly for the models of PM₁₀ dispersion. TAPM calculated the highest SO₂ ground level concentrations with model 4, where the NES values of 350 and 570 µg m⁻³ were exceeded several times. The data was then used for detailed hazard assessment of urban population in the North Island. The meteorological data from annual modelling was used for model evaluation and compared with observation data from different weather stations by statistical calculations. Overall, TAPM performed well with most good and very good results. To evaluate SO₂ dispersion modelling, airborne plume measurements were carried out on 22 November 2006 by plume traverses at 3, 10 and 20 km. Although there is some variation, the calculated correlation coefficients indicate good model results for two plume traverses at 3 and 20 km and one plume traverse at 10 km. The meteorological data was also used for model evaluation, and the results indicate good model performance. TAPM is therefore suggested for future studies when more observation data are available to verify the calculated model data.

White Island and Ruapehu are currently the most active volcanoes in New Zealand. During non-eruptive periods, intense quiescent degassing through fumaroles can occur. The current project studies the quiescent degassing plumes, including aerosol sampling on White Island and dispersion modelling of SO₂ and PM₁₀ from White Island and Ruapehu volcanoes. Aerosol sampling from fumaroles at the crater floor on White Island volcano was carried out on 9 February and 6 April 2005. The exposed filters were analysed for various anions and cations and the particle mass concentration and molar concentration determined. Major elemental constituents were sodium and chlorine (Na⁺: 413 µg m⁻³, Cl⁻: 1520 µg m⁻³), which show best correlation at both sampling sessions. Other ions detected, with little correlation, are Ca²⁺, PO₄³⁻ and to a certain extent Mg²⁺. Other constituents found, which cannot correlate explicitly to other ions, are K⁺, NH₄⁺, NO₃⁻, and SO₄²⁻. SEM study of one exposed filter was performed and mainly NaCl particles could be distinguished due to their well-defined cubic shape. The Air Pollution Model (TAPM) was used for dispersion modelling of SO₂ (models 1-4) and PM₁₀ (models 5 and 6) from White Island and Ruapehu volcanoes. Annual modelling was performed using different parameters of emission rate, exit temperature and exit velocity. The resulting plume dispersions show relatively low concentrations at ground level ≤10 m), particularly for the models of PM₁₀ dispersion. TAPM calculated the highest SO₂ ground level concentrations with model 4, where the NES values of 350 and 570 µg m⁻³ were exceeded several times. The data was then used for detailed hazard assessment of urban population in the North Island. The meteorological data from annual modelling was used for model evaluation and compared with observation data from different weather stations by statistical calculations. Overall, TAPM performed well with most good and very good results. To evaluate SO₂ dispersion modelling, airborne plume measurements were carried out on 22 November 2006 by plume traverses at 3, 10 and 20 km. Although there is some variation, the calculated correlation coefficients indicate good model results for two plume traverses at 3 and 20 km and one plume traverse at 10 km. The meteorological data was also used for model evaluation, and the results indicate good model performance. TAPM is therefore suggested for future studies when more observation data are available to verify the calculated model data.

付記する学位プログラム名: グローバル生存学大学院連携プログラム / 京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第20341号 / 工博第4278号 / 新制||工||1662(附属図書館) / 京都大学大学院工学研究科社会基盤工学専攻 / (主査)教授 寶 馨, 教授 立川 康人, 准教授 佐山 敬洋 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

<p>Indoor air quality in office buildings can impact the health, well-being, and productivity of occupants. In most buildings, occupants exhaled breath is the primary source of carbon dioxide (CO₂). Concentrations of indoor CO₂ are also strongly associated with the operational mode of the mechanical ventilation system. While CO2 is routinely monitored in indoor environments, there are few spatially-resolved real-time measurements of CO₂ throughout mechanical ventilation systems. Such measurements can provide insight into indoor- and outdoor-generated CO₂ dispersion throughout a building and between the building and the outdoor atmosphere. This thesis aims to investigate spatiotemporal variations in CO₂ concentrations and mass fluxes throughout a mechanical ventilation system of a living laboratory office in a LEED-certified building. The impact of human occupancy patterns and ventilation conditions of CO₂ concentrations and fluxes was evaluated. </p> <p>A four-month measurement campaign was conducted in one of the four living laboratory offices at the Ray W. Herrick Laboratories. The living laboratory offices feature precise control and monitoring of the mechanical ventilation system via an advanced building automation system. Various mechanical ventilation modes were implemented, such as variable outdoor air exchange rates (AERs) and recirculation ratios. A novel multi-location sampling manifold was used to measure CO₂ at eight locations throughout the ventilation system, such as across the outdoor, supply, and return air ducts. Office occupancy was measured via a chair-based temperature sensor array. Volumetric airflow rate data and CO₂ concentration data were used to estimate CO₂ mass fluxes through the ventilation system. The CO₂ mass flux for the outdoor and exhaust air was used to evaluate the net CO₂ transport from the office to the outdoor atmosphere. </p> <p>The measurements demonstrate that there exist significant spatiotemporal variations in CO₂ concentrations across the outdoor, supply, and return air ducts. CO₂ concentrations varied with human occupancy in the office and the outdoor AER of the mechanical ventilation system. Due to human-associated CO₂ emissions, the net CO₂ mass flux from the office to the outdoor environment was approximately 700 kg of CO₂ per year. Thus, occupied offices may represent an important, yet unrecognized, source of CO₂ to the urban atmosphere.</p>

Environmental modelling is lately becoming to be one of the most important decision support systems. Hydrological models present significant potential for use especially in area of surface and groundwater protection. In the diploma thesis, the Soil and Water Assessment Tool (SWAT) was used to evaluate nitrate surface water pollution in nine catchments situated in Křivoklátsko protected area during the period of 2003 - 2010. Modelling process consist of assorted consequent steps. First the hydrological model of each catchment was created. Afterwards the sensitivity analysis was conducted to select most sensitive model parameters. Calibration process was carried out after the parameters selection using SWAT-CUP automatic calibration tool. Model results were visualized and evaluated. The results of the model suggested, that the area of interest was not widely endangered by nitrate pollution. Within each catchment the critical source areas of nitrate pollution were identified. It was observed that these areas are related with intensive agricultural areas. Nitrate leaching ranged from 6 kg.ha-1 to 10 kg.ha-1 per year in agriculture areas. Some areas exceed this amount. Nitrate loss from most of the area of interest ranged from 0 kg.ha-1 to 4 kg.ha-1 per year. Concentrations of nitrates in modeled...

Accurate modeling of contaminant transport and sorption processes in the soil and landfill liners is a prerequisite for realistic model simulations of contaminant fate and transport in the environment. These studies are also important for the remediation of soil and groundwater contamination. Modeling of contaminant transport through soils and landfill liners consists of either solving the direct/forward problem or the inverse problem. In this thesis, an automated time-stepping implicit procedure is developed from the convergence and error studies of explicit and implicit finite-difference solutions for the advection-dispersion transport of contaminants through soil with different sorption mechanisms. This study is further extended for transient through-diffusion (TTD) transport of contaminant in landfills by considering linear sorption mechanism. To validate the numerical solution and also to study the behavior of finite-difference numerical solutions for TTD transport problem, closed-form analytical solution is derived. Further, a new interface condition is proposed based on the finite-volume procedure for stratified soil or landfill liner system. Solvers are developed for the parameter estimation of inverse problem by integrating the developed procedures for the above forward problem with different optimization procedures. Solvers based on Simulated Annealing (SA) and Genetic Algorithm (GA) are developed for TTD transport in the landfill liners and verified with the existing methods of parameter estimation. Novel swarm intelligence based solver is developed for the first time for parameter estimation in contaminant transport inverse problem to overcome some of the limitations of the classical optimization methods and evolutionary methods such as GA. Additionally, the proposed swarm intelligence based algorithms and a new variant is applied to solve ill-posed problem of contaminant source characterization. The presented work in this dissertation can be unswervingly applied for modeling the contaminant transport in laboratory through-diffusion tests and contaminant transport through landfill liners where the transport is usually considered to be one-dimensional and also diffusion-dominated. Similarly, the advection-dispersion transport through laboratory soil columns can also be modeled with the developed, fast, automated, implicit numerical procedure with very good accuracy. The present study can be applied further for contaminant transport through stratified soil/liner system using fast converging numerical algorithms. Finally, the problems of design parameter estimation and source characterization can be handled accurately by the use of developed automated nature-inspired solvers.

<p dir="ltr">The goal of this thesis is to develop a method of evaluating long-term IAQ performance of an industrial facility and use machine-learning to model the relationship between critical air pollutants and the facility’s HVAC systems and processes. The facility under study for this thesis is an electroplating manufacturer. The air pollutants at this facility that were studied were particulate matter, total-volatile organic compounds, and carbon-dioxide. Upon sensor installation, seven “zones” were identified to isolate areas of the plant for measurement and analysis. A statistical review of the long-term data highlighted how this facility performed in terms of compliance. Their gaseous pollutants were well within regulation. Particulate matter, however, was found to be a pressing issue. PM10 was outside of compliance more than 15% of the time in five out of seven of the zones of study. Some zones were out of compliance up to 80% of the total collection period. The six pollutants that met these criteria were deemed critical and moved on to machine learning modeling. Our model of best fit for each pollutant used a gaussian process regression model, which fits best for non-linear rightly skewed datasets. The performance of each of our models was deemed significant. Every model had at least a regression coefficient of 0.935 and above for both validation and testing. The maximum average error was 12.64 ug.m^3, which is less than 10% of the average PM10 concentration. Through our modeling, we were able to study how HVAC and production played a role in particulate matter presence for each zone. Exhaust systems of the west side of the plant were found to be insufficient at removing particulates from their facility. Overall, the methods developed in this thesis project were able to meet the goal of analyzing IAQ compliance, modeling critical pollutants using machine learning, and identifying a relationship between these pollutants and an industrial facility’s HVAC and production systems.</p>

<p>This study is focused on the design, production, and operation of a controlled environmental olfaction chamber to evaluate human physiological and emotional response to volatile chemical emissions (VCPs) from scented household products in addition to careful characterization of the volatile organic compounds (VOCs) present in these product emissions. Utilizing proton transfer reaction time-of-flight mass spectrometry, the chamber can collect VCP emissions and identify VOCs present to complete an accurate chemical profile of household and common product emissions not previously known. This instrument is one of the first of its kind and will serve as a key element in understanding the relationship between human physical and cognitive health and the built environment.</p>