Efthimios Tagaris

A Methodology to Estimate Odors around Landfill Sites: The Use of Methane as an Odor Index and Its Utility in Landfill Siting

Abstract The estimation of odor production and dispersion from landfill sites is a very complicated task because of the different chemical species that exist in biogas. To site a new landfill, it is necessary to know the distance that odors can travel around the landfill under atmospheric conditions that increase the concentration of pollutants. Although CH4 is an odorless gas, it can be used as an index to determine the dispersion of low-reactivity odorous species around a landfill site. Methane production rates, estimated by biogas production models, were used by an air dispersion model to determine the spatial distribution of CH4 around landfill sites. By utilizing dispersion models under extreme atmospheric conditions, a maximum CH4 concentration around the landfills was determined. Based on the ratio between CH4 and odorous chemical species, the spatial distribution of the concentration of an odorous species was determined for those species with low reactivity in the atmosphere. For odorous species with high reactivity in the atmosphere, a dispersion-reaction model must be used. In this way, the acceptable distance between new landfills and residential areas can be determined. The proposed methodology could be used as a design tool for those who are interested in landfill siting.

Modeling New Particle Formation During Air Pollution Episodes: Impacts on Aerosol and Cloud Condensation Nuclei

The impact of new particle formation on regional air quality and CCN formation is for the first time explored using the UAM-AERO air quality model. New particles are formed by ternary nucleation of sulfuric acid, ammonia and water; subsequent growth of clusters to large sizes is driven by condensation of sulfuric acid and organic vapors, as described by the recently developed nano-Köhler theory. Application of the model in Athens (GAA) and Marseilles (GMA) reveals higher sulfuric acid condensational sink and gaseous sulfuric acid (hence nucleation rate) for the latter. However, limited quantities of organic vapors in the GMA inhibit the growth of the formed clusters; therefore new particle formation is more efficient in the GAA. A sensitivity analysis demonstrates that (1) uncertainty in vaporization enthalpy does not affect organic carbon formed by nucleation, and (2) an accommodation coefficient of unity gives excellent agreement of condensation sink with in-situ observations. Nucleation affects the aerosol size distribution, and can be an important contributor to CCN; locally it can be more important than chemical ageing of pre-existing aerosols.

An estimation of the spatial distribution of agricultural ammonia emissions in the Greater Athens Area

An assessment of the magnitude and the spatial distribution of ammonia emissions originating from agricultural practices in the Greater Athens Area (GAA) is performed due to the primary role of ammonia in aerosol formation. As no emission factors are available for the area of interest, the emissions were estimated using typical emission factors for the emissions from animals, fertilized and unfertilized cultures, as well as the 1996 primary statistical data of the agricultural census for the GAA. Our analysis estimated the annual ammonia emissions from agricultural sources to be approximately 13,250+/-40% t of ammonia per year. This detailed ammonia emission record can and will be used for the study, via modeling, of the serious aerosol problem in the GAA.

Sensitivity of air pollution-induced premature mortality to precursor emissions under the influence of climate change.

The relative contributions of PM2.5 and ozone precursor emissions to air pollution-related premature mortality modulated by climate change are estimated for the U.S. using sensitivities of air pollutants to precursor emissions and health outcomes for 2001 and 2050. Result suggests that states with high emission rates and significant premature mortality increases induced by PM2.5 will substantially benefit in the future from SO2, anthropogenic NOX and NH3 emissions reductions while states with premature mortality increases induced by O3 will benefit mainly from anthropogenic NOX emissions reduction. Much of the increase in premature mortality expected from climate change-induced pollutant increases can be offset by targeting a specific precursor emission in most states based on the modeling approach followed here.

Development of North American Emission Inventories for Air Quality Modeling under Climate Change

Abstract An assessment of how future climate change will impact regional air quality requires projecting emissions many decades into the future in a consistent manner. An approach that integrates the impact of both the current regulations and the longer-term national and global trends is developed to construct an emissions inventory (EI) for North America for the mid-century in support of a regional modeling study of ozone and particulate matter (PM) less than or equal to 2.5 μm (PM2.5). Because the time horizon of such a distant projection is beyond that of EIs used in typical modeling studies, it is necessary to identify a practical approach that allows the emission projections to account for emission controls and climatic and energy-use changes. However, a technical challenge arises because this requires integration of various different types of information with which emissions from human activities are associated. Often, emission information in global models has less detail and uses coarser spatiotemporal resolution. The method developed here is based on data availability, spatiotemporal coverage and resolution, and future-scenario consistency (i.e., Intergovernmental Panel on Climate Change Special Report on Emissions Scenarios [IPCC SRES] A1B), and consists of two major steps: (1) near-future EI projection (to the year 2020), and (2) longer-term EI projection (to mid-century). The first step is based closely on the U.S. Environmental Protection Agency Clean Air Interstate Rule EI, the Environment Canada EI, as well estimates of Mexico’s EI; whereas the second step follows approaches proposed by the EI from the Integrated Model to Assess the Global Environment (IMAGE), developed by Netherlands’s National Institute for Public Health and the Environment (RIVM). For the United States, the year-2050 emissions for nitrogen oxides (NOx), sulfur dioxide (SO2), PM2.5, anthropogenic volatile organic compounds (VOCs), and ammonia are projected to change by -55, -55, -30, -40, and [H11001]20%, respectively, compared with 2001. NOx and SO2 emission changes are very similar in total amount but different in sectoral contribution. The projected emission trends for Canada and Mexico differ considerably. After taking into account the modeled climate changes, biogenic VOC emission increases from three countries overwhelm the decreases in anthropogenic VOC emissions, leading to a net small increase (~2%) in overall VOC emissions.

Cost Analysis of Impacts of Climate Change on Regional Air Quality

Abstract Climate change has been predicted to adversely impact regional air quality with resulting health effects. Here a regional air quality model and a technology analysis tool are used to assess the additional emission reductions required and associated costs to offset impacts of climate change on air quality. Analysis is done for six regions and five major cities in the continental United States. Future climate is taken from a global climate model simulation for 2049-2051 using the Intergovernmental Panel on Climate Change (IPCC) A1B emission scenario, and emission inventories are the same as current ones to assess impacts of climate change alone on air quality and control expenses. On the basis of the IPCC A1B emission scenario and current control technologies, least-cost sets of emission reductions for simultaneously offsetting impacts of climate change on regionally averaged 4th highest daily maximum 8-hr average ozone and yearly averaged PM2.5 (particulate matter [PM] with an aerodynamic diameter less than 2.5 μm) for the six regions examined are predicted to range from

Atmospheric methane transport near landfill sites

36 million (1999

Development of risk-based air quality management strategies under impacts of climate change

) yr-1 in the Southeast to

Sensitivity Analysis of Climate Change Projection to the Grid Size Resolution over Mediterranean

5.5 billion yr-1 in the Northeast. However, control costs to offset climate-related pollutant increases in urban areas can be greater than the regional costs because of the locally exacerbated ozone levels. An annual cost of

Specific Case: Regional Estimates of Global Climate Change: A Dynamical Downscaling Approach to Southeast Europe

4.1 billion is required for offsetting climate-induced air quality impairment in 2049-2051 in the five cities alone. Overall, an annual cost of