Download or read book Evaluation of Modeled Emission Inventories of Ozone Precursors written by Wolfgang Seiler and published by . This book was released on 2001 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Evaluation of Modeled Emission Inventories of Ozone Precursors written by and published by . This book was released on 2002 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Summary of Public Comments and EPA Responses on the Draft Report The Role of Ozone Precursors in Tropospheric Ozone Formation and Control written by and published by . This book was released on 1993 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Rethinking the Ozone Problem in Urban and Regional Air Pollution written by National Research Council and published by National Academies Press. This book was released on 1992-02-01 with total page 525 pages. Available in PDF, EPUB and Kindle. Book excerpt: Despite more than 20 years of regulatory efforts, concern is widespread that ozone pollution in the lower atmosphere, or troposphere, threatens the health of humans, animals, and vegetation. This book discusses how scientific information can be used to develop more effective regulations to control ozone. Rethinking the Ozone Problem in Urban and Regional Air Pollution discusses: The latest data and analysis on how tropospheric ozone is formed. How well our measurement techniques are functioning. Deficiencies in efforts to date to control the problem. Approaches to reducing ozone precursor emissions that hold the most promise. What additional research is needed. With a wealth of technical information, the book discusses atmospheric chemistry, the role of oxides of nitrogen (NOx) and volatile organic compounds (VOCs) in ozone formation, monitoring and modeling the formation and transport processes, and the potential contribution of alternative fuels to solving the tropospheric ozone problem. The committee discusses criteria for designing more effective ozone control efforts. Because of its direct bearing on decisions to be made under the Clean Air Act, this book should be of great interest to environmental advocates, industry, and the regulatory community as well as scientists, faculty, and students.
Download or read book Tropospheric Ozone Abatement written by Rainer Friedrich and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 241 pages. Available in PDF, EPUB and Kindle. Book excerpt: The occurrence of high concentrations of ozone during summer episodes in the troposphere over Europe is a problem still unsolved. Although a number· of measures have been implemented that will achieve a further reduction of precursor emissions in the next years, this will not be sufficient to reduce the ozone concentration to levels below thresholds set up to protect human health and plants. Thus, further reductions of emissions of volatile organic compounds and nitrogen oxides are necessary. However, with regard to the increasing costs associated with increasing emission reduction, it is essential to implement abatement strategies, that are effective, i.e. achieving the environmental aim set up, and efficient, i. e. doing this with the least costs possible. In this book, the authors describe the features and the application of a methodology and a model system to identify effective and efficient strategies to reduce ambient concentrations of tropospheric ozone to comply with thresholds set up to protect human health, agricultural crops and ecosystems. Furthermore, macroeconomic impacts of such strategies are addressed and, as burden and benefits of these strategies are not equally distributed between countries, different burden sharing schemes are discussed. The content of this book is based on results of a comprehensive research project, the project INFOS (assessment of policy instruments for efficient ozone abatement strategies in Europe), funded by the European Commission (Directorate General XII) under the Fourth Framework Programme for research, technological development and demonstration activities.
Download or read book Improving Emissions Inventories in North America Through Systematic Analysis of Model Performance During ICARRT and MILAGRO written by Marcelo Andrés Mena and published by . This book was released on 2007 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt: During ICARTT ozone modeling error was improved by updating from the National Emissions Inventory from 1999 and 2001, and furthermore by updating large point source emissions from continuous monitoring data. Further improvements were achieved by reducing area emissions of NOx y 60% for states in the Southeast United States. Ozone error was highly correlated to NOy error during this campaign. Also ozone production in the United States was most sensitive to NOx emissions.
Download or read book Receptor Model Evaluation of Ozone Precursor Emissions During 1994 for Chicago written by Hang Yu and published by . This book was released on 1997 with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Impact of Variable Emissions on Ozone Formation in the Houston Area written by Radovan Thomas Pavlovic and published by . This book was released on 2009 with total page 590 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ground level ozone is one of the most ubiquitous air pollutants in urban areas, and is generated by photochemical reactions of oxides of nitrogen (NOx) and volatile organic compounds (VOCs). The effectiveness of emission reduction strategies for ozone precursors is typically evaluated using gridded, photochemical air quality models. One of the underlying assumptions in these models is that industrial emissions are nearly constant, since many industrial facilities operate continuously at a constant rate of output. However, recent studies performed in the Houston-Galveston-Brazoria area indicate that some industrial emission sources exhibit high temporal emission variability that can lead to very rapid ozone formation, especially when emissions are composed of highly reactive volatile organic compounds. This work evaluates the impact of variable emissions from industrial sources on ground-level ozone formation in Houston area, utilizing a unique hourly emission inventory, known as the 2006 Special Inventory, created as a part of the second Texas Air Quality Study. Comparison of the hourly emissions inventory data with ambient measurements indicated that the impact of the variability of industrial source emissions on ozone can be significant. Photochemical modeling predictions showed that the variability in industrial emissions can lead to differences in local ozone concentrations of as much as 27 ppb at individual ozone monitor locations. The hourly emissions inventory revealed that industrial source emissions are highly variable in nature with diverse temporal patterns and stochastic behavior. Petrochemical and chemical manufacturing flares, which represent the majority of emissions in the 2006 Special Inventory, were grouped into categories based on industrial process, chemical composition of the flared gas, and the temporal patterns of their emissions. Stochastic models were developed for each categorization of flare emissions with the goal of simulating the characterized temporal emission variability. The stochastic models provide representative temporal profiles for flares in the petrochemical manufacturing and chemical manufacturing sectors, and as such serve as more comprehensive input for photochemical air quality modeling.
Download or read book Models in Environmental Regulatory Decision Making written by National Research Council and published by National Academies Press. This book was released on 2007-08-25 with total page 286 pages. Available in PDF, EPUB and Kindle. Book excerpt: Many regulations issued by the U.S. Environmental Protection Agency (EPA) are based on the results of computer models. Models help EPA explain environmental phenomena in settings where direct observations are limited or unavailable, and anticipate the effects of agency policies on the environment, human health and the economy. Given the critical role played by models, the EPA asked the National Research Council to assess scientific issues related to the agency's selection and use of models in its decisions. The book recommends a series of guidelines and principles for improving agency models and decision-making processes. The centerpiece of the book's recommended vision is a life-cycle approach to model evaluation which includes peer review, corroboration of results, and other activities. This will enhance the agency's ability to respond to requirements from a 2001 law on information quality and improve policy development and implementation.
Download or read book Ozone Forming Potential of Reformulated Gasoline written by National Research Council and published by National Academies Press. This book was released on 1999-09-23 with total page 270 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Committee on Ozone-Forming Potential for Reformulated Gasoline was asked whether the existing body of scientific and technical information is sufficient to permit a robust evaluation and comparison of the emissions from motor vehicles using different reformulated gasolines based on their ozone-forming potentials and to assess the concomitant impact of that approach on air-quality benefits of the use of oxygenates within the RFG program. As part of its charge, the committee was asked to consider (1) the technical soundness of various approaches for evaluating and comparing the relative ozone-forming potentials of RFG blends, (2) technical aspects of various air-quality issues related to RFG assessment, and (3) the sensitivity of evaluations of the relative ozone-forming potentials to factors related to fuel properties and the variability of vehicle technologies and driving patterns.
Download or read book Session 125 written by Air & Waste Management Association. Meeting & Exhibition and published by . This book was released on 1989 with total page 110 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Procedures for the Preparation of Emission Inventories for Precursors of Ozone written by U. S. Environmental Protection Agency and published by BiblioGov. This book was released on 2013-07 with total page 250 pages. Available in PDF, EPUB and Kindle. Book excerpt: The U.S. Environmental Protection Agency (EPA) was introduced on December 2, 1970 by President Richard Nixon. The agency is charged with protecting human health and the environment, by writing and enforcing regulations based on laws passed by Congress. The EPA's struggle to protect health and the environment is seen through each of its official publications. These publications outline new policies, detail problems with enforcing laws, document the need for new legislation, and describe new tactics to use to solve these issues. This collection of publications ranges from historic documents to reports released in the new millennium, and features works like: Bicycle for a Better Environment, Health Effects of Increasing Sulfur Oxides Emissions Draft, and Women and Environmental Health.
Download or read book Towards an Integrated Assessment Model for Tropospheric Ozone written by A. A. Olsthoorn and published by . This book was released on 1994 with total page 54 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Leveraging Diverse Observations of Atmospheric Composition and Model Based Sensitivity Analysis to Refine Estimates of Air Pollution Emissions and Impacts written by Congmeng Lyu and published by . This book was released on 2021 with total page 157 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ground-level ozone, which forms photochemically in the atmosphere from precursor emissions of oxides of nitrogen (NOx) and volatile organic compounds, is a criteria pollutant that harms human health and public welfare. For a representative summer episode, premature mortality and potential productivity losses (PPLs) of selected crops and trees attributable to ozone exposure have been quantified using ozone fields from the Community Multiscale Air Quality (CMAQ) model. We applied exposure-response models for the increased risk of premature mortality due to long-term exposure to ozone over a theoretical minimum risk exposure level (TMREL) and for the reduced accumulation of vegetative biomass for four crop species and eleven tree species using the W126 metric designed to capture impacts on plants. To elucidate which emissions contributed to these disbenefits, we applied adjoint-based sensitivity analysis, which efficiently estimates sensitivities of concentration-based metrics with respect to numerous emissions parameters simultaneously. The adjoint of CMAQ was applied to the continental U.S. to calculate the influence of spatially-resolved ozone precursor emissions on the annual average, domain-wide daily maximum 8-hour average over the TMREL (elevated MDA8), premature mortality attributable to exposure to ozone above the TMREL, and PPLs. These quantities provide the impact in terms of the percent reduction in precursor emissions. Additionally, locations where similar percent reductions in ozone precursor emissions would impact one or more endpoints greater than average have been identified. NOx emissions were found to contribute most to the three metrics. The distinct spatial patterns of emissions influences on public welfare disbenefits as compared to the elevated MDA8 and premature mortality suggest that the current regulatory averaging time motivates different emissions control strategies than those that could most directly protect public welfare.Recently, oil and natural gas (O&NG) production activities in the Denver-Julesburg Basin have expanded rapidly. Associated nonmethane hydrocarbon (NMHC) emissions contribute to photochemical formation of ground-level ozone and include benzene as well as other hazardous air pollutants. Using positive matrix factorization (PMF) and chemical mass balance (CMB) methods, we estimate how much O&NG activities and other sources contribute to morning NMHC mixing ratios measured from 2013 to mid-2016 at a site in Platteville, CO, in the Denver-Julesburg Basin, and at a contrasting site in downtown Denver. A novel adjoint sensitivity analysis method is then used to estimate corresponding contributions to ozone and ozone-linked mortality in the Denver region. Average 6 - 9 am NMHC mixing ratios in Platteville were seven times higher than those in Denver in 2013 but four times higher in 2016. CMB estimates that O&NG activities contributed to the Platteville (Denver) site an average of 96% (56%) of NMHC on a carbon basis while PMF indicated 92% (33%). Average vehicle-related contributions of NMHC are estimated as 41% by CMB and 53% by PMF in Denver. Estimates of the fractional contribution to potential ozone and ozone-linked mortality from O&NG activities are smaller while those from vehicles are larger than the NMHC contributions. CMB (PMF) indicate that greater than 78% (40%) of annual average benzene in Denver is attributable to vehicle emissions while greater than 75% (67%) of benzene in Platteville is attributable to O&NG activities.The Community Multiscale Air Quality (CMAQ) model calculates the impact of emissions on atmospheric composition, including inorganic aerosols, while considering the transport and reactions of chemical constituents. Adjusting emissions by comparing modeled concentrations with observations is justified when the science processes are well understood as is the case for inorganic species such as ammonia (NH3). The Finite Difference Mass Balance (FDMB) method and four-dimensional variational (4D-Var) data assimilation leverage differences in simulated and actual observations to revise estimates of emissions with spatial specificity. In this study, we evaluate the capability of a CMAQ-based data assimilation system to improve NH3 emissions, which are relatively uncertain given the diversity of emissions processes in the agricultural sector. To do so, the iterative FDMB and a Python-based four-dimensional variational framework (Py4Dvar) are integrated with CMAQ and its adjoint to constrain NH3 emissions with observations from the satellite-based Cross-track Infrared Sounder (CrIS). Observing System Simulation Experiments (OSSEs) are conducted with the CrIS observation operator to evaluate the extent to which emissions are expected to be recovered with the hybrid assimilation framework. The OSSEs conducted with the 2007 modeling platform and 2016 CrIS data on a regional domain in Georgia and the OSSEs conducted with the 2017 modeling platform and 2017 CrIS data on the continental U.S. domain result in promising recovery of the true emissions.
Download or read book Towards an Integrated Assessment Model for Tropospheric Ozone Emission Inventories Scenarios and Emission control Options written by Xander Olsthoorn and published by . This book was released on with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sensitivity of Simulated Tropospheric Ozone in the Mid Atlantic Region in June 2016 Using the WRF Chem Model written by Andrew Thomas and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Numerical predictions of tropospheric ozone, a secondary pollutant harmful to human health, contain large sources of uncertainty. Various studies have been conducted on the influence of meteorological initial and boundary conditions, PBL scheme, and emissions inventory, but there is no published comparative study. To address this need, we ran seven simulations of WRF-Chem, a regional online atmospheric chemistry model, with different emissions inventories, PBL parameterizations, and emissions inventories over the eastern United States within the Mid-Atlantic region. The simulations were run for June 2016, which had multiple occurrences of high mixing ratios of observed ozone within the Mid-Atlantic region, particularly along the urbanized Interstate-95 Corridor. Special attention was paid to the 20% of days with the highest observed ozone. Our analysis of the average standard deviation of 8-hour average ozone showed that ground-level ozone was most sensitive to the uncertainty in the initial and boundary conditions, with peaks in average standard deviation of 6 to 7 ppbv, while the emissions inventory uncertainty was of secondary importance with peaks in the average standard deviation of 4 to 5 ppbv. We compared the temporal average of the ensemble members and showed that the emissions inventory has the greatest influence on the average ozone mixing ratio. The ERA-interim generated more ozone than the other initial and boundary conditions ensembles, with ground-level peaks of 70 to 75 ppbv 8-hour averaged ozone. In comparison to the emissions inventory and the meteorological initial and boundary conditions, tropospheric ozone was less sensitive to the PBL scheme. The modeled sensitivity was enhanced aloft over Interstate 95, a source of ozone precursor emissions from mobile sources. Based on our data, we estimated that updating the emissions inventory yields an average decrease of 0.6 ppbv yr-1 in the mean absolute error, and an average decrease of 0.8 ppbv yr-1 in mean daily eight-hour ozone. There are many avenues for further research, including expanding the ensemble size. Our results suggest that the choice of initial and boundary conditions may affect other air quality studies.
Download or read book A Procedures for the Preparation of Emission Inventories for Carbon Monoxide and Precursors of Ozone Emission Inventory Requirements for Photochemical written by U. S. Environmental Protection Agency and published by BiblioGov. This book was released on 2013-07 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt: The U.S. Environmental Protection Agency (EPA) was introduced on December 2, 1970 by President Richard Nixon. The agency is charged with protecting human health and the environment, by writing and enforcing regulations based on laws passed by Congress. The EPA's struggle to protect health and the environment is seen through each of its official publications. These publications outline new policies, detail problems with enforcing laws, document the need for new legislation, and describe new tactics to use to solve these issues. This collection of publications ranges from historic documents to reports released in the new millennium, and features works like: Bicycle for a Better Environment, Health Effects of Increasing Sulfur Oxides Emissions Draft, and Women and Environmental Health.
