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Integrated Assessment of Black Carbon and Tropospheric Ozone

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... The tropospheric ozone (lifetime ~12 years) increases global warming. Ozone is not an emitted as such, while it is formed by the precursor emissions of CO, VOCs, and NO x (Akimoto et al. 2011). ...
Technical Report
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Emission measurement methods have been developed for vehicles using traditional fuels, and they do not necessarily suit, or are not sufficient, for alternative fuels and technologies. New fuels, engines and emission control devices may lead to alterations in the exhaust gas composition, and to the formation of new emission species. Due to the tight emission regulations, emissions have decreased and their quantitative analysis has become more challenging. Therefore, in addition to improving and developing of the traditional analysis methods, it has also become essential to find new comprehensive analysis methods and principles to evaluate for exhaust gas emissions. The aim of this project was to review, improve, develop, and validate emission measurement methods for more comprehensive characterization and impact assessment of the exhaust gas emissions from low-emitting cars and vehicles using alternative fuels. For example, a new comprehensive method for the estimation of oxidative potential in particulate matter and the semivolatile organic samples was introduced (DTT assay), as well as, microAmes test for mutagenicity. Exhaust volume based dosing was developed instead of mass based dosing to enable testing of low-emitting cars with reasonable number of replicate tests. The methods were validated in the measurement campaign. New information was collected, and new methods and tests will be used in the future projects. Preface Emission measurement methods have been developed for traditional vehicles and fuels, and they are not necessarily compatible with new vehicles and alternative fuels. Alternative fuels and new engine and emission control technologies can lead to alterations in the exhaust gas composition and to the possible formation of the new emission species. Chemical characterization of all individual compounds of exhaust gas is not possible using reasonable set of instruments. In addition, quantitative analysis of emissions is challenging for modern low-emitting cars and vehicles, and some exhaust species may be toxic or mutagenic at concentrations below detection limits. As a consequence, comprehensive analysis methods are needed in addition to improved traditional analysis methods. The aim of this project was to review, improve, develop, and validate the emission measurement methods for more comprehensive characterization and impact assessment of the exhaust gas emissions. Existing methods were reviewed and improved to take into account alternative fuels and new engines and emission control technologies. For example, many methods for gaseous emissions were updated and collection method for the semivolatile organic fraction of the exhaust gas was developed. A microAmes test was introduced for small sample sizes and a new comprehensive method for the estimation of oxidative potential in PM and semivolatile samples. New approach basing on exhaust volume instead of particulate mass was introduced for dosing of samples from low emitting cars and vehicles. Methods to characterize exhaust gases from alternative fueled cars and vehicles were validated in an extensive measurement campaign with Euro 6 diesel, E10 E85, and CNG fueled cars and with Euro 2 diesel car. Several methods were also validated in the IEA AMF Annex 44 " Unregulated Pollutants Emissions of Vehicles Fuelled with Alcohol Alternative
... Local environmental impacts arise from damages to ambient air and local forest ecosystems . Because only a fraction of the IAP is deposited indoors, biomass burning contributes to ambient air pollution (Shindell et al. 2011). Additionally, the unsustainable harvest of fuelwood degrades local forests (Hofstad et al. 2009; Köhlin et al. 2011), sometimes even damaging wildlife habitat and watershed functions and contributing to deforestation (Geist and Lambin 2001). ...
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Chapter
Air pollution has large impacts on the Hindu Kush Himalaya (HKH), affecting not just the health of people and ecosystems, but also climate, the cryosphere, monsoon patterns, water availability, agriculture, and incomes (established but incomplete). Although the available data are not comprehensive, they clearly show that the HKH receives significant amounts of air pollution from within and outside of the region, including the Indo-Gangetic Plain (IGP), a region where many rural areas are severely polluted. In addition, the HKH receives trans-boundary pollution from other parts of Asia. This chapter surveys the evidence on regional air pollution and considers options for reducing it, while underlining the need for regional collaboration in mitigation efforts. As described in Chap. 1, the HKH region is fragile and rapidly changing; while the outcome of the interplay of complex drivers is difficult to predict, it will have major consequences. That holds true for air pollution as well.
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The literature on atmospheric particulate matter (PM), or atmospheric aerosol, has increased enormously over the last 2 decades and amounts now to some 1500–2000 papers per year in the refereed literature. This is in part due to the enormous advances in measurement technologies, which have allowed for an increasingly accurate understanding of the chemical composition and of the physical properties of atmospheric particles and of their processes in the atmosphere. The growing scientific interest in atmospheric aerosol particles is due to their high importance for environmental policy. In fact, particulate matter constitutes one of the most challenging problems both for air quality and for climate change policies. In this context, this paper reviews the most recent results within the atmospheric aerosol sciences and the policy needs, which have driven much of the increase in monitoring and mechanistic research over the last 2 decades. The synthesis reveals many new processes and developments in the science underpinning climate–aerosol interactions and effects of PM on human health and the environment. However, while airborne particulate matter is responsible for globally important influences on premature human mortality, we still do not know the relative importance of the different chemical components of PM for these effects. Likewise, the magnitude of the overall effects of PM on climate remains highly uncertain. Despite the uncertainty there are many things that could be done to mitigate local and global problems of atmospheric PM. Recent analyses have shown that reducing black carbon (BC) emissions, using known control measures, would reduce global warming and delay the time when anthropogenic effects on global temperature would exceed 2 °C. Likewise, cost-effective control measures on ammonia, an important agricultural precursor gas for secondary inorganic aerosols (SIA), would reduce regional eutrophication and PM concentrations in large areas of Europe, China and the USA. Thus, there is much that could be done to reduce the effects of atmospheric PM on the climate and the health of the environment and the human population. A prioritized list of actions to mitigate the full range of effects of PM is currently undeliverable due to shortcomings in the knowledge of aerosol science; among the shortcomings, the roles of PM in global climate and the relative roles of different PM precursor sources and their response to climate and land use change over the remaining decades of this century are prominent. In any case, the evidence from this paper strongly advocates for an integrated approach to air quality and climate policies.
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