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Regional and Local Hydrologic Responses to Climate Fluctuations and Land Use Change, Columbia River Basin, WashingtonDuncan, Leslie Lyons 14 April 2017 (has links)
There is evidence that landslides occurred along the White Bluffs in south-central Washington State both within the last 11,000 years and the last several hundred years. Modern, active landslide activity along the bluffs began in the late 1960s. Over the last century, this area of the Columbia River Basin has been converted from rangeland and dryland farming to irrigated agriculture, with water provided to the area via an extensive network of canals and laterals. The most prominent and controversial landslide along the White Bluffs lies above Locke Island. Movement of the slide into the Columbia River has forced the river to shift its flow, eroding the banks of Locke Island and its cultural resources. Water is often implicated as a cause of slope failure. Of particular relevance to understanding the hydrological context for initial failure and longer-term stability of Locke Island landslide are the subsurface recharge and groundwater fluxes at the landslide toe. The influences of land use change and climate fluctuations on the subsurface system, and the relative importance of these factors, has been examined using statistical analysis and a numerical modeling framework. Results from wavelet analysis of an approximately 2000 year Palmer Drought Severity Index dataset indicate that low frequency drought and pluvial cycles, at multidecadal to centennial timescales, are persistent features of regional climate in the Columbia River Basin, which may be linked to solar insolation. Results from a two-dimensional variably saturated finite element model indicate that discharge at the toe of Locke Island landslide is governed by changes to the regional groundwater system. Increases in recharge from irrigation and from a wetter climate can increase regional groundwater flow by raising water levels and increasing the discharge rate from the system. Large fluctuations in river stage can increase discharge at the landslide toe more than regional increases in recharge; these increases, however, tend to be short-lived. Regional recharge to the groundwater system is likely the largest influence on achieving and maintaining a state of equilibrium along the White Bluffs.
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Edge of Town: Cultivating a Critical Design Discourse in the Liberal ArtsChua, Dominique 01 January 2017 (has links)
As theoretical and practical explorations of design in the past century have broadened to integrate myriad disciplines, its ubiquity and pertinence across diverse ways of knowing grows more apparent and complex. However, in education, design often remains institutionally and intellectually contained to pre-professional programs and trade schools. I contend in this thesis that liberal arts campuses warrant their own critical design-oriented discourse. As a tangible way of addressing this assertion, I coordinated the publishing of a printed design magazine entitled Edge of Town. To support my rationale for my project I present in this written supplement a set of academic literature demonstrating how current political and economic forces shaping design practice justifies a critical evaluation of the discipline. I also illustrate how the growing body of research between rhetoric and design provides a theoretical template for this re-evaluation of contemporary design practice. In the second half, I outline the components of Edge of Town and how the community that worked to produce it came together.
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A Comparison of the Environment, Health, And Safety Characteristics of Advanced Thorium-Uranium and Uranium-Plutonium Fuel CyclesAult, Timothy Mason 01 March 2017 (has links)
The environment, health, and safety properties of thorium-uranium-based (âthoriumâ) fuel cycles are estimated and compared to those of analogous uranium-plutonium-based (âuraniumâ) fuel cycle options using a structured assessment methodology. Thorium resource recovery as a measure of environmental sustainability is described in terms of resource availability, chemical processing requirements, and radiological impacts. Results indicate that near-term thorium recovery will occur as a by-product of mining for other commodities, particularly titanium, and could satisfy even the most intensive nuclear demand for thorium six times over. Chemical flowsheet and radiological process analyses show greater, but not insurmountable, impacts for thorium recovery compared to uranium recovery. Four fuel cycle options are compared: a modified-open uranium option, a modified-open thorium option, a closed uranium option, and a closed thorium option. The options are compared on the bases of resource sustainability, waste management (both low- and high-level waste), and occupational radiological impacts. At steady-state, occupational doses somewhat favor the closed thorium option while low-level waste slightly favors the closed uranium option, although uncertainties are significant. The high-level waste properties favor the closed options (especially with thorium), but uranium options produce slightly less I-129 and may present less risk in a repository environment. Resource requirements are much lower for the closed options and are relatively similar between thorium and uranium. In addition to the steady-state results, several potential transition pathways are considered for closed uranium and thorium end-states. For dose, low-level waste, and fission products contributing to repository risk, the differences among transition impacts largely reflect the steady-state differences. However, the high-level waste properties show the opposite result in transition (strongly favoring uranium, whereas thorium is strongly favored at steady-state), since used present-day uranium fuel is disposed in transitions to purely thorium-based options. Resource consumption was the only metric was strongly influenced by specific transition pathways, favoring the most rapid transitions regardless of whether thorium or uranium was used.
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Three essays on decomposition analysis of the territorial CO 2 emissions and the emissions embodiment in trade attributable to consumption of service-oriented economiesChoesawan, Chairat 19 October 2016 (has links)
<p> With the pace of globalization, the rapid growth in international trade has led to a widespread perception of increasing CO<sub>2</sub> embodied emissions. As the fragmentation of international production has become a dominant feature of modern international trade, there is a vibrant debate over how embodied emissions should be attributed and allocated among economies. To contribute to the debate on emission allocations and mitigation effort comparisons, it is important to consistently investigate the structures of carbon transfers across global economies. The role of carbon transfer structures in affecting mitigation efforts can be explored as part of the consequences of various emission allocations. Thus, it becomes a fundamental theme of all three essays. Due to the leading economies in international trade in terms of volume and CO<sub>2</sub>, extensive attention of this dissertation has been paid to the United States (U.S.), China, and European Union (EU) economies.</p><p> Emissions due to U.S. imports grew increasingly and contributed 31% of the worldwide imported emissions in 2012. Undoubtedly, taking emission responsibility for U.S. imports is important to gear up for a low carbon future. To integrate U.S. imports into the responsibility of global emissions, it is important to investigate the U.S. import effects and identify contributing factors behind imported emission changes. Two aspects are of interest for an understanding of imported emissions and the structure of carbon transfers: (1) the U.S. import demand can affect not only embodied emissions but also emissions at home; and (2) the sector coverage can determine the results of contributing factors. In this respect, the first essay entitled “Two-Stage Index Decomposition Analyses of Domestic and Import Related CO<sub>2</sub> Emission Changes for the U.S. Economy” utilizes a modification of multi-period logarithmic mean divisia index (LMDI II) to perform decomposition analyses of the import effects on both emissions for the U.S. economy during the period 1991-2012. It further employs an attribution technique of LMDI II in order to explore emission contributions of four industrial sectors (the utility, primary, secondary, and tertiary sectors). Dynamic changes in imported emissions are decomposed into five consumption factors: emission coefficient; energy intensity; structure of imports; final import composition; and final import scale. Dynamic changes in production emissions are generated based on three production factors of aggregate and disaggregated (real) carbon intensities: emission coefficient; energy intensity; and structure. The main findings of this essay are presented in page 9. Analysis of the interplay of the contributing factors behind changes in emissions stimulated due to both import demand and domestic production become more critical for having a better understanding of the structure of carbon transfers. Also, it becomes important for seeking policy recommendations on emission responsibilities across economies as part of a transition to a low carbon future. </p><p> Global production fragmentation significantly affects the allocation of emissions embodied in international trade. Thus, differences between production-based emissions (PBE) and consumption-based emissions (CBE) increasingly produce uneven policy actions for targeting emission reductions between exporting and importing economies. These differences may impact mitigation efforts across economies given the current level of carbon transfers. As an alternative, a sharing-based emissions (SE) allocation is an approach that assigns exporters and importers responsibility for emissions based upon benefits linked to their production and consumption. The challenge facing the application of SE allocation is how to define a weighing procedure. In light of embodied emissions in international trade, Peters (2008) suggested that value-added should be used to define a weighting framework. However, no defined weighting procedure has been addressed so far in the literature. The second essay entitled “Sharing-Based CO<sub> 2</sub> Emission Allocation with a Perspective on a Multilateral Border Tax Adjustment-the U.S. Economy” first aims to design a weighting procedure for establishing shares of the emission allocation.</p><p> Due to uneven distributions between emission and global trade intensities across economies, a change in emission allocations from the current PBE approach to an alternative approach that considers both production and consumption can result in a significant emission responsibility burden for specific industries. Thus, an impact evaluation is important to explore mitigation efforts and define the consequences of alternative emission allocations. To identify allocations, the applications of alternative allocations are empirically applied to the U.S. economy for the years 2005 and 2011. These alternative allocation are the SE and the consumption allocation with the application of a unilateral border tax adjustment. The main findings of this essay are presented in page 57. (Abstract shortened by ProQuest.)</p>
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An analysis of performance criteria of porous ceramic water filter production methodsScannell, Luke Weber 25 October 2016 (has links)
<p> The World Health Organization estimated in 2013 that 768 million people lack access to improved drinking water sources. Ceramic water filters have grown in popularity over the past several decades as a point-of-use treatment option to improve water quality. Water treatment reduces the health risks from disease from microbial pollution and potentially other causes. To improve filter design, a more thorough analysis is needed of the effects of the clay and organic materials used to make ceramic water filters. The research presented in this dissertation investigates the effect of four variables on ceramic water filter performance: type of organic matter, total percent volatile matter, air drying compared to oven drying at 105°C, and organic matter particle size. Ceramic water filters were made using the two most common material compositions, clay and sawdust, and clay and rice husks. The moisture content, volatile matter content, and ash content of each material was measured. Ceramic discs 7.6 cm in diameter were made and fired to test for flow rate, porosity, and microbial removal efficiency. Ceramic bars were tested for flexural and impact strength. </p><p> Flow rate increased with increasing volatile matter, and therefore with porosity. The Carman-Kozeny equation was fitted to sawdust and rice husk flow rate data with an <i>R</i><sup>2</sup> value of 0.414 and 0.970 respectively. Oven drying filters resulted in a 0.80 to 1.8 log decrease in bacterial removal. Filters produced with a mixture of 75% large (0.297–0.841 mm) and 25% small (<0.297 mm) organic particles demonstrated a 68% increase in flow rate without reduction in microbial removal compared to filters made with 100% large particles. Microbial removal efficiency decreased with increasing volatile matter content, porosity, and organic matter particle diameter. The flexural and impact strength of sawdust specimens decreased with increasing volatile matter content. Flexural strength of rice husk specimens decreased with increasing volatile matter. However, impact strength of rice husk specimens increased with increasing volatile matter. The model by Li and Aubertin (2003) was fitted to sawdust and rice husk flexural strength data with an <i>R</i><sup>2</sup> value of 0.925 and 0.935, respectively.</p><p> The results presented in this dissertation provide a range of flow rate and porosity values for sawdust and rice husk filters that can be used to predict the expected microbial removal efficiency. They compose a system of standard methods to test ceramic water filters that will allow for accurate comparison of filters made with different materials and methods.</p>
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Surface Ozone, Extreme Air Quality Episodes, and Heat Waves| New Applications for Chemistry-Climate ModelsSchnell, Jordan Lee 27 October 2016 (has links)
<p> Global change is driving chemistry, climate, and atmospheric composition to new regimes over the coming century, threatening attainment of air quality standards globally. The models used to quantify future air quality changes are often plagued with large surface ozone biases, hindering efforts to directly compare models with observations and to accurately quantify future changes. Studies of air quality extremes often rely on point-based measurements and an absolute threshold exceedance; consequently, they neither capture the large-scale, spatially coherent structures of the worst pollution episodes nor compare directly with models’ grid cell averages. This dissertation develops novel statistical approaches to commensurately compare observations and models with a specific focus on extreme pollution episodes.</p><p> The first of four studies led by the doctoral candidate develops a generalizable interpolation algorithm that converts irregularly spaced ozone measurements from surface networks in North America and Europe into maps of grid cell averaged ozone, allowing direct comparison with a global model. Air quality extreme (AQX) events are defined locally as statistical extremes of the ozone climatology and are found to predominantly occur in clustered, coherent, multiday episodes with spatial extents of more than 1,000 km. Additionally, the University of California, Irvine Chemistry Transport Model (UCI CTM) demonstrates skill in hindcasting the observed extreme episodes, thus identifying a new diagnostic to test global chemistry-climate models. The second study evaluates the ability of the UCI CTM and a suite of models from the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP) to simulate the observed, present-day surface ozone climatology over North America and Europe. The tests span temporal scales from diurnal to multi-year variability and on statistics from median geographic patterns to the timing and size of AQX episodes. We also identified and corrected an error in the UCI CTM diurnal cycle. The third study uses the ACCMIP models to quantify the effect of future climate change on surface ozone. The fourth study extends the methods to characterize the co-occurrence of surface ozone, particulate matter, and temperature extremes, providing further diagnostics for model evaluation and enabling an investigation of the multi-stressor impacts of poor air quality and heat waves.</p>
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Passive Acoustics: A Multifaceted Tool for Marine Mammal ConservationPhillips, Goldie January 2016 (has links)
<p>Marine mammals exploit the efficiency of sound propagation in the marine environment for essential activities like communication and navigation. For this reason, passive acoustics has particularly high potential for marine mammal studies, especially those aimed at population management and conservation. Despite the rapid realization of this potential through a growing number of studies, much crucial information remains unknown or poorly understood. This research attempts to address two key knowledge gaps, using the well-studied bottlenose dolphin (Tursiops truncatus) as a model species, and underwater acoustic recordings collected on four fixed autonomous sensors deployed at multiple locations in Sarasota Bay, Florida, between September 2012 and August 2013. Underwater noise can hinder dolphin communication. The ability of these animals to overcome this obstacle was examined using recorded noise and dolphin whistles. I found that bottlenose dolphins are able to compensate for increased noise in their environment using a wide range of strategies employed in a singular fashion or in various combinations, depending on the frequency content of the noise, noise source, and time of day. These strategies include modifying whistle frequency characteristics, increasing whistle duration, and increasing whistle redundancy. Recordings were also used to evaluate the performance of six recently developed passive acoustic abundance estimation methods, by comparing their results to the true abundance of animals, obtained via a census conducted within the same area and time period. The methods employed were broadly divided into two categories – those involving direct counts of animals, and those involving counts of cues (signature whistles). The animal-based methods were traditional capture-recapture, spatially explicit capture-recapture (SECR), and an approach that blends the “snapshot” method and mark-recapture distance sampling, referred to here as (SMRDS). The cue-based methods were conventional distance sampling (CDS), an acoustic modeling approach involving the use of the passive sonar equation, and SECR. In the latter approach, detection probability was modelled as a function of sound transmission loss, rather than the Euclidean distance typically used. Of these methods, while SMRDS produced the most accurate estimate, SECR demonstrated the greatest potential for broad applicability to other species and locations, with minimal to no auxiliary data, such as distance from sound source to detector(s), which is often difficult to obtain. This was especially true when this method was compared to traditional capture-recapture results, which greatly underestimated abundance, despite attempts to account for major unmodelled heterogeneity. Furthermore, the incorporation of non-Euclidean distance significantly improved model accuracy. The acoustic modelling approach performed similarly to CDS, but both methods also strongly underestimated abundance. In particular, CDS proved to be inefficient. This approach requires at least 3 sensors for localization at a single point. It was also difficult to obtain accurate distances, and the sample size was greatly reduced by the failure to detect some whistles on all three recorders. As a result, this approach is not recommended for marine mammal abundance estimation when few recorders are available, or in high sound attenuation environments with relatively low sample sizes. It is hoped that these results lead to more informed management decisions, and therefore, more effective species conservation.</p> / Dissertation
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Bridging the Scale Gap from Leaf to Canopy in Biosphere-Atmosphere Gas and Particle ExchangesHuang, Cheng-Wei January 2016 (has links)
<p>Terrestrial ecosystems, occupying more than 25% of the Earth's surface, can serve as</p><p>`biological valves' in regulating the anthropogenic emissions of atmospheric aerosol</p><p>particles and greenhouse gases (GHGs) as responses to their surrounding environments.</p><p>While the signicance of quantifying the exchange rates of GHGs and atmospheric</p><p>aerosol particles between the terrestrial biosphere and the atmosphere is</p><p>hardly questioned in many scientic elds, the progress in improving model predictability,</p><p>data interpretation or the combination of the two remains impeded by</p><p>the lack of precise framework elucidating their dynamic transport processes over a</p><p>wide range of spatiotemporal scales. The diculty in developing prognostic modeling</p><p>tools to quantify the source or sink strength of these atmospheric substances</p><p>can be further magnied by the fact that the climate system is also sensitive to the</p><p>feedback from terrestrial ecosystems forming the so-called `feedback cycle'. Hence,</p><p>the emergent need is to reduce uncertainties when assessing this complex and dynamic</p><p>feedback cycle that is necessary to support the decisions of mitigation and</p><p>adaptation policies associated with human activities (e.g., anthropogenic emission</p><p>controls and land use managements) under current and future climate regimes.</p><p>With the goal to improve the predictions for the biosphere-atmosphere exchange</p><p>of biologically active gases and atmospheric aerosol particles, the main focus of this</p><p>dissertation is on revising and up-scaling the biotic and abiotic transport processes</p><p>from leaf to canopy scales. The validity of previous modeling studies in determining</p><p>iv</p><p>the exchange rate of gases and particles is evaluated with detailed descriptions of their</p><p>limitations. Mechanistic-based modeling approaches along with empirical studies</p><p>across dierent scales are employed to rene the mathematical descriptions of surface</p><p>conductance responsible for gas and particle exchanges as commonly adopted by all</p><p>operational models. Specically, how variation in horizontal leaf area density within</p><p>the vegetated medium, leaf size and leaf microroughness impact the aerodynamic attributes</p><p>and thereby the ultrane particle collection eciency at the leaf/branch scale</p><p>is explored using wind tunnel experiments with interpretations by a porous media</p><p>model and a scaling analysis. A multi-layered and size-resolved second-order closure</p><p>model combined with particle </p><p>uxes and concentration measurements within and</p><p>above a forest is used to explore the particle transport processes within the canopy</p><p>sub-layer and the partitioning of particle deposition onto canopy medium and forest</p><p>oor. For gases, a modeling framework accounting for the leaf-level boundary layer</p><p>eects on the stomatal pathway for gas exchange is proposed and combined with sap</p><p>ux measurements in a wind tunnel to assess how leaf-level transpiration varies with</p><p>increasing wind speed. How exogenous environmental conditions and endogenous</p><p>soil-root-stem-leaf hydraulic and eco-physiological properties impact the above- and</p><p>below-ground water dynamics in the soil-plant system and shape plant responses</p><p>to droughts is assessed by a porous media model that accommodates the transient</p><p>water </p><p>ow within the plant vascular system and is coupled with the aforementioned</p><p>leaf-level gas exchange model and soil-root interaction model. It should be noted</p><p>that tackling all aspects of potential issues causing uncertainties in forecasting the</p><p>feedback cycle between terrestrial ecosystem and the climate is unrealistic in a single</p><p>dissertation but further research questions and opportunities based on the foundation</p><p>derived from this dissertation are also brie</p><p>y discussed.</p> / Dissertation
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On the Regulation of Small Actors: Three Experimental Essays about Policies based on Voluntary Compliance and Decentralized MonitoringRodriguez Ramirez, Luz Angela January 2016 (has links)
<p>Monitoring and enforcement are perhaps the biggest challenges in the design and implementation of environmental policies in developing countries where the actions of many small informal actors cause significant impacts on the ecosystem services and where the transaction costs for the state to regulate them could be enormous. This dissertation studies the potential of innovative institutions based on decentralized coordination and enforcement to induce better environmental outcomes. Such policies have in common that the state plays the role of providing the incentives for organization but the process of compliance happens through decentralized agreements, trust building, signaling and monitoring. I draw from the literatures in collective action, common-pool resources, game-theory and non-point source pollution to develop the instruments proposed here. To test the different conditions in which such policies could be implemented I designed two field-experiments that I conducted with small-scale gold miners in the Colombian Pacific and with users and providers of ecosystem services in the states of Veracruz, Quintana Roo and Yucatan in Mexico. This dissertation is organized in three essays. </p><p>The first essay, “Collective Incentives for Cleaner Small-Scale Gold Mining on the Frontier: Experimental Tests of Compliance with Group Incentives given Limited State Monitoring”, examines whether collective incentives, i.e. incentives provided to a group conditional on collective compliance, could “outsource” the required local monitoring, i.e. induce group interactions that extend the reach of the state that can observe only aggregate consequences in the context of small-scale gold mining. I employed a framed field-lab experiment in which the miners make decisions regarding mining intensity. The state sets a collective target for an environmental outcome, verifies compliance and provides a group reward for compliance which is split equally among members. Since the target set by the state transforms the situation into a coordination game, outcomes depend on expectations of what others will do. I conducted this experiment with 640 participants in a mining region of the Colombian Pacific and I examine different levels of policy severity and their ordering. The findings of the experiment suggest that such instruments can induce compliance but this regulation involves tradeoffs. For most severe targets – with rewards just above costs – raise gains if successful but can collapse rapidly and completely. In terms of group interactions, better outcomes are found when severity initially is lower suggesting learning. </p><p>The second essay, “Collective Compliance can be Efficient and Inequitable: Impacts of Leaders among Small-Scale Gold Miners in Colombia”, explores the channels through which communication help groups to coordinate in presence of collective incentives and whether the reached solutions are equitable or not. Also in the context of small-scale gold mining in the Colombian Pacific, I test the effect of communication in compliance with a collective environmental target. The results suggest that communication, as expected, helps to solve coordination challenges but still some groups reach agreements involving unequal outcomes. By examining the agreements that took place in each group, I observe that the main coordination mechanism was the presence of leaders that help other group members to clarify the situation. Interestingly, leaders not only helped groups to reach efficiency but also played a key role in equity by defining how the costs of compliance would be distributed among group members. </p><p>The third essay, “Creating Local PES Institutions and Increasing Impacts of PES in Mexico: A real-Time Watershed-Level Framed Field Experiment on Coordination and Conditionality”, considers the creation of a local payments for ecosystem services (PES) mechanism as an assurance game that requires the coordination between two groups of participants: upstream and downstream. Based on this assurance interaction, I explore the effect of allowing peer-sanctions on upstream behavior in the functioning of the mechanism. This field-lab experiment was implemented in three real cases of the Mexican Fondos Concurrentes (matching funds) program in the states of Veracruz, Quintana Roo and Yucatan, where 240 real users and 240 real providers of hydrological services were recruited and interacted with each other in real time. The experimental results suggest that initial trust-game behaviors align with participants’ perceptions and predicts baseline giving in assurance game. For upstream providers, i.e. those who get sanctioned, the threat and the use of sanctions increase contributions. Downstream users contribute less when offered the option to sanction – as if that option signal an uncooperative upstream – then the contributions rise in line with the complementarity in payments of the assurance game.</p> / Dissertation
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A STUDY OF AEROSOL ACIDITY OVER THE NORTHEASTERN UNITED STATESUnknown Date (has links)
Ambient sulfate aerosols are composed of sulfuric acid, ammonium sulfate, or other sulfate salt mixtures, and the term "total sulfate" includes these substances of diverse chemical and physical properties. Measurements of total sulfate are often made, but without measurements of the associated cations they are inadequate to assess the contribution of aerosols to acid rain, damage to surfaces, heterogeneous oxidation of SO(,2), and human health effects. In this study the chemical properties of sulfate aerosols were investigated in the northeastern U.S. by measurements of acidity, ionic composition, and particle morphology over a range of conditions. / Aerosols were collected from an aircraft during three field programs: spring and fall 1979 and summer 1980. Strong and weak aerosol acidity was determined by extraction of filters and Gran titrations, and for 30 samples the weak acidity comprised x (+OR-) s = 26 (+OR-) 12% of the total acidity. The strong acid and ammonium concentrations were found to balance the sulfate with the ratio of equivalents ({H('+)} + {NH(,4)('+)})/{SO(,4)('=)} = 1.03 (+OR-) 0.14 for 36 samples. The strong acidity averaged 25 (+OR-) 18% of the total sulfate. A phase diagram was used to show that the aerosols were often liquid at ambient humidity, and for 24 liquid samples the calculated pH was 0.11 (+OR-) 0.59. / Inspecting particles by electron microscopy showed that under most conditions accumulation mode aerosols collected in the boundary layer were composed of sulfate particles which were internally mixed, indicating that individual particle composition could be inferred from bulk measurements. Evidence for oxidation of SO(,2) to H(,2)SO(,4) in cloud droplets was obtained in samples collected near clouds, representing a potentially major pathway for SO(,2) oxidation in the lower troposphere. / Elemental size distributions determined by cascade impactors and x-ray analysis showed distinct seasonal differences. While sulfate concentrations averaged 16.7 (+OR-) 9.9 (mu)g/m('3) in summer and 6.68 (+OR-) 3.27 in fall, chlorine concentrations were much higher in fall suggesting loss of HCl from the more acidic summertime aerosols. The sulfur size distributions showed that summer particles contained twice the mass per particle as those during fall, indicating a possible enhancement of sulfate in aerosol droplets by a liquid-phase SO(,2) oxidation mechanism. / Source: Dissertation Abstracts International, Volume: 43-01, Section: B, page: 0081. / Thesis (Ph.D.)--The Florida State University, 1982.
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