Pollution, extreme weather, and global warming have become increasingly important in today’s society. This dissertation examines these topics in three chapters, analyzing the effects of pollution and environmental factors on human behavior. The first chapter uses a dataset of unique daily crimes in the U.S. to unveil the relationship between weather/pollution and the crime rate for seven major U.S. cities. The results reveal that temperature significantly affects both violent and property crime rates. The rate of violent crime is lower on extreme and unpleasant weather days (i.e., when the temperature is above 99°F) in comparison to good or unremarkable days. There is little evidence on how air pollution affects the crime rate by using fine particulates (PM2.5) and coarse particulates (PM10). However, pollution does have an effect on crime if the area of analysis is located closer to an operated toxic release facility. The second chapter examines how weekly hours worked by individuals vary with respect to snowfall in 265 metropolitan areas (about 75% of the US workforce) over the years 2004-2014. The results reveal that working hours are significantly affected by snow events, with magnitudes varying by types of workers, types of employment (class of worker, occupation, and industry), and regions. Overall, each average daily inch of snowfall, during a Current Population Survey (CPS) monthly reference week, reduces working hours by about 1 hour. Snow storms reduce weekly hours worked considerably more among construction workers and in the South than elsewhere in the U.S.. We find little evidence that hours lost from large snowfalls are “made-up” in subsequent weeks. The third chapter investigates whether housing age, which has been missing in the conventional environmental justice literature, has an impact on the distribution of households in a pollution area. Income and race were believed to be predominant factors that affect the location choices of individuals. By controlling for this additional housing age variable in the conventional model, I examine which factor, income or race, is affected most. The results indicate that older houses are located closer to pollution sites. Additionally, once I control for the housing age, the marginal effect of income declines significantly, approximately by 50%. The effect on race was insignificant in empirical analysis.

This thesis is concerned with layered reflections observed in the Antarctic and Greenland ice sheets during radio-echo sounding. It describes in detail layering seen with 60 and 300 MHz equipment _in the Antarctic ice sheet during three field seasons betwe~n 1974 and 1979, and discusses the effects of glaciological and equipment factors, particularly radio pulse length. The effects of changing pulse length and accumulation rate on layer echo separation are analysed, and the importance of closely spaced groups of reflectors assessed. Reflection coefficient vs depth profiles are presented for layering observed at nearly twenty sites in the Antarctic and Greenland, and are used to demonstrate the existence of two separate reflection mechanisms: changes in (a) ice density, and (b) loss tangent. Supporting density and conductivity data from ice cores are summarised. It is concluded that most layer echoes arise from layers of ice containing acidic impurities of volcanic origin~ Layer reflectivity variations_are observed over distances of tens of kilometres. Short-period fading is also observed, from which estimates of layer reflector roughness are made using the autocorrelation function and variance of the received power. The roughness estimates are shown to be consistent with a depositional origin for the surfaces. Relevant theory is summarised and a procedure developed for the remote estimation of elevated acidity levels in ice from radio-echo sounding. Such estimates are shown to compare well with direct ice core measurements. The method is used to present estimated elevated acidity profiles for the Antarctic (to ~100 kaBP) and Greenland (to ~30 kaBP), which are interpreted in terms of variations in the input of volcanogenic acid impurities to the ice sheets. The use of layering as isochronous horizons in ice flow studies is discussed in the light of new measurements, with particular emphasis on t he zone close to bedrock.

Active microwave sensors are known to provide valuable information regarding snow and ice surfaces in the polar regions, where darkness and cloud cover prevail. Here, data collected in the Arctic by a Ku-band microwave radar altimeter, designed and constructed in the UK, are analysed. The two main components of this study comprise data gathered in the East Greenland Sea marginal ice zone and over two Svalbard ice caps. A systematic treatment is made of the electromagnetic properties of snow and ice at 13.81 GHz, and the differences between various polar surface media are highlighted. Theoretical and empirical models are presented which enable calculation of the relevant dielectric and scattering properties of snow and ice layers. Parametric studies are undertaken to give insight into the range of scattering conditions likely to be encountered by a radar altimeter in the regions investigated. Examples of altimetric data and results of their analysis are presented, demonstrating the effects of different ice types and terrain upon incident altimeter pulses. Waveforms are characterised by their shape, and certain forms are linked with particular physical properties of the surface. To this a variety of supporting information is added in order to verify and validate interpretations of these results. Algorithms are proposed which enable geophysical information to be derived from altimetric data.

The growth of the Weddell Sea ice cover in 1980 is examined, using Nimbus-7 satellite Scanning Multi-channel Microwave Radiometer (SMMR) data in combination with data (positional, air temperature and atmospheric pressure) from 4 Nimbus-tracked drifting buoys. Ice concentrations are retrieved from the SMMR data by applying a cluster analysis algorithm developed by J. Comiso of NASA. Analyses of computed differential kinematic parameters (DKP)s of the buoy array offer insight into the complex mesoscale behaviour of the underlying Weddell Gyre. High frequency divergence, convergence and deformation events isolated in the DKP results, and driven largely by the regular passage of cyclones, are related to changes in ice concentration observed in the SMMR data. The profound role of the Antarctic Peninsula in influencing both atmospheric and oceanic circulation (and thus ice formation, drift and eventual decay) in the region is evaluated. Possible relationships between buoy drift in the inner pack and ice edge advance are examined, yielding information on the relative importance of ice growth in open water within the pack and that at the ice edge. After an introductory chapter, Chapter 2 describes the physical setting of the Weddell Sea. Comparisons are drawn both with other sectors of the Southern Ocean and the Arctic, emphasizing the uniqueness of the region not only in terms of its climate and oceanography but also its sea ice cover. Chapter 3 traces the evolution of passive microwave remote sensing from space as a tool for monitoring Antarctic sea ice extent and concentration; the relative merits and disadvantages of these techniques are evaluated. Chapter 4 concentrates on the use of SMMR data. Detailed comparisons are made of algorithms available for the extraction of ice concentrations from the raw brightness temperature data. The choice of algorithm used is justified. Chapter 5 is largely concerned with the analysis of the buoy data, and the kinematic behaviour of the array as a unit. These results are combined with the SMMR data in Chapter 6 to identify distinct dynamic zones and meridional advective sectors, and to compare the behaviour of the inner pack with that of the unconstrained ice edge. The evolution of a high concentration core within the unique perennial sea ice zone hugging the east coast of the Peninsula, which persists throughout the period of study is unusual enough to merit a separate sub-section. Conclusions are drawn in chapter 7.

been used to investigate the form and topography of the Antarctic ice sheet and to relate these to the physical processes of ice flow and basal conditions. Topographic roughness typically increases towards the thin ice of coastal reg ions as surface undulation wav el eng ths decrease and amplitudes increase. Temperature and velocity variations also have significant effects. The coastal zone is punctuated by embayments of severe topography immediately inland of outlet glaciers. This topographic variability has been summarized in a statistical model for the purposes of simulating satellite radar altimeter waveforms. Consideration of the relationship between bedrock and surface profiles has shown that ice temperature is a major influence on the response of the surface to bedrock irregularities. Regional subglacial water layers may al so have an important effect on surface topography. A re-analysis of models of longitudinal stress grad i ents suggests that er ystal fabrics favouring faster flow develop with distance from ice divides and that the relative depth of the zone of maximum shear fluctuates in response to topographic and glaciological constraints. Driving stress patterns have been associated with characteristic glaciological regimes and have suggested a qualitative difference between outlet glaciers and ice streams. The transition to high velocity flow in outlet glaciers has been shown to be triggered ab ruptly in response to subglac ial fjord heads. The dependence of fast flow on subglacial topography indicates a significant stabilizing effect on discharge from ice sheets and suggests that surge behaviour is unlikely within existing ice sheet outlets. The onset of basal sliding at the head of subglac ial fjords suggests a mechanism for the production of overdeepened fjords and steep headwalls through concentrated erosion. This may help in the reconstruction of the dynamics of former ice sheets. Some West Antarctic ice streams do not exhibit this rapid transition in behaviour.

Visual snow syndrome is a persistent visual disturbance characterized by rapid flickering dots in the entire visual field. Hypothesized to arise from reduced inhibition of sensory cortex, visual snow has recently been linked to potentiation (enhancement) of the P100, an event-related potential (ERP) component associated with early visual processing. Here, we investigate whether this potentiation in visual snow is specific to visual responses, by comparing ERPs linked to early, bottom-up perceptual versus late, top-down cognitive processes. Specifically, we examined two components, the N170 and P300, associated respectively with rapid face categorization and attentional orienting towards targets. We predicted that if visual snow predominantly reflects diminished inhibition of perceptual areas, there should be stronger potentiation for the earlier perceptual N170 component. ERPs associated with the N170 (Face > House) and P300 (Target > Nontarget) were recorded in a 22 year-old male with a 2-year history of visual snow symptoms and a set of age- and gender-matched controls. Although N170 and P300 responses in all participants showed appropriate face- and target-selectivity, respectively, the visual snow patient demonstrated consistent potentiation relative to controls, particularly for the early N170 response. Bootstrapped estimates of mean amplitude computed within participants similarly revealed larger and more variable ERP amplitudes in the visual snow patient, especially for the N170 component. These results support an early perceptual locus of ERP potentiation in visual snow, further supporting the idea that this condition arises from diminished inhibition of sensory cortices.

The phenomenon of snow interception by forest stands is examined. Interception relationships extracted from literature are evaluated for their applicability to the silvicultural and climatic conditions of south coastal British Columbia. Hypotheses tested address: 1) the prediction of snow interception, 2) comparisons of heterogeneity in snow interception between second-growth and old-growth forests, and 3) how interception and interception efficiency vary depending on forest crown completeness and storm size. General relationships regarding snow interception under continental conditions were found to hold in coastal conditions', but relationships between crown completeness and interception were weak. Storm size and melt are identified as confounding factors in making predictions about snow interception based on stand crown completeness. Several approaches to modelling snow interception are discussed. Particular reference is made to the effect of interception on energetic costs of locomotion for deer. Management of coastal forests for the interception of snow should focus on maximizing crown completeness and crown surface area. Further research is required concerning the relationships used in the simulation models. Emphasis should be placed on deer response to snowpacks, the influence of melt on snowpack development, and the influence of canopy closure on spatial distribution of snowpacks. / Forestry, Faculty of / Graduate

M.Ing. (Mechanical Engineering) / In snow shooting, pressurised liquid carbon dioxide is injected via a lance into a permeable snow bag mounted near the ceiling of an insulated transport container. The decrease in pressure causes the liquid carbon dioxide to convert to "snow" and vapour inside the snow bag. The snow bag acts as a phase separator, allowing the sublimated snow to cool down the products inside a container. In this thesis the heat transfer coefficients of such a snow bag were determined experimentally and theoretically. It was found, that on average the measured heat transfer coefficient was 31% lower than the theoretical prediction. The theoretical model was used to correlate the experimental heat transfer coefficient as function of snow height. With this correlation it was possible to predict the time of the snow life to within 24%.

Submitted by Isaac Francisco de Souza Dias (isaac.souzadias@ufpe.br) on 2016-04-15T17:03:15Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) TESE Eduardo José Oenning Soares.pdf: 3277476 bytes, checksum: f1780895f42c77c8bd752b7ed386ea18 (MD5) / Made available in DSpace on 2016-04-15T17:03:15Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) TESE Eduardo José Oenning Soares.pdf: 3277476 bytes, checksum: f1780895f42c77c8bd752b7ed386ea18 (MD5) Previous issue date: 2015-09-30 / Muitas críticas são apresentadas na literatura a respeito da implementação do Sistema de Gestão da Qualidade da norma ISO 9001, que focam principalmente no fato de que nem sempre as empresas que buscaram a certificação observaram grandes benefícios após a sua obtenção. Tal fenômeno pode ocorrer pela dificuldade encontrada pelas empresas durante o processo de implementação. Neste contexto, esta pesquisa se propõe a avaliar o grau de dificuldade encontrado pelas empresas, que já implementaram um Sistema de Gestão da Qualidade conforme proposto pela norma ISO 9001:2008, e relacionar esta dificuldade com a tipologia estratégica de Miles e Snow. Fizeram parte da amostra 62 empresas atuantes no Brasil do setor de construção civil para obter dados sobre o perfil estratégico e o grau de dificuldade que essas empresas observaram no processo de implementação da norma. Hipóteses foram formuladas para testar se há uma diferença significativa entre o grau de dificuldade na implementação dos itens dos requisitos da norma e a tipologia estratégica dessas organizações. Como resultado foi possível observar que empresas com diferentes tipos estratégicos apresentaram diferentes níveis de dificuldade no processo de implementação da norma. A partir destes resultados, este estudo propôs uma abordagem para avaliar e auxiliar na implementação dos requisitos da norma ISO 9001:2008, assim, empresas com tipologias estratégicas específicas podem identificar os itens dos requisitos que teriam mais dificuldade em implementar, facilitando as decisões sobre a alocação de recursos, a atribuição de pessoal adequado ou diagnosticar as necessidades de formação e qualificação de pessoal, contribuindo para o planejamento de recursos humanos. Ao final, a aplicabilidade da abordagem proposta foi avaliada em um estudo de caso, no qual foi possível observar que a empresa estudada não possuía condições suficientes de implementar os requisitos da norma por conta própria. Assim, foi proposta, por meio de um método multicritério, a seleção de alternativas da qual incluía a contratação de consultores. Esta alternativa foi bem aceita pela empresa alvo do estudo de caso. / Many criticisms are presented in the literature regarding the implementation of standard ISO 9001. These criticisms focus primarily on the fact that companies that have sought certification have not always encountered benefits after obtaining certification. This phenomenon may occur due to the difficulties encountered by companies during the implementation process. Within this context, this research aims to evaluate the degree of difficulty encountered by companies, which have implemented a Quality Management System as proposed by the ISO 9001: 2008, and relate this difficulty with strategic typology of Miles and Snow. The sample included 62 Brazilian companies in the construction industry to obtain data on the strategic profile and the degree of difficulty these companies have noted in the implementation process of the standard. Hypotheses were formulated to test whether there is a significant difference between the degree of difficulty in the implementation of the items of the standard requirements and the strategic typology of these organizations. As a result it was observed that companies with different strategic types presented different levels of difficulty in the implementation process of the standard. From these results, this study has proposed an approach to measure and assist the implementation of ISO 9001: 2008 requirements so that companies with specific strategic types may identify the requirement items which are the most difficult to implement, thus facilitating decisions regarding allocating resources, assigning appropriate staff or diagnosing the need to train and qualify personnel, contributing to human resource planning. At the end of the study, the applicability of the proposed approach was evaluated in a case study, in which we observed that the company studied did not have sufficient conditions to implement the requirements of the standard on their own. Thus, it was proposed, through a multi-criteria method, selecting alternatives which included the hiring of consultants. This alternative was well accepted by the target company in the case study.

This thesis examines the impacts of inclement weather days on AP exam scores in public schools, specifically low socioeconomic districts, and the assessment of their current closure procedures. By investigating the potential disruption in scores by inclement weather days, I can create a new dataset in analyzing a field that has yet to be studied through this lens, in addition to advising future policy for district superintendents and state government officials. The areas studied include Massachusetts and Georgia, representing states that are properly prepared for inclement weather closures and are under-prepared for inclement weather, respectively. I use two research methods to fully understand the quantitative and qualitative effects of inclement weather closures. The first is a quantitative analysis of district-level data on inclement weather days and AP exam scores over the past five years. To accomplish this, I contacted public-school districts in the two states involved in the case study to get raw data on school closures and combine this with already available datasets on AP exam score performance. The second is a qualitative account of inclement weather days from teachers and superintendents from districts across both states to establish their opinions regarding school closures and investigate the decision-making process in canceling school. In this qualitative assessment, I observe the roles that socioeconomic status and public transportation, among other factors, play in cancelations. This thesis seeks to challenge the argument proposed by previous research that snow days have no effect on test performance. Previously, this was measured by looking at state-wide exams. By using AP exams as a performance measure instead, a more direct impact on exam scores is expected due to the immovable testing dates and content- specific nature of the exams. Policy recommendations are given to accommodate the negative relationship between closures and test scores, given socioeconomic status.