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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Indoor/ambient residential air toxics results in rural western Montana

Underberg, Heidi Lee. January 2009 (has links)
Thesis (MS)--University of Montana, 2009. / Contents viewed on December 18, 2009. Title from author supplied metadata. Includes bibliographical references.
72

Ceilometer observations of Vancouver's urban boundary layer : validation and mixed-layer height estimation

Van der Kamp, Derek 11 1900 (has links)
A mini-lidar system, Vaisala's CL31 ceilometer, was installed within a suburban area of Vancouver, BC, for the purpose of making continuous observations of the boundary layer over a period of 11 months. Initial validation of the ceilometer for use in boundary layer observations was undertaken. This involved the comparison of ceilometer data with eight months of ground-level particulate matter measurements, as well as with 16 vertical profiles of particulate matter and meteorological data. Once a variety of persistent noise structures within the data were accounted for, it was found that the ceilometer data showed good agreement with the particulate matter data, suggesting its usefulness for assessing air-quality throughout the bottom 1km of the atmosphere. Additionally, two algorithms were developed in order to estimate the height of the convective boundary layer, or the mixed-layer height, from the ceilometer data. One involved the fitting of an ideal-profile to the measured data, while the other involved the location of a minimum-gradient in the backscatter profile. The performance of these two techniques were assessed and compared, and it was found that the ideal-profile method was the more robust of the two. Finally, mixed-layer heights were estimated for fair weather, convectively active days. In order to isolate such conditions, an automatic flagging algorithm was developed. However, additional manual assessment was needed to avoided unsuitable conditions. Mixed-layer heights were estimated for 19 days over an 11 month period. the estimates presented here were found to agree with previous observations. Daily maximum mixed-layer heights ranged from 650m in July to 350m in December, indicating that the height of the convective boundary layer within Vancouver is significantly suppressed due to the city's coastal location.
73

A model study of the influence of NMHC and NOx emissions on rural O₃ concentrations in Georgia

Zheng, Jiangfen 12 1900 (has links)
No description available.
74

A four-dimensional data assimilation method for air quality modeling

Mendoza Dominguez, Alberto 12 1900 (has links)
No description available.
75

Assessment of ambient concentrations of ionic species of PM₂₅ in Atlanta, Georgia

Andrew, Michael Shane 08 1900 (has links)
No description available.
76

Air Quality, Externalities, and Decentralized Environmental Regulation

Boskovic, Branko 02 August 2013 (has links)
This dissertation investigates the causes and effects of the decentralization of environmental regulation. In Chapter 1, I provide an historical overview of air pollution regulation in the U.S., which serves as the context for this dissertation. Chapter 2 develops a model of interjurisdictional environmental regulation where economic and pollution spillovers may arise. I show that these spillovers may cause local jurisdictions to seek decentralized regulatory control, which in turn generates inefficient outcomes. Chapter 3 investigates empirically whether the decentralization of air pollution regulation in the U.S. during 1971-1990 caused an increase in transboundary air pollution. I find that the transfer of regulatory authority from the federal government to an individual state generated a significant increase in air pollution observed at monitors in downwind states. These findings vary with distance to those states creating transboundary spillovers and across pollutants with different atmospheric lifetimes. This is consistent with the notion that local governments do not account for externalities that their policies generate. The final chapter estimates a model of interjurisdictional environmental regulation that allows for transboundary pollution and competition for firms. The interdependence in jurisdictions’ regulatory choices from the spillovers creates a challenging identification problem, which I address using exclusion restrictions derived from the atmospheric physics of pollution propagation. For total suspended particulates, transboundary pollution will typically occur only between contiguous neighbours in the direction of the wind. This implies that exogenous factors affecting pollution dispersion (such as wind velocity) in distant jurisdictions can serve as instruments for neighbours' endogenous policy choices: they do not affect a given jurisdiction's regulatory choice directly, but directly affect the choices of that jurisdiction's neighbours. I find that a shift from centralized to state regulatory control causes significant increases in the number of polluting firms that locate in that state and decreases elsewhere; the same shift increases ambient air pollution at home and in other states. I also find that state regulatory choices respond much more to changes in the number of firms than to pollution. Further, I show that the degree of decentralization and the observed pollution outcomes are far from the counterfactual efficient levels.
77

Air Quality, Externalities, and Decentralized Environmental Regulation

Boskovic, Branko 02 August 2013 (has links)
This dissertation investigates the causes and effects of the decentralization of environmental regulation. In Chapter 1, I provide an historical overview of air pollution regulation in the U.S., which serves as the context for this dissertation. Chapter 2 develops a model of interjurisdictional environmental regulation where economic and pollution spillovers may arise. I show that these spillovers may cause local jurisdictions to seek decentralized regulatory control, which in turn generates inefficient outcomes. Chapter 3 investigates empirically whether the decentralization of air pollution regulation in the U.S. during 1971-1990 caused an increase in transboundary air pollution. I find that the transfer of regulatory authority from the federal government to an individual state generated a significant increase in air pollution observed at monitors in downwind states. These findings vary with distance to those states creating transboundary spillovers and across pollutants with different atmospheric lifetimes. This is consistent with the notion that local governments do not account for externalities that their policies generate. The final chapter estimates a model of interjurisdictional environmental regulation that allows for transboundary pollution and competition for firms. The interdependence in jurisdictions’ regulatory choices from the spillovers creates a challenging identification problem, which I address using exclusion restrictions derived from the atmospheric physics of pollution propagation. For total suspended particulates, transboundary pollution will typically occur only between contiguous neighbours in the direction of the wind. This implies that exogenous factors affecting pollution dispersion (such as wind velocity) in distant jurisdictions can serve as instruments for neighbours' endogenous policy choices: they do not affect a given jurisdiction's regulatory choice directly, but directly affect the choices of that jurisdiction's neighbours. I find that a shift from centralized to state regulatory control causes significant increases in the number of polluting firms that locate in that state and decreases elsewhere; the same shift increases ambient air pollution at home and in other states. I also find that state regulatory choices respond much more to changes in the number of firms than to pollution. Further, I show that the degree of decentralization and the observed pollution outcomes are far from the counterfactual efficient levels.
78

Ceilometer observations of Vancouver's urban boundary layer : validation and mixed-layer height estimation

Van der Kamp, Derek 11 1900 (has links)
A mini-lidar system, Vaisala's CL31 ceilometer, was installed within a suburban area of Vancouver, BC, for the purpose of making continuous observations of the boundary layer over a period of 11 months. Initial validation of the ceilometer for use in boundary layer observations was undertaken. This involved the comparison of ceilometer data with eight months of ground-level particulate matter measurements, as well as with 16 vertical profiles of particulate matter and meteorological data. Once a variety of persistent noise structures within the data were accounted for, it was found that the ceilometer data showed good agreement with the particulate matter data, suggesting its usefulness for assessing air-quality throughout the bottom 1km of the atmosphere. Additionally, two algorithms were developed in order to estimate the height of the convective boundary layer, or the mixed-layer height, from the ceilometer data. One involved the fitting of an ideal-profile to the measured data, while the other involved the location of a minimum-gradient in the backscatter profile. The performance of these two techniques were assessed and compared, and it was found that the ideal-profile method was the more robust of the two. Finally, mixed-layer heights were estimated for fair weather, convectively active days. In order to isolate such conditions, an automatic flagging algorithm was developed. However, additional manual assessment was needed to avoided unsuitable conditions. Mixed-layer heights were estimated for 19 days over an 11 month period. the estimates presented here were found to agree with previous observations. Daily maximum mixed-layer heights ranged from 650m in July to 350m in December, indicating that the height of the convective boundary layer within Vancouver is significantly suppressed due to the city's coastal location.
79

Examination of the performance of AERMOD model under different world conditions /

Danish, Farzana. January 2006 (has links)
Thesis (M.S.C.E.)--University of Toledo, 2006. / Typescript. "Submitted as partial fulfillment of the requirements for Masters of Science degree in Civil Engineering." Bibliography: leaves 53-55.
80

The impacts of reactive terpene emissions from plants on air quality in Las Vegas, Nevada

Papiez, Maria R. January 2007 (has links)
Thesis (M.S.)--University of Nevada, Reno, 2007. / "May, 2007." Includes bibliographical references (leaves 109-116). Online version available on the World Wide Web.

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