A large fraction of the Los Angeles ultrafine atmospheric aerosol UAA) consists of nanoparticle chain aggregates NCAs； Xiong and Friedlander, 2001). NCAs are often sized and collected using instruments that rely on inertial transport mechanisms. A new method of interpreting the aerodynamic diameter of NCAs was described. The method can be used to calculate aggregate …

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The focus of this dissertation is the study of stratified atmospheric flows in the presence of complex terrain. Two large-scale field study campaigns were carried out, each with a focus on a specific archetypal terrain. Each field study involved the utilization of remote and in-situ atmospheric monitoring devices to collect experimental data. The first of …

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Previous general aviation GA) accident studies showed that decision errors were more associated with fatal GA accidents than other kinds of human errors, and weather related accidents, especially continued visual flight rules VFR) flight into instrument meteorological conditions IMC), remained the major cause of fatal GA accidents. Thus, finding the underlying causes of GA pilots …

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Long baseline, carrier-phase differential GPS positioning in a coastal environment poses unique challenges. It is well known that differential GPS positioning results degrade as baseline length increases due to several sources of error, including the error introduced by differential troposphere. The effect of the troposphere on GPS has been extensively discussed by numerous researchers, either …

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Sea ice has proven to be a crucial element in the climate and overall heat budget of the globe. The behavior of sea ice is dependent on the presence of snow cover due to its impact on the thermal insulation and albedo of the system. An airborne FMCW radar was created to measure the depth …

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Disturbance in the ionosphere, such as Equatorial Plasma Bubbles (EPB), can cause scintillations in satellite communication and navigation signals. Far ultraviolet (FUV) radiation is used as a diagnostic to investigate the plasma distribution, and therefore investigate the evolution and development of EPBs. This FUV airglow is measured by a photometer within the plane of the …

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This thesis considers the effect of nitrogen oxides NO x) on organic peroxy radicals RO2) in atmospheric chemistry. Two broad areas are addressed. First, the theoretical model of the RO2 锛?NO reaction system is developed to understand the role of key intermediates ROONO) on RO2 锛?NO reaction products. Special emphasis is placed on understanding organic …

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Most pollution releases in urban areas occur at or near ground level and therefore well within the building canopy. In order to study the dispersion of these emissions, it is necessary to know the wind velocity profile inside the canopy of large groups of buildings or obstacles. An ultra-low-speed small wind tunnel was set up …

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In this thesis, the atmospheric mercury distributions in East Asia are studied using methods: model simulations with the backward trajectory analysis锛?4D-Var data assimilation approach using adjoint inverse model simulations. The main purposes of this study are to evaluate current estimate of mercury emissions, which inventory have huge uncertainties that lead to model predict which underestimate …

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Monitoring of precipitation using a high-frequency radar system such as X-band is becoming increasingly popular due to its lower cost compared to its counterpart at S-band. Networks of meteorological radar systems at higher frequencies are being pursued for targeted applications such as coverage over a city or a small basin. However, at higher frequencies, the …

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