Thesis (Ph. D.)--University of California, Davis, 2004. / Degree granted in Civil and Environmental Engineering. Includes bibliographical references. Also available online. (Restricted to UC campuses)

Ozone readings which exceeded the National Ambient Air Quality Standard of 120 ppbv were recorded in Miami, Florida during 1978 and 1980. Similar elevated concentrations of ozone extended across upper Florida and into the Southeastern portion of the United States. It is concluded that tropospheric transport of ozone into the Miami area occurs. This conclusion is supported by lead analyses of atmospheric samples taken in Miami and by isentropic trajectories. Six case studies are presented. In all cases transport of ozone into Florida appears to occur. In only four of the cases does this result in elevated ozone levels in Miami. In one case lower Florida was experiencing an oceanic influx of air and low ozone concentrations. In the other case Miami was experiencing a stagnation and high ozone concentrations apparently generated locally. The long range transport of ozone across the Southeastern United States appears to result from circulation within a weather pattern characterized by a stagnant high pressure system over the Southeastern United States.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Meteorology and Physical Oceanography, 1982. / Microfiche copy available in Archives and Science / Bibliography: leaves 40-41. / by Eduardo Pantig Olaguer. / M.S.

The accuracy of ozone measurements in the middle atmosphere is of great importance when determining its diurnal variation. A high time resolution of the measured data is desirable and depends on the sensitivity of the receiver used to detect the ozone. This thesis aims to improve the sensitivity of a groundbased 142 GHz microwave radiometer used for measuring atmospheric ozone data. This is done by replacing the previous receiver components with a series of new components and arranging them in different setups for comparison purposes. Mechanics and wiring were changed in order to install the setups along with changes in the optics. Each test setup could be implemented as a first step towards improving the sensitivity of the radiometer. The result show that the optics contribute with an unexpected addition of noise to the measurements and hence the overall performance and improvement of the radiometer could not be determined. Suggestions are made for further work which include improving the optics and performing cryo-measurements.

Tropospheric ozone columns (TCOs) derived from differences between the Dutch-Finnish Aura Ozone Monitoring Instrument (OMI) measurements of the total atmospheric ozone column and the Aura Microwave Limb Sounder (MLS) measurements of stratospheric ozone columns are discussed. Because the measurements by these two instruments are not spatially coincident, interpolation techniques, with emphasis on mapping the stratospheric columns in space and time using the relationships between lower stratospheric ozone and potential vorticity (PV) and geopotential heights (Z), are evaluated at mid-latitudes. It is shown that this PV mapping procedure produces somewhat better agreement in comparisons with ozonesonde measurements, particularly in winter, than does simple linear interpolation of the MLS stratospheric columns or the use of typical coincidence criteria at mid-latitudes. The OMI/MLS derived tropospheric columns are calculated to be 4 Dobson units (DU) smaller than the sonde measured columns at mid-latitudes. Standard deviations between the derived tropospheric columns and those measured by ozonesondes are 9 DU (30%) annually but they are just 6 DU (15%) in summer. Uncertainties in the interpolated MLS stratospheric columns are likely to be the primary cause of these standard deviations. An important advantage of the PV mapping approach is that it works well when MLS data are missing (e.g., when an orbit of measurements is missing). In the comparisons against ozonesonde measurements, it provides up to twice as many comparisons compared to the other techniques. The OMI/MLS derived tropospheric ozone columns have been compared with corresponding columns based on the Tropospheric Emission Spectrometer (TES) measurements, and Regional chEmical trAnsport Model (REAM) simulations. The variability of tropospheric ozone columns has been examined for spring and summer 2005 over North America and the surrounding oceans. Comparisons of monthly mean distributions show good agreements between OMI/MLS tropospheric ozone columns, REAM columns, and TES columns. Two six-day periods in March have been selected to study the periodic TCO enhancements in two regions, around the Baja peninsula (Mexico) and over the West Coast of California. Thirteen-day back trajectories and daily maps of carbon monoxide (CO) and ozone from GEOS-CHEM and OMI/MLS have been used to investigate the influence of cross-Pacific transport. It is concluded that in the first period of the case study, the high ozone concentrations in mid and lower troposphere over the West Coast of California have been under the influence of cross-Pacific transport. Meteorological fields indicate that the high ozone concentrations in the upper troposphere over the West Coast of California and the high TCOs over the Baja peninsula are associated with stratospheric intrusions through a deep Rossby wave breaking event. The correlations between REAM TCOs and surface ozone from Environmental Protection Agency ground network measurements indicate that the TCO enhancement over the West Coast is associated with an increase of surface ozone. The correlations of REAM TCOs with geopotential height, wind fields, and tropopause height during the case study period suggest that TCO enhancement is best characterized in springtime by decreases of geopotential height on the 500 mb surface.

Thesis (M. Sc)--York University, 2000. Graduate Programme in Physics and Astronomy. / Typescript. Includes bibliographical references (leaves 128-135). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://wwwlib.umi.com/cr/yorku/fullcit?pMQ59206.

Thesis (M.S.)--University of Tennessee, Knoxville, 2003. / Title from title page screen (viewed Sept. 17, 2003). Thesis advisor: Wayne T. Davis. Document formatted into pages (x, 102 p. : ill., maps, charts). Vita. Includes bibliographical references (p. 39-40).

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Planetary waves are known to play an important role in determining the annual variability in the severity of Antarctic ozone depletion. In this thesis, data obtained from the TOMS experiment on board the Nimbus-7 satellite are used to create global maps of total column ozone for each day from 1979 to 1992. Planetary wave morphology within these distributions is examined using spatial spectral analysis. The wave powers obtained are compared with a measure of the depth and area of the Antarctic ozone hole. A theoretical overview is given of middle atmosphere dynamics and how it influences the global distribution of ozone. Planetary waves play a predominant role in this dynamical distribution as they are responsible for the eddy transport of heat, momentum and long-lived tracers. A discussion of the equations of motion governing planetary wave propagation and their physical interpretation is given. The use of derived meteorological parameters, such as potential vorticity, in the study of planetary waves is developed. The theoretical tools, together with the equations of motion, are used to examine the excitation mechanisms for planetary waves. This theoretical analysis is also used to show that the strength of the westerly jet within the polar vortex determines which planetary wave modes can be expected in the geopotential height fields. In general only wavenumber 1 and 2 propagate during the Southern Hemisphere winter and the strength of these waves strongly modulates the severity of the Antarctic ozone depletion. Furthermore, the timing of the breakdown of the polar vortex is connected with the temporal variation of planetary wave power. A review of the current research in the field of planetary waves and the global distribution of ozone is given. To quantify planetary wave activity, spatial spectral analysis (Fourier Transforms) of midlatitude zonal profiles of total column ozone are used to calculate wave powers in the ozone distribution. Powers at wavenumber 1 to 6 are calculated for each day from 1979 to 1992 for both the Northern and Southern Hemispheres. The powers are seen to decrease with wavenumber throughout the year and the amplitude of wave modes 3 and higher is suppressed during the winter in accordance with the theoretical discussion. Southern Hemisphere wave powers are compared with a daily depleted mass of ozone over the Antarctic from 1979 to 1992. It is found that during years of high (low) planetary wave activity Antarctic ozone depletion is very weak (severe). Finally, the planetary wave morphology observed in the Southern Hemisphere total column ozone distribution is compared with geopotential height waves reported in the literature. Comparison of Northern Hemisphere wave powers and Arctic ozone depletion shows little or no correlation. To examine whether planetary waves may effect the interannual variability in Antarctic vortex temperatures, winter averaged 100 hPa upper air temperatures from SANAE (70°18' S, 2°21' W) are compared with derived planetary wave powers. It is found that during years of high (low) planetary wave activity the SANAE 100 hPa temperatures are above (below) the mean. Analysis of daily total column ozone and upper air temperatures at SANAE, during the winters of 1987 and 1988, shows that wave 1 forcing can significantly influence the day-to-day variation in these quantities. A statistical model of total ozone variation over the entire globe, from 1979 to 1992, has been developed. This model incorporates a long-term linear trend, an annual variation, a quasi-biennial oscillation, a solar cycle variation and a semiannual variation. Since monthly average total column ozone data are used in this model, short term planetary wave influences are masked, and the variations in global ozone are determined primarily by the 5 signals discussed above. However, analysis of the model coefficients indicates that planetary wave activity may significantly contribute to zonal asymmetry in global total ozone trends. Differences between model results and measured data are compared with planetary wave activity. The timing of the breakdown of the Antarctic circumpolar vortex causes large interannual differences in monthly average total column ozone for the months of October and November in the Southern Hemisphere. This analysis is made more specific for South Africa by examining the variation in monthly average total column ozone over the five South African cities of Pretoria, Bloemfontein, Durban, Port Elizabeth and Cape Town for the years 1979 to 1992. A model of surface erythemal irradiance as a function of total column ozone, time of the year and other meteorological parameters is developed. Total ozone data for the 5 cities, used within the context of the statistical model and the DV irradiance model, allows the prediction of future DV levels over South Africa to the year 2000. Planetary wave motion owes its existence to the conservation of potential vor-ticity. However, to make use of this conservation principle as a diagnostic for planetary wave propagation, it is necessary to know the conditions under which it is conserved. A formalism developed by Plumb and Ko (1992) has been used to suggest a technique whereby the 'lifetime' of potential vorticity may be determined. Use was made of data from the NCAR CCM2 model to test this hypothesis. The concentrations of long-lived tracers (CH4 and NzO) extracted from the CCM2 also show the effects of planetary wave breaking on the meridional distribution of these species. This study has important implications for airborne polar chemistry campaigns. / Thesis (Ph.D.)-University of Natal, 1994.