Thesis (M.Sc. Physics)--University of Waikato, 2006. / Includes bibliographical references (p. 97-102)

It has been shown by Schlesinger and Mintz (1979) that the UCLA general circulation model (GCM) is able to simulate the observed negative correlation between the total amount of ozone in a vertical atmospheric column (the total ozone) and the eastward-propagating synoptic disturbances in the troposphere, with the total ozone maxima and minima located respectively at the troughs and ridges of the tropospheric waves. The goal of the present study was to understand how the GCM simulated this observed relationship. Our analysis shows that the transient-eddy total ozone disturbances were an omnipresent feature of the GCM January simulation in the northern hemisphere midlatitudes, just as they are in nature. It is also found that the transient-eddy total ozone disturbances in the northern hemisphere midlatitudes were closely related to the transient-eddy geopotential heights there throughout the entirety of the simulation. Furthermore, the correlations between these two quantities are negative up to the 72 mb level and attain their largest negative values at the 300 mb level. The analysis also shows that the transient-eddy disturbances in the stratosphere are out of phase with their counterparts in the troposphere, in accord with what would be expected from Dines compensation. In the GCM simulation there is a well-defined positive correlation between the total ozone and the ozone content in each of the model layers in the upper troposphere and lower and middle stratosphere. It is found that although layers 5-8 (19.3-150 mb) contain the largest percentage of the total ozone, it is predominantly layers 6-9 (37.3 -300 mb) that make the largest contribution to the temporal variations of total ozone. In accordance with the observations, a strong negative correlation is found between the simulated total ozone and the height of the simulated tropopause. However, changing the height of the tropopause cannot in itself change the total ozone, but rather only its partitioning between the stratosphere and the troposphere. Our analysis clearly shows that it is the ozone convergence and divergence in an atmospheric column, not the photochemical ozone production and destruction, which are responsible for the synoptic increases and decreases of total ozone. / Graduation date: 1988

Univ., Diss.--Bremen, 2005.

No abstract available. / Thesis (M.Sc.)-University of Natal, Durban, 1993.

The chemistry of stratospheric ozone is discussed and particular consideration is given to the role of chlorine compounds and to the impact of human activity on the ozone layer. An account is given of the methods used by other researchers to measure hydrogen chloride (HC1) in the stratosphere and their results are summarized. The pressure modulator radiometer (PMR) is an instrument which can be used to make remote measurements of atmospheric temperature and composition by sensing the radiation transmitted by or emitted from an atmospheric path containing gases with absorption bands in the infra-red. A balloon-borne PMR has been used to detect the absorption of solar radiation by the fundamental vibration-rotation band of HC1 at 3.5 micrometres. Using a limb scanning technique, the mixing ratio profile of HC1 has been measured over the height range, 16 to 39 km. It is shown that the amount of HC1 in an atmospheric path can be related to the PMR signals using a line-by-line method. The theory is developed in sufficiently general terms for it to be applicable to line-by-line calculations for many other gases with absorption bands in the infra-red. Consideration is given to the modelling of PMR measurements of transmission and emission both in the atmosphere and in the laboratory. The instrument used to measure HC1 is described in detail. The problems associated with the interpretation of the signals are discussed and an account of the instrument's laboratory testing is given. The reduction of the balloon flight data is described and the method used to retrieve the mixing ratio profile from the PMR signals is presented.

No description available.

Thesis (Ph. D.)--University of California, Los Angeles, 1992. / Vita. Includes bibliographical references (leaves 440-474).

Thesis (M.Sc.)--York University, 2005. Graduate Programme in Earth and Space Science. / Typescript. Includes bibliographical references (leaves 139-147). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://gateway.proquest.com/openurl?url%5Fver=Z39.88-2004&res%5Fdat=xri:pqdiss &rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:MR11793

Thesis (Ph. D.)--University of Iowa, 2007. / Supervisor: Gregory Carmichael. Includes bibliographical references (leaves 129-136).

This thesis aims to clarify the sources of, and mechanisms associated with, the generation of ozone maxima over the southern African region. Inasmuch as, tropospheric ozone concentration is a function of both chemistry and meteorology, this thesis concentrates on the role of atmospheric dynamics. Firstly, a statistical analysis of the relationship between total ozone and meteorological parameters revealed a generally weak negative relationship between total ozone and the height of the 500, 300 and 100 hPa geopotential surfaces. The relationship is best expressed by the passage of a mid-latitude cyclone while anticyclonic conditions exhibited a weak relationship. An examination of the spatial distribution of total ozone and potential vorticity (PV), during the passage of westerly troughs, prompted a more thorough investigation of the exchange of ozone between the stratosphere and troposphere. The relationship between tropospheric ozone, and low pressure and anticyclonic systems is investigated further using data obtained during the South African Fire-Atmospheric Research Initiative (SAFARI) conducted in 1992. Ozone concentrations, as expressed by ozonesonde data, reveal different characteristic profiles for the two scenarios. Explanations for the differences observed are sought in the observed circulation patterns during the experiment. Case studies at Okaukuejo (Namibia), Irene (South Africa) and Brazzaville (Congo), which were utilised as ground stations during SAFARI, are presented in an attempt to gain insight into the vertical distribution of ozone over the entire expanse of the study region. The role of convective systems in the generation of short-lived upper tropospheric ozone maxima at tropical latitudes is illustrated while the different vertical ozone signatures, expressed under cyclonic and anticyclonic systems as described earlier, are reconfirmed by the Okaukuejo and Irene data. An attempt is made to investigate dynamic links between the troposphere and stratosphere and the concomitant exchange of ozone during the passage of westerly trough systems. Particularly deep troughs or cut off low pressure systems are identified as important mechanisms in the generation of upper tropospheric ozone maxima. An examination of the vertical distribution of ozone at Irene during the passage of a COL, using data obtained from the SA'ARI 1994 experiment, suggests concurrence with Danielsen's (1968) model of tropopause folding. The intrusion of high PV and dry stratospheric air, coupled with downward flow near the tropopause, in the vicinity of the upper tropospheric disturbance, promotes the transport of ozone-rich air to tropospheric altitudes. The limited availability of data has severely hampered the understanding of tropospheric ozo~e in southern Africa in the past. This study demonstrates the value of daily vertical ozone data, even for very short periods. / Thesis (Ph.D.)-University of Natal, 1995.