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181 leaves : ill. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Physics, 1971

Thesis (Ph.D.) -- University of Adelaide, Dept. of Physics, 1971.

Thesis (Ph. D.)--University of Adelaide, Dept. of Physics and Mathematical Physics, 1990. / Copies of author's previously published articles inserted. Includes bibliographical references (leaves 261-288).

Thesis (Ph. D.)--University of Adelaide, 1989. / Includes bibliographical references (leaves 117-130).

"Winds aloft are normally determined from the horizontal projection of an ascending balloon's path on a polar diagram. This method obtains a value for the average wind speed and direction for the layer through which the balloon has ascended during a two-minute interval by drawing a straight line between the horizontal projection of the balloon's position at the beginning and end of the two-minute interval. The horizontal projection of a balloon's actual path is a smooth curve and it is believed that a more accurate measurement of the average wind speed and direction for the layer will be obtained by determining the wind speed from the length of the curve for the two-minute interval and determining the direction from the tangent to the balloon's position along the curve at the intermediate time interval. The wind speed was computed by both methods for three months' data and the results compared with the purpose of determining a correction factor. The wind direction as determined by the method suggested was found not to vary appreciably from the direction determined by the conventional method. It was found that there is often a considerable difference in the wind speed as determined by the two methods especially at very low wind speeds, with the wind speed determined by the conventional method always being too small, but that it is impractical to apply a correction factor to reported winds when one considers the absolute value, rather than the percentual value, of the difference"--Abstract. / Typescript. / "August, 1956." / "Submitted to the Graduate Council of Florida State University in partial fulfillment of the requirements for the degree of Master of Science." / Includes bibliographical references (leaf 16).

Eight years (1980-87) of twice-daily high-resolution radiosonde data from a tropical mid-Pacific island station are analyzed to generate time series of the planetary boundary layer (PBL) top pressure, an ageostrophic parameter (related to the divergence), and a parameter of mean PBL specific humidity. Sample spectra of these time series are calculated along with a spectra for nighttime outgoing longwave radiation (OLR) data (centered at a gridpoint near the island station) and compared in order to investigate the relationship between the ageostrophy and dynamical phenomena of the tropical Pacific. Methods of boundary layer top diagnosis are compared. Data derived methods include temperature inversion detection, humidity jump detection, and wind shear detection. The model based diagnosis method uses a Richardson number scheme. Comparisons between data derived methods and model based methods show good agreement. Correlation coefficients for comparisons are all above 0.91. In each sample spectra, the dominant peak corresponds to the frequency of the annual cycle. With an estimated annual cycle removed from each of the time series the nighttime (12 GMT) sample spectra for PBL top pressure shows a peak at a frequency that corresponds to the 30-60 day Intraseasonal Oscillation (ISO). Removal of an estimated annual cycle was unsuccessful for the daytime (0 GMT) sample spectra for PBL top pressure, PBL mean specific humidity, and the ageostrophic parameter. Sample spectra of the ageostrophic parameter show peaks in the ISO frequency range for both 12 GMT and 0 GMT even before removal of the annual cycle was attempted. The ISO range peaks remained in the 12 GMT ageostrophic parameter spectrum when the annual cycle was successfully removed. The nighttime OLR spectrum is dominated by the annual cycle peak and its harmonics. The OLR spectrum also shows a significant peak in the ISO range of periods. Removal of an estimated annual cycle intensifies the peak in the ISO range. The ageostrophic parameter time series is compared to the results of an EOF analysis performed on the same 8 years of radiosonde humidity measurements. The first three EOF modes of specific humidity give sample spectra which are dominated by the annual cycle. With the annual cycle removed the sample spectra of the first and third EOF modes of specific humidity both show significant peaks in the ISO frequency range, while the second EOF mode sample spectrum is dominated by two peaks at frequencies corresponding to periods of approximately 4 and 5 months. The presence of common frequencies in the ISO range of the power spectra of the ageostrophic parameter (a measure of divergence), the nighttime OLR (a measure of deep convection), the nighttime planetary boundary layer top, and the first EOF mode of specific humidity, lends support to theories that relate the ISO to the interaction of dynamics and moist processes. / Graduation date: 1995

Copies of author's previously published articles inserted / Bibliography: leaves 261-288 / x, 288 leaves : ill. (some col.), maps ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Physics and Mathematical Physics, 1990

Bibliography : p. 333-342. / xiii, 342 p. : ill. (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Physics and Mathematical Physics, 1994?