Some of the material in is restricted to members of the community. By logging in, you may be able to gain additional access to certain collections or items. If you have questions about access or logging in, please use the form on the Contact Page.
Here we present a new method of identifying wave activity in the tropical stratosphere. NCEP reanalysis II data from January 1, 1979, to December 31, 2010, was used to diagnose properties of vertically-propagating equatorial waves, including wave speed, wave length, wave tilting, and pressure torque. We band-pass ltered time series of these properties to isolate frequencies corresponding to that of the QBO, of which mean zonal wind anomaly is used as a proxy. Every property was found to display a strong quasi-biennial oscillation, indicating the activity of waves which translate these properties is linked to the QBO. The oscillation of properties which are dependent on wave type (Kelvin or Rossby-gravity wave), such as wave speed and wave length, are in phase with transitional periods from easterly mean zonal flow to westerly. Other properties which relate to the momentum carried by the waves prove to be in phase or of opposing phase as the QBO. This shows that the deposition of momentum by vertically-propagating waves peaks as the mean zonal flow peaks, providing evidence for the critical level absorption and regime descent theories of the QBO.
A Thesis submitted to the Department of Earth, Ocean, and Atmospheric Sciencein partial fulfillment of the requirements for the degree of Master of Science.
Includes bibliographical references.
Ming Cai, Professor Directing Thesis; Allan Clarke, Committee Member; Philip Sura, Committee Member.
Florida State University
Use and Reproduction
This Item is protected by copyright and/or related rights. You are free to use this Item in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s). The copyright in theses and dissertations completed at Florida State University is held by the students who author them.