Idealized three-dimensional numerical simulations of deep moist convection in the presence of a symmetric midlevel vortex are analyzed to understand the evolution of system-scale vertical vorticity during the very early stages of tropical cyclogenesis. A localized thermal perturbation initiates deep convection and the modified initial vortex is allowed to evolve over the 48-hour simulation period. During this time, surface momentum, heat, and moisture fluxes are excluded to eliminate any possible intensification by CISK or WISHE processes. A spatial filter is applied to the model output to separate system-scale and convective-scale features in an objective manner, whereby the filter scale is determined by a spectral analysis of the vertical vorticity field. It is found that the primary contribution to system-scale vorticity intensification comes from the convergence of convective-scale cyclonic vorticity, supplied by vortical hot towers (VHTs). Vorticity tilting is found to play an insignificant role in this development. The spatial filter approach offers an alternative viewpoint to the traditional symmetry/asymmetry method, and distinctively emphasizes the highly asymmetric evolution of the system-scale vortex. / A Thesis submitted to the Department of Meteorology in partial fulfillment of the requirements for the degree of Master of Science. / Fall Semester, 2009. / August 17, 2009. / Hot Tower, Vorticity, Vortex, Filter, Cyclogenesis, Tropical Cyclone, Deep Convection, Mesoscale / Includes bibliographical references. / Robert Hart, Professor Directing Thesis; Paul Reasor, Committee Member; Paul Ruscher, Committee Member.
| Identifer | oai:union.ndltd.org:fsu.edu/oai:fsu.digital.flvc.org:fsu_181236 |
| Contributors | Creighton, Glenn (authoraut), Hart, Robert (professor directing thesis), Reasor, Paul (committee member), Ruscher, Paul (committee member), Department of Earth, Ocean and Atmospheric Sciences (degree granting department), Florida State University (degree granting institution) |
| Publisher | Florida State University, Florida State University |
| Source Sets | Florida State University |
| Language | English, English |
| Detected Language | English |
| Type | Text, text |
| Format | 1 online resource, computer, application/pdf |
| Rights | 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. |
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