Observations show the presence of localized regions in the atmosphere with diminished potential vorticity gradients, like in the tropical upper troposphere where outflow from deep convective regions plays an important role. The present work investigates the effect of forcing on the evolution of Rossby waves in a zero potential vorticity gradient environment. As a preliminary investigation, the barotropic case is studied, where the analogue of potential vorticity is absolute vorticity. / The analytic solution of the linearized problem shows that the streamfunction grows algebraically in time, and eventually develops a nonlinear critical layer. The numerical solution of the nonlinear problem within the critical layer shows that the nonlinearity and the forcing act together to halt the growth as coherent vortices are put in a nonlinear oscillatory regime. At long times, the critical layer solution settles to a quasi-steady state consisting of relatively large amplitude stationary vortices, with a set of small amplitude steadily-propagating vortices superimposed. These results are contrasted with the results of previous unforced problems.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.27509 |
| Date | January 1997 |
| Creators | Choboter, Paul F. |
| Contributors | Maslowe, Sherwin A. (advisor) |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Master of Science (Department of Mathematics and Statistics.) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 001617609, proquestno: MQ37107, Theses scanned by UMI/ProQuest. |
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