Using the reflectivity and Doppler data of the Carvel radar, located near Edmonton, Alberta, for the summer of 2000 to 2004, we produced a mesocyclone climatology for a region within 120 km from the radar using the mesocyclone detection algorithm of the McGill Radar data Analysis, Processing and Interactive Display (RAPID) software system. The Upper level Vertically Integrated Liquid water content (UVIL) algorithm of the same software package has been used to detect strong convection. Two datasets were built. The first one consists of dates when mesocyclones occurred while the other includes dates characterized by strong convection but without mesocyclonic activity. A synoptic-scale analysis is conducted to identify the main differences between the atmospheric circulations of the two datasets. / The upper-tropospheric flow associated with the mesocyclonic events shows a highly amplified meridional circulation. A strong trough-ridge couplet is evident 48 hours prior to the event. This atmospheric feature is responsible for the development of a vorticity maximum that is advected into Alberta. Lee cyclogenesis in noticeable on the sea-level pressure field associated with mesocyclone activity along with a significant low-level warm temperature input in the region of study. The corresponding atmospheric patterns associated with non-mesocyclonic events do not present such large-scale precursors. The different atmospheric fields act to favour large-scale forcing for ascent when mesocyclones are going to occur.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.97931 |
| Date | January 2005 |
| Creators | Chouinard, Sébastien. |
| 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 Atmospheric and Oceanic Sciences.) |
| Rights | © Sébastien Chouinard, 2005 |
| Relation | alephsysno: 002339769, proquestno: AAIMR24643, Theses scanned by UMI/ProQuest. |
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