Applying Discriminant Analysis Method to Investigate the Formation Factors of Concentric Eyewall Typhoons in the Western North Pacific
| Autor: | Li-Yuan Wang, 王立原 |
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| Rok vydání: | 2017 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 105 According to the previous researches, the northwest Pacific occurs the most concentric eyewall (CE) Typhoon. Using ECMWF Interrim reanalysis data and composite energy data derived from SSMI microwave satellite, and utilize discriminant analysis method, to analysis the CE typhoon cases and non-CE typhoon cases. At the last, get the class result and parameters contribution, then verify the cases during 2012-2015. The parameters used in this study are 850hPa relative vorticity, 850hPa relative humidity, 200hPa divergence, 850hPa-200hPa vertical wind shear, sea surface temperature, and composite energy. The hit rate during 2000-2011 is 80.6%, and the discriminant ability is over significant level. Besides, the bigger contribution are 850hPa-200hPa vertical wind shear, 850hPa relative vorticity, and composite energy. Then, set the threshold of discriminant score, and verify the cases that intensity are strong during 2012-2015. The hit rate is 82%, and we can know when will format CE structure before satellite observed by average 13.9 hrs in advanced. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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