碩士 / 國立臺灣海洋大學 / 環境生物與漁業科學學系 / 104 / The geographical position of Taiwan is located at the area easily influenced by the tropical cyclones in the Western Pacific. According to the statistics of the Central Weather Bureau, ten kinds of typhoon path were examined. It is important paths for the Northward moving typhoon (30%) to affect Taiwan excluding the tracks of the Westward moving typhoon (63%). This study was tried to select the Northward moving typhoons of the Fung Wong, Kong Rey, Ta Lim, and Rammasun to observe the upwelling phenomenon off northeastern Taiwan before and after the northward moving typhoons. The result as below:
1. The ekman pumping velocity varied between 2.11×10-6~2.11×10-5m/s as the northward moving typhoon passed the upwelling area off northeastern Taiwan.
The ekman pumping velocity was enhanced between 3.72~9.29×10-5m/s when the typhoon move near to the upwelling area. Ekman pumping velocity was decreased to 1.11~3.79×10 -5m/s when it move away after one week. For Fung Wong and Kong Rey typhoons, sea surface temperature was decreased between 0.53~2.02°C one week later. However, SST raised about 0.27~0.56°C after one week when typhoons of Ta Lim and Rammasun passed. These changes may be associated with the variation of wind field. In addition, variation for chl-a 0.044~0.086 mg/m3 and sea level high 7.65~17.74cm were also found in this study.
2. An upwelling index was defined as the difference of SST between the upwelling area and its adjacent area used in this study. The yearly and summer of upwelling index were significant fluctuated about 2.14~1.22°C and 0.26~1.15°C, respectively, which was possibly influenced by the phenomenon of ENSO. The slight increase of 0.075°C and 0.111°C per 10 year during the period of 1998 and 2015, suggested the velocity of upwelling was subsequently decreased by year.
| Identifer | oai:union.ndltd.org:TW/104NTOU5451036 |
| Date | January 2016 |
| Creators | Yao, Yi-Ting, 姚宜婷 |
| Contributors | Lee, Ming-An, Kuo, Yi-Chun, 李明安, 郭怡君 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 76 |
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