Preliminary Results on Ocean Surface Current around Taiwan Mapped by HF Radar

• Main Authors: Yu-LunHsueh, 薛宇倫
• Other Authors: Huang-Hui Huang
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/70579570321324582948

碩士 === 國立成功大學 === 水利及海洋工程學系碩博士班 === 101 === This study analyzes the data supplied by Coastal Ocean Dynamics Application Radar (CODAR) to investigate and characterize the marine-meteorology conditions around Taiwan. Comparing with the results of tidal harmonic analysis, the CODAR data are separated into horizontal and vertical components of velocity u and v. The velocities then decompose into ten components based on the approach of Empirical orthogonal function (EOF). Those components are used to reconstruct the flow fields. From the analysis, it is found that the first three components of u-velocity have over than 90 percent explanation amounts and v-velocity have about 75%. Both the residual distributions of different directors are shown as a normal one. Due to the different specification of CODAR system, the study distinguishes the case region into three parts: the north, the south and the west-east region. As results, that the north region is missing measurement in January, February, March, July and August. The direction is from northwest to southeast in April and November. In May, the flow field appears clockwise vortex but in June it is mess up. The ocean currents lead towards to the southwest Taiwan in September and December. The currents in October are away from east. The south case region is also missing measurement in winter and the currents flow from west to east generally. About the west-east region, the Kuroshio Current known as black tide represents the whole east part and in the west, there is the Penghu channel pushing water forward to the East China Sea. According the result of the single day, this study further selects the typhoon event to compare the flow field of each region with the real meteorological condition. It is found that the field leading direction is just the opposite way as mouth average during the Typhoon Saola in 2012.