本文應用台灣海洋研究中心所提供之高頻雷達系統(Coastal Ocean Dynamics Application Radar，CODAR)所量測到的台灣沿岸海域的海面流速，分別進行經驗正交函數法與調和分析做比較，再分別對整個台灣海域的表面海流流場做合成流速的討論，經由經驗正交函數(Empirical orthogonal function，EOF)所計算後會得到一個新的擬合流場，由十個成分所組成，u分量可以前三個主要成分解釋擬合後90%以上的流場，v分量的前三個成分疊加後的流場解釋量則是約75%。將殘差作百分比調查分布情況顯示最佳分布為Normal分布。CODAR測流系統因為規格不同，故將測區分為北區、南區以及東西區。結果顯示北區在一、二、三月以及七、八月沒有測得流場資料，在四月與十一月時的流向為西北往東南向，五月呈現順時針旋渦狀，六月則較為紊亂，九月與十二月海流往西南方向的陸地走，另外十月則向西流。南區流場在十、十一、十二月時沒有收錄資料，整體呈現由西向東流向太平洋的趨勢。東西區的部分，在東邊西太平洋以黑潮為主的流向由南向北流，在四、五月與九月時出現一大尺度順時針渦流，最大流速出現在靠近台灣東部沿岸；西邊流場以澎湖水道為主由南向北流往東海，在澎湖南方有一逆時針渦流，此逆時針渦流的南方又有一順時針渦流。在單日流場的部分，則以颱風事件做各區域流場與現實氣象情況做對比，其中以蘇拉颱風在2012年8月1日時在西區的流場走向改變為由北向南，與其月平均流向完全相反，最為特殊。

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.

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27. . 更多的高頻雷達相關資訊可參考台灣海洋科技研究中心官方網站：http://www.tori.org.tw/或CODAR公司官方網站：http://www.CodarOS.com 。