本文使用TOROS(Taiwan Ocean Radar Observing System)高頻雷達系統之遙測資料與POM(Princeton Ocean Model)數值模式模擬結果，分析三種不同颱風路徑的表面流場，探討颱風路徑和風場對流經臺灣東部海域黑潮的影響。

為掌握流場主要特性，本研究調整頻譜一階峰設定，有效框選颱風期間與表層海流有關的雷達回波訊號，並使用移動平均法調整受到電離層日夜變化干擾的TOROS資料，觀察颱風期間流場變化。並根據風場變化、Time-Stack流場圖、橫斷面平均流速與風速圖以及平面流場等方法，探討表層海流在颱風期間的變化。

本文分析結果整理如下：當颱風位於觀測區之東、東南與東北方，受颱風反氣旋形成向南之風場，造成向北的黑潮流速減弱；當颱風位於觀測區之西方，則形成向北風場，使流速增強；當颱風位於觀測區之南方，且颱風行進方向與黑潮同向，則形成向北風場，使流速增強，隨颱風接近流場增強又隨颱風遠離而流場減弱。
TOROS海流遙測資料受到雷達回波訊噪品質不穩定之影響，使得部分TOROS產出之表層海流流場不甚合理，造成颱風期間TOROS遙測資料與POM模式模擬兩者資料分析結果並非完全吻合，但整體而言趨勢上是一致且合理的。

TOROS (Taiwan Ocean Radar Observing System) High Frequency Radar (HRF) system data sets measured by the Taiwan Ocean Research Institute (TORI) and model simulations calculated by POM (Princeton Ocean Model) both are implemented to analyse Kuroshio current variation affected by different typhoon tracks. Three typhoon tracks, i.e. SOULIK, USAGI and KONG-RET, were investigated. Changed of current field during typhoon events were discussed.

To accurately capture key features of Kuroshio current, we first adjust the first- order setting for effectively grasp surface currents which are resolved from radar echo signals during typhoon events. The moving average method is also used to remove ionospheric disturbance of TOROS raw data and obtain reasonable results in terms of changes of flow field during typhoon attack to Taiwan Island.

The results of the analysis are summarized as follows. When typhoons come from southeast and northeast of the onset of study area (the margin of east continental self), which could cause southern wind field resulting in decrease of the Kuroshio current speed. On the contrary, when typhoons locate in the southeast and northeast of the study area, which could produce northern wind field leading to increase of the Kuroshio current speed. It is concluded that the Kuroshio current field depends on the typhoon wind field on the onset at the study area. It could enhance the Kuroshio current speed in the following direction, but reduce the speed in the opposite direction.

Numerical results obtained by POM show the same trend of changes for different typhoon tracks. The current of typhoons at different weaker depth was also studies. No significant change of Kuroshio current field at 100m water depth is found during SOULIK typhoon attack.

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