波浪和海流是海洋中兩項重要的物理要素，大部份的研究都分別探討之，然而，波浪和海流同時存在，其間也會產生交互作用相互影響，本研究目的即在於探討在海流出現時對波浪特性之影響。
研究分析主要透過方向波譜(Directional spectrum)進行，然而方向波譜分析方法有很多，本研究就四種常見的方向波譜分析方法進行比較，結果顯示貝斯推估法(BDM)對波浪方向特性整體的解析能力較佳。
本研究分析在高雄興達電廠棧橋海域7204筆陣列式波高儀觀測結果與同步之流速觀測資料。分析結果顯示：當波浪和海流反向(逆流)時，波浪能量產生堆疊，波高變大且與流速成正比，當流速增加0.3 m/s時，波浪能量增加2%；另外，在逆流條件下，逆向流強度提升會導致波浪主頻會從高頻往低頻移動，當流速超過0.6 m/s時，波浪主頻與無海流時主頻相比約會降低31%；至於波浪方向會受到海流的影響而有所偏移，當波浪與海流方向近乎垂直時，會出現最大的波向偏移，約為5.38° (波流向差45°時，波向偏移3.83°)，隨著海流速度的增加，此偏移量愈大。
本研究基於現場實測數據分析獲得上述結果，此結果與過去文獻的定性研究成果類似，但本研究提供了定量數值，對於掌握波流交互作用有了更多的認識。

Waves and ocean currents are two important physical elements in the ocean, waves and ocean currents coexist and interact with each other, thereby influencing another one. This study investigate the impact of the presence of ocean currents on wave characteristics.
This study primarily utilizes directional spectrum to examine the wave properties. There are various methods for analyzing directional spectra, we compare four common used methods derived by predecessors. The results show that the Bayesian Directional Method (BDM) exhibits better overall analytical abilities for wave direction characteristics.
The study analyzes data from 7204 wave height measurements obtained from an array-type wave gauge located in the vicinity of the Xingda Power Plant Stack Bridge in Kaohsiung. The analysis reveals that waves and ocean currents are in opposite directions (countercurrent), wave energy accumulates, resulting in increased wave height proportional to the flow velocity. A 0.3 m/s increase in flow velocity leads to a 2% increase in wave energy. Moreover, as the flow velocity increases, the waves tend to approach the point of breaking. Under countercurrent conditions, the dominant wave frequency shifts from high frequencies to low frequencies with increasing flow velocity. When the flow velocity exceeds 0.6 m/s, the dominant wave frequency decreases by approximately 31%. Wave direction is also affected by the ocean currents, causing a deviation. The maximum wave direction deviation occurs when the wave direction is nearly perpendicular to the current, at approximately 5.38°(with a 45°difference between wave and current directions, the wave direction deviation is 3.83°). This deviation increases with higher flow velocities.
The results are obtained based on the analysis in this study. They are consistent with qualitative findings from previous literature, but this study provides quantitative values, contributing a better understanding of wave-current interactions.

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