臺灣東部海域航運發達，船舶在此區域航行時受到海流影響，有可能導致船難事件的發生，本研究使用SCHISM三維水動力數值模式模擬這片海域的海流變化，同時也進行浮標實測資料的流速及流向分析，針對自然因素分析導致船難事件發生的原因。
和平港的浮標實測流向資料顯示，此區域的海流流向以東北流與西南流為主，在兩年中各占全年總資料數的超過20%，而對浮標實測流速資料的分析結果顯示，在水下7公尺處的全年平均流速最快，同時發現東北流與西南流的平均流速有明顯的季節性變化，東北流在夏季時最強；西南流則在秋冬時最強。統計水下7公尺這一深度中流速超過0.5 m/s的強烈東北流在各潮汐週期內的出現時機與漲退潮時的海流平均流速變化，推論船舶在高潮點時至高潮點後2小時內與低潮點後第1.5小時左右時進港是相對安全的時間。
本研究以和平港最近發生過的三起事故為例，藉由模式之模擬結果分析擱淺事件前後的海流變化，船舶在和平港主航道外需對抗強勁的大範圍東北流與南外防波堤處的繞射海流，因此保持船艏偏左的姿態航行，在船艏剛進入主航道時東北流消失，影響船艏的海流驟然減弱，與此同時船艉仍受到強勁東北流影響，可能造成整個船身往逆時針方向旋轉並在進入主航道時撞上位於西側的水下消波塊，且主航道內外的海流流速差異相當大，可能造成水手更難以掌握船舶動態，依據海流的模擬結果推論海流的變化為造成多起航線軌跡與碰撞處相似的和平港船舶擱淺事件的原因。

To find out why the shipwreck accidents happened, this study analyzes the in-suit data measured from the Hoping Harbor buoy. The ocean currents in this area predominantly flow northeast and southwest, it was also observed that there is a seasonal variation in the average speeds of the northeast and southwest currents. The annual average current speed is fastest at a depth of 7 meters. Statistics on the occurrence of strong northeast currents exceeding 0.5 m/s at a depth of 7 meters during tidal cycles, along with changes in average current speeds during high and low tides, suggest that the safest times for ships to enter the harbor are within 2 hours after high tide and around 1.5 hours after low tide. This study also uses SCHISM model to simulate three recent accidents at Hoping harbor, according to the simulation results, ships navigating outside the Hoping harbor must contend with a strong, wide-ranging northeast current and diffracted currents near the south outer breakwater. The simulation results show that the difference in current speeds between inside and outside the harbor can be up to tenfold. Therefore, maintaining a leftward heading is recommended. As the ship’s bow enters the harbor, the northeast current abruptly disappears, significantly reducing the influencing current on the bow. Meanwhile, the stern is still affected by the strong northeast current, potentially causing the ship to rotate counterclockwise and collide with the underwater wave-dissipating blocks on the west side of the main channel of Hoping harbor. The significant difference in current speeds inside and outside Hoping harbor can make it more challenging for sailors to control the ship’s dynamics. Based on the simulation results, it is inferred that variations in ocean currents are a contributing factor to multiple grounding incidents at Hoping harbor, characterized by similar navigational tracks and collision points.

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