本研究使用二維外模式下的普林斯頓海洋模式(2-D external mode of the Princeton Ocean Model)模擬綠島尾流。藉由資料的輸入進行模式計算，探討計算範圍、地形水深、邊界水位、季節與風場等效應如何影響綠島尾流。輸入模式的資料包含了地形水深、邊界水位和風場。邊界水位是由HYbrid Coordinate Ocean Model (HYCOM)/ Navy Coupled Ocean Data Assimilation (NCODA)所提供，風場資料來源則為Physical Oceanography Distributed Active Archive Center (PO.DAAC)。
本研究以大計算範圍：台東開敞海域(Taitung Open Ocean, TOO)與小計算範圍：綠島海域(Green Island, GI)模擬黑潮流場及綠島尾流。模式結果顯示TOO能夠整體描述蘭嶼及綠島下游的渦街。然而與HYCOM/NCODA資料相比，GI可以更合理地描述綠島下游的渦街。不同的地形水深限制可以探討水深對綠島尾流的效應，由結果可知當水深限制在小於360公尺的情形下黑潮主軸與實際流場特性較為一致。這種水深限制的做法也呼應了黑潮影響區域不及深海的觀測結論，處於深海的水幾乎不會流動。在不同邊界水位輸入的模擬實驗中，發現當邊界水位造成的流速愈大則綠島後的渦街愈明顯。季節效應的模擬中顯現夏季流場較冬季大，並且夏季時綠島後產生的渦街也較冬季來得明顯。於風場效應的模擬結果可發現綠島尾流明顯受到風場影響。風場在夏季的例子中影響明顯，這種特性可能是由於西南季風所引起。

2-D external mode of the Princeton Ocean Model (POM) is applied to study Green Island wake induced by Kuroshio. Subjects such as effects of domain, bathymetry, water surface elevation, seasonal variation and wind field on Green Island wake are investigated. The input data include bathymetry, boundary surface elevations and wind fields. Boundary surface elevations are derived from HYbrid Coordinate Ocean Model (HYCOM)/ Navy Coupled Ocean Data Assimilation (NCODA) and wind fields are derived from Physical Oceanography Distributed Active Archive Center (PO.DAAC).
Numerical studies use Taitung Open Ocean (TOO) domain and Green Island (GI) domain for simulating Green Island wake. The results show that TOO is able to describe the whole vortex streets in the lee of Green Island and Orchid Island, while GI is only capable of describing vortex street behind Green Island with more reasonable flow field compared with HYCOM/NCODA results. Water depth limitation is varied to examine the depth effect on Green Island wake. It is found that the main stream of Kuroshio in the case of 360 m maximum depth limitation is more consistent with realistic flow characteristics. It is reasonable because the influence range of Kuroshio is on the top ocean layer. Model tests with different boundary surface elevation input conditions reveal that the higher the velocity is, the clearer the vortex street is. Seasonal effect in simulations show the velocity field is larger in summer than in winter. The vortex street in the lee of Green Island is stronger in summer but the weak vortex street occurs in winter. The wind effect on Green Island wake is significant. It is clear in the summer cases and it may be caused by the summer southwesterly monsoon.

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